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KCSAN: data-race in print_cpu / tick_nohz_stop_idle

Status: auto-obsoleted due to no activity on 2023/06/11 20:07
Subsystems: kernel
[Documentation on labels]
First crash: 408d, last: 408d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in print_cpu / tick_nohz_stop_idle (2) kernel 2 305d 310d 0/27 auto-obsoleted due to no activity on 2023/09/22 19:10
upstream KCSAN: data-race in print_cpu / tick_nohz_stop_idle (3) kernel 6 6d10h 58d 0/27 moderation: reported on 2024/04/21 02:19

Sample crash report:
==================================================================
BUG: KCSAN: data-race in print_cpu / tick_nohz_stop_idle

write to 0xffff888237c1f2e8 of 8 bytes by interrupt on cpu 0:
 tick_nohz_stop_idle+0xb1/0x100 kernel/time/tick-sched.c:665
 tick_nohz_irq_enter kernel/time/tick-sched.c:1430 [inline]
 tick_irq_enter+0x96/0x140 kernel/time/tick-sched.c:1456
 sysvec_apic_timer_interrupt+0x60/0x80 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 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+0x20/0x30 drivers/acpi/processor_idle.c:112
 acpi_idle_do_entry+0x19/0x30 drivers/acpi/processor_idle.c:573
 acpi_idle_enter+0x96/0xb0 drivers/acpi/processor_idle.c:711
 cpuidle_enter_state+0xc6/0x260 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x40/0x60 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:134 [inline]
 cpuidle_idle_call kernel/sched/idle.c:215 [inline]
 do_idle+0x194/0x230 kernel/sched/idle.c:282
 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379
 rest_init+0xf3/0x100 init/main.c:735
 arch_call_rest_init+0x9/0x10 init/main.c:834
 start_kernel+0x582/0x5e0 init/main.c:1088
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:556
 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:537
 secondary_startup_64_no_verify+0xf5/0xfb

read to 0xffff888237c1f2e8 of 8 bytes by task 8748 on cpu 1:
 print_cpu+0x4c4/0x640 kernel/time/timer_list.c:158
 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+0x10e/0x180 fs/proc/inode.c:305
 call_read_iter include/linux/fs.h:1862 [inline]
 generic_file_splice_read+0xe3/0x290 fs/splice.c:419
 do_splice_to fs/splice.c:902 [inline]
 splice_direct_to_actor+0x25a/0x5f0 fs/splice.c:973
 do_splice_direct+0x104/0x180 fs/splice.c:1082
 do_sendfile+0x3b8/0x950 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: 0x00000026bd426e7b -> 0x00000026bd438972

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8748 Comm: syz-executor.2 Not tainted 6.3.0-syzkaller-13505-g17784de648be #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/07 20:02 upstream 17784de648be 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_nohz_stop_idle
* Struck through repros no longer work on HEAD.