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KCSAN: data-race in tick_nohz_handler / tick_nohz_next_event

Status: auto-obsoleted due to no activity on 2024/05/18 07:30
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+ed3b6bb9978138dcd1e2@syzkaller.appspotmail.com
First crash: 43d, last: 35d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in tick_nohz_handler / tick_nohz_next_event

write to 0xffffffff86533330 of 4 bytes by interrupt on cpu 0:
 tick_sched_do_timer kernel/time/tick-sched.c:224 [inline]
 tick_nohz_handler+0x2bc/0x2d0 kernel/time/tick-sched.c:287
 __run_hrtimer kernel/time/hrtimer.c:1692 [inline]
 __hrtimer_run_queues+0x214/0x5e0 kernel/time/hrtimer.c:1756
 hrtimer_interrupt+0x210/0x7b0 kernel/time/hrtimer.c:1818
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
 acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
 acpi_idle_do_entry+0x1d/0x30 drivers/acpi/processor_idle.c:573
 acpi_idle_enter+0x96/0xb0 drivers/acpi/processor_idle.c:707
 cpuidle_enter_state+0xcf/0x270 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x40/0x70 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x195/0x230 kernel/sched/idle.c:332
 cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:430
 rest_init+0xef/0xf0 init/main.c:737
 start_kernel+0x57c/0x5e0 init/main.c:1079
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x12c/0x137

read to 0xffffffff86533330 of 4 bytes by task 0 on cpu 1:
 tick_nohz_next_event+0x1ee/0x2d0 kernel/time/tick-sched.c:950
 tick_nohz_get_sleep_length+0xac/0x110 kernel/time/tick-sched.c:1350
 menu_select+0x822/0x1070 drivers/cpuidle/governors/menu.c:286
 cpuidle_select+0x45/0x60 drivers/cpuidle/cpuidle.c:359
 cpuidle_idle_call kernel/sched/idle.c:229 [inline]
 do_idle+0x161/0x230 kernel/sched/idle.c:332
 cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:430
 start_secondary+0x94/0xa0 arch/x86/kernel/smpboot.c:313
 common_startup_64+0x12c/0x137

value changed: 0xffffffff -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.9.0-rc3-syzkaller-00344-g8f2c057754b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/13 07:30 upstream 8f2c057754b2 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in tick_nohz_handler / tick_nohz_next_event
2024/04/05 10:11 upstream c88b9b4cde17 0ee3535e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in tick_nohz_handler / tick_nohz_next_event
* Struck through repros no longer work on HEAD.