INFO: rcu detected stall in schedule_timeout (7)

Status: upstream: reported C repro on 2024/11/09 08:24
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+8926d1b522e7194a4b3e@syzkaller.appspotmail.com
First crash: 732d, last: 1h45m
Cause bisection: failed (error log, bisect log)
  
Fix bisection: failed (error log, bisect log)
  
▶ ▼ ✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
bd2a2e11 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ INFO: rcu detected stall in schedule_timeout (7) 2026/05/31 02:56 2026/05/31 02:56 2026/05/31 03:53 6b4a8443
364f9a6e assessment-security 💥 INFO: rcu detected stall in schedule_timeout (7) 2026/05/14 13:44 2026/05/14 13:44 2026/05/14 13:45 6ccb967e
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] INFO: rcu detected stall in schedule_timeout (7) 0 (2) 2025/09/01 01:14
▶ ▼ Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in schedule_timeout (3) cgroups mm 1 11 2481d 2482d 0/29 closed as invalid on 2020/01/09 08:13
linux-6.1 INFO: rcu detected stall in schedule_timeout (2) origin:lts-only 1 syz, C inconclusive 9 25d 417d 0/3 upstream: reported C repro on 2025/09/02 23:57
upstream INFO: rcu detected stall in schedule_timeout (2) kernel 1 2 2482d 2482d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in schedule_timeout (4) kernel 1 1 1187d 1187d 0/29 closed as invalid on 2023/09/01 06:44
linux-6.1 INFO: rcu detected stall in schedule_timeout 1 28 855d 920d 0/3 auto-obsoleted due to no activity on 2024/08/31 04:44
upstream INFO: rcu detected stall in schedule_timeout (5) kernel 1 2 1092d 1127d 0/29 auto-obsoleted due to no activity on 2024/01/26 16:31
upstream INFO: rcu detected stall in schedule_timeout cgroups mm 1 69 2516d 2518d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in schedule_timeout (6) usb 1 syz, C done 40 734d 891d 28/29 fixed on 2024/10/22 11:57
linux-5.15 INFO: rcu detected stall in schedule_timeout origin:upstream 1 syz, C inconclusive 16 7d07h 885d 0/3 upstream: reported C repro on 2024/05/22 14:45
linux-6.6 INFO: rcu detected stall in schedule_timeout origin:upstream 1 syz, C error 14 20d 354d 0/2 upstream: reported C repro on 2025/11/04 19:17
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/09/20 11:08 0m retest repro linux-next error job log
2026/09/20 11:08 0m retest repro linux-next error job log
2026/09/20 11:08 0m retest repro upstream error job log
2026/09/20 11:08 0m retest repro upstream error job log
2026/09/20 11:08 0m retest repro linux-next error job log
2026/06/22 20:06 52m retest repro linux-next error
2026/06/11 05:01 30m retest repro upstream log
2026/06/11 05:01 29m retest repro upstream log
2026/06/11 05:01 27m retest repro linux-next log
2026/06/11 04:11 30m retest repro linux-next log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=13973, q=1023 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294967767-4294957265), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g13973 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->cpu=1
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:26120 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5583 [inline]
 __schedule+0x125e/0x6990 kernel/sched/core.c:7382
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:7662
 irqentry_exit_cond_resched arch/x86/include/asm/fred.h:105 [inline]
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:453 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:543 [inline]
 irqentry_exit+0x33f/0xab0 kernel/entry/common.c:154
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:37 [inline]
RIP: 0010:__timer_delete_sync+0x7d/0x1c0 kernel/time/timer.c:1611
Code: 4e f0 ff 4c 89 ee 48 89 df e8 5f 54 f0 ff 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 9d 45 15 00 58 48 85 db 0f 85 15 01 00 00 <e8> ee 4a 15 00 65 8b 1d 1f 78 bd 13 31 ff 81 e3 00 00 00 0f 89 de
RSP: 0018:ffffc90000157b88 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801fac8000 RSI: ffffffff81f8690c RDI: ffff88801fac8000
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90000157bd0
R13: ffffffff81f868d1 R14: ffff88801fac8000 R15: dffffc0000000000
 schedule_timeout+0x12f/0x280 kernel/time/sleep_timeout.c:100
 rcu_gp_fqs_loop+0x1a9/0x930 kernel/rcu/tree.c:2122
 rcu_gp_kthread+0x179/0x260 kernel/rcu/tree.c:2330
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6058 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x46/0x70 kernel/kcov.c:213
Code: 00 01 00 ff 74 1e f6 c4 01 74 44 a9 00 00 00 0f 75 3d f7 c1 00 00 00 f0 75 35 8b 82 44 17 00 00 85 c0 74 2b 8b 82 18 17 00 00 <83> f8 02 75 20 48 8b 8a 20 17 00 00 8b 92 1c 17 00 00 48 8b 01 48
RSP: 0018:ffffc900025d7b68 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880287b2580 RCX: 0000000000000000
RDX: ffff8880287b2580 RSI: ffffffff82640bf9 RDI: ffff8880287b2580
RBP: ffffffff8c082940 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000073
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffffffff000
FS:  00007f8f14aa46c0(0000) GS:ffff8881225c2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 000000003933b000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 __might_fault+0x79/0x140 mm/memory.c:7480
 __copy_from_user include/linux/uaccess.h:115 [inline]
 check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:36 [inline]
 fpu__restore_sig+0x23e/0xe20 arch/x86/kernel/fpu/signal.c:497
 restore_sigcontext+0x4cb/0x6a0 arch/x86/kernel/signal_64.c:95
 __do_sys_rt_sigreturn+0x19b/0x290 arch/x86/kernel/signal_64.c:266
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8f13b9f557
Code: 83 c8 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
RSP: 002b:00007f8f14aa40e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f8f13e25fa8 RCX: 00007f8f13b9f559
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8f13e25fa8
RBP: 00007f8f13e25fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8f13e26038 R14: 00007fff32f83f60 R15: 00007fff32f84048
 </TASK>

