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commit bb1a71f upstream. My attempt at allowing MST to use the higher color depths has regressed some configurations. Apparently people have setups where all MST streams will fit into the DP link with 8bpc but won't fit with higher color depths. What we really should be doing is reducing the bpc for all the streams on the same link until they start to fit. But that requires a bit more work, so in the meantime let's revert back closer to the old behavior and limit MST to at most 8bpc. Cc: stable@vger.kernel.org Cc: Lyude Paul <lyude@redhat.com> Tested-by: Geoffrey Bennett <gmux22@gmail.com> Fixes: f147721 ("drm/i915: Remove the 8bpc shackles from DP MST") Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111505 Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190828102059.2512-1-ville.syrjala@linux.intel.com Reviewed-by: Lyude Paul <lyude@redhat.com> (cherry picked from commit 75427b2) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2eb0964 upstream. This bit was fliped on for "syncing dependencies between camera and graphics". BSpec has no recollection why, and it is causing unrecoverable GPU hangs with Vulkan compute workloads. From BSpec, setting bit5 to 0 enables relaxed padding requirements for buffers, 1D and 2D non-array, non-MSAA, non-mip-mapped linear surfaces; and *must* be set to 0h on skl+ to ensure "Out of Bounds" case is suppressed. Reported-by: Jason Ekstrand <jason@jlekstrand.net> Suggested-by: Jason Ekstrand <jason@jlekstrand.net> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110998 Fixes: 8424171 ("drm/i915/gen9: h/w w/a: syncing dependencies between camera and graphics") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Tested-by: denys.kostin@globallogic.com Cc: Jason Ekstrand <jason@jlekstrand.net> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: <stable@vger.kernel.org> # v4.1+ Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190904100707.7377-1-chris@chris-wilson.co.uk (cherry picked from commit 9d7b01e) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit fe163e5 ] syzbot reported: BUG: KMSAN: uninit-value in capi_write+0x791/0xa90 drivers/isdn/capi/capi.c:700 CPU: 0 PID: 10025 Comm: syz-executor379 Not tainted 4.20.0-rc7+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 capi_write+0x791/0xa90 drivers/isdn/capi/capi.c:700 do_loop_readv_writev fs/read_write.c:703 [inline] do_iter_write+0x83e/0xd80 fs/read_write.c:961 vfs_writev fs/read_write.c:1004 [inline] do_writev+0x397/0x840 fs/read_write.c:1039 __do_sys_writev fs/read_write.c:1112 [inline] __se_sys_writev+0x9b/0xb0 fs/read_write.c:1109 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1109 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 [...] The problem is that capi_write() is reading past the end of the message. Fix it by checking the message's length in the needed places. Reported-and-tested-by: syzbot+0849c524d9c634f5ae66@syzkaller.appspotmail.com Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit fe163e5 ] syzbot reported: BUG: KMSAN: uninit-value in capi_write+0x791/0xa90 drivers/isdn/capi/capi.c:700 CPU: 0 PID: 10025 Comm: syz-executor379 Not tainted 4.20.0-rc7+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 capi_write+0x791/0xa90 drivers/isdn/capi/capi.c:700 do_loop_readv_writev fs/read_write.c:703 [inline] do_iter_write+0x83e/0xd80 fs/read_write.c:961 vfs_writev fs/read_write.c:1004 [inline] do_writev+0x397/0x840 fs/read_write.c:1039 __do_sys_writev fs/read_write.c:1112 [inline] __se_sys_writev+0x9b/0xb0 fs/read_write.c:1109 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1109 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 [...] The problem is that capi_write() is reading past the end of the message. Fix it by checking the message's length in the needed places. Reported-and-tested-by: syzbot+0849c524d9c634f5ae66@syzkaller.appspotmail.com Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When the NBD_CFLAG_DESTROY_ON_DISCONNECT flag is set and at the same time when the socket is closed due to the server daemon is restarted, just before the last DISCONNET is totally done if we start a new connection by using the old nbd_index, there will be crashing randomly, like: <3>[ 110.151949] block nbd1: Receive control failed (result -32) <1>[ 110.152024] BUG: unable to handle page fault for address: 0000058000000840 <1>[ 110.152063] #PF: supervisor read access in kernel mode <1>[ 110.152083] #PF: error_code(0x0000) - not-present page <6>[ 110.152094] PGD 0 P4D 0 <4>[ 110.152106] Oops: 0000 [#1] SMP PTI <4>[ 110.152120] CPU: 0 PID: 6698 Comm: kworker/u5:1 Kdump: loaded Not tainted 5.3.0-rc4+ #2 <4>[ 110.152136] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 <4>[ 110.152166] Workqueue: knbd-recv recv_work [nbd] <4>[ 110.152187] RIP: 0010:__dev_printk+0xd/0x67 <4>[ 110.152206] Code: 10 e8 c5 fd ff ff 48 8b 4c 24 18 65 48 33 0c 25 28 00 [...] <4>[ 110.152244] RSP: 0018:ffffa41581f13d18 EFLAGS: 00010206 <4>[ 110.152256] RAX: ffffa41581f13d30 RBX: ffff96dd7374e900 RCX: 0000000000000000 <4>[ 110.152271] RDX: ffffa41581f13d20 RSI: 00000580000007f0 RDI: ffffffff970ec24f <4>[ 110.152285] RBP: ffffa41581f13d80 R08: ffff96dd7fc17908 R09: 0000000000002e56 <4>[ 110.152299] R10: ffffffff970ec24f R11: 0000000000000003 R12: ffff96dd7374e900 <4>[ 110.152313] R13: 0000000000000000 R14: ffff96dd7374e9d8 R15: ffff96dd6e3b02c8 <4>[ 110.152329] FS: 0000000000000000(0000) GS:ffff96dd7fc00000(0000) knlGS:0000000000000000 <4>[ 110.152362] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4>[ 110.152383] CR2: 0000058000000840 CR3: 0000000067cc6002 CR4: 00000000001606f0 <4>[ 110.152401] Call Trace: <4>[ 110.152422] _dev_err+0x6c/0x83 <4>[ 110.152435] nbd_read_stat.cold+0xda/0x578 [nbd] <4>[ 110.152448] ? __switch_to_asm+0x34/0x70 <4>[ 110.152468] ? __switch_to_asm+0x40/0x70 <4>[ 110.152478] ? __switch_to_asm+0x34/0x70 <4>[ 110.152491] ? __switch_to_asm+0x40/0x70 <4>[ 110.152501] ? __switch_to_asm+0x34/0x70 <4>[ 110.152511] ? __switch_to_asm+0x40/0x70 <4>[ 110.152522] ? __switch_to_asm+0x34/0x70 <4>[ 110.152533] recv_work+0x35/0x9e [nbd] <4>[ 110.152547] process_one_work+0x19d/0x340 <4>[ 110.152558] worker_thread+0x50/0x3b0 <4>[ 110.152568] kthread+0xfb/0x130 <4>[ 110.152577] ? process_one_work+0x340/0x340 <4>[ 110.152609] ? kthread_park+0x80/0x80 <4>[ 110.152637] ret_from_fork+0x35/0x40 This is very easy to reproduce by running the nbd-runner. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Xiubo Li <xiubli@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Observe a segmentation fault when 'perf stat' is asked to repeat forever
with the interval option.
Without fix:
# perf stat -r 0 -I 5000 -e cycles -a sleep 10
# time counts unit events
5.000211692 3,13,89,82,34,157 cycles
10.000380119 1,53,98,52,22,294 cycles
10.040467280 17,16,79,265 cycles
Segmentation fault
This problem was only observed when we use forever option aka -r 0 and
works with limited repeats. Calling print_counter with ts being set to
NULL, is not a correct option when interval is set. Hence avoid
print_counter(NULL,..) if interval is set.
With fix:
# perf stat -r 0 -I 5000 -e cycles -a sleep 10
# time counts unit events
5.019866622 3,15,14,43,08,697 cycles
10.039865756 3,15,16,31,95,261 cycles
10.059950628 1,26,05,47,158 cycles
5.009902655 3,14,52,62,33,932 cycles
10.019880228 3,14,52,22,89,154 cycles
10.030543876 66,90,18,333 cycles
5.009848281 3,14,51,98,25,437 cycles
10.029854402 3,15,14,93,04,918 cycles
5.009834177 3,14,51,95,92,316 cycles
Committer notes:
Did the 'git bisect' to find the cset introducing the problem to add the
Fixes tag below, and at that time the problem reproduced as:
(gdb) run stat -r0 -I500 sleep 1
<SNIP>
Program received signal SIGSEGV, Segmentation fault.
print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866
866 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, csv_sep);
(gdb) bt
#0 print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866
#1 0x000000000041860a in print_counters (ts=ts@entry=0x0, argc=argc@entry=2, argv=argv@entry=0x7fffffffd640) at builtin-stat.c:938
#2 0x0000000000419a7f in cmd_stat (argc=2, argv=0x7fffffffd640, prefix=<optimized out>) at builtin-stat.c:1411
#3 0x000000000045c65a in run_builtin (p=p@entry=0x6291b8 <commands+216>, argc=argc@entry=5, argv=argv@entry=0x7fffffffd640) at perf.c:370
#4 0x000000000045c893 in handle_internal_command (argc=5, argv=0x7fffffffd640) at perf.c:429
#5 0x000000000045c8f1 in run_argv (argcp=argcp@entry=0x7fffffffd4ac, argv=argv@entry=0x7fffffffd4a0) at perf.c:473
#6 0x000000000045cac9 in main (argc=<optimized out>, argv=<optimized out>) at perf.c:588
(gdb)
Mostly the same as just before this patch:
Program received signal SIGSEGV, Segmentation fault.
0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964
964 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, config->csv_sep);
(gdb) bt
#0 0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964
#1 0x0000000000588047 in perf_evlist__print_counters (evlist=0xbc9b90, config=0xa1f2a0 <stat_config>, _target=0xa1f0c0 <target>, ts=0x0, argc=2, argv=0x7fffffffd670)
at util/stat-display.c:1172
#2 0x000000000045390f in print_counters (ts=0x0, argc=2, argv=0x7fffffffd670) at builtin-stat.c:656
#3 0x0000000000456bb5 in cmd_stat (argc=2, argv=0x7fffffffd670) at builtin-stat.c:1960
#4 0x00000000004dd2e0 in run_builtin (p=0xa30e00 <commands+288>, argc=5, argv=0x7fffffffd670) at perf.c:310
#5 0x00000000004dd54d in handle_internal_command (argc=5, argv=0x7fffffffd670) at perf.c:362
#6 0x00000000004dd694 in run_argv (argcp=0x7fffffffd4cc, argv=0x7fffffffd4c0) at perf.c:406
#7 0x00000000004dda11 in main (argc=5, argv=0x7fffffffd670) at perf.c:531
(gdb)
Fixes: d4f63a4 ("perf stat: Introduce print_counters function")
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v4.2+
Link: http://lore.kernel.org/lkml/20190904094738.9558-3-srikar@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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We release wrong pointer on error path in cpu_cache_level__read function, leading to segfault: (gdb) r record ls Starting program: /root/perf/tools/perf/perf record ls ... [ perf record: Woken up 1 times to write data ] double free or corruption (out) Thread 1 "perf" received signal SIGABRT, Aborted. 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6 (gdb) bt #0 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6 #1 0x00007ffff7443bac in abort () from /lib64/power9/libc.so.6 #2 0x00007ffff74af8bc in __libc_message () from /lib64/power9/libc.so.6 #3 0x00007ffff74b92b8 in malloc_printerr () from /lib64/power9/libc.so.6 #4 0x00007ffff74bb874 in _int_free () from /lib64/power9/libc.so.6 #5 0x0000000010271260 in __zfree (ptr=0x7fffffffa0b0) at ../../lib/zalloc.. #6 0x0000000010139340 in cpu_cache_level__read (cache=0x7fffffffa090, cac.. #7 0x0000000010143c90 in build_caches (cntp=0x7fffffffa118, size=<optimiz.. ... Releasing the proper pointer. Fixes: 720e98b ("perf tools: Add perf data cache feature") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org: # v4.6+ Link: http://lore.kernel.org/lkml/20190912105235.10689-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Fix to skip making a same probe address on given line. Since a DWARF line info contains several entries for one line with different column, perf probe will make a different probe on same address if user specifies a probe point by "function:line" or "file:line". e.g. $ perf probe -D kernel_read:8 p:probe/kernel_read_L8 kernel_read+39 p:probe/kernel_read_L8_1 kernel_read+39 This skips such duplicated probe addresses. Committer testing: # uname -a Linux quaco 5.3.0+ #2 SMP Thu Sep 19 16:13:22 -03 2019 x86_64 x86_64 x86_64 GNU/Linux # Before: # perf probe -D kernel_read:8 p:probe/kernel_read _text+3115191 p:probe/kernel_read_1 _text+3115191 # After: # perf probe -D kernel_read:8 p:probe/kernel_read _text+3115191 # Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lore.kernel.org/lkml/156886447061.10772.4261569305869149178.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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ccw console is created early in start_kernel and used before css is initialized or ccw console subchannel is registered. Until then console subchannel does not have a parent. For that reason assume subchannels with no parent are not pseudo subchannels. This fixes the following kasan finding: BUG: KASAN: global-out-of-bounds in sch_is_pseudo_sch+0x8e/0x98 Read of size 8 at addr 00000000000005e8 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc8-07370-g6ac43dd12538 #2 Hardware name: IBM 2964 NC9 702 (z/VM 6.4.0) Call Trace: ([<000000000012cd76>] show_stack+0x14e/0x1e0) [<0000000001f7fb44>] dump_stack+0x1a4/0x1f8 [<00000000007d7afc>] print_address_description+0x64/0x3c8 [<00000000007d75f6>] __kasan_report+0x14e/0x180 [<00000000018a2986>] sch_is_pseudo_sch+0x8e/0x98 [<000000000189b950>] cio_enable_subchannel+0x1d0/0x510 [<00000000018cac7c>] ccw_device_recognition+0x12c/0x188 [<0000000002ceb1a8>] ccw_device_enable_console+0x138/0x340 [<0000000002cf1cbe>] con3215_init+0x25e/0x300 [<0000000002c8770a>] console_init+0x68a/0x9b8 [<0000000002c6a3d6>] start_kernel+0x4fe/0x728 [<0000000000100070>] startup_continue+0x70/0xd0 Cc: stable@vger.kernel.org Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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Patch series "Enable THP for text section of non-shmem files", v10;
This patchset follows up discussion at LSF/MM 2019. The motivation is to
put text section of an application in THP, and thus reduces iTLB miss rate
and improves performance. Both Facebook and Oracle showed strong
interests to this feature.
To make reviews easier, this set aims a mininal valid product. Current
version of the work does not have any changes to file system specific
code. This comes with some limitations (discussed later).
This set enables an application to "hugify" its text section by simply
running something like:
madvise(0x600000, 0x80000, MADV_HUGEPAGE);
Before this call, the /proc/<pid>/maps looks like:
00400000-074d0000 r-xp 00000000 00:27 2006927 app
After this call, part of the text section is split out and mapped to
THP:
00400000-00425000 r-xp 00000000 00:27 2006927 app
00600000-00e00000 r-xp 00200000 00:27 2006927 app <<< on THP
00e00000-074d0000 r-xp 00a00000 00:27 2006927 app
Limitations:
1. This only works for text section (vma with VM_DENYWRITE).
2. Original limitation #2 is removed in v3.
We gated this feature with an experimental config, READ_ONLY_THP_FOR_FS.
Once we get better support on the write path, we can remove the config and
enable it by default.
Tested cases:
1. Tested with btrfs and ext4.
2. Tested with real work application (memcache like caching service).
3. Tested with "THP aware uprobe":
https://patchwork.kernel.org/project/linux-mm/list/?series=131339
This patch (of 7):
Currently, filemap_fault() avoids race condition with truncate by checking
page->mapping == mapping. This does not work for compound pages. This
patch let it check compound_head(page)->mapping instead.
