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KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kernel
[Documentation on labels]
First crash: 1555d, last: 1420d
▶ ▼ 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 1267d 1235d 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 521d 521d 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 440d 476d 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 (3) kernel 43 689d 915d 0/26 auto-closed as invalid on 2022/07/11 12:52
upstream KCSAN: data-race in get_cpu_iowait_time_us / tick_irq_enter (4) kernel 1 589d 589d 0/26 auto-obsoleted due to no activity on 2022/10/19 09:26

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

write to 0xffff88812c12030c of 1 bytes by task 0 on cpu 1:
 tick_nohz_stop_idle kernel/time/tick-sched.c:557 [inline]
 tick_nohz_irq_enter kernel/time/tick-sched.c:1276 [inline]
 tick_irq_enter+0x17b/0x1b0 kernel/time/tick-sched.c:1295
 irq_enter+0x49/0x50 kernel/softirq.c:354
 entering_irq arch/x86/include/asm/apic.h:527 [inline]
 entering_ack_irq arch/x86/include/asm/apic.h:533 [inline]
 smp_apic_timer_interrupt+0x52/0x270 arch/x86/kernel/apic/apic.c:1136
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
 arch_safe_halt arch/x86/include/asm/paravirt.h:144 [inline]
 default_idle+0x21/0x170 arch/x86/kernel/process.c:697
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x1b7/0x290 kernel/sched/idle.c:269
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361
 start_secondary+0x169/0x1b0 arch/x86/kernel/smpboot.c:268
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242

read to 0xffff88812c12030c of 1 bytes by task 15120 on cpu 0:
 get_cpu_iowait_time_us+0xe5/0x170 kernel/time/tick-sched.c:637
 get_iowait_time.isra.0+0x65/0x90 fs/proc/stat.c:69
 show_stat+0x633/0xa50 fs/proc/stat.c:173
 seq_read+0x2ef/0x940 fs/seq_file.c:206
 pde_read fs/proc/inode.c:292 [inline]
 proc_reg_read+0xb3/0x1b0 fs/proc/inode.c:302
 do_loop_readv_writev fs/read_write.c:715 [inline]
 do_loop_readv_writev fs/read_write.c:702 [inline]
 do_iter_read+0x33f/0x3a0 fs/read_write.c:936
 vfs_readv+0x9c/0xf0 fs/read_write.c:1054
 do_preadv+0x129/0x1c0 fs/read_write.c:1146
 __do_sys_preadv fs/read_write.c:1196 [inline]
 __se_sys_preadv fs/read_write.c:1191 [inline]
 __x64_sys_preadv+0x5e/0x80 fs/read_write.c:1191
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15120 Comm: syz-executor.5 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/06 07:27 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 c3e9afb3 .config console log report ci2-upstream-kcsan-gce
2020/05/19 15:46 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6d882fd2 .config console log report ci2-upstream-kcsan-gce
2020/05/09 17:04 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 88cb3e92 .config console log report ci2-upstream-kcsan-gce
2020/04/25 10:04 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a113ba38 .config console log report ci2-upstream-kcsan-gce
2020/04/15 02:44 https://github.com/google/ktsan.git kcsan 40959e34d670 3f3c5574 .config console log report ci2-upstream-kcsan-gce
2020/04/11 17:11 https://github.com/google/ktsan.git kcsan 40959e34d670 a8c6a3f8 .config console log report ci2-upstream-kcsan-gce
2020/04/01 15:29 https://github.com/google/ktsan.git kcsan 40959e34d670 a34e2c33 .config console log report ci2-upstream-kcsan-gce
2020/03/24 08:41 https://github.com/google/ktsan.git kcsan 40959e34d670 33e14df3 .config console log report ci2-upstream-kcsan-gce
2020/03/13 22:57 https://github.com/google/ktsan.git kcsan 941e0d917bbf 749688d2 .config console log report ci2-upstream-kcsan-gce
2020/03/11 12:48 https://github.com/google/ktsan.git kcsan 941e0d917bbf e103bc9e .config console log report ci2-upstream-kcsan-gce
2020/03/10 13:31 https://github.com/google/ktsan.git kcsan 941e0d917bbf 35f53e45 .config console log report ci2-upstream-kcsan-gce
2020/03/08 15:39 https://github.com/google/ktsan.git kcsan 941e0d917bbf 2e9971bb .config console log report ci2-upstream-kcsan-gce
2020/02/26 15:13 https://github.com/google/ktsan.git kcsan 766d004d1b85 251aabb7 .config console log report ci2-upstream-kcsan-gce
2020/02/20 23:02 https://github.com/google/ktsan.git kcsan b12d66a6c34f 81230308 .config console log report ci2-upstream-kcsan-gce
2020/02/05 15:25 https://github.com/google/ktsan.git kcsan 245a43005292 662cf49a .config console log report ci2-upstream-kcsan-gce
2020/02/05 12:25 https://github.com/google/ktsan.git kcsan 245a43005292 93e5e335 .config console log report ci2-upstream-kcsan-gce
2020/01/30 22:09 https://github.com/google/ktsan.git kcsan 245a43005292 5ed23f9a .config console log report ci2-upstream-kcsan-gce
2020/01/22 09:44 https://github.com/google/ktsan.git kcsan 245a43005292 8eda0b95 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.