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KCSAN: data-race in tick_nohz_next_event / tick_sched_do_timer

Status: closed as invalid on 2019/10/18 14:11
Subsystems: kernel
[Documentation on labels]
First crash: 1662d, last: 1655d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in tick_nohz_next_event / tick_sched_do_timer (3) kernel 73 1408d 1438d 0/26 auto-closed as invalid on 2020/07/23 12:47
upstream KCSAN: data-race in tick_nohz_next_event / tick_sched_do_timer (2) kernel 9 1623d 1650d 0/26 closed as invalid on 2019/11/19 14:04

Sample crash report:
==================================================================
BUG: KCSAN: data-race in tick_nohz_next_event / tick_sched_do_timer

write to 0xffffffff85caf310 of 4 bytes by interrupt on cpu 0:
 tick_sched_do_timer+0xc0/0xe0 kernel/time/tick-sched.c:132
 tick_sched_timer+0x43/0xe0 kernel/time/tick-sched.c:1289
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x288/0x600 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
 arch_local_irq_restore arch/x86/include/asm/paravirt.h:768 [inline]
 __kcsan_setup_watchpoint+0x282/0x510 kernel/kcsan/core.c:469
 __tsan_read8 kernel/kcsan/kcsan.c:31 [inline]
 __tsan_read8+0x2c/0x30 kernel/kcsan/kcsan.c:31
 nf_ct_seq_offset+0x2e/0xd0 net/netfilter/nf_conntrack_seqadj.c:224
 tcp_in_window net/netfilter/nf_conntrack_proto_tcp.c:492 [inline]
 nf_conntrack_tcp_packet+0x5d9/0x3390 net/netfilter/nf_conntrack_proto_tcp.c:1091
 nf_conntrack_handle_packet net/netfilter/nf_conntrack_core.c:1633 [inline]
 nf_conntrack_in+0x410/0xaa0 net/netfilter/nf_conntrack_core.c:1727
 ipv4_conntrack_in+0x27/0x40 net/netfilter/nf_conntrack_proto.c:178
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 ip_rcv+0x12f/0x1a0 net/ipv4/ip_input.c:523

read to 0xffffffff85caf310 of 4 bytes by task 0 on cpu 1:
 tick_nohz_next_event+0x1a4/0x380 kernel/time/tick-sched.c:723
 __tick_nohz_idle_stop_tick kernel/time/tick-sched.c:940 [inline]
 tick_nohz_idle_stop_tick+0x3c2/0x670 kernel/time/tick-sched.c:970
 cpuidle_idle_call kernel/sched/idle.c:151 [inline]
 do_idle+0x1e0/0x2c0 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 start_secondary+0x207/0x260 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/14 20:02 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/14 11:25 https://github.com/google/ktsan.git kcsan d724f94f63de a6aef847 .config console log report ci2-upstream-kcsan-gce
2019/10/14 01:12 https://github.com/google/ktsan.git kcsan d724f94f63de 2f661ec4 .config console log report ci2-upstream-kcsan-gce
2019/10/12 13:52 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/12 10:45 https://github.com/google/ktsan.git kcsan d724f94f63de 426631dd .config console log report ci2-upstream-kcsan-gce
2019/10/10 12:29 https://github.com/google/ktsan.git kcsan d724f94f63de d52eff28 .config console log report ci2-upstream-kcsan-gce
2019/10/08 08:59 https://github.com/google/ktsan.git kcsan c1c7521f03c7 28ac6e64 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.