Link: http://lkml.kernel.org/r/20190801184244.3169074-2-songliubraving@fb.com
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Rik van Riel <riel@surriel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Update MAINTAINERS record to reflect that trusted.h was moved to a different directory in commit 2244798 ("KEYS: Move trusted.h to include/keys [ver #2]"). Cc: Denis Kenzior <denkenz@gmail.com> Cc: James Bottomley <jejb@linux.ibm.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: linux-integrity@vger.kernel.org Signed-off-by: Denis Efremov <efremov@linux.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
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I'm seeing a bunch of debug prints from a user of print_hex_dump_bytes() in my kernel logs, but I don't have CONFIG_DYNAMIC_DEBUG enabled nor do I have DEBUG defined in my build. The problem is that print_hex_dump_bytes() calls a wrapper function in lib/hexdump.c that calls print_hex_dump() with KERN_DEBUG level. There are three cases to consider here 1. CONFIG_DYNAMIC_DEBUG=y --> call dynamic_hex_dum() 2. CONFIG_DYNAMIC_DEBUG=n && DEBUG --> call print_hex_dump() 3. CONFIG_DYNAMIC_DEBUG=n && !DEBUG --> stub it out Right now, that last case isn't detected and we still call print_hex_dump() from the stub wrapper. Let's make print_hex_dump_bytes() only call print_hex_dump_debug() so that it works properly in all cases. Case #1, print_hex_dump_debug() calls dynamic_hex_dump() and we get same behavior. Case #2, print_hex_dump_debug() calls print_hex_dump() with KERN_DEBUG and we get the same behavior. Case #3, print_hex_dump_debug() is a nop, changing behavior to what we want, i.e. print nothing. Link: http://lkml.kernel.org/r/20190816235624.115280-1-swboyd@chromium.org Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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After commit a2c11b0 ("kcm: use BPF_PROG_RUN") syzbot easily triggers the warning in cant_sleep(). As explained in commit 6cab5e9 ("bpf: run bpf programs with preemption disabled") we need to disable preemption before running bpf programs. BUG: assuming atomic context at net/kcm/kcmsock.c:382 in_atomic(): 0, irqs_disabled(): 0, pid: 7, name: kworker/u4:0 3 locks held by kworker/u4:0/7: #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: ffff8880a989fdc0 ((work_completion)(&strp->work)){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: ffff888098998d10 (sk_lock-AF_INET){+.+.}, at: lock_sock include/net/sock.h:1522 [inline] #2: ffff888098998d10 (sk_lock-AF_INET){+.+.}, at: strp_sock_lock+0x2e/0x40 net/strparser/strparser.c:440 CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: kstrp strp_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 __cant_sleep kernel/sched/core.c:6826 [inline] __cant_sleep.cold+0xa4/0xbc kernel/sched/core.c:6803 kcm_parse_func_strparser+0x54/0x200 net/kcm/kcmsock.c:382 __strp_recv+0x5dc/0x1b20 net/strparser/strparser.c:221 strp_recv+0xcf/0x10b net/strparser/strparser.c:343 tcp_read_sock+0x285/0xa00 net/ipv4/tcp.c:1639 strp_read_sock+0x14d/0x200 net/strparser/strparser.c:366 do_strp_work net/strparser/strparser.c:414 [inline] strp_work+0xe3/0x130 net/strparser/strparser.c:423 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 Fixes: a2c11b0 ("kcm: use BPF_PROG_RUN") Fixes: 6cab5e9 ("bpf: run bpf programs with preemption disabled") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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qdisc_root() use from netem_enqueue() triggers a lockdep warning.
__dev_queue_xmit() uses rcu_read_lock_bh() which is
not equivalent to rcu_read_lock() + local_bh_disable_bh as far
as lockdep is concerned.
WARNING: suspicious RCU usage
5.3.0-rc7+ #0 Not tainted
-----------------------------
include/net/sch_generic.h:492 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz-executor427/8855:
#0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline]
#0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x2dc/0x2570 net/ipv4/ip_output.c:214
#1: 00000000b5525c01 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x20a/0x3650 net/core/dev.c:3804
#2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: spin_lock include/linux/spinlock.h:338 [inline]
#2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_xmit_skb net/core/dev.c:3502 [inline]
#2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_queue_xmit+0x14b8/0x3650 net/core/dev.c:3838
stack backtrace:
CPU: 0 PID: 8855 Comm: syz-executor427 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5357
qdisc_root include/net/sch_generic.h:492 [inline]
netem_enqueue+0x1cfb/0x2d80 net/sched/sch_netem.c:479
__dev_xmit_skb net/core/dev.c:3527 [inline]
__dev_queue_xmit+0x15d2/0x3650 net/core/dev.c:3838
dev_queue_xmit+0x18/0x20 net/core/dev.c:3902
neigh_hh_output include/net/neighbour.h:500 [inline]
neigh_output include/net/neighbour.h:509 [inline]
ip_finish_output2+0x1726/0x2570 net/ipv4/ip_output.c:228
__ip_finish_output net/ipv4/ip_output.c:308 [inline]
__ip_finish_output+0x5fc/0xb90 net/ipv4/ip_output.c:290
ip_finish_output+0x38/0x1f0 net/ipv4/ip_output.c:318
NF_HOOK_COND include/linux/netfilter.h:294 [inline]
ip_mc_output+0x292/0xf40 net/ipv4/ip_output.c:417
dst_output include/net/dst.h:436 [inline]
ip_local_out+0xbb/0x190 net/ipv4/ip_output.c:125
ip_send_skb+0x42/0xf0 net/ipv4/ip_output.c:1555
udp_send_skb.isra.0+0x6b2/0x1160 net/ipv4/udp.c:887
udp_sendmsg+0x1e96/0x2820 net/ipv4/udp.c:1174
inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807
sock_sendmsg_nosec net/socket.c:637 [inline]
sock_sendmsg+0xd7/0x130 net/socket.c:657
___sys_sendmsg+0x3e2/0x920 net/socket.c:2311
__sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413
__do_sys_sendmmsg net/socket.c:2442 [inline]
__se_sys_sendmmsg net/socket.c:2439 [inline]
__x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2439
do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Ido Schimmel says: ==================== mlxsw: Various fixes This patchset includes two small fixes for the mlxsw driver and one patch which clarifies recently introduced devlink-trap documentation. Patch #1 clears the port's VLAN filters during port initialization. This ensures that the drop reason reported to the user is consistent. The problem is explained in detail in the commit message. Patch #2 clarifies the description of one of the traps exposed via devlink-trap. Patch #3 from Danielle forbids the installation of a tc filter with multiple mirror actions since this is not supported by the device. The failure is communicated to the user via extack. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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commit bd200d1 upstream. [Why] DRM private objects have no hw_done/flip_done fencing mechanism on their own and cannot be used to sequence commits accordingly. When issuing commits that don't touch the same set of hardware resources like page-flips on different CRTCs we can run into the issue below because of this: 1. Client requests non-blocking Commit #1, has a new dc_state #1, state is swapped, commit tail is deferred to work queue 2. Client requests non-blocking Commit #2, has a new dc_state #2, state is swapped, commit tail is deferred to work queue 3. Commit #2 work starts, commit tail finishes, atomic state is cleared, dc_state #1 is freed 4. Commit #1 work starts, commit tail encounters null pointer deref on dc_state #1 In order to change the DC state as in the private object we need to ensure that we wait for all outstanding commits to finish and that any other pending commits must wait for the current one to finish as well. We do this for MEDIUM and FULL updates. But not for FAST updates, nor would we want to since it would cause stuttering from the delays. FAST updates that go through dm_determine_update_type_for_commit always create a new dc_state and lock the DRM private object if there are any changed planes. We need the old state to validate, but we don't actually need the new state here. [How] If the commit isn't a full update then the use after free can be resolved by simply discarding the new state entirely and retaining the existing one instead. With this change the sequence above can be reexamined. Commit #2 will still free Commit #1's reference, but before this happens we actually added an additional reference as part of Commit #2. If an update comes in during this that needs to change the dc_state it will need to wait on Commit #1 and Commit #2 to finish. Then it'll swap the state, finish the work in commit tail and drop the last reference on Commit #2's dc_state. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204181 Fixes: 004b393 ("drm/amd/display: Check scaling info when determing update type") Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: David Francis <david.francis@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit bd200d1 upstream. [Why] DRM private objects have no hw_done/flip_done fencing mechanism on their own and cannot be used to sequence commits accordingly. When issuing commits that don't touch the same set of hardware resources like page-flips on different CRTCs we can run into the issue below because of this: 1. Client requests non-blocking Commit #1, has a new dc_state #1, state is swapped, commit tail is deferred to work queue 2. Client requests non-blocking Commit #2, has a new dc_state #2, state is swapped, commit tail is deferred to work queue 3. Commit #2 work starts, commit tail finishes, atomic state is cleared, dc_state #1 is freed 4. Commit #1 work starts, commit tail encounters null pointer deref on dc_state #1 In order to change the DC state as in the private object we need to ensure that we wait for all outstanding commits to finish and that any other pending commits must wait for the current one to finish as well. We do this for MEDIUM and FULL updates. But not for FAST updates, nor would we want to since it would cause stuttering from the delays. FAST updates that go through dm_determine_update_type_for_commit always create a new dc_state and lock the DRM private object if there are any changed planes. We need the old state to validate, but we don't actually need the new state here. [How] If the commit isn't a full update then the use after free can be resolved by simply discarding the new state entirely and retaining the existing one instead. With this change the sequence above can be reexamined. Commit #2 will still free Commit #1's reference, but before this happens we actually added an additional reference as part of Commit #2. If an update comes in during this that needs to change the dc_state it will need to wait on Commit #1 and Commit #2 to finish. Then it'll swap the state, finish the work in commit tail and drop the last reference on Commit #2's dc_state. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204181 Fixes: 004b393 ("drm/amd/display: Check scaling info when determing update type") Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: David Francis <david.francis@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When a cpu requests broadcasting, before starting the tick broadcast hrtimer, bc_set_next() checks if the timer callback (bc_handler) is active using hrtimer_try_to_cancel(). But hrtimer_try_to_cancel() does not provide the required synchronization when the callback is active on other core. The callback could have already executed tick_handle_oneshot_broadcast() and could have also returned. But still there is a small time window where the hrtimer_try_to_cancel() returns -1. In that case bc_set_next() returns without doing anything, but the next_event of the tick broadcast clock device is already set to a timeout value. In the race condition diagram below, CPU #1 is running the timer callback and CPU #2 is entering idle state and so calls bc_set_next(). In the worst case, the next_event will contain an expiry time, but the hrtimer will not be started which happens when the racing callback returns HRTIMER_NORESTART. The hrtimer might never recover if all further requests from the CPUs to subscribe to tick broadcast have timeout greater than the next_event of tick broadcast clock device. This leads to cascading of failures and finally noticed as rcu stall warnings Here is a depiction of the race condition CPU #1 (Running timer callback) CPU #2 (Enter idle and subscribe to tick broadcast) --------------------- --------------------- __run_hrtimer() tick_broadcast_enter() bc_handler() __tick_broadcast_oneshot_control() tick_handle_oneshot_broadcast() raw_spin_lock(&tick_broadcast_lock); dev->next_event = KTIME_MAX; //wait for tick_broadcast_lock //next_event for tick broadcast clock set to KTIME_MAX since no other cores subscribed to tick broadcasting raw_spin_unlock(&tick_broadcast_lock); if (dev->next_event == KTIME_MAX) return HRTIMER_NORESTART // callback function exits without restarting the hrtimer //tick_broadcast_lock acquired raw_spin_lock(&tick_broadcast_lock); tick_broadcast_set_event() clockevents_program_event() dev->next_event = expires; bc_set_next() hrtimer_try_to_cancel() //returns -1 since the timer callback is active. Exits without restarting the timer cpu_base->running = NULL; The comment that hrtimer cannot be armed from within the callback is wrong. It is fine to start the hrtimer from within the callback. Also it is safe to start the hrtimer from the enter/exit idle code while the broadcast handler is active. The enter/exit idle code and the broadcast handler are synchronized using tick_broadcast_lock. So there is no need for the existing try to cancel logic. All this can be removed which will eliminate the race condition as well. Fixes: 5d1638a ("tick: Introduce hrtimer based broadcast") Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190926135101.12102-2-balasubramani_vivekanandan@mentor.com
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This patch fixes the lock inversion complaint: ============================================ WARNING: possible recursive locking detected 5.3.0-rc7-dbg+ #1 Not tainted -------------------------------------------- kworker/u16:6/171 is trying to acquire lock: 00000000035c6e6c (&id_priv->handler_mutex){+.+.}, at: rdma_destroy_id+0x78/0x4a0 [rdma_cm] but task is already holding lock: 00000000bc7c307d (&id_priv->handler_mutex){+.+.}, at: iw_conn_req_handler+0x151/0x680 [rdma_cm] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&id_priv->handler_mutex); lock(&id_priv->handler_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kworker/u16:6/171: #0: 00000000e2eaa773 ((wq_completion)iw_cm_wq){+.+.}, at: process_one_work+0x472/0xac0 #1: 000000001efd357b ((work_completion)(&work->work)#3){+.+.}, at: process_one_work+0x476/0xac0 #2: 00000000bc7c307d (&id_priv->handler_mutex){+.+.}, at: iw_conn_req_handler+0x151/0x680 [rdma_cm] stack backtrace: CPU: 3 PID: 171 Comm: kworker/u16:6 Not tainted 5.3.0-rc7-dbg+ #1 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: iw_cm_wq cm_work_handler [iw_cm] Call Trace: dump_stack+0x8a/0xd6 __lock_acquire.cold+0xe1/0x24d lock_acquire+0x106/0x240 __mutex_lock+0x12e/0xcb0 mutex_lock_nested+0x1f/0x30 rdma_destroy_id+0x78/0x4a0 [rdma_cm] iw_conn_req_handler+0x5c9/0x680 [rdma_cm] cm_work_handler+0xe62/0x1100 [iw_cm] process_one_work+0x56d/0xac0 worker_thread+0x7a/0x5d0 kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 This is not a bug as there are actually two lock classes here. Link: https://lore.kernel.org/r/20190930231707.48259-3-bvanassche@acm.org Fixes: de910bd ("RDMA/cma: Simplify locking needed for serialization of callbacks") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
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A user reported a lockdep splat ====================================================== WARNING: possible circular locking dependency detected 5.2.11-gentoo #2 Not tainted ------------------------------------------------------ kswapd0/711 is trying to acquire lock: 000000007777a663 (sb_internal){.+.+}, at: start_transaction+0x3a8/0x500 but task is already holding lock: 000000000ba86300 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}: kmem_cache_alloc+0x1f/0x1c0 btrfs_alloc_inode+0x1f/0x260 alloc_inode+0x16/0xa0 new_inode+0xe/0xb0 btrfs_new_inode+0x70/0x610 btrfs_symlink+0xd0/0x420 vfs_symlink+0x9c/0x100 do_symlinkat+0x66/0xe0 do_syscall_64+0x55/0x1c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (sb_internal){.+.+}: __sb_start_write+0xf6/0x150 start_transaction+0x3a8/0x500 btrfs_commit_inode_delayed_inode+0x59/0x110 btrfs_evict_inode+0x19e/0x4c0 evict+0xbc/0x1f0 inode_lru_isolate+0x113/0x190 __list_lru_walk_one.isra.4+0x5c/0x100 list_lru_walk_one+0x32/0x50 prune_icache_sb+0x36/0x80 super_cache_scan+0x14a/0x1d0 do_shrink_slab+0x131/0x320 shrink_node+0xf7/0x380 balance_pgdat+0x2d5/0x640 kswapd+0x2ba/0x5e0 kthread+0x147/0x160 ret_from_fork+0x24/0x30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(sb_internal); lock(fs_reclaim); lock(sb_internal); *** DEADLOCK *** 3 locks held by kswapd0/711: #0: 000000000ba86300 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x30 #1: 000000004a5100f8 (shrinker_rwsem){++++}, at: shrink_node+0x9a/0x380 #2: 00000000f956fa46 (&type->s_umount_key#30){++++}, at: super_cache_scan+0x35/0x1d0 stack backtrace: CPU: 7 PID: 711 Comm: kswapd0 Not tainted 5.2.11-gentoo #2 Hardware name: Dell Inc. Precision Tower 3620/0MWYPT, BIOS 2.4.2 09/29/2017 Call Trace: dump_stack+0x85/0xc7 print_circular_bug.cold.40+0x1d9/0x235 __lock_acquire+0x18b1/0x1f00 lock_acquire+0xa6/0x170 ? start_transaction+0x3a8/0x500 __sb_start_write+0xf6/0x150 ? start_transaction+0x3a8/0x500 start_transaction+0x3a8/0x500 btrfs_commit_inode_delayed_inode+0x59/0x110 btrfs_evict_inode+0x19e/0x4c0 ? var_wake_function+0x20/0x20 evict+0xbc/0x1f0 inode_lru_isolate+0x113/0x190 ? discard_new_inode+0xc0/0xc0 __list_lru_walk_one.isra.4+0x5c/0x100 ? discard_new_inode+0xc0/0xc0 list_lru_walk_one+0x32/0x50 prune_icache_sb+0x36/0x80 super_cache_scan+0x14a/0x1d0 do_shrink_slab+0x131/0x320 shrink_node+0xf7/0x380 balance_pgdat+0x2d5/0x640 kswapd+0x2ba/0x5e0 ? __wake_up_common_lock+0x90/0x90 kthread+0x147/0x160 ? balance_pgdat+0x640/0x640 ? __kthread_create_on_node+0x160/0x160 ret_from_fork+0x24/0x30 This is because btrfs_new_inode() calls new_inode() under the transaction. We could probably move the new_inode() outside of this but for now just wrap it in memalloc_nofs_save(). Reported-by: Zdenek Sojka <zsojka@seznam.cz> Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode") CC: stable@vger.kernel.org # 4.16+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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commit f8659d6 upstream. Define the working variables to be unsigned long to be compatible with for_each_set_bit and change types as needed. While we are at it remove unused variables from a couple of functions. This was found because of the following KASAN warning: ================================================================== BUG: KASAN: stack-out-of-bounds in find_first_bit+0x19/0x70 Read of size 8 at addr ffff888362d778d0 by task kworker/u308:2/1889 CPU: 21 PID: 1889 Comm: kworker/u308:2 Tainted: G W 5.3.0-rc2-mm1+ #2 Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.02.04.0003.102320141138 10/23/2014 Workqueue: ib-comp-unb-wq ib_cq_poll_work [ib_core] Call Trace: dump_stack+0x9a/0xf0 ? find_first_bit+0x19/0x70 print_address_description+0x6c/0x332 ? find_first_bit+0x19/0x70 ? find_first_bit+0x19/0x70 __kasan_report.cold.6+0x1a/0x3b ? find_first_bit+0x19/0x70 kasan_report+0xe/0x12 find_first_bit+0x19/0x70 pma_get_opa_portstatus+0x5cc/0xa80 [hfi1] ? ret_from_fork+0x3a/0x50 ? pma_get_opa_port_ectrs+0x200/0x200 [hfi1] ? stack_trace_consume_entry+0x80/0x80 hfi1_process_mad+0x39b/0x26c0 [hfi1] ? __lock_acquire+0x65e/0x21b0 ? clear_linkup_counters+0xb0/0xb0 [hfi1] ? check_chain_key+0x1d7/0x2e0 ? lock_downgrade+0x3a0/0x3a0 ? match_held_lock+0x2e/0x250 ib_mad_recv_done+0x698/0x15e0 [ib_core] ? clear_linkup_counters+0xb0/0xb0 [hfi1] ? ib_mad_send_done+0xc80/0xc80 [ib_core] ? mark_held_locks+0x79/0xa0 ? _raw_spin_unlock_irqrestore+0x44/0x60 ? rvt_poll_cq+0x1e1/0x340 [rdmavt] __ib_process_cq+0x97/0x100 [ib_core] ib_cq_poll_work+0x31/0xb0 [ib_core] process_one_work+0x4ee/0xa00 ? pwq_dec_nr_in_flight+0x110/0x110 ? do_raw_spin_lock+0x113/0x1d0 worker_thread+0x57/0x5a0 ? process_one_work+0xa00/0xa00 kthread+0x1bb/0x1e0 ? kthread_create_on_node+0xc0/0xc0 ret_from_fork+0x3a/0x50 The buggy address belongs to the page: page:ffffea000d8b5dc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x17ffffc0000000() raw: 0017ffffc0000000 0000000000000000 ffffea000d8b5dc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected addr ffff888362d778d0 is located in stack of task kworker/u308:2/1889 at offset 32 in frame: pma_get_opa_portstatus+0x0/0xa80 [hfi1] this frame has 1 object: [32, 36) 'vl_select_mask' Memory state around the buggy address: ffff888362d77780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888362d77800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888362d77880: 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 00 00 ^ ffff888362d77900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888362d77980: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 ================================================================== Cc: <stable@vger.kernel.org> Fixes: 7724105 ("IB/hfi1: add driver files") Link: https://lore.kernel.org/r/20190911113053.126040.47327.stgit@awfm-01.aw.intel.com Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Kaike Wan <kaike.wan@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit ab57588 upstream. ccw console is created early in start_kernel and used before css is initialized or ccw console subchannel is registered. Until then console subchannel does not have a parent. For that reason assume subchannels with no parent are not pseudo subchannels. This fixes the following kasan finding: BUG: KASAN: global-out-of-bounds in sch_is_pseudo_sch+0x8e/0x98 Read of size 8 at addr 00000000000005e8 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc8-07370-g6ac43dd12538 #2 Hardware name: IBM 2964 NC9 702 (z/VM 6.4.0) Call Trace: ([<000000000012cd76>] show_stack+0x14e/0x1e0) [<0000000001f7fb44>] dump_stack+0x1a4/0x1f8 [<00000000007d7afc>] print_address_description+0x64/0x3c8 [<00000000007d75f6>] __kasan_report+0x14e/0x180 [<00000000018a2986>] sch_is_pseudo_sch+0x8e/0x98 [<000000000189b950>] cio_enable_subchannel+0x1d0/0x510 [<00000000018cac7c>] ccw_device_recognition+0x12c/0x188 [<0000000002ceb1a8>] ccw_device_enable_console+0x138/0x340 [<0000000002cf1cbe>] con3215_init+0x25e/0x300 [<0000000002c8770a>] console_init+0x68a/0x9b8 [<0000000002c6a3d6>] start_kernel+0x4fe/0x728 [<0000000000100070>] startup_continue+0x70/0xd0 Cc: stable@vger.kernel.org Reviewed-by: Sebastian Ott <sebott@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 443f2d5 upstream. Observe a segmentation fault when 'perf stat' is asked to repeat forever with the interval option. Without fix: # perf stat -r 0 -I 5000 -e cycles -a sleep 10 # time counts unit events 5.000211692 3,13,89,82,34,157 cycles 10.000380119 1,53,98,52,22,294 cycles 10.040467280 17,16,79,265 cycles Segmentation fault This problem was only observed when we use forever option aka -r 0 and works with limited repeats. Calling print_counter with ts being set to NULL, is not a correct option when interval is set. Hence avoid print_counter(NULL,..) if interval is set. With fix: # perf stat -r 0 -I 5000 -e cycles -a sleep 10 # time counts unit events 5.019866622 3,15,14,43,08,697 cycles 10.039865756 3,15,16,31,95,261 cycles 10.059950628 1,26,05,47,158 cycles 5.009902655 3,14,52,62,33,932 cycles 10.019880228 3,14,52,22,89,154 cycles 10.030543876 66,90,18,333 cycles 5.009848281 3,14,51,98,25,437 cycles 10.029854402 3,15,14,93,04,918 cycles 5.009834177 3,14,51,95,92,316 cycles Committer notes: Did the 'git bisect' to find the cset introducing the problem to add the Fixes tag below, and at that time the problem reproduced as: (gdb) run stat -r0 -I500 sleep 1 <SNIP> Program received signal SIGSEGV, Segmentation fault. print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866 866 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, csv_sep); (gdb) bt #0 print_interval (prefix=prefix@entry=0x7fffffffc8d0 "", ts=ts@entry=0x0) at builtin-stat.c:866 #1 0x000000000041860a in print_counters (ts=ts@entry=0x0, argc=argc@entry=2, argv=argv@entry=0x7fffffffd640) at builtin-stat.c:938 #2 0x0000000000419a7f in cmd_stat (argc=2, argv=0x7fffffffd640, prefix=<optimized out>) at builtin-stat.c:1411 #3 0x000000000045c65a in run_builtin (p=p@entry=0x6291b8 <commands+216>, argc=argc@entry=5, argv=argv@entry=0x7fffffffd640) at perf.c:370 #4 0x000000000045c893 in handle_internal_command (argc=5, argv=0x7fffffffd640) at perf.c:429 #5 0x000000000045c8f1 in run_argv (argcp=argcp@entry=0x7fffffffd4ac, argv=argv@entry=0x7fffffffd4a0) at perf.c:473 #6 0x000000000045cac9 in main (argc=<optimized out>, argv=<optimized out>) at perf.c:588 (gdb) Mostly the same as just before this patch: Program received signal SIGSEGV, Segmentation fault. 0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964 964 sprintf(prefix, "%6lu.%09lu%s", ts->tv_sec, ts->tv_nsec, config->csv_sep); (gdb) bt #0 0x00000000005874a7 in print_interval (config=0xa1f2a0 <stat_config>, evlist=0xbc9b90, prefix=0x7fffffffd1c0 "`", ts=0x0) at util/stat-display.c:964 #1 0x0000000000588047 in perf_evlist__print_counters (evlist=0xbc9b90, config=0xa1f2a0 <stat_config>, _target=0xa1f0c0 <target>, ts=0x0, argc=2, argv=0x7fffffffd670) at util/stat-display.c:1172 #2 0x000000000045390f in print_counters (ts=0x0, argc=2, argv=0x7fffffffd670) at builtin-stat.c:656 #3 0x0000000000456bb5 in cmd_stat (argc=2, argv=0x7fffffffd670) at builtin-stat.c:1960 #4 0x00000000004dd2e0 in run_builtin (p=0xa30e00 <commands+288>, argc=5, argv=0x7fffffffd670) at perf.c:310 #5 0x00000000004dd54d in handle_internal_command (argc=5, argv=0x7fffffffd670) at perf.c:362 #6 0x00000000004dd694 in run_argv (argcp=0x7fffffffd4cc, argv=0x7fffffffd4c0) at perf.c:406 #7 0x00000000004dda11 in main (argc=5, argv=0x7fffffffd670) at perf.c:531 (gdb) Fixes: d4f63a4 ("perf stat: Introduce print_counters function") Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # v4.2+ Link: http://lore.kernel.org/lkml/20190904094738.9558-3-srikar@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit c784be4 ] The calls to arch_add_memory()/arch_remove_memory() are always made with the read-side cpu_hotplug_lock acquired via memory_hotplug_begin(). On pSeries, arch_add_memory()/arch_remove_memory() eventually call resize_hpt() which in turn calls stop_machine() which acquires the read-side cpu_hotplug_lock again, thereby resulting in the recursive acquisition of this lock. In the absence of CONFIG_PROVE_LOCKING, we hadn't observed a system lockup during a memory hotplug operation because cpus_read_lock() is a per-cpu rwsem read, which, in the fast-path (in the absence of the writer, which in our case is a CPU-hotplug operation) simply increments the read_count on the semaphore. Thus a recursive read in the fast-path doesn't cause any problems. However, we can hit this problem in practice if there is a concurrent CPU-Hotplug operation in progress which is waiting to acquire the write-side of the lock. This will cause the second recursive read to block until the writer finishes. While the writer is blocked since the first read holds the lock. Thus both the reader as well as the writers fail to make any progress thereby blocking both CPU-Hotplug as well as Memory Hotplug operations. Memory-Hotplug CPU-Hotplug CPU 0 CPU 1 ------ ------ 1. down_read(cpu_hotplug_lock.rw_sem) [memory_hotplug_begin] 2. down_write(cpu_hotplug_lock.rw_sem) [cpu_up/cpu_down] 3. down_read(cpu_hotplug_lock.rw_sem) [stop_machine()] Lockdep complains as follows in these code-paths. swapper/0/1 is trying to acquire lock: (____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: stop_machine+0x2c/0x60 but task is already holding lock: (____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: mem_hotplug_begin+0x20/0x50 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(cpu_hotplug_lock.rw_sem); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by swapper/0/1: #0: (____ptrval____) (&dev->mutex){....}, at: __driver_attach+0x12c/0x1b0 #1: (____ptrval____) (cpu_hotplug_lock.rw_sem){++++}, at: mem_hotplug_begin+0x20/0x50 #2: (____ptrval____) (mem_hotplug_lock.rw_sem){++++}, at: percpu_down_write+0x54/0x1a0 stack backtrace: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.0.0-rc5-58373-gbc99402235f3-dirty #166 Call Trace: dump_stack+0xe8/0x164 (unreliable) __lock_acquire+0x1110/0x1c70 lock_acquire+0x240/0x290 cpus_read_lock+0x64/0xf0 stop_machine+0x2c/0x60 pseries_lpar_resize_hpt+0x19c/0x2c0 resize_hpt_for_hotplug+0x70/0xd0 arch_add_memory+0x58/0xfc devm_memremap_pages+0x5e8/0x8f0 pmem_attach_disk+0x764/0x830 nvdimm_bus_probe+0x118/0x240 really_probe+0x230/0x4b0 driver_probe_device+0x16c/0x1e0 __driver_attach+0x148/0x1b0 bus_for_each_dev+0x90/0x130 driver_attach+0x34/0x50 bus_add_driver+0x1a8/0x360 driver_register+0x108/0x170 __nd_driver_register+0xd0/0xf0 nd_pmem_driver_init+0x34/0x48 do_one_initcall+0x1e0/0x45c kernel_init_freeable+0x540/0x64c kernel_init+0x2c/0x160 ret_from_kernel_thread+0x5c/0x68 Fix this issue by 1) Requiring all the calls to pseries_lpar_resize_hpt() be made with cpu_hotplug_lock held. 2) In pseries_lpar_resize_hpt() invoke stop_machine_cpuslocked() as a consequence of 1) 3) To satisfy 1), in hpt_order_set(), call mmu_hash_ops.resize_hpt() with cpu_hotplug_lock held. Fixes: dbcf929 ("powerpc/pseries: Add support for hash table resizing") Cc: stable@vger.kernel.org # v4.11+ Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1557906352-29048-1-git-send-email-ego@linux.vnet.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit b9023b9 ] When a cpu requests broadcasting, before starting the tick broadcast hrtimer, bc_set_next() checks if the timer callback (bc_handler) is active using hrtimer_try_to_cancel(). But hrtimer_try_to_cancel() does not provide the required synchronization when the callback is active on other core. The callback could have already executed tick_handle_oneshot_broadcast() and could have also returned. But still there is a small time window where the hrtimer_try_to_cancel() returns -1. In that case bc_set_next() returns without doing anything, but the next_event of the tick broadcast clock device is already set to a timeout value. In the race condition diagram below, CPU #1 is running the timer callback and CPU #2 is entering idle state and so calls bc_set_next(). In the worst case, the next_event will contain an expiry time, but the hrtimer will not be started which happens when the racing callback returns HRTIMER_NORESTART. The hrtimer might never recover if all further requests from the CPUs to subscribe to tick broadcast have timeout greater than the next_event of tick broadcast clock device. This leads to cascading of failures and finally noticed as rcu stall warnings Here is a depiction of the race condition CPU #1 (Running timer callback) CPU #2 (Enter idle and subscribe to tick broadcast) --------------------- --------------------- __run_hrtimer() tick_broadcast_enter() bc_handler() __tick_broadcast_oneshot_control() tick_handle_oneshot_broadcast() raw_spin_lock(&tick_broadcast_lock); dev->next_event = KTIME_MAX; //wait for tick_broadcast_lock //next_event for tick broadcast clock set to KTIME_MAX since no other cores subscribed to tick broadcasting raw_spin_unlock(&tick_broadcast_lock); if (dev->next_event == KTIME_MAX) return HRTIMER_NORESTART // callback function exits without restarting the hrtimer //tick_broadcast_lock acquired raw_spin_lock(&tick_broadcast_lock); tick_broadcast_set_event() clockevents_program_event() dev->next_event = expires; bc_set_next() hrtimer_try_to_cancel() //returns -1 since the timer callback is active. Exits without restarting the timer cpu_base->running = NULL; The comment that hrtimer cannot be armed from within the callback is wrong. It is fine to start the hrtimer from within the callback. Also it is safe to start the hrtimer from the enter/exit idle code while the broadcast handler is active. The enter/exit idle code and the broadcast handler are synchronized using tick_broadcast_lock. So there is no need for the existing try to cancel logic. All this can be removed which will eliminate the race condition as well. Fixes: 5d1638a ("tick: Introduce hrtimer based broadcast") Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190926135101.12102-2-balasubramani_vivekanandan@mentor.com Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 0216234 ] We release wrong pointer on error path in cpu_cache_level__read function, leading to segfault: (gdb) r record ls Starting program: /root/perf/tools/perf/perf record ls ... [ perf record: Woken up 1 times to write data ] double free or corruption (out) Thread 1 "perf" received signal SIGABRT, Aborted. 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6 (gdb) bt #0 0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6 #1 0x00007ffff7443bac in abort () from /lib64/power9/libc.so.6 #2 0x00007ffff74af8bc in __libc_message () from /lib64/power9/libc.so.6 #3 0x00007ffff74b92b8 in malloc_printerr () from /lib64/power9/libc.so.6 #4 0x00007ffff74bb874 in _int_free () from /lib64/power9/libc.so.6 #5 0x0000000010271260 in __zfree (ptr=0x7fffffffa0b0) at ../../lib/zalloc.. #6 0x0000000010139340 in cpu_cache_level__read (cache=0x7fffffffa090, cac.. #7 0x0000000010143c90 in build_caches (cntp=0x7fffffffa118, size=<optimiz.. ... Releasing the proper pointer. Fixes: 720e98b ("perf tools: Add perf data cache feature") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org: # v4.6+ Link: http://lore.kernel.org/lkml/20190912105235.10689-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit f8659d6 upstream. Define the working variables to be unsigned long to be compatible with for_each_set_bit and change types as needed. While we are at it remove unused variables from a couple of functions. This was found because of the following KASAN warning: ================================================================== BUG: KASAN: stack-out-of-bounds in find_first_bit+0x19/0x70 Read of size 8 at addr ffff888362d778d0 by task kworker/u308:2/1889 CPU: 21 PID: 1889 Comm: kworker/u308:2 Tainted: G W 5.3.0-rc2-mm1+ #2 Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.02.04.0003.102320141138 10/23/2014 Workqueue: ib-comp-unb-wq ib_cq_poll_work [ib_core] Call Trace: dump_stack+0x9a/0xf0 ? find_first_bit+0x19/0x70 print_address_description+0x6c/0x332 ? find_first_bit+0x19/0x70 ? find_first_bit+0x19/0x70 __kasan_report.cold.6+0x1a/0x3b ? find_first_bit+0x19/0x70 kasan_report+0xe/0x12 find_first_bit+0x19/0x70 pma_get_opa_portstatus+0x5cc/0xa80 [hfi1] ? ret_from_fork+0x3a/0x50 ? pma_get_opa_port_ectrs+0x200/0x200 [hfi1] ? stack_trace_consume_entry+0x80/0x80 hfi1_process_mad+0x39b/0x26c0 [hfi1] ? __lock_acquire+0x65e/0x21b0 ? clear_linkup_counters+0xb0/0xb0 [hfi1] ? check_chain_key+0x1d7/0x2e0 ? lock_downgrade+0x3a0/0x3a0 ? match_held_lock+0x2e/0x250 ib_mad_recv_done+0x698/0x15e0 [ib_core] ? clear_linkup_counters+0xb0/0xb0 [hfi1] ? ib_mad_send_done+0xc80/0xc80 [ib_core] ? mark_held_locks+0x79/0xa0 ? _raw_spin_unlock_irqrestore+0x44/0x60 ? rvt_poll_cq+0x1e1/0x340 [rdmavt] __ib_process_cq+0x97/0x100 [ib_core] ib_cq_poll_work+0x31/0xb0 [ib_core] process_one_work+0x4ee/0xa00 ? pwq_dec_nr_in_flight+0x110/0x110 ? do_raw_spin_lock+0x113/0x1d0 worker_thread+0x57/0x5a0 ? process_one_work+0xa00/0xa00 kthread+0x1bb/0x1e0 ? kthread_create_on_node+0xc0/0xc0 ret_from_fork+0x3a/0x50 The buggy address belongs to the page: page:ffffea000d8b5dc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x17ffffc0000000() raw: 0017ffffc0000000 0000000000000000 ffffea000d8b5dc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected addr ffff888362d778d0 is located in stack of task kworker/u308:2/1889 at offset 32 in frame: pma_get_opa_portstatus+0x0/0xa80 [hfi1] this frame has 1 object: [32, 36) 'vl_select_mask' Memory state around the buggy address: ffff888362d77780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888362d77800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888362d77880: 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 00 00 ^ ffff888362d77900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888362d77980: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 ================================================================== Cc: <stable@vger.kernel.org> Fixes: 7724105 ("IB/hfi1: add driver files") Link: https://lore.kernel.org/r/20190911113053.126040.47327.stgit@awfm-01.aw.intel.com Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Kaike Wan <kaike.wan@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit f8659d6 upstream. Define the working variables to be unsigned long to be compatible with for_each_set_bit and change types as needed. While we are at it remove unused variables from a couple of functions. This was found because of the following KASAN warning: ================================================================== BUG: KASAN: stack-out-of-bounds in find_first_bit+0x19/0x70 Read of size 8 at addr ffff888362d778d0 by task kworker/u308:2/1889 CPU: 21 PID: 1889 Comm: kworker/u308:2 Tainted: G W 5.3.0-rc2-mm1+ #2 Hardware name: Intel Corporation W2600CR/W2600CR, BIOS SE5C600.86B.02.04.0003.102320141138 10/23/2014 Workqueue: ib-comp-unb-wq ib_cq_poll_work [ib_core] Call Trace: dump_stack+0x9a/0xf0 ? find_first_bit+0x19/0x70 print_address_description+0x6c/0x332 ? find_first_bit+0x19/0x70 ? find_first_bit+0x19/0x70 __kasan_report.cold.6+0x1a/0x3b ? find_first_bit+0x19/0x70 kasan_report+0xe/0x12 find_first_bit+0x19/0x70 pma_get_opa_portstatus+0x5cc/0xa80 [hfi1] ? ret_from_fork+0x3a/0x50 ? pma_get_opa_port_ectrs+0x200/0x200 [hfi1] ? stack_trace_consume_entry+0x80/0x80 hfi1_process_mad+0x39b/0x26c0 [hfi1] ? __lock_acquire+0x65e/0x21b0 ? clear_linkup_counters+0xb0/0xb0 [hfi1] ? check_chain_key+0x1d7/0x2e0 ? lock_downgrade+0x3a0/0x3a0 ? match_held_lock+0x2e/0x250 ib_mad_recv_done+0x698/0x15e0 [ib_core] ? clear_linkup_counters+0xb0/0xb0 [hfi1] ? ib_mad_send_done+0xc80/0xc80 [ib_core] ? mark_held_locks+0x79/0xa0 ? _raw_spin_unlock_irqrestore+0x44/0x60 ? rvt_poll_cq+0x1e1/0x340 [rdmavt] __ib_process_cq+0x97/0x100 [ib_core] ib_cq_poll_work+0x31/0xb0 [ib_core] process_one_work+0x4ee/0xa00 ? pwq_dec_nr_in_flight+0x110/0x110 ? do_raw_spin_lock+0x113/0x1d0 worker_thread+0x57/0x5a0 ? process_one_work+0xa00/0xa00 kthread+0x1bb/0x1e0 ? kthread_create_on_node+0xc0/0xc0 ret_from_fork+0x3a/0x50 The buggy address belongs to the page: page:ffffea000d8b5dc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x17ffffc0000000() raw: 0017ffffc0000000 0000000000000000 ffffea000d8b5dc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected addr ffff888362d778d0 is located in stack of task kworker/u308:2/1889 at offset 32 in frame: pma_get_opa_portstatus+0x0/0xa80 [hfi1] this frame has 1 object: [32, 36) 'vl_select_mask' Memory state around the buggy address: ffff888362d77780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888362d77800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888362d77880: 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 00 00 ^ ffff888362d77900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888362d77980: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 ================================================================== Cc: <stable@vger.kernel.org> Fixes: 7724105 ("IB/hfi1: add driver files") Link: https://lore.kernel.org/r/20190911113053.126040.47327.stgit@awfm-01.aw.intel.com Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Kaike Wan <kaike.wan@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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All bonding device has same lockdep key and subclass is initialized with
nest_level.
But actual nest_level value can be changed when a lower device is attached.
And at this moment, the subclass should be updated but it seems to be
unsafe.
So this patch makes bonding use dynamic lockdep key instead of the
subclass.
Test commands:
ip link add bond0 type bond
for i in {1..5}
do
let A=$i-1
ip link add bond$i type bond
ip link set bond$i master bond$A
done
ip link set bond5 master bond0
Splat looks like:
[ 307.992912] WARNING: possible recursive locking detected
[ 307.993656] 5.4.0-rc3+ #96 Tainted: G W
[ 307.994367] --------------------------------------------
[ 307.995092] ip/761 is trying to acquire lock:
[ 307.995710] ffff8880513aac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[ 307.997045]
but task is already holding lock:
[ 307.997923] ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[ 307.999215]
other info that might help us debug this:
[ 308.000251] Possible unsafe locking scenario:
[ 308.001137] CPU0
[ 308.001533] ----
[ 308.001915] lock(&(&bond->stats_lock)->rlock#2/2);
[ 308.002609] lock(&(&bond->stats_lock)->rlock#2/2);
[ 308.003302]
*** DEADLOCK ***
[ 308.004310] May be due to missing lock nesting notation
[ 308.005319] 3 locks held by ip/761:
[ 308.005830] #0: ffffffff9fcc42b0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0
[ 308.006894] #1: ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[ 308.008243] #2: ffffffff9f9219c0 (rcu_read_lock){....}, at: bond_get_stats+0x9f/0x500 [bonding]
[ 308.009422]
stack backtrace:
[ 308.010124] CPU: 0 PID: 761 Comm: ip Tainted: G W 5.4.0-rc3+ #96
[ 308.011097] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 308.012179] Call Trace:
[ 308.012601] dump_stack+0x7c/0xbb
[ 308.013089] __lock_acquire+0x269d/0x3de0
[ 308.013669] ? register_lock_class+0x14d0/0x14d0
[ 308.014318] lock_acquire+0x164/0x3b0
[ 308.014858] ? bond_get_stats+0xb8/0x500 [bonding]
[ 308.015520] _raw_spin_lock_nested+0x2e/0x60
[ 308.016129] ? bond_get_stats+0xb8/0x500 [bonding]
[ 308.017215] bond_get_stats+0xb8/0x500 [bonding]
[ 308.018454] ? bond_arp_rcv+0xf10/0xf10 [bonding]
[ 308.019710] ? rcu_read_lock_held+0x90/0xa0
[ 308.020605] ? rcu_read_lock_sched_held+0xc0/0xc0
[ 308.021286] ? bond_get_stats+0x9f/0x500 [bonding]
[ 308.021953] dev_get_stats+0x1ec/0x270
[ 308.022508] bond_get_stats+0x1d1/0x500 [bonding]
Fixes: d3fff6c ("net: add netdev_lockdep_set_classes() helper")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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commit 2190168 upstream. On excessive bit errors for the FCP channel ingress fibre path, the channel notifies us. Previously, we only emitted a kernel message and a trace record. Since performance can become suboptimal with I/O timeouts due to bit errors, we now stop using an FCP device by default on channel notification so multipath on top can timely failover to other paths. A new module parameter zfcp.ber_stop can be used to get zfcp old behavior. User explanation of new kernel message: * Description: * The FCP channel reported that its bit error threshold has been exceeded. * These errors might result from a problem with the physical components * of the local fibre link into the FCP channel. * The problem might be damage or malfunction of the cable or * cable connection between the FCP channel and * the adjacent fabric switch port or the point-to-point peer. * Find details about the errors in the HBA trace for the FCP device. * The zfcp device driver closed down the FCP device * to limit the performance impact from possible I/O command timeouts. * User action: * Check for problems on the local fibre link, ensure that fibre optics are * clean and functional, and all cables are properly plugged. * After the repair action, you can manually recover the FCP device by * writing "0" into its "failed" sysfs attribute. * If recovery through sysfs is not possible, set the CHPID of the device * offline and back online on the service element. Fixes: 1da177e ("Linux-2.6.12-rc2") Cc: <stable@vger.kernel.org> #2.6.30+ Link: https://lore.kernel.org/r/20191001104949.42810-1-maier@linux.ibm.com Reviewed-by: Jens Remus <jremus@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Steffen Maier <maier@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 4f2a572 upstream. Daniel Vetter uncovered a nasty cycle in using the mmu-notifiers to invalidate userptr objects which also happen to be pulled into GGTT mmaps. That is when we unbind the userptr object (on mmu invalidation), we revoke all CPU mmaps, which may then recurse into mmu invalidation. We looked for ways of breaking the cycle, but the revocation on invalidation is required and cannot be avoided. The only solution we could see was to not allow such GGTT bindings of userptr objects in the first place. In practice, no one really wants to use a GGTT mmapping of a CPU pointer... Just before Daniel's explosive lockdep patches land in v5.4-rc1, we got a genuine blip from CI: <4>[ 246.793958] ====================================================== <4>[ 246.793972] WARNING: possible circular locking dependency detected <4>[ 246.793989] 5.3.0-gbd6c56f50d15-drmtip_372+ #1 Tainted: G U <4>[ 246.794003] ------------------------------------------------------ <4>[ 246.794017] kswapd0/145 is trying to acquire lock: <4>[ 246.794030] 000000003f565be6 (&dev->struct_mutex/1){+.+.}, at: userptr_mn_invalidate_range_start+0x18f/0x220 [i915] <4>[ 246.794250] but task is already holding lock: <4>[ 246.794263] 000000001799cef9 (&anon_vma->rwsem){++++}, at: page_lock_anon_vma_read+0xe6/0x2a0 <4>[ 246.794291] which lock already depends on the new lock. <4>[ 246.794307] the existing dependency chain (in reverse order) is: <4>[ 246.794322] -> #3 (&anon_vma->rwsem){++++}: <4>[ 246.794344] down_write+0x33/0x70 <4>[ 246.794357] __vma_adjust+0x3d9/0x7b0 <4>[ 246.794370] __split_vma+0x16a/0x180 <4>[ 246.794385] mprotect_fixup+0x2a5/0x320 <4>[ 246.794399] do_mprotect_pkey+0x208/0x2e0 <4>[ 246.794413] __x64_sys_mprotect+0x16/0x20 <4>[ 246.794429] do_syscall_64+0x55/0x1c0 <4>[ 246.794443] entry_SYSCALL_64_after_hwframe+0x49/0xbe <4>[ 246.794456] -> #2 (&mapping->i_mmap_rwsem){++++}: <4>[ 246.794478] down_write+0x33/0x70 <4>[ 246.794493] unmap_mapping_pages+0x48/0x130 <4>[ 246.794519] i915_vma_revoke_mmap+0x81/0x1b0 [i915] <4>[ 246.794519] i915_vma_unbind+0x11d/0x4a0 [i915] <4>[ 246.794519] i915_vma_destroy+0x31/0x300 [i915] <4>[ 246.794519] __i915_gem_free_objects+0xb8/0x4b0 [i915] <4>[ 246.794519] drm_file_free.part.0+0x1e6/0x290 <4>[ 246.794519] drm_release+0xa6/0xe0 <4>[ 246.794519] __fput+0xc2/0x250 <4>[ 246.794519] task_work_run+0x82/0xb0 <4>[ 246.794519] do_exit+0x35b/0xdb0 <4>[ 246.794519] do_group_exit+0x34/0xb0 <4>[ 246.794519] __x64_sys_exit_group+0xf/0x10 <4>[ 246.794519] do_syscall_64+0x55/0x1c0 <4>[ 246.794519] entry_SYSCALL_64_after_hwframe+0x49/0xbe <4>[ 246.794519] -> #1 (&vm->mutex){+.+.}: <4>[ 246.794519] i915_gem_shrinker_taints_mutex+0x6d/0xe0 [i915] <4>[ 246.794519] i915_address_space_init+0x9f/0x160 [i915] <4>[ 246.794519] i915_ggtt_init_hw+0x55/0x170 [i915] <4>[ 246.794519] i915_driver_probe+0xc9f/0x1620 [i915] <4>[ 246.794519] i915_pci_probe+0x43/0x1b0 [i915] <4>[ 246.794519] pci_device_probe+0x9e/0x120 <4>[ 246.794519] really_probe+0xea/0x3d0 <4>[ 246.794519] driver_probe_device+0x10b/0x120 <4>[ 246.794519] device_driver_attach+0x4a/0x50 <4>[ 246.794519] __driver_attach+0x97/0x130 <4>[ 246.794519] bus_for_each_dev+0x74/0xc0 <4>[ 246.794519] bus_add_driver+0x13f/0x210 <4>[ 246.794519] driver_register+0x56/0xe0 <4>[ 246.794519] do_one_initcall+0x58/0x300 <4>[ 246.794519] do_init_module+0x56/0x1f6 <4>[ 246.794519] load_module+0x25bd/0x2a40 <4>[ 246.794519] __se_sys_finit_module+0xd3/0xf0 <4>[ 246.794519] do_syscall_64+0x55/0x1c0 <4>[ 246.794519] entry_SYSCALL_64_after_hwframe+0x49/0xbe <4>[ 246.794519] -> #0 (&dev->struct_mutex/1){+.+.}: <4>[ 246.794519] __lock_acquire+0x15d8/0x1e90 <4>[ 246.794519] lock_acquire+0xa6/0x1c0 <4>[ 246.794519] __mutex_lock+0x9d/0x9b0 <4>[ 246.794519] userptr_mn_invalidate_range_start+0x18f/0x220 [i915] <4>[ 246.794519] __mmu_notifier_invalidate_range_start+0x85/0x110 <4>[ 246.794519] try_to_unmap_one+0x76b/0x860 <4>[ 246.794519] rmap_walk_anon+0x104/0x280 <4>[ 246.794519] try_to_unmap+0xc0/0xf0 <4>[ 246.794519] shrink_page_list+0x561/0xc10 <4>[ 246.794519] shrink_inactive_list+0x220/0x440 <4>[ 246.794519] shrink_node_memcg+0x36e/0x740 <4>[ 246.794519] shrink_node+0xcb/0x490 <4>[ 246.794519] balance_pgdat+0x241/0x580 <4>[ 246.794519] kswapd+0x16c/0x530 <4>[ 246.794519] kthread+0x119/0x130 <4>[ 246.794519] ret_from_fork+0x24/0x50 <4>[ 246.794519] other info that might help us debug this: <4>[ 246.794519] Chain exists of: &dev->struct_mutex/1 --> &mapping->i_mmap_rwsem --> &anon_vma->rwsem <4>[ 246.794519] Possible unsafe locking scenario: <4>[ 246.794519] CPU0 CPU1 <4>[ 246.794519] ---- ---- <4>[ 246.794519] lock(&anon_vma->rwsem); <4>[ 246.794519] lock(&mapping->i_mmap_rwsem); <4>[ 246.794519] lock(&anon_vma->rwsem); <4>[ 246.794519] lock(&dev->struct_mutex/1); <4>[ 246.794519] *** DEADLOCK *** v2: Say no to mmap_ioctl Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111744 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111870 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: stable@vger.kernel.org Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190928082546.3473-1-chris@chris-wilson.co.uk (cherry picked from commit a431174) Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit e4f8e51 upstream. A long time ago we fixed a similar deadlock in show_slab_objects() [1]. However, it is apparently due to the commits like 01fb58b ("slab: remove synchronous synchronize_sched() from memcg cache deactivation path") and 03afc0e ("slab: get_online_mems for kmem_cache_{create,destroy,shrink}"), this kind of deadlock is back by just reading files in /sys/kernel/slab which will generate a lockdep splat below. Since the "mem_hotplug_lock" here is only to obtain a stable online node mask while racing with NUMA node hotplug, in the worst case, the results may me miscalculated while doing NUMA node hotplug, but they shall be corrected by later reads of the same files. WARNING: possible circular locking dependency detected ------------------------------------------------------ cat/5224 is trying to acquire lock: ffff900012ac3120 (mem_hotplug_lock.rw_sem){++++}, at: show_slab_objects+0x94/0x3a8 but task is already holding lock: b8ff009693eee398 (kn->count#45){++++}, at: kernfs_seq_start+0x44/0xf0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (kn->count#45){++++}: lock_acquire+0x31c/0x360 __kernfs_remove+0x290/0x490 kernfs_remove+0x30/0x44 sysfs_remove_dir+0x70/0x88 kobject_del+0x50/0xb0 sysfs_slab_unlink+0x2c/0x38 shutdown_cache+0xa0/0xf0 kmemcg_cache_shutdown_fn+0x1c/0x34 kmemcg_workfn+0x44/0x64 process_one_work+0x4f4/0x950 worker_thread+0x390/0x4bc kthread+0x1cc/0x1e8 ret_from_fork+0x10/0x18 -> #1 (slab_mutex){+.+.}: lock_acquire+0x31c/0x360 __mutex_lock_common+0x16c/0xf78 mutex_lock_nested+0x40/0x50 memcg_create_kmem_cache+0x38/0x16c memcg_kmem_cache_create_func+0x3c/0x70 process_one_work+0x4f4/0x950 worker_thread+0x390/0x4bc kthread+0x1cc/0x1e8 ret_from_fork+0x10/0x18 -> #0 (mem_hotplug_lock.rw_sem){++++}: validate_chain+0xd10/0x2bcc __lock_acquire+0x7f4/0xb8c lock_acquire+0x31c/0x360 get_online_mems+0x54/0x150 show_slab_objects+0x94/0x3a8 total_objects_show+0x28/0x34 slab_attr_show+0x38/0x54 sysfs_kf_seq_show+0x198/0x2d4 kernfs_seq_show+0xa4/0xcc seq_read+0x30c/0x8a8 kernfs_fop_read+0xa8/0x314 __vfs_read+0x88/0x20c vfs_read+0xd8/0x10c ksys_read+0xb0/0x120 __arm64_sys_read+0x54/0x88 el0_svc_handler+0x170/0x240 el0_svc+0x8/0xc other info that might help us debug this: Chain exists of: mem_hotplug_lock.rw_sem --> slab_mutex --> kn->count#45 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(kn->count#45); lock(slab_mutex); lock(kn->count#45); lock(mem_hotplug_lock.rw_sem); *** DEADLOCK *** 3 locks held by cat/5224: #0: 9eff00095b14b2a0 (&p->lock){+.+.}, at: seq_read+0x4c/0x8a8 #1: 0eff008997041480 (&of->mutex){+.+.}, at: kernfs_seq_start+0x34/0xf0 #2: b8ff009693eee398 (kn->count#45){++++}, at: kernfs_seq_start+0x44/0xf0 stack backtrace: Call trace: dump_backtrace+0x0/0x248 show_stack+0x20/0x2c dump_stack+0xd0/0x140 print_circular_bug+0x368/0x380 check_noncircular+0x248/0x250 validate_chain+0xd10/0x2bcc __lock_acquire+0x7f4/0xb8c lock_acquire+0x31c/0x360 get_online_mems+0x54/0x150 show_slab_objects+0x94/0x3a8 total_objects_show+0x28/0x34 slab_attr_show+0x38/0x54 sysfs_kf_seq_show+0x198/0x2d4 kernfs_seq_show+0xa4/0xcc seq_read+0x30c/0x8a8 kernfs_fop_read+0xa8/0x314 __vfs_read+0x88/0x20c vfs_read+0xd8/0x10c ksys_read+0xb0/0x120 __arm64_sys_read+0x54/0x88 el0_svc_handler+0x170/0x240 el0_svc+0x8/0xc I think it is important to mention that this doesn't expose the show_slab_objects to use-after-free. There is only a single path that might really race here and that is the slab hotplug notifier callback __kmem_cache_shrink (via slab_mem_going_offline_callback) but that path doesn't really destroy kmem_cache_node data structures. [1] http://lkml.iu.edu/hypermail/linux/kernel/1101.0/02850.html [akpm@linux-foundation.org: add comment explaining why we don't need mem_hotplug_lock] Link: http://lkml.kernel.org/r/1570192309-10132-1-git-send-email-cai@lca.pw Fixes: 01fb58b ("slab: remove synchronous synchronize_sched() from memcg cache deactivation path") Fixes: 03afc0e ("slab: get_online_mems for kmem_cache_{create,destroy,shrink}") Signed-off-by: Qian Cai <cai@lca.pw> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 2190168 upstream. On excessive bit errors for the FCP channel ingress fibre path, the channel notifies us. Previously, we only emitted a kernel message and a trace record. Since performance can become suboptimal with I/O timeouts due to bit errors, we now stop using an FCP device by default on channel notification so multipath on top can timely failover to other paths. A new module parameter zfcp.ber_stop can be used to get zfcp old behavior. User explanation of new kernel message: * Description: * The FCP channel reported that its bit error threshold has been exceeded. * These errors might result from a problem with the physical components * of the local fibre link into the FCP channel. * The problem might be damage or malfunction of the cable or * cable connection between the FCP channel and * the adjacent fabric switch port or the point-to-point peer. * Find details about the errors in the HBA trace for the FCP device. * The zfcp device driver closed down the FCP device * to limit the performance impact from possible I/O command timeouts. * User action: * Check for problems on the local fibre link, ensure that fibre optics are * clean and functional, and all cables are properly plugged. * After the repair action, you can manually recover the FCP device by * writing "0" into its "failed" sysfs attribute. * If recovery through sysfs is not possible, set the CHPID of the device * offline and back online on the service element. Fixes: 1da177e ("Linux-2.6.12-rc2") Cc: <stable@vger.kernel.org> #2.6.30+ Link: https://lore.kernel.org/r/20191001104949.42810-1-maier@linux.ibm.com Reviewed-by: Jens Remus <jremus@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Steffen Maier <maier@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit e4f8e51 upstream. A long time ago we fixed a similar deadlock in show_slab_objects() [1]. However, it is apparently due to the commits like 01fb58b ("slab: remove synchronous synchronize_sched() from memcg cache deactivation path") and 03afc0e ("slab: get_online_mems for kmem_cache_{create,destroy,shrink}"), this kind of deadlock is back by just reading files in /sys/kernel/slab which will generate a lockdep splat below. Since the "mem_hotplug_lock" here is only to obtain a stable online node mask while racing with NUMA node hotplug, in the worst case, the results may me miscalculated while doing NUMA node hotplug, but they shall be corrected by later reads of the same files. WARNING: possible circular locking dependency detected ------------------------------------------------------ cat/5224 is trying to acquire lock: ffff900012ac3120 (mem_hotplug_lock.rw_sem){++++}, at: show_slab_objects+0x94/0x3a8 but task is already holding lock: b8ff009693eee398 (kn->count#45){++++}, at: kernfs_seq_start+0x44/0xf0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (kn->count#45){++++}: lock_acquire+0x31c/0x360 __kernfs_remove+0x290/0x490 kernfs_remove+0x30/0x44 sysfs_remove_dir+0x70/0x88 kobject_del+0x50/0xb0 sysfs_slab_unlink+0x2c/0x38 shutdown_cache+0xa0/0xf0 kmemcg_cache_shutdown_fn+0x1c/0x34 kmemcg_workfn+0x44/0x64 process_one_work+0x4f4/0x950 worker_thread+0x390/0x4bc kthread+0x1cc/0x1e8 ret_from_fork+0x10/0x18 -> #1 (slab_mutex){+.