INFO: rcu detected stall in chrdev

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	INFO: rcu detected stall in chrdev_open (6) mm usb	1				16	578d	845d	0/29	auto-obsoleted due to no activity on 2025/03/29 19:07
linux-6.1	INFO: rcu detected stall in chrdev_open	1				1	237d	237d	0/3	auto-obsoleted due to no activity on 2026/03/15 21:38
linux-5.15	INFO: rcu detected stall in chrdev_open	1				1	312d	312d	0/3	auto-obsoleted due to no activity on 2025/12/29 22:52
linux-4.14	INFO: rcu detected stall in chrdev_open	1	syz, C		error	4	1577d	1682d	0/1	upstream: reported C repro on 2021/12/21 07:54
linux-4.19	INFO: rcu detected stall in chrdev_open (3)	1	syz, C		error	17	1402d	1956d	0/1	upstream: reported C repro on 2021/03/22 19:09
upstream	INFO: rcu detected stall in chrdev_open (3) kernel	1				1	1341d	1341d	0/29	auto-obsoleted due to no activity on 2023/02/09 20:53
linux-6.1	INFO: rcu detected stall in chrdev_open (2)	1				2	33d	87d	0/3	upstream: reported on 2026/05/04 04:53
upstream	INFO: rcu detected stall in chrdev_open (5) serial	1				1	1013d	1013d	0/29	auto-obsoleted due to no activity on 2024/01/19 06:34
linux-4.19	INFO: rcu detected stall in chrdev_open	1				1	2400d	2400d	0/1	auto-closed as invalid on 2020/05/02 02:53
upstream	INFO: rcu detected stall in chrdev_open (4) media	1				1	1116d	1116d	0/29	auto-obsoleted due to no activity on 2023/10/08 11:46
upstream	INFO: rcu detected stall in chrdev_open (2) serial	1	syz, C	done	inconclusive	55	1654d	2421d	0/29	closed as invalid on 2022/02/08 10:45
upstream	INFO: rcu detected stall in chrdev_open mm	1				4	2430d	2431d	0/29	closed as invalid on 2019/12/04 14:04

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=31369, q=14) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294984069-4294973566), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.2 R running task 27184 15570 6719 0x00000000 Call Trace: <IRQ> sched_show_task kernel/sched/core.c:5338 [inline] sched_show_task.cold+0x2e2/0x343 kernel/sched/core.c:5313 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline] check_cpu_stall kernel/rcu/tree.c:1557 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0xaf0/0xddc kernel/rcu/tree.c:2682 update_process_times+0x2a/0x70 kernel/time/timer.c:1638 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1278 __run_hrtimer kernel/time/hrtimer.c:1401 [inline] __hrtimer_run_queues+0x2fc/0xd50 kernel/time/hrtimer.c:1463 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1521 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 </IRQ> RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:192 Code: c0 d8 56 d2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d b1 ac b0 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 66 13 25 fa 65 8b 05 8f 43 e0 78 85 c0 74 02 5d RSP: 0018:ffff888043d277c0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff11a4adb RBX: ffff88804fb2a660 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff88804fb2a8c4 RBP: ffff8880ae72c280 R08: ffff88804fb2a040 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88804fb2a040 R13: ffffffff878a5820 R14: ffff88804fb2a040 R15: ffff8880ae72c280 rq_unlock_irq kernel/sched/sched.h:1848 [inline] __schedule+0x1477/0x1d80 kernel/sched/core.c:3518 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 tty_open+0x729/0xb00 drivers/tty/tty_io.c:2036 chrdev_open+0x219/0x5c0 fs/char_dev.c:423 do_dentry_open+0x4a8/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x1031/0x4200 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3c0/0x500 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c829 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0a8477dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00000000004f8b60 RCX: 000000000045c829 RDX: 0000000000000000 RSI: 0000000020000840 RDI: ffffffffffffff9c RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000007fe R14: 00000000004cabb1 R15: 00007f0a8477e6d4 rcu: rcu_preempt kthread starved for 10540 jiffies! g31369 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29136 10 2 0x80000000 Call Trace: