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INFO: rcu detected stall in irqentry_exit (2)

Status: upstream: reported on 2025/09/16 14:07
Reported-by: syzbot+052866219c84faa6fcbe@syzkaller.appspotmail.com
First crash: 233d, last: 4d06h
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in irqentry_exit 1 1 628d 628d 0/3 auto-obsoleted due to no activity on 2024/11/25 13:22
linux-6.6 INFO: rcu detected stall in irqentry_exit origin:lts-only 1 C inconclusive 19 32d 256d 0/2 upstream: reported C repro on 2025/08/25 11:36
linux-6.1 INFO: rcu detected stall in irqentry_exit (2) origin:lts-only 1 syz error 1 178d 178d 0/3 upstream: reported syz repro on 2025/11/10 20:44
linux-5.15 INFO: rcu detected stall in irqentry_exit 1 1 696d 696d 0/3 auto-obsoleted due to no activity on 2024/09/18 22:14
upstream INFO: rcu detected stall in irqentry_exit (2) kernel 1 C 1 211d 211d 0/29 closed as invalid on 2026/01/13 17:54
upstream INFO: rcu detected stall in irqentry_exit kernel 1 syz inconclusive inconclusive 2 505d 501d 0/29 auto-obsoleted due to no activity on 2025/03/29 05:27

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-....: (104 ticks this GP) idle=5cd/1/0x4000000000000002 softirq=125447/125448 fqs=5241 
	(detected by 1, t=10502 jiffies, g=167517, q=2061)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9238 Comm: syz.9.7489 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:216
Code: 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14 16 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 3a <c3> 0f 1f 80 00 00 00 00 48 8b 04 24 65 48 8b 0d c4 3a 89 7e 65 8b
RSP: 0018:ffffc90000007480 EFLAGS: 00000046
RAX: ffffffff818518e4 RBX: ffff8880b903b1f0 RCX: ffff888097c81dc0
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff8880b903b1f0
RBP: 0000000000000000 R08: ffff8880b903b1ff R09: ffff8880b903b1f0
R10: dffffc0000000000 R11: ffffed1017207640 R12: ffff8880b903b208
R13: dffffc0000000000 R14: ffff8880b903b200 R15: 1ffff11017207641
FS:  00007f8b592546c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000aa57c000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 irq_work_queue_on+0x14/0x220 kernel/irq_work.c:89
 rcu_read_unlock_special+0x37b/0x4a0 kernel/rcu/tree_plugin.h:667
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __perf_event_output kernel/events/core.c:7813 [inline]
 perf_event_output_forward+0x255/0x2e0 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_swevent_overflow kernel/events/core.c:9591 [inline]
 perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
 perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: 00 00 00 66 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be 59 97 f7 48 89 df e8 f6 31 98 f7 e8 01 27 b9 f7 fb bf 01 00 00 00 <e8> d6 38 8c f7 65 8b 05 67 36 3c 76 85 c0 74 02 5b c3 e8 b4 43 3a
RSP: 0018:ffffc90000007c90 EFLAGS: 00000286
RAX: 5d0475dc8b49ec00 RBX: ffff8880b90280c0 RCX: 5d0475dc8b49ec00
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: 0000000000000001
RBP: ffffc90000007df0 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: ffff8880b90280c0
R13: 1ffff11017205020 R14: ffff8880b90372d0 R15: ffffc90000007d40
 expire_timers kernel/time/timer.c:1698 [inline]
 __run_timers+0x52f/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:refill_stock+0x344/0x540 mm/memcontrol.c:2283
Code: 00 00 9c 8f 44 24 60 f7 44 24 60 00 02 00 00 41 c6 44 1e 04 f8 75 46 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <49> c7 04 1e 00 00 00 00 41 c7 44 1e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc9000327f9c0 EFLAGS: 00000206
RAX: 5d0475dc8b49ec00 RBX: dffffc0000000000 RCX: 5d0475dc8b49ec00
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc9000327fab0 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 000000000000000f
R13: ffff8880b9036498 R14: 1ffff9200064ff40 R15: 0000000000000a02
 obj_cgroup_uncharge_pages mm/memcontrol.c:2996 [inline]
 __memcg_kmem_uncharge_page+0x87/0x140 mm/memcontrol.c:3083
 memcg_kmem_uncharge_page include/linux/memcontrol.h:1703 [inline]
 free_thread_stack+0x22e/0x430 kernel/fork.c:283
 release_task_stack kernel/fork.c:433 [inline]
 put_task_stack+0x97/0x140 kernel/fork.c:444
 finish_task_switch+0x26f/0x640 kernel/sched/core.c:4961
 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:__syscall_enter_from_user_work kernel/entry/common.c:93 [inline]
RIP: 0010:syscall_enter_from_user_mode+0x2a/0x70 kernel/entry/common.c:114
Code: 41 56 53 48 89 f3 49 89 fe 48 8b 7c 24 10 e8 3d f6 ff ff eb 31 eb 35 e8 74 8d c2 f7 e8 6f 8b c2 f7 fb 65 48 8b 05 d6 9a 45 76 <48> 8b 70 08 40 f6 c6 3f 74 0b 4c 89 f7 5b 41 5e e9 11 8b aa f7 48
RSP: 0018:ffffc9000327ff08 EFLAGS: 00000286
RAX: ffff888097c81dc0 RBX: 00000000000000ca RCX: 5d0475dc8b49ec00
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: ffffc9000327ff48 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc9000327ff58 R15: 0000000000000000
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8b5affadd9
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:00007f8b592540e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f8b5b273fa8 RCX: 00007f8b5affadd9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8b5b273fac
RBP: 00007f8b5b273fa0 R08: 001238e62ccdcf1a R09: 0000000000000000
R10: 0000000000000020 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8b5b274038 R14: 00007fffeaa99ea0 R15: 00007fffeaa99f88
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/04 05:39 linux-5.15.y ef251c45f1cd a0d91488 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
2026/03/05 05:55 linux-5.15.y 91d48252ad4b a9fe5c9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
2026/02/12 07:57 linux-5.15.y e45d5d41c134 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
2025/12/07 10:23 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
2025/11/15 09:16 linux-5.15.y cc5ec8769306 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
2025/10/13 18:16 linux-5.15.y 29e53a5b1c4f b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
2025/09/16 14:07 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in irqentry_exit
* Struck through repros no longer work on HEAD.