+.}: lock_acquire+0x31c/0x360 __mutex_lock_common+0x16c/0xf78 mutex_lock_nested+0x40/0x50 memcg_create_kmem_cache+0x38/0x16c memcg_kmem_cache_create_func+0x3c/0x70 process_one_work+0x4f4/0x950 worker_thread+0x390/0x4bc kthread+0x1cc/0x1e8 ret_from_fork+0x10/0x18 -> #0 (mem_hotplug_lock.rw_sem){++++}: validate_chain+0xd10/0x2bcc __lock_acquire+0x7f4/0xb8c lock_acquire+0x31c/0x360 get_online_mems+0x54/0x150 show_slab_objects+0x94/0x3a8 total_objects_show+0x28/0x34 slab_attr_show+0x38/0x54 sysfs_kf_seq_show+0x198/0x2d4 kernfs_seq_show+0xa4/0xcc seq_read+0x30c/0x8a8 kernfs_fop_read+0xa8/0x314 __vfs_read+0x88/0x20c vfs_read+0xd8/0x10c ksys_read+0xb0/0x120 __arm64_sys_read+0x54/0x88 el0_svc_handler+0x170/0x240 el0_svc+0x8/0xc other info that might help us debug this: Chain exists of: mem_hotplug_lock.rw_sem --> slab_mutex --> kn->count#45 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(kn->count#45); lock(slab_mutex); lock(kn->count#45); lock(mem_hotplug_lock.rw_sem); *** DEADLOCK *** 3 locks held by cat/5224: #0: 9eff00095b14b2a0 (&p->lock){+.+.}, at: seq_read+0x4c/0x8a8 #1: 0eff008997041480 (&of->mutex){+.+.}, at: kernfs_seq_start+0x34/0xf0 #2: b8ff009693eee398 (kn->count#45){++++}, at: kernfs_seq_start+0x44/0xf0 stack backtrace: Call trace: dump_backtrace+0x0/0x248 show_stack+0x20/0x2c dump_stack+0xd0/0x140 print_circular_bug+0x368/0x380 check_noncircular+0x248/0x250 validate_chain+0xd10/0x2bcc __lock_acquire+0x7f4/0xb8c lock_acquire+0x31c/0x360 get_online_mems+0x54/0x150 show_slab_objects+0x94/0x3a8 total_objects_show+0x28/0x34 slab_attr_show+0x38/0x54 sysfs_kf_seq_show+0x198/0x2d4 kernfs_seq_show+0xa4/0xcc seq_read+0x30c/0x8a8 kernfs_fop_read+0xa8/0x314 __vfs_read+0x88/0x20c vfs_read+0xd8/0x10c ksys_read+0xb0/0x120 __arm64_sys_read+0x54/0x88 el0_svc_handler+0x170/0x240 el0_svc+0x8/0xc I think it is important to mention that this doesn't expose the show_slab_objects to use-after-free. There is only a single path that might really race here and that is the slab hotplug notifier callback __kmem_cache_shrink (via slab_mem_going_offline_callback) but that path doesn't really destroy kmem_cache_node data structures. [1] http://lkml.iu.edu/hypermail/linux/kernel/1101.0/02850.html [akpm@linux-foundation.org: add comment explaining why we don't need mem_hotplug_lock] Link: http://lkml.kernel.org/r/1570192309-10132-1-git-send-email-cai@lca.pw Fixes: 01fb58b ("slab: remove synchronous synchronize_sched() from memcg cache deactivation path") Fixes: 03afc0e ("slab: get_online_mems for kmem_cache_{create,destroy,shrink}") Signed-off-by: Qian Cai <cai@lca.pw> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When the extent tree is modified, it should be protected by inode cluster lock and ip_alloc_sem. The extent tree is accessed and modified in the ocfs2_prepare_inode_for_write, but isn't protected by ip_alloc_sem. The following is a case. The function ocfs2_fiemap is accessing the extent tree, which is modified at the same time. kernel BUG at fs/ocfs2/extent_map.c:475! invalid opcode: 0000 [#1] SMP Modules linked in: tun ocfs2 ocfs2_nodemanager configfs ocfs2_stackglue [...] CPU: 16 PID: 14047 Comm: o2info Not tainted 4.1.12-124.23.1.el6uek.x86_64 #2 Hardware name: Oracle Corporation ORACLE SERVER X7-2L/ASM, MB MECH, X7-2L, BIOS 42040600 10/19/2018 task: ffff88019487e200 ti: ffff88003daa4000 task.ti: ffff88003daa4000 RIP: ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2] Call Trace: ocfs2_fiemap+0x1e3/0x430 [ocfs2] do_vfs_ioctl+0x155/0x510 SyS_ioctl+0x81/0xa0 system_call_fastpath+0x18/0xd8 Code: 18 48 c7 c6 60 7f 65 a0 31 c0 bb e2 ff ff ff 48 8b 4a 40 48 8b 7a 28 48 c7 c2 78 2d 66 a0 e8 38 4f 05 00 e9 28 fe ff ff 0f 1f 00 <0f> 0b 66 0f 1f 44 00 00 bb 86 ff ff ff e9 13 fe ff ff 66 0f 1f RIP ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2] ---[ end trace c8aa0c8180e869dc ]--- Kernel panic - not syncing: Fatal exception Kernel Offset: disabled This issue can be reproduced every week in a production environment. This issue is related to the usage mode. If others use ocfs2 in this mode, the kernel will panic frequently. [akpm@linux-foundation.org: coding style fixes] [Fix new warning due to unused function by removing said function - Linus ] Link: http://lkml.kernel.org/r/1568772175-2906-2-git-send-email-sunny.s.zhang@oracle.com Signed-off-by: Shuning Zhang <sunny.s.zhang@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Gang He <ghe@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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[ Upstream commit b66f31e ] This patch fixes the lock inversion complaint: ============================================ WARNING: possible recursive locking detected 5.3.0-rc7-dbg+ #1 Not tainted -------------------------------------------- kworker/u16:6/171 is trying to acquire lock: 00000000035c6e6c (&id_priv->handler_mutex){+.+.}, at: rdma_destroy_id+0x78/0x4a0 [rdma_cm] but task is already holding lock: 00000000bc7c307d (&id_priv->handler_mutex){+.+.}, at: iw_conn_req_handler+0x151/0x680 [rdma_cm] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&id_priv->handler_mutex); lock(&id_priv->handler_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kworker/u16:6/171: #0: 00000000e2eaa773 ((wq_completion)iw_cm_wq){+.+.}, at: process_one_work+0x472/0xac0 #1: 000000001efd357b ((work_completion)(&work->work)#3){+.+.}, at: process_one_work+0x476/0xac0 #2: 00000000bc7c307d (&id_priv->handler_mutex){+.+.}, at: iw_conn_req_handler+0x151/0x680 [rdma_cm] stack backtrace: CPU: 3 PID: 171 Comm: kworker/u16:6 Not tainted 5.3.0-rc7-dbg+ #1 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: iw_cm_wq cm_work_handler [iw_cm] Call Trace: dump_stack+0x8a/0xd6 __lock_acquire.cold+0xe1/0x24d lock_acquire+0x106/0x240 __mutex_lock+0x12e/0xcb0 mutex_lock_nested+0x1f/0x30 rdma_destroy_id+0x78/0x4a0 [rdma_cm] iw_conn_req_handler+0x5c9/0x680 [rdma_cm] cm_work_handler+0xe62/0x1100 [iw_cm] process_one_work+0x56d/0xac0 worker_thread+0x7a/0x5d0 kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 This is not a bug as there are actually two lock classes here. Link: https://lore.kernel.org/r/20190930231707.48259-3-bvanassche@acm.org Fixes: de910bd ("RDMA/cma: Simplify locking needed for serialization of callbacks") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit abdd3d0 upstream. Original version of g920_get_config() contained two kind of actions: 1. Device specific communication to query/set some parameters which requires active communication channel with the device, or, put in other way, for the call to be sandwiched between hid_device_io_start() and hid_device_io_stop(). 2. Input subsystem specific FF controller initialization which, in order to access a valid 'struct hid_input' via 'hid->inputs.next', requires claimed hidinput which means be executed after the call to hid_hw_start() with connect_mask containing HID_CONNECT_HIDINPUT. Location of g920_get_config() can only fulfill requirements for #1 and not #2, which might result in following backtrace: [ 88.312258] logitech-hidpp-device 0003:046D:C262.0005: HID++ 4.2 device connected. [ 88.320298] BUG: kernel NULL pointer dereference, address: 0000000000000018 [ 88.320304] #PF: supervisor read access in kernel mode [ 88.320307] #PF: error_code(0x0000) - not-present page [ 88.320309] PGD 0 P4D 0 [ 88.320315] Oops: 0000 [#1] SMP PTI [ 88.320320] CPU: 1 PID: 3080 Comm: systemd-udevd Not tainted 5.4.0-rc1+ #31 [ 88.320322] Hardware name: Apple Inc. MacBookPro11,1/Mac-189A3D4F975D5FFC, BIOS 149.0.0.0.0 09/17/2018 [ 88.320334] RIP: 0010:hidpp_probe+0x61f/0x948 [hid_logitech_hidpp] [ 88.320338] Code: 81 00 00 48 89 ef e8 f0 d6 ff ff 41 89 c6 85 c0 75 b5 0f b6 44 24 28 48 8b 5d 00 88 44 24 1e 89 44 24 0c 48 8b 83 18 1c 00 00 <48> 8b 48 18 48 8b 83 10 19 00 00 48 8b 40 40 48 89 0c 24 0f b7 80 [ 88.320341] RSP: 0018:ffffb0a6824aba68 EFLAGS: 00010246 [ 88.320345] RAX: 0000000000000000 RBX: ffff93a50756e000 RCX: 0000000000010408 [ 88.320347] RDX: 0000000000000000 RSI: ffff93a51f0ad0a0 RDI: 000000000002d0a0 [ 88.320350] RBP: ffff93a50416da28 R08: ffff93a50416da70 R09: ffff93a50416da70 [ 88.320352] R10: 000000148ae9e60c R11: 00000000000f1525 R12: ffff93a50756e000 [ 88.320354] R13: ffff93a50756f8d0 R14: 0000000000000000 R15: ffff93a50756fc38 [ 88.320358] FS: 00007f8d8c1e0940(0000) GS:ffff93a51f080000(0000) knlGS:0000000000000000 [ 88.320361] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 88.320363] CR2: 0000000000000018 CR3: 00000003996d8003 CR4: 00000000001606e0 [ 88.320366] Call Trace: [ 88.320377] ? _cond_resched+0x15/0x30 [ 88.320387] ? create_pinctrl+0x2f/0x3c0 [ 88.320393] ? kernfs_link_sibling+0x94/0xe0 [ 88.320398] ? _cond_resched+0x15/0x30 [ 88.320402] ? kernfs_activate+0x5f/0x80 [ 88.320406] ? kernfs_add_one+0xe2/0x130 [ 88.320411] hid_device_probe+0x106/0x170 [ 88.320419] really_probe+0x147/0x3c0 [ 88.320424] driver_probe_device+0xb6/0x100 [ 88.320428] device_driver_attach+0x53/0x60 [ 88.320433] __driver_attach+0x8a/0x150 [ 88.320437] ? device_driver_attach+0x60/0x60 [ 88.320440] bus_for_each_dev+0x78/0xc0 [ 88.320445] bus_add_driver+0x14d/0x1f0 [ 88.320450] driver_register+0x6c/0xc0 [ 88.320453] ? 0xffffffffc0d67000 [ 88.320457] __hid_register_driver+0x4c/0x80 [ 88.320464] do_one_initcall+0x46/0x1f4 [ 88.320469] ? _cond_resched+0x15/0x30 [ 88.320474] ? kmem_cache_alloc_trace+0x162/0x220 [ 88.320481] ? do_init_module+0x23/0x230 [ 88.320486] do_init_module+0x5c/0x230 [ 88.320491] load_module+0x26e1/0x2990 [ 88.320502] ? ima_post_read_file+0xf0/0x100 [ 88.320508] ? __do_sys_finit_module+0xaa/0x110 [ 88.320512] __do_sys_finit_module+0xaa/0x110 [ 88.320520] do_syscall_64+0x5b/0x180 [ 88.320525] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 88.320528] RIP: 0033:0x7f8d8d1f01fd [ 88.320532] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 5b 8c 0c 00 f7 d8 64 89 01 48 [ 88.320535] RSP: 002b:00007ffefa3bb068 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 88.320539] RAX: ffffffffffffffda RBX: 000055922040cb40 RCX: 00007f8d8d1f01fd [ 88.320541] RDX: 0000000000000000 RSI: 00007f8d8ce4984d RDI: 0000000000000006 [ 88.320543] RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000007 [ 88.320545] R10: 0000000000000006 R11: 0000000000000246 R12: 00007f8d8ce4984d [ 88.320547] R13: 0000000000000000 R14: 000055922040efc0 R15: 000055922040cb40 [ 88.320551] Modules linked in: hid_logitech_hidpp(+) fuse rfcomm ccm xt_CHECKSUM xt_MASQUERADE bridge stp llc nf_nat_tftp nf_conntrack_tftp nf_conntrack_netbios_ns nf_conntrack_broadcast xt_CT ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat tun iptable_mangle iptable_raw iptable_security nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c ip_set nfnetlink ebtable_filter ebtables ip6table_filter ip6_tables cmac bnep sunrpc dm_crypt nls_utf8 hfsplus intel_rapl_msr intel_rapl_common ath9k_htc ath9k_common x86_pkg_temp_thermal intel_powerclamp b43 ath9k_hw coretemp snd_hda_codec_hdmi cordic kvm_intel snd_hda_codec_cirrus mac80211 snd_hda_codec_generic ledtrig_audio kvm snd_hda_intel snd_intel_nhlt irqbypass snd_hda_codec btusb btrtl snd_hda_core ath btbcm ssb snd_hwdep btintel snd_seq crct10dif_pclmul iTCO_wdt snd_seq_device crc32_pclmul bluetooth mmc_core iTCO_vendor_support joydev cfg80211 [ 88.320602] applesmc ghash_clmulni_intel ecdh_generic snd_pcm input_polldev intel_cstate ecc intel_uncore thunderbolt snd_timer i2c_i801 libarc4 rfkill intel_rapl_perf lpc_ich mei_me pcspkr bcm5974 snd bcma mei soundcore acpi_als sbs kfifo_buf sbshc industrialio apple_bl i915 i2c_algo_bit drm_kms_helper drm uas crc32c_intel usb_storage video hid_apple [ 88.320630] CR2: 0000000000000018 [ 88.320633] ---[ end trace 933491c8a4fadeb7 ]--- [ 88.320642] RIP: 0010:hidpp_probe+0x61f/0x948 [hid_logitech_hidpp] [ 88.320645] Code: 81 00 00 48 89 ef e8 f0 d6 ff ff 41 89 c6 85 c0 75 b5 0f b6 44 24 28 48 8b 5d 00 88 44 24 1e 89 44 24 0c 48 8b 83 18 1c 00 00 <48> 8b 48 18 48 8b 83 10 19 00 00 48 8b 40 40 48 89 0c 24 0f b7 80 [ 88.320647] RSP: 0018:ffffb0a6824aba68 EFLAGS: 00010246 [ 88.320650] RAX: 0000000000000000 RBX: ffff93a50756e000 RCX: 0000000000010408 [ 88.320652] RDX: 0000000000000000 RSI: ffff93a51f0ad0a0 RDI: 000000000002d0a0 [ 88.320655] RBP: ffff93a50416da28 R08: ffff93a50416da70 R09: ffff93a50416da70 [ 88.320657] R10: 000000148ae9e60c R11: 00000000000f1525 R12: ffff93a50756e000 [ 88.320659] R13: ffff93a50756f8d0 R14: 0000000000000000 R15: ffff93a50756fc38 [ 88.320662] FS: 00007f8d8c1e0940(0000) GS:ffff93a51f080000(0000) knlGS:0000000000000000 [ 88.320664] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 88.320667] CR2: 0000000000000018 CR3: 00000003996d8003 CR4: 00000000001606e0 To solve this issue: 1. Split g920_get_config() such that all of the device specific communication remains a part of the function and input subsystem initialization bits go to hidpp_ff_init() 2. Move call to hidpp_ff_init() from being a part of g920_get_config() to be the last step of .probe(), right after a call to hid_hw_start() with connect_mask containing HID_CONNECT_HIDINPUT. Fixes: 91cf9a9 ("HID: logitech-hidpp: make .probe usbhid capable") Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> Tested-by: Sam Bazley <sambazley@fastmail.