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KCSAN: data-race in futex_wait / hrtimer_wakeup (6)

Status: auto-obsoleted due to no activity on 2023/08/26 06:58
Subsystems: kernel
[Documentation on labels]
First crash: 346d, last: 288d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in futex_wait / hrtimer_wakeup (5) kernel 2 407d 451d 0/26 auto-obsoleted due to no activity on 2023/04/29 18:45
upstream KCSAN: data-race in futex_wait / hrtimer_wakeup (2) kernel 1 994d 994d 0/26 auto-closed as invalid on 2021/09/19 05:49
upstream KCSAN: data-race in futex_wait / hrtimer_wakeup (4) kernel 1 716d 716d 0/26 auto-closed as invalid on 2022/06/24 14:54
upstream KCSAN: data-race in futex_wait / hrtimer_wakeup kernel 2 1148d 1177d 0/26 auto-closed as invalid on 2021/05/17 11:26
upstream KCSAN: data-race in futex_wait / hrtimer_wakeup (3) kernel 1 797d 797d 0/26 auto-closed as invalid on 2022/04/04 11:03

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

read-write to 0xffffc9000cc27db0 of 8 bytes by interrupt on cpu 0:
 hrtimer_wakeup+0x1c/0x50 kernel/time/hrtimer.c:1940
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x217/0x700 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x20d/0x7b0 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline]
 __sysvec_apic_timer_interrupt+0x73/0x210 arch/x86/kernel/apic/apic.c:1115
 sysvec_apic_timer_interrupt+0x68/0x80 arch/x86/kernel/apic/apic.c:1109
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x2f/0x40 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0xc54/0xff0 kernel/signal.c:2880
 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:308
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffc9000cc27db0 of 8 bytes by task 7596 on cpu 1:
 futex_wait+0x1d8/0x410 kernel/futex/waitwake.c:663
 do_futex+0x287/0x370 kernel/futex/syscalls.c:106
 __do_sys_futex kernel/futex/syscalls.c:183 [inline]
 __se_sys_futex+0x25d/0x3a0 kernel/futex/syscalls.c:164
 __x64_sys_futex+0x78/0x90 kernel/futex/syscalls.c:164
 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: 0xffff888135212080 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7596 Comm: syz-executor.2 Not tainted 6.5.0-rc2-syzkaller-00307-gd192f5382581 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/22 06:50 upstream d192f5382581 abdf9bae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in futex_wait / hrtimer_wakeup
2023/07/05 11:36 upstream d528014517f2 80298b6f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in futex_wait / hrtimer_wakeup
2023/06/19 12:37 upstream 45a3e24f65e9 d521bc56 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in futex_wait / hrtimer_wakeup
2023/05/25 12:22 upstream 933174ae28ba 0513b3e6 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in futex_wait / hrtimer_wakeup
* Struck through repros no longer work on HEAD.