syzbot


KCSAN: data-race in __run_timers / internal_add_timer (2)

Status: auto-closed as invalid on 2021/12/12 01:16
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 423d, last: 386d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __run_timers / internal_add_timer 14 475d 580d 0/24 auto-closed as invalid on 2021/09/14 04:57

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __run_timers / internal_add_timer

write to 0xffff888237d1b858 of 8 bytes by interrupt on cpu 0:
 enqueue_timer kernel/time/timer.c:598 [inline]
 internal_add_timer+0x14f/0x2b0 kernel/time/timer.c:611
 add_timer_on+0x247/0x280 kernel/time/timer.c:1182
 clocksource_watchdog+0xa96/0xac0 kernel/time/clocksource.c:478
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1421
 expire_timers+0x116/0x240 kernel/time/timer.c:1466
 __run_timers+0x368/0x410 kernel/time/timer.c:1734
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1747
 __do_softirq+0x158/0x2de kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x37/0x70 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:553 [inline]
 acpi_idle_enter+0x282/0x300 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x2b4/0x7d0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x1b2/0x250 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 rest_init+0xfa/0x100 init/main.c:725
 arch_call_rest_init+0xa/0xb
 start_kernel+0x5e4/0x669 init/main.c:1133
 secondary_startup_64_no_verify+0xb1/0xbb

read to 0xffff888237d1b858 of 8 bytes by interrupt on cpu 1:
 __run_timers+0x62/0x410 kernel/time/timer.c:1715
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1747
 __do_softirq+0x158/0x2de kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x37/0x70 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:553 [inline]
 acpi_idle_enter+0x282/0x300 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x2b4/0x7d0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x1b2/0x250 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb1/0xbb

value changed: 0x000000010000cd48 -> 0x000000010000cd15

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/11/07 01:14 upstream 512b7931ad05 4c1be0be .config log report info KCSAN: data-race in __run_timers / internal_add_timer
ci2-upstream-kcsan-gce 2021/11/05 06:08 upstream d4439a1189f9 4c1be0be .config log report info KCSAN: data-race in __run_timers / internal_add_timer
ci2-upstream-kcsan-gce 2021/10/30 01:35 upstream a379fbbcb88b 098b5d53 .config log report info KCSAN: data-race in __run_timers / internal_add_timer
ci2-upstream-kcsan-gce 2021/09/30 19:29 upstream 02d5e016800d 0f01403d .config log report info KCSAN: data-race in __run_timers / internal_add_timer
* Struck through repros no longer work on HEAD.