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KCSAN: data-race in clockevents_program_min_delta / print_tickdevice (4)

Status: auto-obsoleted due to no activity on 2024/09/08 12:24
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+216b245d7c9f92402d7f@syzkaller.appspotmail.com
First crash: 39d, last: 39d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in clockevents_program_min_delta / print_tickdevice (3) kernel 1 487d 487d 0/27 auto-obsoleted due to no activity on 2023/06/18 09:00
upstream KCSAN: data-race in clockevents_program_min_delta / print_tickdevice kernel 2 722d 723d 0/27 auto-obsoleted due to no activity on 2022/10/25 15:55
upstream KCSAN: data-race in clockevents_program_min_delta / print_tickdevice (2) kernel 6 544d 665d 0/27 auto-obsoleted due to no activity on 2023/04/25 16:15

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

read-write to 0xffff888237c1c240 of 8 bytes by task 10879 on cpu 0:
 clockevents_program_min_delta+0xb6/0x260 kernel/time/clockevents.c:246
 clockevents_program_event+0x180/0x1f0
 tick_program_event+0x7c/0xd0 kernel/time/tick-oneshot.c:44
 __hrtimer_reprogram kernel/time/hrtimer.c:679 [inline]
 hrtimer_reprogram+0x1cf/0x220 kernel/time/hrtimer.c:864
 hrtimer_start_range_ns+0x512/0x580 kernel/time/hrtimer.c:1303
 hrtimer_start_expires include/linux/hrtimer.h:289 [inline]
 hrtimer_restart include/linux/hrtimer.h:297 [inline]
 common_hrtimer_rearm+0xa6/0xc0 kernel/time/posix-timers.c:249
 posixtimer_rearm+0xc7/0x1a0 kernel/time/posix-timers.c:267
 dequeue_signal+0x282/0x430 kernel/signal.c:696
 get_signal+0x37d/0x1080 kernel/signal.c:2796
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x59/0x130 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c1c240 of 8 bytes by task 10899 on cpu 1:
 print_tickdevice+0x2ae/0x340 kernel/time/timer_list.c:234
 timer_list_show+0x79/0x180 kernel/time/timer_list.c:300
 seq_read_iter+0x65b/0x940 fs/seq_file.c:272
 proc_reg_read_iter+0x11e/0x190 fs/proc/inode.c:299
 copy_splice_read+0x3a4/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x950 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000335279 -> 0x000000000033527c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10899 Comm: syz.1.1736 Tainted: G        W          6.11.0-rc1-syzkaller-00293-gdefaf1a2113a #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/04 12:24 upstream defaf1a2113a 1786a2a8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in clockevents_program_min_delta / print_tickdevice
* Struck through repros no longer work on HEAD.