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com> Cc: Henrik Rydberg <rydberg@bitmath.org> Cc: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com> Cc: Austin Palmer <austinp@valvesoftware.com> Cc: linux-input@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org # 5.2+ Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 159d2c7 upstream. qdisc_root() use from netem_enqueue() triggers a lockdep warning. __dev_queue_xmit() uses rcu_read_lock_bh() which is not equivalent to rcu_read_lock() + local_bh_disable_bh as far as lockdep is concerned. WARNING: suspicious RCU usage 5.3.0-rc7+ #0 Not tainted ----------------------------- include/net/sch_generic.h:492 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by syz-executor427/8855: #0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline] #0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x2dc/0x2570 net/ipv4/ip_output.c:214 #1: 00000000b5525c01 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x20a/0x3650 net/core/dev.c:3804 #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: spin_lock include/linux/spinlock.h:338 [inline] #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_xmit_skb net/core/dev.c:3502 [inline] #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_queue_xmit+0x14b8/0x3650 net/core/dev.c:3838 stack backtrace: CPU: 0 PID: 8855 Comm: syz-executor427 Not tainted 5.3.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5357 qdisc_root include/net/sch_generic.h:492 [inline] netem_enqueue+0x1cfb/0x2d80 net/sched/sch_netem.c:479 __dev_xmit_skb net/core/dev.c:3527 [inline] __dev_queue_xmit+0x15d2/0x3650 net/core/dev.c:3838 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip_finish_output2+0x1726/0x2570 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x5fc/0xb90 net/ipv4/ip_output.c:290 ip_finish_output+0x38/0x1f0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_mc_output+0x292/0xf40 net/ipv4/ip_output.c:417 dst_output include/net/dst.h:436 [inline] ip_local_out+0xbb/0x190 net/ipv4/ip_output.c:125 ip_send_skb+0x42/0xf0 net/ipv4/ip_output.c:1555 udp_send_skb.isra.0+0x6b2/0x1160 net/ipv4/udp.c:887 udp_sendmsg+0x1e96/0x2820 net/ipv4/udp.c:1174 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2311 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413 __do_sys_sendmmsg net/socket.c:2442 [inline] __se_sys_sendmmsg net/socket.c:2439 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2439 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit b66f31e ] This patch fixes the lock inversion complaint: ============================================ WARNING: possible recursive locking detected 5.3.0-rc7-dbg+ #1 Not tainted -------------------------------------------- kworker/u16:6/171 is trying to acquire lock: 00000000035c6e6c (&id_priv->handler_mutex){+.+.}, at: rdma_destroy_id+0x78/0x4a0 [rdma_cm] but task is already holding lock: 00000000bc7c307d (&id_priv->handler_mutex){+.+.}, at: iw_conn_req_handler+0x151/0x680 [rdma_cm] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&id_priv->handler_mutex); lock(&id_priv->handler_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kworker/u16:6/171: #0: 00000000e2eaa773 ((wq_completion)iw_cm_wq){+.+.}, at: process_one_work+0x472/0xac0 #1: 000000001efd357b ((work_completion)(&work->work)#3){+.+.}, at: process_one_work+0x476/0xac0 #2: 00000000bc7c307d (&id_priv->handler_mutex){+.+.}, at: iw_conn_req_handler+0x151/0x680 [rdma_cm] stack backtrace: CPU: 3 PID: 171 Comm: kworker/u16:6 Not tainted 5.3.0-rc7-dbg+ #1 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: iw_cm_wq cm_work_handler [iw_cm] Call Trace: dump_stack+0x8a/0xd6 __lock_acquire.cold+0xe1/0x24d lock_acquire+0x106/0x240 __mutex_lock+0x12e/0xcb0 mutex_lock_nested+0x1f/0x30 rdma_destroy_id+0x78/0x4a0 [rdma_cm] iw_conn_req_handler+0x5c9/0x680 [rdma_cm] cm_work_handler+0xe62/0x1100 [iw_cm] process_one_work+0x56d/0xac0 worker_thread+0x7a/0x5d0 kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 This is not a bug as there are actually two lock classes here. Link: https://lore.kernel.org/r/20190930231707.48259-3-bvanassche@acm.org Fixes: de910bd ("RDMA/cma: Simplify locking needed for serialization of callbacks") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 159d2c7 upstream. qdisc_root() use from netem_enqueue() triggers a lockdep warning. __dev_queue_xmit() uses rcu_read_lock_bh() which is not equivalent to rcu_read_lock() + local_bh_disable_bh as far as lockdep is concerned. WARNING: suspicious RCU usage 5.3.0-rc7+ #0 Not tainted ----------------------------- include/net/sch_generic.h:492 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by syz-executor427/8855: #0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline] #0: 00000000b5525c01 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x2dc/0x2570 net/ipv4/ip_output.c:214 #1: 00000000b5525c01 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x20a/0x3650 net/core/dev.c:3804 #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: spin_lock include/linux/spinlock.h:338 [inline] #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_xmit_skb net/core/dev.c:3502 [inline] #2: 00000000364bae92 (&(&sch->q.lock)->rlock){+.-.}, at: __dev_queue_xmit+0x14b8/0x3650 net/core/dev.c:3838 stack backtrace: CPU: 0 PID: 8855 Comm: syz-executor427 Not tainted 5.3.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5357 qdisc_root include/net/sch_generic.h:492 [inline] netem_enqueue+0x1cfb/0x2d80 net/sched/sch_netem.c:479 __dev_xmit_skb net/core/dev.c:3527 [inline] __dev_queue_xmit+0x15d2/0x3650 net/core/dev.c:3838 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip_finish_output2+0x1726/0x2570 net/ipv4/ip_output.c:228 __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x5fc/0xb90 net/ipv4/ip_output.c:290 ip_finish_output+0x38/0x1f0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_mc_output+0x292/0xf40 net/ipv4/ip_output.c:417 dst_output include/net/dst.h:436 [inline] ip_local_out+0xbb/0x190 net/ipv4/ip_output.c:125 ip_send_skb+0x42/0xf0 net/ipv4/ip_output.c:1555 udp_send_skb.isra.0+0x6b2/0x1160 net/ipv4/udp.c:887 udp_sendmsg+0x1e96/0x2820 net/ipv4/udp.c:1174 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x3e2/0x920 net/socket.c:2311 __sys_sendmmsg+0x1bf/0x4d0 net/socket.c:2413 __do_sys_sendmmsg net/socket.c:2442 [inline] __se_sys_sendmmsg net/socket.c:2439 [inline] __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2439 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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While v2.6.26 commit b75db73 ("[SCSI] zfcp: Add qtcb dump to hba debug trace") is right that we don't want to flood the (payload) trace ring buffer, we don't trace successful FCP command responses by default. So we can include the channel log for problem determination with failed responses of any FSF request type. Fixes: b75db73 ("[SCSI] zfcp: Add qtcb dump to hba debug trace") Fixes: a54ca0f ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.") Cc: <stable@vger.kernel.org> #2.6.38+ Link: https://lore.kernel.org/r/e37597b5c4ae123aaa85fd86c23a9f71e994e4a9.1572018132.git.bblock@linux.ibm.com Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Steffen Maier <maier@linux.ibm.com> Signed-off-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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Fix the following lockdep warning: ============================================ WARNING: possible recursive locking detected 5.4.0-rc6-dbg+ #2 Not tainted -------------------------------------------- systemd-udevd/130 is trying to acquire lock: ffffffff826b05d0 (cpu_hotplug_lock.rw_sem){++++}, at: irq_calc_affinity_vectors+0x63/0x90 but task is already holding lock: ffffffff826b05d0 (cpu_hotplug_lock.rw_sem){++++}, at: lpfc_sli4_enable_intr+0x422/0xd50 [lpfc] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(cpu_hotplug_lock.rw_sem); lock(cpu_hotplug_lock.rw_sem); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by systemd-udevd/130: #0: ffff8880d53fe210 (&dev->mutex){....}, at: __device_driver_lock+0x4a/0x70 #1: ffffffff826b05d0 (cpu_hotplug_lock.rw_sem){++++}, at: lpfc_sli4_enable_intr+0x422/0xd50 [lpfc] stack backtrace: CPU: 1 PID: 130 Comm: systemd-udevd Not tainted 5.4.0-rc6-dbg+ #2 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: dump_stack+0xa5/0xe6 __lock_acquire.cold+0xf7/0x23a lock_acquire+0x106/0x240 cpus_read_lock+0x41/0xe0 irq_calc_affinity_vectors+0x63/0x90 __pci_enable_msix_range+0x10a/0x950 pci_alloc_irq_vectors_affinity+0x144/0x210 lpfc_sli4_enable_intr+0x4b2/0xd50 [lpfc] lpfc_pci_probe_one+0x1411/0x22b0 [lpfc] local_pci_probe+0x7c/0xc0 pci_device_probe+0x25d/0x390 really_probe+0x170/0x510 driver_probe_device+0x127/0x190 device_driver_attach+0x98/0xa0 __driver_attach+0xb6/0x1a0 bus_for_each_dev+0x100/0x150 driver_attach+0x31/0x40 bus_add_driver+0x246/0x300 driver_register+0xe0/0x170 __pci_register_driver+0xde/0xf0 lpfc_init+0x134/0x1000 [lpfc] do_one_initcall+0xda/0x47e do_init_module+0x10a/0x3b0 load_module+0x4318/0x47c0 __do_sys_finit_module+0x134/0x1d0 __x64_sys_finit_module+0x47/0x50 do_syscall_64+0x6f/0x2e0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: dcaa213 ("scsi: lpfc: Change default IRQ model on AMD architectures") Link: https://lore.kernel.org/r/20191107052158.25788-4-bvanassche@acm.org Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: James Smart <jsmart2021@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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In function __ufshcd_query_descriptor(), in the event of an error happening, we directly goto out_unlock and forget to invaliate hba->dev_cmd.query.descriptor pointer. This results in this pointer still valid in ufshcd_copy_query_response() for other query requests which go through ufshcd_exec_raw_upiu_cmd(). This will cause __memcpy() crash and system hangs. Log as shown below: Unable to handle kernel paging request at virtual address ffff000012233c40 Mem abort info: ESR = 0x96000047 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000047 CM = 0, WnR = 1 swapper pgtable: 4k pages, 48-bit VAs, pgdp = 0000000028cc735c [ffff000012233c40] pgd=00000000bffff003, pud=00000000bfffe003, pmd=00000000ba8b8003, pte=0000000000000000 Internal error: Oops: 96000047 [#2] PREEMPT SMP ... Call trace: __memcpy+0x74/0x180 ufshcd_issue_devman_upiu_cmd+0x250/0x3c0 ufshcd_exec_raw_upiu_cmd+0xfc/0x1a8 ufs_bsg_request+0x178/0x3b0 bsg_queue_rq+0xc0/0x118 blk_mq_dispatch_rq_list+0xb0/0x538 blk_mq_sched_dispatch_requests+0x18c/0x1d8 __blk_mq_run_hw_queue+0xb4/0x118 blk_mq_run_work_fn+0x28/0x38 process_one_work+0x1ec/0x470 worker_thread+0x48/0x458 kthread+0x130/0x138 ret_from_fork+0x10/0x1c Code: 540000ab a8c12027 a88120c7 a8c12027 (a88120c7) ---[ end trace 793e1eb5dff69f2d ]--- note: kworker/0:2H[2054] exited with preempt_count 1 This patch is to move "descriptor = NULL" down to below the label "out_unlock". Fixes: d44a5f9(ufs: query descriptor API) Link: https://lore.kernel.org/r/20191112223436.27449-3-huobean@gmail.com Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Bean Huo <beanhuo@micron.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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[ Upstream commit e74540b ] When the extent tree is modified, it should be protected by inode cluster lock and ip_alloc_sem. The extent tree is accessed and modified in the ocfs2_prepare_inode_for_write, but isn't protected by ip_alloc_sem. The following is a case. The function ocfs2_fiemap is accessing the extent tree, which is modified at the same time. kernel BUG at fs/ocfs2/extent_map.c:475! invalid opcode: 0000 [#1] SMP Modules linked in: tun ocfs2 ocfs2_nodemanager configfs ocfs2_stackglue [...] CPU: 16 PID: 14047 Comm: o2info Not tainted 4.1.12-124.23.1.el6uek.x86_64 #2 Hardware name: Oracle Corporation ORACLE SERVER X7-2L/ASM, MB MECH, X7-2L, BIOS 42040600 10/19/2018 task: ffff88019487e200 ti: ffff88003daa4000 task.ti: ffff88003daa4000 RIP: ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2] Call Trace: ocfs2_fiemap+0x1e3/0x430 [ocfs2] do_vfs_ioctl+0x155/0x510 SyS_ioctl+0x81/0xa0 system_call_fastpath+0x18/0xd8 Code: 18 48 c7 c6 60 7f 65 a0 31 c0 bb e2 ff ff ff 48 8b 4a 40 48 8b 7a 28 48 c7 c2 78 2d 66 a0 e8 38 4f 05 00 e9 28 fe ff ff 0f 1f 00 <0f> 0b 66 0f 1f 44 00 00 bb 86 ff ff ff e9 13 fe ff ff 66 0f 1f RIP ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2] ---[ end trace c8aa0c8180e869dc ]--- Kernel panic - not syncing: Fatal exception Kernel Offset: disabled This issue can be reproduced every week in a production environment. This issue is related to the usage mode. If others use ocfs2 in this mode, the kernel will panic frequently. [akpm@linux-foundation.org: coding style fixes] [Fix new warning due to unused function by removing said function - Linus ] Link: http://lkml.kernel.org/r/1568772175-2906-2-git-send-email-sunny.s.zhang@oracle.com Signed-off-by: Shuning Zhang <sunny.s.zhang@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Gang He <ghe@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 7bd4628 ] There is a possible race between USB suspend and main thread: 1. After processing the command response, main thread will submit rx_cmd URB back so as to process next command response, by calling mwifiex_usb_submit_rx_urb. 2. During USB suspend, the suspend handler will check if rx_cmd URB is pending(submitted) and if true, kill this URB. There is a possible race between #1 and #2, where rx_cmd URB will be submitted by main thread(#1) after the suspend handler check in #2. To fix this, check if device is already suspended in mwifiex_usb_submit_rx_urb, in which case do not submit the URB. Signed-off-by: Vidya Dharmaraju <vidyad@marvell.com> Signed-off-by: Cathy Luo <cluo@marvell.com> Signed-off-by: Ganapathi Bhat <gbhat@marvell.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 867d4aa ] The geni_se_clk_freq_match() has some strange semantics. Specifically it is defined with two modes: 1. It can find a clock that's an exact multiple of the requested rate 2. It can find a non-exact match but it can't handle multiples then ...but callers should always be able to handle a clock that is a multiple of the requested clock so mode #2 doesn't really make sense. Let's change the semantics so that the non-exact match can also accept multiples and then change the code to handle that. The only caller of this code is the unlanded SPI driver [1] which currently passes "exact = True", thus it should be safe to change the semantics in this way. ...and, in fact, the SPI driver should likely be modified to pass "exact = False" (with the new semantics) since that will allow it to work with SPI devices that request a clock rate that doesn't exactly match a rate we can make. [1] https://lkml.kernel.org/r/1535107336-2214-1-git-send-email-dkota@codeaurora.org Fixes: eddac5a ("soc: qcom: Add GENI based QUP Wrapper driver") Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: Andy Gross <andy.gross@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit d3ae96c ] Currently with GLINK_SSR enabled each fatal crash results in servicing a crash from wdog as well. This is due to a race that occurs in setting the running flag in the shutdown path. Fix this by moving the running flag to the end of fatal interrupt handler. Crash Logs: qcom-q6v5-pil 4080000.remoteproc: fatal error without message remoteproc remoteproc0: crash detected in 4080000.remoteproc: type fatal error remoteproc remoteproc0: handling crash #1 in 4080000.remoteproc remoteproc remoteproc0: recovering 4080000.remoteproc qcom-q6v5-pil 4080000.remoteproc: watchdog without message remoteproc remoteproc0: crash detected in 4080000.remoteproc: type watchdog remoteproc:glink-edge: intent request timed out qcom_glink_ssr remoteproc:glink-edge.glink_ssr.