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INFO: rcu detected stall in mrp_periodic_timer

Status: upstream: reported on 2026/06/17 00:42
Reported-by: syzbot+1299c3b55f233016e106@syzkaller.appspotmail.com
First crash: 1d20h, last: 1d20h
▶ ▼ Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: rcu detected stall in mrp_periodic_timer 1 2 2297d 2335d 0/1 auto-closed as invalid on 2020/07/01 22:48
upstream INFO: rcu detected stall in mrp_periodic_timer (4) kernel 1 1 1238d 1238d 0/29 auto-obsoleted due to no activity on 2023/04/26 22:06
upstream INFO: rcu detected stall in mrp_periodic_timer (2) net 1 1 2123d 2123d 0/29 auto-closed as invalid on 2020/11/23 04:34
upstream INFO: rcu detected stall in mrp_periodic_timer (5) net 1 2 689d 745d 0/29 auto-obsoleted due to no activity on 2024/10/27 01:42
upstream INFO: rcu detected stall in mrp_periodic_timer net 1 1 2326d 2326d 0/29 auto-closed as invalid on 2020/05/04 02:54
linux-4.19 INFO: rcu detected stall in mrp_periodic_timer 1 3 2271d 2321d 0/1 auto-closed as invalid on 2020/07/28 00:22
upstream INFO: rcu detected stall in mrp_periodic_timer (3) perf 1 1 1625d 1625d 0/29 closed as invalid on 2022/02/08 10:10
linux-6.6 INFO: rcu detected stall in mrp_periodic_timer origin:lts-only 1 C error 1 53d 53d 0/2 upstream: reported C repro on 2026/04/26 04:59
linux-4.19 BUG: soft lockup in mrp_periodic_timer (2) 1 3 1476d 1533d 0/1 auto-obsoleted due to no activity on 2022/10/01 18:22
linux-4.19 BUG: soft lockup in mrp_periodic_timer 1 1 1663d 1663d 0/1 auto-closed as invalid on 2022/03/28 02:00

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10500 ticks this GP) idle=495/1/0x4000000000000000 softirq=12849/12849 fqs=4231 
	(t=10500 jiffies g=14489 q=1692)
NMI backtrace for cpu 0
CPU: 0 PID: 5528 Comm: syz.4.423 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ea/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b4/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 4f 9d 8b f7 65 8b 05 70 86 3b 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90000007a20 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 27d1e8d772b75700
RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: 0000000000000001
RBP: ffffc90000007aa8 R08: ffffffff901d81b7 R09: 1ffffffff203b036
R10: dffffc0000000000 R11: fffffbfff203b037 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff8880b90280c0 R15: 1ffff92000000f44
 __mod_timer+0x91e/0xd00 kernel/time/timer.c:1081
 mrp_periodic_timer_arm net/802/mrp.c:617 [inline]
 mrp_periodic_timer+0x1c5/0x200 net/802/mrp.c:629
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804
Code: be ff ff ff ff e8 4c ee 68 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 f6 59 72 08 e8 f1 e6 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 c9 09 fe ff 43 80 3c
RSP: 0018:ffffc900031ff228 EFLAGS: 00000286
RAX: 27d1e8d772b75700 RBX: ffff8880b903a340 RCX: 27d1e8d772b75700
RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: ffffffff8a7a09c0
RBP: 1ffff11017207613 R08: ffffffff901d80cf R09: 1ffffffff203b019
R10: dffffc0000000000 R11: fffffbfff203b01a R12: 1ffff110172075c1
R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000
 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921
 context_switch kernel/sched/core.c:5052 [inline]
 __schedule+0x11f7/0x43c0 kernel/sched/core.c:6395
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x84/0x290 mm/kasan/generic.c:189
Code: 49 c1 e9 03 4b 8d 1c 21 49 89 df 4d 29 df 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 41 80 3b 00 <0f> 85 86 01 00 00 49 ff c3 48 ff c3 75 ee e9 18 01 00 00 44 89 dd
RSP: 0018:ffffc900031ff610 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff815da814
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d8a06e8
RBP: ffffc900031ff750 R08: ffffffff8d8a06ef R09: 1ffffffff1b140dd
R10: dffffc0000000000 R11: fffffbfff1b140dd R12: dffffc0000000001
R13: dffffc0000000000 R14: 1ffffffff1b140dd R15: 0000000000000001
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0xa4/0x8a0 kernel/locking/lockdep.c:5634
 rcu_read_unlock include/linux/rcupdate.h:773 [inline]
 inet_twsk_purge+0x7a7/0x840 net/ipv4/inet_timewait_sock.c:309
 ops_exit_list net/core/net_namespace.c:177 [inline]
 setup_net+0x844/0xa10 net/core/net_namespace.c:365
 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503
 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
 copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178
 copy_process+0x1834/0x3e20 kernel/fork.c:2293
 kernel_clone+0x23f/0x990 kernel/fork.c:2679
 __do_sys_clone kernel/fork.c:2796 [inline]
 __se_sys_clone kernel/fork.c:2780 [inline]
 __x64_sys_clone+0x19a/0x210 kernel/fork.c:2780
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe47e436e59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe47c68ffd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fe47e6affa0 RCX: 00007fe47e436e59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040100000
RBP: 00007fe47e4ccd6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fe47e6b0038 R14: 00007fe47e6affa0 R15: 00007ffc94f6d168
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/17 00:41 linux-5.15.y dc027a595035 62cc6db3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in mrp_periodic_timer
* Struck through repros no longer work on HEAD.