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KCSAN: data-race in futex_wait_queue_me / watchdog (2)

Status: auto-closed as invalid on 2020/06/18 14:03
Subsystems: kasan
[Documentation on labels]
First crash: 1569d, last: 1446d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in futex_wait_queue_me / watchdog kasan 1 1629d 1629d 0/26 closed as invalid on 2019/11/19 14:04

Sample crash report:
==================================================================
BUG: KCSAN: data-race in futex_wait_queue_me / watchdog

write to 0xffff888129cf8010 of 8 bytes by task 8902 on cpu 0:
 futex_wait_queue_me+0x1f5/0x290 kernel/futex.c:2633
 futex_wait+0x17e/0x3a0 kernel/futex.c:2737
 do_futex+0xe2/0x15b0 kernel/futex.c:3808
 __do_sys_futex kernel/futex.c:3869 [inline]
 __se_sys_futex kernel/futex.c:3837 [inline]
 __x64_sys_futex+0x2dc/0x410 kernel/futex.c:3837
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888129cf8010 of 8 bytes by task 1928 on cpu 1:
 check_hung_uninterruptible_tasks kernel/hung_task.c:197 [inline]
 watchdog+0x2b8/0x960 kernel/hung_task.c:289
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1928 Comm: khungtaskd Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 1928 Comm: khungtaskd Not tainted 5.7.0-rc1-syzkaller #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+0x11d/0x187 lib/dump_stack.c:118
 panic+0x210/0x640 kernel/panic.c:221
 kcsan_report.cold+0xc/0x1a kernel/kcsan/report.c:626
 kcsan_setup_watchpoint+0x3fb/0x440 kernel/kcsan/core.c:519
 check_hung_uninterruptible_tasks kernel/hung_task.c:197 [inline]
 watchdog+0x2b8/0x960 kernel/hung_task.c:289
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/09 14:08 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 88cb3e92 .config console log report ci2-upstream-kcsan-gce
2020/03/21 23:55 https://github.com/google/ktsan.git kcsan 40959e34d670 78267cec .config console log report ci2-upstream-kcsan-gce
2020/01/14 05:35 https://github.com/google/ktsan.git kcsan 245a43005292 32881205 .config console log report ci2-upstream-kcsan-gce
2020/01/06 22:12 https://github.com/google/ktsan.git kcsan 245a43005292 53430d97 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.