-1.-1: failed to send cleanup message qcom_glink_ssr remoteproc:glink-edge.glink_ssr.-1.-1: timeout waiting for cleanup done message qcom-q6v5-pil 4080000.remoteproc: timed out on wait qcom-q6v5-pil 4080000.remoteproc: port failed halt remoteproc remoteproc0: stopped remote processor 4080000.remoteproc qcom-q6v5-pil 4080000.remoteproc: MBA booted, loading mpss remoteproc remoteproc0: remote processor 4080000.remoteproc is now up remoteproc remoteproc0: handling crash #2 in 4080000.remoteproc remoteproc remoteproc0: recovering 4080000.remoteproc qcom-q6v5-pil 4080000.remoteproc: port failed halt remoteproc remoteproc0: stopped remote processor 4080000.remoteproc qcom-q6v5-pil 4080000.remoteproc: MBA booted, loading mpss remoteproc remoteproc0: remote processor 4080000.remoteproc is now up Suggested-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Sibi Sankar <sibis@codeaurora.org> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 6408136 ] We've recently seen a workload on XFS filesystems with a repeatable deadlock between background writeback and a multi-process application doing concurrent writes and fsyncs to a small range of a file. range_cyclic writeback Process 1 Process 2 xfs_vm_writepages write_cache_pages writeback_index = 2 cycled = 0 .... find page 2 dirty lock Page 2 ->writepage page 2 writeback page 2 clean page 2 added to bio no more pages write() locks page 1 dirties page 1 locks page 2 dirties page 1 fsync() .... xfs_vm_writepages write_cache_pages start index 0 find page 1 towrite lock Page 1 ->writepage page 1 writeback page 1 clean page 1 added to bio find page 2 towrite lock Page 2 page 2 is writeback <blocks> write() locks page 1 dirties page 1 fsync() .... xfs_vm_writepages write_cache_pages start index 0 !done && !cycled sets index to 0, restarts lookup find page 1 dirty find page 1 towrite lock Page 1 page 1 is writeback <blocks> lock Page 1 <blocks> DEADLOCK because: - process 1 needs page 2 writeback to complete to make enough progress to issue IO pending for page 1 - writeback needs page 1 writeback to complete so process 2 can progress and unlock the page it is blocked on, then it can issue the IO pending for page 2 - process 2 can't make progress until process 1 issues IO for page 1 The underlying cause of the problem here is that range_cyclic writeback is processing pages in descending index order as we hold higher index pages in a structure controlled from above write_cache_pages(). The write_cache_pages() caller needs to be able to submit these pages for IO before write_cache_pages restarts writeback at mapping index 0 to avoid wcp inverting the page lock/writeback wait order. generic_writepages() is not susceptible to this bug as it has no private context held across write_cache_pages() - filesystems using this infrastructure always submit pages in ->writepage immediately and so there is no problem with range_cyclic going back to mapping index 0. However: mpage_writepages() has a private bio context, exofs_writepages() has page_collect fuse_writepages() has fuse_fill_wb_data nfs_writepages() has nfs_pageio_descriptor xfs_vm_writepages() has xfs_writepage_ctx All of these ->writepages implementations can hold pages under writeback in their private structures until write_cache_pages() returns, and hence they are all susceptible to this deadlock. Also worth noting is that ext4 has it's own bastardised version of write_cache_pages() and so it /may/ have an equivalent deadlock. I looked at the code long enough to understand that it has a similar retry loop for range_cyclic writeback reaching the end of the file and then promptly ran away before my eyes bled too much. I'll leave it for the ext4 developers to determine if their code is actually has this deadlock and how to fix it if it has. There's a few ways I can see avoid this deadlock. There's probably more, but these are the first I've though of: 1. get rid of range_cyclic altogether 2. range_cyclic always stops at EOF, and we start again from writeback index 0 on the next call into write_cache_pages() 2a. wcp also returns EAGAIN to ->writepages implementations to indicate range cyclic has hit EOF. writepages implementations can then flush the current context and call wpc again to continue. i.e. lift the retry into the ->writepages implementation 3. range_cyclic uses trylock_page() rather than lock_page(), and it skips pages it can't lock without blocking. It will already do this for pages under writeback, so this seems like a no-brainer 3a. all non-WB_SYNC_ALL writeback uses trylock_page() to avoid blocking as per pages under writeback. I don't think #1 is an option - range_cyclic prevents frequently dirtied lower file offset from starving background writeback of rarely touched higher file offsets. #2 is simple, and I don't think it will have any impact on performance as going back to the start of the file implies an immediate seek. We'll have exactly the same number of seeks if we switch writeback to another inode, and then come back to this one later and restart from index 0. #2a is pretty much "status quo without the deadlock". Moving the retry loop up into the wcp caller means we can issue IO on the pending pages before calling wcp again, and so avoid locking or waiting on pages in the wrong order. I'm not convinced we need to do this given that we get the same thing from #2 on the next writeback call from the writeback infrastructure. #3 is really just a band-aid - it doesn't fix the access/wait inversion problem, just prevents it from becoming a deadlock situation. I'd prefer we fix the inversion, not sweep it under the carpet like this. #3a is really an optimisation that just so happens to include the band-aid fix of #3. So it seems that the simplest way to fix this issue is to implement solution #2 Link: http://lkml.kernel.org/r/20181005054526.21507-1-david@fromorbit.com Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Jan Kara <jack@suse.de> Cc: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 089bca2 ] All bonding device has same lockdep key and subclass is initialized with nest_level. But actual nest_level value can be changed when a lower device is attached. And at this moment, the subclass should be updated but it seems to be unsafe. So this patch makes bonding use dynamic lockdep key instead of the subclass. Test commands: ip link add bond0 type bond for i in {1..5} do let A=$i-1 ip link add bond$i type bond ip link set bond$i master bond$A done ip link set bond5 master bond0 Splat looks like: [ 307.992912] WARNING: possible recursive locking detected [ 307.993656] 5.4.0-rc3+ #96 Tainted: G W [ 307.994367] -------------------------------------------- [ 307.995092] ip/761 is trying to acquire lock: [ 307.995710] ffff8880513aac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding] [ 307.997045] but task is already holding lock: [ 307.997923] ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding] [ 307.999215] other info that might help us debug this: [ 308.000251] Possible unsafe locking scenario: [ 308.001137] CPU0 [ 308.001533] ---- [ 308.001915] lock(&(&bond->stats_lock)->rlock#2/2); [ 308.002609] lock(&(&bond->stats_lock)->rlock#2/2); [ 308.003302] *** DEADLOCK *** [ 308.004310] May be due to missing lock nesting notation [ 308.005319] 3 locks held by ip/761: [ 308.005830] #0: ffffffff9fcc42b0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0 [ 308.006894] #1: ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding] [ 308.008243] #2: ffffffff9f9219c0 (rcu_read_lock){....}, at: bond_get_stats+0x9f/0x500 [bonding] [ 308.009422] stack backtrace: [ 308.010124] CPU: 0 PID: 761 Comm: ip Tainted: G W 5.4.0-rc3+ #96 [ 308.011097] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 308.012179] Call Trace: [ 308.012601] dump_stack+0x7c/0xbb [ 308.013089] __lock_acquire+0x269d/0x3de0 [ 308.013669] ? register_lock_class+0x14d0/0x14d0 [ 308.014318] lock_acquire+0x164/0x3b0 [ 308.014858] ? bond_get_stats+0xb8/0x500 [bonding] [ 308.015520] _raw_spin_lock_nested+0x2e/0x60 [ 308.016129] ? bond_get_stats+0xb8/0x500 [bonding] [ 308.017215] bond_get_stats+0xb8/0x500 [bonding] [ 308.018454] ? bond_arp_rcv+0xf10/0xf10 [bonding] [ 308.019710] ? rcu_read_lock_held+0x90/0xa0 [ 308.020605] ? rcu_read_lock_sched_held+0xc0/0xc0 [ 308.021286] ? bond_get_stats+0x9f/0x500 [bonding] [ 308.021953] dev_get_stats+0x1ec/0x270 [ 308.022508] bond_get_stats+0x1d1/0x500 [bonding] Fixes: d3fff6c ("net: add netdev_lockdep_set_classes() helper") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit e74540b ] When the extent tree is modified, it should be protected by inode cluster lock and ip_alloc_sem. The extent tree is accessed and modified in the ocfs2_prepare_inode_for_write, but isn't protected by ip_alloc_sem. The following is a case. The function ocfs2_fiemap is accessing the extent tree, which is modified at the same time. kernel BUG at fs/ocfs2/extent_map.c:475! invalid opcode: 0000 [#1] SMP Modules linked in: tun ocfs2 ocfs2_nodemanager configfs ocfs2_stackglue [...] CPU: 16 PID: 14047 Comm: o2info Not tainted 4.1.12-124.23.1.el6uek.x86_64 #2 Hardware name: Oracle Corporation ORACLE SERVER X7-2L/ASM, MB MECH, X7-2L, BIOS 42040600 10/19/2018 task: ffff88019487e200 ti: ffff88003daa4000 task.ti: ffff88003daa4000 RIP: ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2] Call Trace: ocfs2_fiemap+0x1e3/0x430 [ocfs2] do_vfs_ioctl+0x155/0x510 SyS_ioctl+0x81/0xa0 system_call_fastpath+0x18/0xd8 Code: 18 48 c7 c6 60 7f 65 a0 31 c0 bb e2 ff ff ff 48 8b 4a 40 48 8b 7a 28 48 c7 c2 78 2d 66 a0 e8 38 4f 05 00 e9 28 fe ff ff 0f 1f 00 <0f> 0b 66 0f 1f 44 00 00 bb 86 ff ff ff e9 13 fe ff ff 66 0f 1f RIP ocfs2_get_clusters_nocache.isra.11+0x390/0x550 [ocfs2] ---[ end trace c8aa0c8180e869dc ]--- Kernel panic - not syncing: Fatal exception Kernel Offset: disabled This issue can be reproduced every week in a production environment. This issue is related to the usage mode. If others use ocfs2 in this mode, the kernel will panic frequently. [akpm@linux-foundation.org: coding style fixes] [Fix new warning due to unused function by removing said function - Linus ] Link: http://lkml.kernel.org/r/1568772175-2906-2-git-send-email-sunny.s.zhang@oracle.com Signed-off-by: Shuning Zhang <sunny.s.zhang@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Gang He <ghe@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 6f67097 ] When lockdep is enabled, plugging Thunderbolt dock on Dominik's laptop triggers following splat: ====================================================== WARNING: possible circular locking dependency detected 5.3.0-rc6+ #1 Tainted: G T ------------------------------------------------------ pool-/usr/lib/b/1258 is trying to acquire lock: 000000005ab0ad43 (pci_rescan_remove_lock){+.+.}, at: authorized_store+0xe8/0x210 but task is already holding lock: 00000000bfb796b5 (&tb->lock){+.+.}, at: authorized_store+0x7c/0x210 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&tb->lock){+.+.}: __mutex_lock+0xac/0x9a0 tb_domain_add+0x2d/0x130 nhi_probe+0x1dd/0x330 pci_device_probe+0xd2/0x150 really_probe+0xee/0x280 driver_probe_device+0x50/0xc0 bus_for_each_drv+0x84/0xd0 __device_attach+0xe4/0x150 pci_bus_add_device+0x4e/0x70 pci_bus_add_devices+0x2e/0x66 pci_bus_add_devices+0x59/0x66 pci_bus_add_devices+0x59/0x66 enable_slot+0x344/0x450 acpiphp_check_bridge.part.0+0x119/0x150 acpiphp_hotplug_notify+0xaa/0x140 acpi_device_hotplug+0xa2/0x3f0 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x234/0x580 worker_thread+0x50/0x3b0 kthread+0x10a/0x140 ret_from_fork+0x3a/0x50 -> #0 (pci_rescan_remove_lock){+.+.}: __lock_acquire+0xe54/0x1ac0 lock_acquire+0xb8/0x1b0 __mutex_lock+0xac/0x9a0 authorized_store+0xe8/0x210 kernfs_fop_write+0x125/0x1b0 vfs_write+0xc2/0x1d0 ksys_write+0x6c/0xf0 do_syscall_64+0x50/0x180 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&tb->lock); lock(pci_rescan_remove_lock); lock(&tb->lock); lock(pci_rescan_remove_lock); *** DEADLOCK *** 5 locks held by pool-/usr/lib/b/1258: #0: 000000003df1a1ad (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x4d/0x60 #1: 0000000095a40b02 (sb_writers#6){.+.+}, at: vfs_write+0x185/0x1d0 #2: 0000000017a7d714 (&of->mutex){+.+.}, at: kernfs_fop_write+0xf2/0x1b0 #3: 000000004f262981 (kn->count#208){.+.+}, at: kernfs_fop_write+0xfa/0x1b0 #4: 00000000bfb796b5 (&tb->lock){+.+.}, at: authorized_store+0x7c/0x210 stack backtrace: CPU: 0 PID: 1258 Comm: pool-/usr/lib/b Tainted: G T 5.3.0-rc6+ #1 On an system using ACPI hotplug the host router gets hotplugged first and then the firmware starts sending notifications about connected devices so the above scenario should not happen in reality. However, after taking a second look at commit a03e828 ("thunderbolt: Serialize PCIe tunnel creation with PCI rescan") that introduced the locking, I don't think it is actually correct. It may have cured the symptom but probably the real root cause was somewhere closer to PCI stack and possibly is already fixed with recent kernels. I also tried to reproduce the original issue with the commit reverted but could not. So to keep lockdep happy and the code bit less complex drop calls to pci_lock_rescan_remove()/pci_unlock_rescan_remove() in tb_switch_set_authorized() effectively reverting a03e828. Link: https://lkml.org/lkml/2019/8/30/513 Fixes: a03e828 ("thunderbolt: Serialize PCIe tunnel creation with PCI rescan") Reported-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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As virtual_context_destroy() may be called from a request signal, it may be called from inside an irq-off section, and so we need to do a full save/restore of the irq state rather than blindly re-enable irqs upon unlocking. <4> [110.024262] WARNING: inconsistent lock state <4> [110.024277] 5.4.0-rc8-CI-CI_DRM_7489+ #1 Tainted: G U <4> [110.024292] -------------------------------- <4> [110.024305] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. <4> [110.024323] kworker/0:0/5 [HC0[0]:SC0[0]:HE1:SE1] takes: <4> [110.024338] ffff88826a0c7a18 (&(&rq->lock)->rlock){?.