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KCSAN: data-race in hrtimer_reprogram / print_cpu

Status: auto-closed as invalid on 2020/05/29 16:43
Subsystems: kernel
[Documentation on labels]
First crash: 1490d, last: 1490d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (9) kernel 7 39d 94d 0/26 auto-obsoleted due to no activity on 2024/04/14 23:48
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (6) kernel 19 272d 457d 0/26 auto-obsoleted due to no activity on 2023/08/26 13:01
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (2) kernel 1 1324d 1324d 0/26 auto-closed as invalid on 2020/10/08 05:09
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (5) kernel 11 551d 634d 0/26 auto-obsoleted due to no activity on 2022/11/20 13:25
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (3) kernel 1 893d 893d 0/26 auto-closed as invalid on 2021/12/12 15:07
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (7) kernel 3 226d 236d 0/26 auto-obsoleted due to no activity on 2023/10/11 12:54
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (4) kernel 1 857d 857d 0/26 auto-closed as invalid on 2022/01/17 18:45
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (8) kernel 1 149d 129d 0/26 auto-obsoleted due to no activity on 2023/12/26 20:48

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

write to 0xffff88812c11fce0 of 8 bytes by task 7738 on cpu 1:
 hrtimer_reprogram+0x240/0x2b0 kernel/time/hrtimer.c:836
 hrtimer_start_range_ns+0x4bc/0x680 kernel/time/hrtimer.c:1134
 hrtimer_start_expires include/linux/hrtimer.h:435 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1795 [inline]
 do_nanosleep+0xfa/0x320 kernel/time/hrtimer.c:1871
 hrtimer_nanosleep+0x136/0x230 kernel/time/hrtimer.c:1927
 __do_sys_nanosleep kernel/time/hrtimer.c:1961 [inline]
 __se_sys_nanosleep kernel/time/hrtimer.c:1948 [inline]
 __x64_sys_nanosleep+0x14b/0x190 kernel/time/hrtimer.c:1948
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812c11fce0 of 8 bytes by task 12031 on cpu 0:
 print_cpu+0x22c/0x670 kernel/time/timer_list.c:148
 timer_list_show+0xb5/0x140 kernel/time/timer_list.c:311
 seq_read+0x346/0x9d0 fs/seq_file.c:229
 proc_reg_read+0xe8/0x140 fs/proc/inode.c:223
 do_loop_readv_writev fs/read_write.c:714 [inline]
 do_loop_readv_writev fs/read_write.c:701 [inline]
 do_iter_read+0x33d/0x3a0 fs/read_write.c:935
 vfs_readv+0x9c/0xf0 fs/read_write.c:1053
 kernel_readv fs/splice.c:365 [inline]
 default_file_splice_read+0x361/0x590 fs/splice.c:422
 do_splice_to+0xc7/0x100 fs/splice.c:892
 splice_direct_to_actor+0x1b9/0x540 fs/splice.c:971
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x396/0x810 fs/read_write.c:1520
 __do_sys_sendfile64 fs/read_write.c:1581 [inline]
 __se_sys_sendfile64 fs/read_write.c:1567 [inline]
 __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1567
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12031 Comm: syz-executor.4 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/03/20 16:36 https://github.com/google/ktsan.git kcsan 40959e34d670 2c31c529 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.