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

Status: auto-obsoleted due to no activity on 2023/05/23 02:49
Subsystems: kernel
[Documentation on labels]
First crash: 380d, last: 380d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in print_cpu / tick_irq_enter kernel 2 909d 940d 0/26 auto-closed as invalid on 2021/12/09 16:37
upstream KCSAN: data-race in print_cpu / tick_irq_enter (3) kernel 1 577d 577d 0/26 auto-obsoleted due to no activity on 2022/11/06 07:20
upstream KCSAN: data-race in print_cpu / tick_irq_enter (2) kernel 1 633d 633d 0/26 auto-closed as invalid on 2022/09/11 23:24

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

read-write to 0xffff888237d1f300 of 8 bytes by interrupt on cpu 1:
 tick_nohz_stop_idle kernel/time/tick-sched.c:664 [inline]
 tick_nohz_irq_enter kernel/time/tick-sched.c:1429 [inline]
 tick_irq_enter+0xed/0x1d0 kernel/time/tick-sched.c:1455
 sysvec_apic_timer_interrupt+0x60/0x80 arch/x86/kernel/apic/apic.c:1107
 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+0x194/0x240 kernel/sched/idle.c:282
 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379
 start_secondary+0x7c/0x80 arch/x86/kernel/smpboot.c:264
 secondary_startup_64_no_verify+0xcf/0xdb

read to 0xffff888237d1f300 of 8 bytes by task 10122 on cpu 0:
 print_cpu+0x52b/0x630 kernel/time/timer_list.c:161
 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:1845 [inline]
 generic_file_splice_read+0xe3/0x290 fs/splice.c:402
 do_splice_to fs/splice.c:885 [inline]
 splice_direct_to_actor+0x25a/0x5f0 fs/splice.c:956
 do_splice_direct+0x104/0x180 fs/splice.c:1065
 do_sendfile+0x3b8/0x950 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1309
 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: 0x00000011346745ae -> 0x00000011347131f7

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10122 Comm: syz-executor.1 Not tainted 6.3.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/18 02:47 upstream 6a8f57ae2eb0 436577a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in print_cpu / tick_irq_enter
* Struck through repros no longer work on HEAD.