-.}, at: i915_request_retire+0x221/0x930 [i915] <4> [110.024592] {IN-HARDIRQ-W} state was registered at: <4> [110.024612] lock_acquire+0xa7/0x1c0 <4> [110.024627] _raw_spin_lock_irqsave+0x33/0x50 <4> [110.024788] intel_engine_breadcrumbs_irq+0x38c/0x600 [i915] <4> [110.024808] irq_work_run_list+0x49/0x70 <4> [110.024824] irq_work_run+0x26/0x50 <4> [110.024839] smp_irq_work_interrupt+0x44/0x1e0 <4> [110.024855] irq_work_interrupt+0xf/0x20 <4> [110.024871] __do_softirq+0xb7/0x47f <4> [110.024885] irq_exit+0xba/0xc0 <4> [110.024898] do_IRQ+0x83/0x160 <4> [110.024910] ret_from_intr+0x0/0x1d <4> [110.024922] irq event stamp: 172864 <4> [110.024938] hardirqs last enabled at (172863): [<ffffffff819ea214>] _raw_spin_unlock_irq+0x24/0x50 <4> [110.024963] hardirqs last disabled at (172864): [<ffffffff819e9fba>] _raw_spin_lock_irq+0xa/0x40 <4> [110.024988] softirqs last enabled at (172812): [<ffffffff81c00385>] __do_softirq+0x385/0x47f <4> [110.025012] softirqs last disabled at (172797): [<ffffffff810b829a>] irq_exit+0xba/0xc0 <4> [110.025031] other info that might help us debug this: <4> [110.025049] Possible unsafe locking scenario: <4> [110.025065] CPU0 <4> [110.025075] ---- <4> [110.025084] lock(&(&rq->lock)->rlock); <4> [110.025099] <Interrupt> <4> [110.025109] lock(&(&rq->lock)->rlock); <4> [110.025124] *** DEADLOCK *** <4> [110.025144] 4 locks held by kworker/0:0/5: <4> [110.025156] #0: ffff88827588f528 ((wq_completion)events){+.+.}, at: process_one_work+0x1de/0x620 <4> [110.025187] #1: ffffc9000006fe78 ((work_completion)(&engine->retire_work)){+.+.}, at: process_one_work+0x1de/0x620 <4> [110.025219] #2: ffff88825605e270 (&kernel#2){+.+.}, at: engine_retire+0x57/0xe0 [i915] <4> [110.025405] #3: ffff88826a0c7a18 (&(&rq->lock)->rlock){?.-.}, at: i915_request_retire+0x221/0x930 [i915] <4> [110.025634] stack backtrace: <4> [110.025653] CPU: 0 PID: 5 Comm: kworker/0:0 Tainted: G U 5.4.0-rc8-CI-CI_DRM_7489+ #1 <4> [110.025675] Hardware name: /NUC7i5BNB, BIOS BNKBL357.86A.0054.2017.1025.1822 10/25/2017 <4> [110.025856] Workqueue: events engine_retire [i915] <4> [110.025872] Call Trace: <4> [110.025891] dump_stack+0x71/0x9b <4> [110.025907] mark_lock+0x49a/0x500 <4> [110.025926] ? print_shortest_lock_dependencies+0x200/0x200 <4> [110.025946] mark_held_locks+0x49/0x70 <4> [110.025962] ? _raw_spin_unlock_irq+0x24/0x50 <4> [110.025978] lockdep_hardirqs_on+0xa2/0x1c0 <4> [110.025995] _raw_spin_unlock_irq+0x24/0x50 <4> [110.026171] virtual_context_destroy+0xc5/0x2e0 [i915] <4> [110.026376] __active_retire+0xb4/0x290 [i915] <4> [110.026396] dma_fence_signal_locked+0x9e/0x1b0 <4> [110.026613] i915_request_retire+0x451/0x930 [i915] <4> [110.026766] retire_requests+0x4d/0x60 [i915] <4> [110.026919] engine_retire+0x63/0xe0 [i915] Fixes: b1e3177 ("drm/i915: Coordinate i915_active with its own mutex") Fixes: 6d06779 ("drm/i915: Load balancing across a virtual engine") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191205145934.663183-1-chris@chris-wilson.co.uk (cherry picked from commit 6f7ac82) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
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Target creation triggers a new BUG_ON introduced in in commit 4d43d39 ("workqueue: Try to catch flush_work() without INIT_WORK()."). The BUG_ON reveals an attempt to flush free_work in qla24xx_do_nack_work before it's initialized in qlt_unreg_sess: WARNING: CPU: 7 PID: 211 at kernel/workqueue.c:3031 __flush_work.isra.38+0x40/0x2e0 CPU: 7 PID: 211 Comm: kworker/7:1 Kdump: loaded Tainted: G E 5.3.0-rc7-vanilla+ #2 Workqueue: qla2xxx_wq qla2x00_iocb_work_fn [qla2xxx] NIP: c000000000159620 LR: c0080000009d91b0 CTR: c0000000001598c0 REGS: c000000005f3f730 TRAP: 0700 Tainted: G E (5.3.0-rc7-vanilla+) MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002222 XER: 00000000 CFAR: c0000000001598d0 IRQMASK: 0 GPR00: c0080000009d91b0 c000000005f3f9c0 c000000001670a00 c0000003f8655ca8 GPR04: c0000003f8655c00 000000000000ffff 0000000000000011 ffffffffffffffff GPR08: c008000000949228 0000000000000000 0000000000000001 c0080000009e7780 GPR12: 0000000000002200 c00000003fff6200 c000000000161bc8 0000000000000004 GPR16: c0000003f9d68280 0000000002000000 0000000000000005 0000000000000003 GPR20: 0000000000000002 000000000000ffff 0000000000000000 fffffffffffffef7 GPR24: c000000004f73848 c000000004f73838 c000000004f73f28 c000000005f3fb60 GPR28: c000000004f73e48 c000000004f73c80 c000000004f73818 c0000003f9d68280 NIP [c000000000159620] __flush_work.isra.38+0x40/0x2e0 LR [c0080000009d91b0] qla24xx_do_nack_work+0x88/0x180 [qla2xxx] Call Trace: [c000000005f3f9c0] [c000000000159644] __flush_work.isra.38+0x64/0x2e0 (unreliable) [c000000005f3fa50] [c0080000009d91a0] qla24xx_do_nack_work+0x78/0x180 [qla2xxx] [c000000005f3fae0] [c0080000009496ec] qla2x00_do_work+0x604/0xb90 [qla2xxx] [c000000005f3fc40] [c008000000949cd8] qla2x00_iocb_work_fn+0x60/0xe0 [qla2xxx] [c000000005f3fc80] [c000000000157bb8] process_one_work+0x2c8/0x5b0 [c000000005f3fd10] [c000000000157f28] worker_thread+0x88/0x660 [c000000005f3fdb0] [c000000000161d64] kthread+0x1a4/0x1b0 [c000000005f3fe20] [c00000000000b960] ret_from_kernel_thread+0x5c/0x7c Instruction dump: 3d22001d 892966b1 7d908026 91810008 f821ff71 69290001 0b090000 2e290000 40920200 e9230018 7d2a0074 794ad182 <0b0a0000> 2fa90000 419e01e8 7c0802a6 ---[ end trace 5ccf335d4f90fcb8 ]--- Fixes: 1021f0b ("scsi: qla2xxx: allow session delete to finish before create.") Cc: Quinn Tran <qutran@marvell.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20191125165702.1013-4-r.bolshakov@yadro.com Acked-by: Himanshu Madhani <hmadhani@marvell.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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Each AFS mountpoint has strings that define the target to be mounted. This is required to end in a dot that is supposed to be stripped off. The string can include suffixes of ".readonly" or ".backup" - which are supposed to come before the terminal dot. To add to the confusion, the "fs lsmount" afs utility does not show the terminal dot when displaying the string. The kernel mount source string parser, however, assumes that the terminal dot marks the suffix and that the suffix is always "" and is thus ignored. In most cases, there is no suffix and this is not a problem - but if there is a suffix, it is lost and this affects the ability to mount the correct volume. The command line mount command, on the other hand, is expected not to include a terminal dot - so the problem doesn't arise there. Fix this by making sure that the dot exists and then stripping it when passing the string to the mount configuration. Fixes: bec5eb6 ("AFS: Implement an autocell mount capability [ver #2]") Reported-by: Jonathan Billings <jsbillings@jsbillings.org> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
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When commit: 69c1f39 ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") moved the x86 specific EFI earlyprintk implementation to a shared location, it also tweaked the behaviour. In particular, it dropped a trick with full framebuffer remapping after page initialization, leading to two regressions: 1) very slow scrolling after page initialization, 2) kernel hang when the 'keep_bootcon' command line argument is passed. Putting the tweak back fixes #2 and mitigates #1, i.e., it limits the slow behavior to the early boot stages, presumably due to eliminating heavy map()/unmap() operations per each pixel line on the screen. [ ardb: ensure efifb is unmapped again unless keep_bootcon is in effect. ] [ mingo: speling fixes. ] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: linux-efi@vger.kernel.org Fixes: 69c1f39 ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") Link: https://lkml.kernel.org/r/20191206165542.31469-7-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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No error code was being set on this error path. Cc: stable@vger.kernel.org Fixes: ad4b1eb ("KEYS: asym_tpm: Implement encryption operation [ver #2]") Fixes: c08fed7 ("KEYS: Implement encrypt, decrypt and sign for software asymmetric key [ver #2]") Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
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We got another syzbot report [1] that tells us we must use
write_lock_irq()/write_unlock_irq() to avoid possible deadlock.
[1]
WARNING: inconsistent lock state
5.5.0-rc1-syzkaller #0 Not tainted
--------------------------------
inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-R} usage.
syz-executor826/9605 [HC1[1]:SC0[0]:HE0:SE1] takes:
ffffffff8a128718 (disc_data_lock){+-..}, at: sp_get.isra.0+0x1d/0xf0 drivers/net/ppp/ppp_synctty.c:138
{HARDIRQ-ON-W} state was registered at:
lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485
__raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline]
_raw_write_lock_bh+0x33/0x50 kernel/locking/spinlock.c:319
sixpack_close+0x1d/0x250 drivers/net/hamradio/6pack.c:657
tty_ldisc_close.isra.0+0x119/0x1a0 drivers/tty/tty_ldisc.c:489
tty_set_ldisc+0x230/0x6b0 drivers/tty/tty_ldisc.c:585
tiocsetd drivers/tty/tty_io.c:2337 [inline]
tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2597
vfs_ioctl fs/ioctl.c:47 [inline]
file_ioctl fs/ioctl.c:545 [inline]
do_vfs_ioctl+0x977/0x14e0 fs/ioctl.c:732
ksys_ioctl+0xab/0xd0 fs/ioctl.c:749
__do_sys_ioctl fs/ioctl.c:756 [inline]
__se_sys_ioctl fs/ioctl.c:754 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:754
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
irq event stamp: 3946
hardirqs last enabled at (3945): [<ffffffff87c86e43>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline]
hardirqs last enabled at (3945): [<ffffffff87c86e43>] _raw_spin_unlock_irq+0x23/0x80 kernel/locking/spinlock.c:199
hardirqs last disabled at (3946): [<ffffffff8100675f>] trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42
softirqs last enabled at (2658): [<ffffffff86a8b4df>] spin_unlock_bh include/linux/spinlock.h:383 [inline]
softirqs last enabled at (2658): [<ffffffff86a8b4df>] clusterip_netdev_event+0x46f/0x670 net/ipv4/netfilter/ipt_CLUSTERIP.c:222
softirqs last disabled at (2656): [<ffffffff86a8b22b>] spin_lock_bh include/linux/spinlock.h:343 [inline]
softirqs last disabled at (2656): [<ffffffff86a8b22b>] clusterip_netdev_event+0x1bb/0x670 net/ipv4/netfilter/ipt_CLUSTERIP.c:196
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(disc_data_lock);
<Interrupt>
lock(disc_data_lock);
*** DEADLOCK ***
5 locks held by syz-executor826/9605:
#0: ffff8880a905e198 (&tty->legacy_mutex){+.+.}, at: tty_lock+0xc7/0x130 drivers/tty/tty_mutex.c:19
#1: ffffffff899a56c0 (rcu_read_lock){....}, at: mutex_spin_on_owner+0x0/0x330 kernel/locking/mutex.c:413
#2: ffff8880a496a2b0 (&(&i->lock)->rlock){-.-.}, at: spin_lock include/linux/spinlock.h:338 [inline]
#2: ffff8880a496a2b0 (&(&i->lock)->rlock){-.-.}, at: serial8250_interrupt+0x2d/0x1a0 drivers/tty/serial/8250/8250_core.c:116
#3: ffffffff8c104048 (&port_lock_key){-.-.}, at: serial8250_handle_irq.part.0+0x24/0x330 drivers/tty/serial/8250/8250_port.c:1823
#4: ffff8880a905e090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref+0x22/0x90 drivers/tty/tty_ldisc.c:288
stack backtrace:
CPU: 1 PID: 9605 Comm: syz-executor826 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x197/0x210 lib/dump_stack.c:118
print_usage_bug.cold+0x327/0x378 kernel/locking/lockdep.c:3101
valid_state kernel/locking/lockdep.c:3112 [inline]
mark_lock_irq kernel/locking/lockdep.c:3309 [inline]
mark_lock+0xbb4/0x1220 kernel/locking/lockdep.c:3666
mark_usage kernel/locking/lockdep.c:3554 [inline]
__lock_acquire+0x1e55/0x4a00 kernel/locking/lockdep.c:3909
lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4485
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x32/0x50 kernel/locking/spinlock.c:223
sp_get.isra.0+0x1d/0xf0 drivers/net/ppp/ppp_synctty.c:138
sixpack_write_wakeup+0x25/0x340 drivers/net/hamradio/6pack.c:402
tty_wakeup+0xe9/0x120 drivers/tty/tty_io.c:536
tty_port_default_wakeup+0x2b/0x40 drivers/tty/tty_port.c:50
tty_port_tty_wakeup+0x57/0x70 drivers/tty/tty_port.c:387
uart_write_wakeup+0x46/0x70 drivers/tty/serial/serial_core.c:104
serial8250_tx_chars+0x495/0xaf0 drivers/tty/serial/8250/8250_port.c:1761
serial8250_handle_irq.part.0+0x2a2/0x330 drivers/tty/serial/8250/8250_port.c:1834
serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1820 [inline]
serial8250_default_handle_irq+0xc0/0x150 drivers/tty/serial/8250/8250_port.c:1850
serial8250_interrupt+0xf1/0x1a0 drivers/tty/serial/8250/8250_core.c:126
__handle_irq_event_percpu+0x15d/0x970 kernel/irq/handle.c:149
handle_irq_event_percpu+0x74/0x160 kernel/irq/handle.c:189
handle_irq_event+0xa7/0x134 kernel/irq/handle.c:206
handle_edge_irq+0x25e/0x8d0 kernel/irq/chip.c:830
generic_handle_irq_desc include/linux/irqdesc.h:156 [inline]
do_IRQ+0xde/0x280 arch/x86/kernel/irq.c:250
common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:607
</IRQ>
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:685 [inline]
RIP: 0010:mutex_spin_on_owner+0x247/0x330 kernel/locking/mutex.c:579
Code: c3 be 08 00 00 00 4c 89 e7 e8 e5 06 59 00 4c 89 e0 48 c1 e8 03 42 80 3c 38 00 0f 85 e1 00 00 00 49 8b 04 24 a8 01 75 96 f3 90 <e9> 2f fe ff ff 0f 0b e8 0d 19 09 00 84 c0 0f 85 ff fd ff ff 48 c7
RSP: 0018:ffffc90001eafa20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffd7
RAX: 0000000000000000 RBX: ffff88809fd9e0c0 RCX: 1ffffffff13266dd
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
RBP: ffffc90001eafa60 R08: 1ffff11013d22898 R09: ffffed1013d22899
R10: ffffed1013d22898 R11: ffff88809e9144c7 R12: ffff8880a905e138
R13: ffff88809e9144c0 R14: 0000000000000000 R15: dffffc0000000000
mutex_optimistic_spin kernel/locking/mutex.c:673 [inline]
__mutex_lock_common kernel/locking/mutex.c:962 [inline]
__mutex_lock+0x32b/0x13c0 kernel/locking/mutex.c:1106
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1121
tty_lock+0xc7/0x130 drivers/tty/tty_mutex.c:19
tty_release+0xb5/0xe90 drivers/tty/tty_io.c:1665
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
exit_task_work include/linux/task_work.h:22 [inline]
do_exit+0x8e7/0x2ef0 kernel/exit.c:797
do_group_exit+0x135/0x360 kernel/exit.c:895
__do_sys_exit_group kernel/exit.c:906 [inline]
__se_sys_exit_group kernel/exit.c:904 [inline]
__x64_sys_exit_group+0x44/0x50 kernel/exit.c:904
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43fef8
Code: Bad RIP value.
RSP: 002b:00007ffdb07d2338 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fef8
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004bf730 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000
Fixes: 6e4e2f8 ("6pack,mkiss: fix lock inconsistency")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
7 tasks
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