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INFO: rcu detected stall in syscall_exit_to_user_mode

Status: upstream: reported C repro on 2023/08/26 22:23
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+82e2b3f11a49481f3ea3@syzkaller.appspotmail.com
First crash: 245d, last: 1d18h
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/09/08 upstream (ToT) 2ab35ce202f8 C [report] INFO: rcu detected stall in syscall_exit_to_user_mode
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in syscall_exit_to_user_mode cgroups mm 78 793d 974d 20/26 fixed on 2022/03/08 16:11
linux-6.1 INFO: rcu detected stall in syscall_exit_to_user_mode origin:upstream C 23 5d16h 387d 0/3 upstream: reported C repro on 2023/04/07 08:31
upstream INFO: rcu detected stall in syscall_exit_to_user_mode (2) usb C inconclusive 209 30m 509d 0/26 upstream: reported C repro on 2022/12/05 19:46
android-5-15 BUG: soft lockup in syscall_exit_to_user_mode 3 1d09h 9d02h 0/2 premoderation: reported on 2024/04/19 07:14

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=3585, q=29)
rcu: All QSes seen, last rcu_preempt kthread activity 10501 (4294954863-4294944362), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g3585 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3529 Comm: syz-executor229 Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
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: 91 80 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 be b4 3b f7 48 89 df e8 96 08 3d f7 e8 b1 bf 5f f7 fb bf 01 00 00 00 <e8> b6 44 30 f7 65 8b 05 87 52 db 75 85 c0 74 02 5b c3 e8 f4 70 d9
RSP: 0018:ffffc90002f57bc0 EFLAGS: 00000282
RAX: 660085fe3b30b800 RBX: ffff88807447ae40 RCX: ffffffff913edf03
RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff8186dd10 R09: ffffed100e88f5c9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021
R13: dffffc0000000000 R14: ffff88807447b2d8 R15: ffff88807447ae40
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x13ee/0x14e0 kernel/signal.c:2892
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f37459e8e79
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 18 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe45d76b18 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f37459e8e79
RDX: 000000002006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000000f4240 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000555555a95370
R13: 0000000000000004 R14: 00007ffe45d76b90 R15: 00007ffe45d76b80
 </TASK>

Crashes (55):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/25 21:12 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/25 01:49 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/21 22:44 linux-5.15.y c52b9710c83d af24b050 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/18 22:02 linux-5.15.y c52b9710c83d af24b050 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/16 11:49 linux-5.15.y fa3df276cd36 0d592ce4 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/15 02:35 linux-5.15.y fa3df276cd36 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/13 01:47 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/07 21:45 linux-5.15.y 9465fef4ae35 ca620dd8 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/03/25 08:48 linux-5.15.y b95c01af2113 0ea90952 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/03/21 17:11 linux-5.15.y b95c01af2113 6753db5c .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/03/02 12:17 linux-5.15.y 80efc6265290 25905f5d .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/02/25 23:41 linux-5.15.y 458ce51d0356 8d446f15 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/02/25 06:32 linux-5.15.y 458ce51d0356 8d446f15 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/02/11 19:44 linux-5.15.y 6139f2a02fe0 77b23aa1 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/02/11 05:29 linux-5.15.y 6139f2a02fe0 77b23aa1 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/01/05 00:57 linux-5.15.y d93fa2c78854 28c42cff .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/13 06:02 linux-5.15.y 8a1d809b0545 ebcad15c .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/09 15:04 linux-5.15.y 8a1d809b0545 28b24332 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/09 09:53 linux-5.15.y 8a1d809b0545 28b24332 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/04 13:13 linux-5.15.y 9b91d36ba301 f819d6f7 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/11/24 13:47 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/09/08 01:31 linux-5.15.y aff03380bda4 72324844 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/26 15:14 linux-5.15.y c52b9710c83d 059e9963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/26 12:53 linux-5.15.y c52b9710c83d 059e9963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/26 09:05 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/22 11:39 linux-5.15.y c52b9710c83d 36c961ad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/17 14:36 linux-5.15.y c52b9710c83d acc528cb .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/16 17:56 linux-5.15.y fa3df276cd36 18f6e127 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/13 00:02 linux-5.15.y cdfd0a7f0139 c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/04/09 02:01 linux-5.15.y 9465fef4ae35 f3234354 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/03/29 06:39 linux-5.15.y 9465fef4ae35 c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/03/02 19:54 linux-5.15.y 80efc6265290 25905f5d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/02/09 21:33 linux-5.15.y 6139f2a02fe0 77b23aa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/01/23 10:13 linux-5.15.y ddcaf4999061 1c0ecc51 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/01/23 08:50 linux-5.15.y ddcaf4999061 1c0ecc51 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/01/17 10:15 linux-5.15.y ddcaf4999061 c9a1c95b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/01/11 10:52 linux-5.15.y 26c690eff0a5 00f3cc59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2024/01/05 19:05 linux-5.15.y 26c690eff0a5 28c42cff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/17 12:33 linux-5.15.y d0fc081c6241 3222d10c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/12 16:02 linux-5.15.y 8a1d809b0545 ebcad15c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/12/03 15:55 linux-5.15.y 9b91d36ba301 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/11/11 12:16 linux-5.15.y 80529b4968a8 6d6dbf8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/11/08 18:33 linux-5.15.y 80529b4968a8 b93f63e8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/11/08 15:31 linux-5.15.y 12952a23a5da b93f63e8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/10/10 23:24 linux-5.15.y 02e21884dcf2 83165b57 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/10/09 20:24 linux-5.15.y 1edcec18cfb7 3c53c7d9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/10/06 02:24 linux-5.15.y b911329317b4 db17ad9f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/10/03 06:11 linux-5.15.y b911329317b4 65faba36 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/10/03 01:09 linux-5.15.y b911329317b4 65faba36 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/09/28 19:50 linux-5.15.y b911329317b4 d265efd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/09/13 09:40 linux-5.15.y aff03380bda4 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
2023/08/26 22:22 linux-5.15.y 5ddfe5cc8716 7ba13a15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in syscall_exit_to_user_mode
* Struck through repros no longer work on HEAD.