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KCSAN: data-race in __remove_hrtimer / hrtimer_active

Status: closed as invalid on 2019/10/18 14:11
Subsystems: kernel
[Documentation on labels]
First crash: 1649d, last: 1649d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __remove_hrtimer / hrtimer_active (3) kernel 2 1589d 1594d 0/26 auto-closed as invalid on 2020/02/20 07:07
upstream KCSAN: data-race in __remove_hrtimer / hrtimer_active (2) kernel 1 1623d 1623d 0/26 closed as invalid on 2019/11/19 14:04

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __remove_hrtimer / hrtimer_active

read to 0xffffc9000163fc88 of 1 bytes by task 7189 on cpu 1:
 hrtimer_active+0x5e/0x1a0 kernel/time/hrtimer.c:1320
 hrtimer_try_to_cancel+0x3c/0x260 kernel/time/hrtimer.c:1135
 hrtimer_cancel+0x29/0x50 kernel/time/hrtimer.c:1161
 futex_wait+0x38b/0x400 kernel/futex.c:2769
 do_futex+0xe9/0x18b0 kernel/futex.c:3646
 __do_sys_futex kernel/futex.c:3707 [inline]
 __se_sys_futex kernel/futex.c:3675 [inline]
 __x64_sys_futex+0x2cd/0x3f0 kernel/futex.c:3675
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffffc9000163fc88 of 1 bytes by interrupt on cpu 0:
 __remove_hrtimer+0x52/0x130 kernel/time/hrtimer.c:970
 __run_hrtimer kernel/time/hrtimer.c:1371 [inline]
 __hrtimer_run_queues+0x250/0x600 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7204 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 7204 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xf5/0x159 lib/dump_stack.c:113
 panic+0x209/0x639 kernel/panic.c:219
 kcsan_report.cold+0xc/0x1b kernel/kcsan/report.c:303
 __kcsan_setup_watchpoint+0x3ee/0x510 kernel/kcsan/core.c:455
 __tsan_write1 kernel/kcsan/kcsan.c:28 [inline]
 __tsan_write1+0x32/0x40 kernel/kcsan/kcsan.c:28
 __remove_hrtimer+0x52/0x130 kernel/time/hrtimer.c:970
 __run_hrtimer kernel/time/hrtimer.c:1371 [inline]
 __hrtimer_run_queues+0x250/0x600 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 </IRQ>
RIP: 0033:0x40ac38
Code: 4d 89 c8 eb de 49 89 d2 4a 8d 54 8a 08 8b 12 44 8b 5c 24 58 44 39 da 74 05 4c 89 d2 eb c5 0f b6 46 52 4c 0f af c8 0f b6 43 08 <4b> 8d 4c 11 28 a8 04 0f 84 da 01 00 00 83 e0 fb 88 43 08 48 89 4c
RSP: 002b:000000c4204e18d8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000004 RBX: 000000c42098d200 RCX: 000000c4209db6f0
RDX: 00000000a8d1a69e RSI: 00000000008630e0 RDI: 0000000000000100
RBP: 000000c4204e1910 R08: 0000000000000000 R09: 0000000000000000
R10: 000000c4209db6e8 R11: 0000000000000680 R12: 0000000000000180
R13: 0000000000000018 R14: 0000000000000057 R15: 0000000000000100
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/13 11:29 https://github.com/google/ktsan.git kcsan d724f94f63de 2f661ec4 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.