syzbot


KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter (4)

Status: auto-obsoleted due to no activity on 2022/10/19 09:26
Subsystems: kernel
[Documentation on labels]
First crash: 588d, last: 588d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter (2) kernel 19 1266d 1234d 0/26 auto-closed as invalid on 2020/12/21 11:36
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter (5) kernel 1 520d 520d 0/26 auto-obsoleted due to no activity on 2022/12/30 17:51
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter (6) kernel 3 438d 474d 0/26 auto-obsoleted due to no activity on 2023/03/31 04:54
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter kernel 18 1418d 1554d 0/26 closed as invalid on 2020/06/18 14:24
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter (3) kernel 43 688d 914d 0/26 auto-closed as invalid on 2022/07/11 12:52

Sample crash report:
==================================================================
BUG: KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter

write to 0xffff888237c1e0bc of 1 bytes by interrupt on cpu 0:
 tick_nohz_stop_idle kernel/time/tick-sched.c:665 [inline]
 tick_nohz_irq_enter kernel/time/tick-sched.c:1429 [inline]
 tick_irq_enter+0x152/0x210 kernel/time/tick-sched.c:1455
 sysvec_apic_timer_interrupt+0x80/0xb0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20
 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:112 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:555 [inline]
 acpi_idle_enter+0x283/0x310 drivers/acpi/processor_idle.c:692
 cpuidle_enter_state+0x2de/0x960 drivers/cpuidle/cpuidle.c:239
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:356
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x1a7/0x250 kernel/sched/idle.c:303
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400
 rest_init+0xe8/0xf0 init/main.c:727
 start_kernel+0x0/0x656 init/main.c:883
 start_kernel+0x5d1/0x656 init/main.c:1138
 secondary_startup_64_no_verify+0xcf/0xdb

read to 0xffff888237c1e0bc of 1 bytes by task 540 on cpu 1:
 get_cpu_iowait_time_us+0x68/0x1d0
 get_iowait_time fs/proc/stat.c:70 [inline]
 show_stat+0x60f/0xca0 fs/proc/stat.c:176
 seq_read_iter+0x2c3/0x8e0 fs/seq_file.c:230
 proc_reg_read_iter+0xd4/0x170 fs/proc/inode.c:301
 call_read_iter include/linux/fs.h:2181 [inline]
 io_iter_do_read io_uring/rw.c:643 [inline]
 io_read+0x2ec/0xc90 io_uring/rw.c:765
 io_issue_sqe+0x386/0x900 io_uring/io_uring.c:1577
 io_queue_sqe io_uring/io_uring.c:1755 [inline]
 io_submit_sqe+0x3b6/0xa40 io_uring/io_uring.c:2013
 io_submit_sqes+0x274/0x530 io_uring/io_uring.c:2124
 __do_sys_io_uring_enter io_uring/io_uring.c:3054 [inline]
 __se_sys_io_uring_enter+0x254/0xa50 io_uring/io_uring.c:2984
 __x64_sys_io_uring_enter+0x74/0x80 io_uring/io_uring.c:2984
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x05 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 540 Comm: syz-executor.4 Not tainted 6.0.0-rc5-syzkaller-00017-gd1221cea11fc-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/14 09:15 upstream d1221cea11fc b884348d .config console log report info [disk image] [vmlinux] ci2-upstream-kcsan-gce KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter
* Struck through repros no longer work on HEAD.