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KCSAN: data-race in hrtimer_reprogram / print_cpu (7)

Status: auto-obsoleted due to no activity on 2023/10/11 12:54
Subsystems: kernel
[Documentation on labels]
First crash: 249d, last: 239d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (9) kernel 7 53d 108d 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 285d 470d 0/26 auto-obsoleted due to no activity on 2023/08/26 13:01
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu kernel 1 1504d 1504d 0/26 auto-closed as invalid on 2020/05/29 16:43
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (2) kernel 1 1337d 1337d 0/26 auto-closed as invalid on 2020/10/08 05:09
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (5) kernel 11 564d 647d 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 907d 907d 0/26 auto-closed as invalid on 2021/12/12 15:07
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (10) kernel 2 5d06h 6d13h 0/26 moderation: reported on 2024/04/26 11:32
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (4) kernel 1 871d 871d 0/26 auto-closed as invalid on 2022/01/17 18:45
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (8) kernel 1 163d 143d 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 0xffff888237d1ede0 of 8 bytes by task 4964 on cpu 1:
 __hrtimer_reprogram kernel/time/hrtimer.c:661 [inline]
 hrtimer_reprogram+0x1bd/0x230 kernel/time/hrtimer.c:868
 hrtimer_start_range_ns+0x4e8/0x660 kernel/time/hrtimer.c:1302
 hrtimer_start_expires include/linux/hrtimer.h:432 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1968 [inline]
 do_nanosleep+0x85/0x2f0 kernel/time/hrtimer.c:2044
 hrtimer_nanosleep+0xe7/0x1e0 kernel/time/hrtimer.c:2100
 common_nsleep+0x68/0x80 kernel/time/posix-timers.c:1350
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline]
 __se_sys_clock_nanosleep+0x202/0x230 kernel/time/posix-timers.c:1373
 __x64_sys_clock_nanosleep+0x55/0x60 kernel/time/posix-timers.c:1373
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888237d1ede0 of 8 bytes by task 7464 on cpu 0:
 print_cpu+0x2fb/0x640 kernel/time/timer_list.c:133
 timer_list_show+0x115/0x180 kernel/time/timer_list.c:291
 seq_read_iter+0x612/0x8f0 fs/seq_file.c:272
 proc_reg_read_iter+0x114/0x180 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:1979 [inline]
 copy_splice_read+0x26b/0x4b0 fs/splice.c:364
 vfs_splice_read fs/splice.c:993 [inline]
 splice_direct_to_actor+0x28c/0x690 fs/splice.c:1069
 do_splice_direct+0x10d/0x190 fs/splice.c:1194
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000016257b67c80 -> 0x0000016257a0a2eb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7464 Comm: syz-executor.5 Not tainted 6.5.0-syzkaller-11938-g65d6e954e378 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/06 12:48 upstream 65d6e954e378 0b6286dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2023/09/01 12:09 upstream 99d99825fc07 696ea0d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2023/08/27 09:17 upstream 3b35375f19fe 7ba13a15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
* Struck through repros no longer work on HEAD.