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KCSAN: data-race in osq_lock / osq_lock

Status: closed as invalid on 2019/11/19 14:54
Subsystems: mm
[Documentation on labels]
First crash: 1647d, last: 1628d
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in osq_lock / osq_lock (2) mm 1 1592d 1592d 0/26 closed as invalid on 2020/01/23 11:36

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

write to 0xffff88812be2b054 of 4 bytes by task 22921 on cpu 0:
 osq_lock+0x89/0x2f0 kernel/locking/osq_lock.c:99
 rwsem_optimistic_spin+0x5f/0x320 kernel/locking/rwsem.c:800
 rwsem_down_write_slowpath+0x109/0x950 kernel/locking/rwsem.c:1150
 __down_write kernel/locking/rwsem.c:1392 [inline]
 down_write+0x88/0x90 kernel/locking/rwsem.c:1535
 i_mmap_lock_write include/linux/fs.h:526 [inline]
 unlink_file_vma+0x5b/0x90 mm/mmap.c:168
 free_pgtables+0x14f/0x200 mm/memory.c:396
 exit_mmap+0x151/0x300 mm/mmap.c:3162
 __mmput kernel/fork.c:1079 [inline]
 mmput+0xea/0x280 kernel/fork.c:1100
 exit_mm kernel/exit.c:485 [inline]
 do_exit+0x4c9/0x18f0 kernel/exit.c:804
 do_group_exit+0xb4/0x1c0 kernel/exit.c:921
 __do_sys_exit_group kernel/exit.c:932 [inline]
 __se_sys_exit_group kernel/exit.c:930 [inline]
 __x64_sys_exit_group+0x2e/0x30 kernel/exit.c:930
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812be2b054 of 4 bytes by task 18829 on cpu 1:
 osq_lock+0x170/0x2f0 kernel/locking/osq_lock.c:143
 rwsem_optimistic_spin+0x5f/0x320 kernel/locking/rwsem.c:800
 rwsem_down_write_slowpath+0x109/0x950 kernel/locking/rwsem.c:1150
 __down_write kernel/locking/rwsem.c:1392 [inline]
 down_write+0x88/0x90 kernel/locking/rwsem.c:1535
 i_mmap_lock_write include/linux/fs.h:526 [inline]
 dup_mmap kernel/fork.c:568 [inline]
 dup_mm+0x4f7/0xba0 kernel/fork.c:1361
 copy_mm kernel/fork.c:1417 [inline]
 copy_process+0x36f3/0x3b50 kernel/fork.c:2012
 _do_fork+0xfe/0x6e0 kernel/fork.c:2366
 __do_sys_clone kernel/fork.c:2521 [inline]
 __se_sys_clone kernel/fork.c:2502 [inline]
 __x64_sys_clone+0x12b/0x160 kernel/fork.c:2502
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18829 Comm: syz-executor.5 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/11 19:41 https://github.com/google/ktsan.git kcsan 94c006602e13 377d77fa .config console log report ci2-upstream-kcsan-gce
2019/11/09 23:13 https://github.com/google/ktsan.git kcsan 94c006602e13 dc438b91 .config console log report ci2-upstream-kcsan-gce
2019/11/08 18:22 https://github.com/google/ktsan.git kcsan 94c006602e13 1e35461e .config console log report ci2-upstream-kcsan-gce
2019/11/07 18:10 https://github.com/google/ktsan.git kcsan 94c006602e13 f39aff9e .config console log report ci2-upstream-kcsan-gce
2019/11/07 05:13 https://github.com/google/ktsan.git kcsan 94c006602e13 d797d201 .config console log report ci2-upstream-kcsan-gce
2019/11/06 17:43 https://github.com/google/ktsan.git kcsan 94c006602e13 da505f84 .config console log report ci2-upstream-kcsan-gce
2019/11/06 06:00 https://github.com/google/ktsan.git kcsan 94c006602e13 bc2c6e45 .config console log report ci2-upstream-kcsan-gce
2019/11/05 14:22 https://github.com/google/ktsan.git kcsan 94c006602e13 af5c522d .config console log report ci2-upstream-kcsan-gce
2019/11/05 13:24 https://github.com/google/ktsan.git kcsan 94c006602e13 0f3ec414 .config console log report ci2-upstream-kcsan-gce
2019/11/05 06:07 https://github.com/google/ktsan.git kcsan 94c006602e13 76630fc9 .config console log report ci2-upstream-kcsan-gce
2019/11/04 21:29 https://github.com/google/ktsan.git kcsan 94c006602e13 18e12644 .config console log report ci2-upstream-kcsan-gce
2019/11/04 14:00 https://github.com/google/ktsan.git kcsan 05f2236801fe 18e12644 .config console log report ci2-upstream-kcsan-gce
2019/11/04 04:17 https://github.com/google/ktsan.git kcsan 05f2236801fe b35fad31 .config console log report ci2-upstream-kcsan-gce
2019/11/04 04:03 https://github.com/google/ktsan.git kcsan 05f2236801fe b35fad31 .config console log report ci2-upstream-kcsan-gce
2019/11/04 03:58 https://github.com/google/ktsan.git kcsan 05f2236801fe b35fad31 .config console log report ci2-upstream-kcsan-gce
2019/11/03 15:16 https://github.com/google/ktsan.git kcsan 05f2236801fe c9610487 .config console log report ci2-upstream-kcsan-gce
2019/11/02 21:34 https://github.com/google/ktsan.git kcsan 05f2236801fe d603afc9 .config console log report ci2-upstream-kcsan-gce
2019/11/01 19:52 https://github.com/google/ktsan.git kcsan 05f2236801fe 997ccc67 .config console log report ci2-upstream-kcsan-gce
2019/10/30 23:33 https://github.com/google/ktsan.git kcsan 05f2236801fe a41ca8fa .config console log report ci2-upstream-kcsan-gce
2019/10/29 05:24 https://github.com/google/ktsan.git kcsan 05f2236801fe 5ea87a66 .config console log report ci2-upstream-kcsan-gce
2019/10/28 18:20 https://github.com/google/ktsan.git kcsan 05f2236801fe 439d7b14 .config console log report ci2-upstream-kcsan-gce
2019/10/26 13:39 https://github.com/google/ktsan.git kcsan 05f2236801fe 25bb509e .config console log report ci2-upstream-kcsan-gce
2019/10/26 00:43 https://github.com/google/ktsan.git kcsan 05f2236801fe 413926c5 .config console log report ci2-upstream-kcsan-gce
2019/10/25 12:18 https://github.com/google/ktsan.git kcsan 05f2236801fe 04ca72cd .config console log report ci2-upstream-kcsan-gce
2019/10/24 11:11 https://github.com/google/ktsan.git kcsan 05f2236801fe d01bb02a .config console log report ci2-upstream-kcsan-gce
2019/10/23 19:29 https://github.com/google/ktsan.git kcsan 05f2236801fe b602d64b .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.