Crashes (62):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/24 03:27 upstream 734bef548a96 d566bfda .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/05/18 17:55 upstream 5200f5f493f7 55156e84 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2025/12/15 19:10 upstream 8f0b4cce4481 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2025/12/15 14:47 linux-next 4a5663c04bb6 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/12/06 12:28 linux-next 6987d58a9cbc d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/09/14 11:38 linux-next 590b221ed425 e2beed91 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/10/25 06:40 upstream 5b0764a53235 1d9ca40b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2026/10/22 07:59 upstream 9ba46df34488 4ba27f85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2026/10/06 16:50 upstream 2c3418fffa9d f7710056 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/10/03 14:46 upstream e767a4ea70a3 57bbd979 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/09/26 19:26 upstream 6812ce4e4379 a3c7249d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/09/20 22:48 upstream 518e5b794c06 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/09/02 09:57 upstream 89a312991dc6 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2026/08/11 22:43 upstream f5bbbfec59b4 37a258dd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/08/01 00:59 upstream 8ba098e6b6ff 7664cf44 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2026/07/21 11:10 upstream b95f03f04d47 7c5de9c3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/07/20 06:52 upstream 980ab36ae597 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2026/06/30 05:51 upstream dc59e4fea9d8 fff8d0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/05/19 07:19 upstream 4d3a2a466b8d 9f74d399 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/04/18 01:51 upstream 43cfbdda5af6 24ecfc1e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/02/26 04:33 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/02/07 12:48 upstream 2687c848e578 f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2026/01/03 19:36 upstream 805f9a061372 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2025/12/20 17:00 upstream dd9b004b7ff3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in schedule_timeout
2025/09/13 14:27 upstream 22f20375f5b7 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/08/30 00:03 upstream fb679c832b64 3e1beec6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/08/16 14:04 upstream dfd4b508c8c6 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/07/07 18:06 upstream d7b8f8e20813 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/05/05 11:26 upstream 92a09c47464d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/04/09 04:59 upstream bec7dcbc242c b133e63a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/03/05 16:23 upstream 48a5eed9ad58 60f5d8d9 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in schedule_timeout
2025/02/28 05:07 upstream 1e15510b71c9 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/02/21 12:54 upstream 27eddbf34490 0808a665 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/02/09 12:23 upstream 9946eaf552b1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in schedule_timeout
2025/02/06 06:41 upstream 92514ef226f5 577d049b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/01/20 19:45 upstream ffd294d346d1 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/01/17 21:40 upstream 9bffa1ad25b8 953d1c45 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/01/17 14:57 upstream 9bffa1ad25b8 953d1c45 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/01/07 05:57 upstream fbfd64d25c7a f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/01/02 14:55 upstream 56e6a3499e14 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2024/12/25 00:39 upstream 9b2ffa6148b1 444551c4 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2024/12/16 14:46 upstream 78d4f34e2115 f93b2b55 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2024/11/05 08:01 upstream 557329bcecc2 509da429 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2024/10/22 14:24 upstream c2ee9f594da8 9d74f456 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/10/22 08:28 upstream 552c50713f27 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in schedule_timeout
2025/05/05 00:01 upstream e8ab83e34bdc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in schedule_timeout
2026/07/25 05:23 net 78f75d632f74 05b26a28 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/07/12 04:15 net 3f1f75536668 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/10/21 03:53 net-next 6ac0d7ba21d5 df8746fb .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/07/23 01:22 net-next 24d0af194bcc 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/05/28 02:29 net-next 56ed77ff6022 4c36e7e5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/05/16 07:17 net-next 55834f0d7421 81fb92f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/09/08 13:35 net-next c6142e1913de d291dd2d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in schedule_timeout
2026/08/24 03:05 linux-next 903c1cf6dff9 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/12/23 07:40 linux-next cc3aa43b44bd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/09/23 06:33 linux-next 846bd2225ec3 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in schedule_timeout
2025/09/01 12:21 linux-next 7fa4d8dc380f 807a3b61 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/09/01 03:40 linux-next 7fa4d8dc380f 807a3b61 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/09/01 01:14 linux-next 7fa4d8dc380f 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2025/08/31 18:05 linux-next 7fa4d8dc380f 807a3b61 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in schedule_timeout
2024/10/26 16:52 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing c6d9e43954bf 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb INFO: rcu detected stall in schedule_timeout
* Struck through repros no longer work on HEAD.