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KCSAN: data-race in __remove_hrtimer / hrtimer_active (2)

Status: closed as invalid on 2019/11/19 14:04
Subsystems: kernel
[Documentation on labels]
First crash: 1630d, last: 1630d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __remove_hrtimer / hrtimer_active kernel 1 1656d 1656d 0/26 closed as invalid on 2019/10/18 14:11
upstream KCSAN: data-race in __remove_hrtimer / hrtimer_active (3) kernel 2 1596d 1601d 0/26 auto-closed as invalid on 2020/02/20 07:07

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

read to 0xffff8881008bd8b0 of 1 bytes by task 10403 on cpu 0:
 hrtimer_active+0x5e/0x1a0 kernel/time/hrtimer.c:1445
 hrtimer_try_to_cancel+0x3c/0x260 kernel/time/hrtimer.c:1160
 common_hrtimer_try_to_cancel+0x21/0x40 kernel/time/posix-timers.c:805
 common_timer_set+0x76/0x2b0 kernel/time/posix-timers.c:855
 do_timer_settime.part.0+0xaa/0x160 kernel/time/posix-timers.c:901
 do_timer_settime kernel/time/posix-timers.c:916 [inline]
 __do_sys_timer_settime kernel/time/posix-timers.c:930 [inline]
 __se_sys_timer_settime kernel/time/posix-timers.c:916 [inline]
 __x64_sys_timer_settime+0x1ab/0x250 kernel/time/posix-timers.c:916
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8881008bd8b0 of 1 bytes by interrupt on cpu 1:
 __remove_hrtimer+0x52/0x130 kernel/time/hrtimer.c:991
 __run_hrtimer kernel/time/hrtimer.c:1496 [inline]
 __hrtimer_run_queues+0x23c/0x5f0 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 arch_local_irq_restore arch/x86/include/asm/paravirt.h:756 [inline]
 kcsan_setup_watchpoint+0x205/0x410 kernel/kcsan/core.c:369
 check_access kernel/kcsan/core.c:409 [inline]
 __tsan_unaligned_write8+0x143/0x1f0 kernel/kcsan/core.c:530
 futex_wake+0x7c/0x350 kernel/futex.c:1601
 do_futex+0x2be/0x18d0 kernel/futex.c:3649
 __do_sys_futex kernel/futex.c:3705 [inline]
 __se_sys_futex kernel/futex.c:3673 [inline]
 __x64_sys_futex+0x2cd/0x3f0 kernel/futex.c:3673
 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: 10341 Comm: syz-executor.2 Not tainted 5.4.0-rc6+ #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
2019/11/08 11:12 https://github.com/google/ktsan.git kcsan 94c006602e13 1e35461e .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.