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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: 588d, last: 6d05h
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 Error
bd2a2e11-dffb-4c51-a8b1-050aaabef91d 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 6b4a844333e83556da95d61d7f207e7ef5cd4bc6
364f9a6e-8e04-4d4e-9761-d93a6610c0f5 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 6ccb967e465e832a7bfd7a116ad00d52a0923a5d failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: 21% (20162/92183) Updating files: 22% (20281/92183) Updating files: 23% (21203/92183) Updating files: 24% (22124/92183) Updating files: 25% (23046/92183) Updating files: 26% (23968/92183) Updating files: 27% (24890/92183) Updating files: 28% (25812/92183) Updating files: 29% (26734/92183) Updating files: 30% (27655/92183) Updating files: 31% (28577/92183) Updating files: 31% (29358/92183) Updating files: 32% (29499/92183) Updating files: 33% (30421/92183) Updating files: 34% (31343/92183) Updating files: 35% (32265/92183) error: unable to write file drivers/clk/samsung/clk-exynos5433.c error: unable to write file drivers/clk/samsung/clk-exynos7.c error: unable to write file drivers/clk/samsung/clk-exynos7870.c error: unable to write file drivers/clk/samsung/clk-exynos7885.c error: unable to write file drivers/clk/samsung/clk-exynos850.c error: unable to write file drivers/clk/samsung/clk-exynos8895.c error: unable to write file drivers/clk/samsung/clk-exynos990.c error: unable to write file drivers/clk/samsung/clk-exynosautov9.c error: unable to write file drivers/clk/samsung/clk-exynosautov920.c error: unable to write file drivers/clk/samsung/clk-fsd.c error: unable to write file drivers/clk/samsung/clk-gs101.c error: unable to write file drivers/clk/samsung/clk-pll.c error: unable to write file drivers/clk/samsung/clk-pll.h error: unable to write file drivers/clk/samsung/clk-s3c64xx.c error: unable to write file drivers/clk/samsung/clk-s5pv210-audss.c error: unable to write file drivers/clk/samsung/clk-s5pv210.c error: unable to write file drivers/clk/samsung/clk.c error: unable to write file drivers/clk/samsung/clk.h fatal: cannot create directory at 'drivers/clk/sifive': No space left on device
▶ ▼ 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 2337d 2338d 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 C inconclusive 6 16d 273d 0/3 upstream: reported C repro on 2025/09/02 23:57
upstream INFO: rcu detected stall in schedule_timeout (2) kernel 1 2 2338d 2338d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in schedule_timeout (4) kernel 1 1 1043d 1043d 0/29 closed as invalid on 2023/09/01 06:44
linux-6.1 INFO: rcu detected stall in schedule_timeout 1 28 711d 776d 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 948d 983d 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 2372d 2374d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in schedule_timeout (6) usb 1 C done 40 590d 747d 28/29 fixed on 2024/10/22 11:57
linux-5.15 INFO: rcu detected stall in schedule_timeout origin:upstream 1 C inconclusive 13 36d 741d 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 C error 5 138d 210d 0/2 upstream: reported C repro on 2025/11/04 19:17
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/04/12 15:44 27m retest repro linux-next error
2026/04/12 15:43 20m retest repro linux-next report log
2026/03/29 11:54 42m retest repro linux-next report log
2026/03/29 11:54 23m retest repro linux-next report log
2026/03/29 00:47 22m retest repro upstream report log
2026/01/18 10:05 51m retest repro linux-next error
2026/01/18 10:05 59m retest repro linux-next error
2026/01/18 10:05 1h04m retest repro linux-next report log
2026/01/17 23:34 1h28m retest repro net-next OK log
2026/01/17 22:37 52m retest repro upstream report log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=10913, q=267 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294957078-4294946575), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10504 jiffies! g10913 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:28840 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1295/0x67a0 kernel/sched/core.c:7189
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x205/0x7e0 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:100
Code: 40 df b2 8b 4c 89 74 24 70 48 c7 c6 70 ed f4 81 48 01 c3 e8 9b 64 66 f6 4c 89 e7 48 89 5c 24 30 e8 ce 7f 66 f6 e8 39 65 fe ff <4c> 89 e7 e8 11 31 66 f6 4c 89 e7 e8 99 20 66 f6 48 b8 00 00 00 00
RSP: 0018:ffffc90000157bb0 EFLAGS: 00010246
RAX: 0000000000208040 RBX: 00000000ffffaf10 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8c1c3980 RDI: 0000000000000001
RBP: 1ffff9200002af76 R08: 0000000000000000 R09: fffffbfff21af9ca
R10: ffffffff90d7ce57 R11: 0000000000000000 R12: ffffc90000157bd0
R13: 1ffffffff1c81e50 R14: ffff88801e2b0000 R15: dffffc0000000000
 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 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:
CPU: 1 UID: 0 PID: 5631 Comm: syz-executor184 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 56 61 5c 00 48 89 df 5b e9 1d ec 61 00 be 03 00 00 00 5b e9 72 e0 f0 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 65 8b 05 25 81 02 12 48 8b 34 24 65 48 8b 15 01 81 02
RSP: 0018:ffffc9000207f988 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f27d6e5cb28 RCX: ffffffff81fadf1e
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888079bd4a00
RBP: 0000000000000002 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc9000207fb90 R15: 0000000000000000
FS:  00007f27d6d846c0(0000) GS:ffff88812446d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffccf0fee80 CR3: 0000000070d82000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 get_futex_key+0x1ec/0x1510 kernel/futex/core.c:581
 futex_wait_setup+0x83/0x510 kernel/futex/waitwake.c:618
 __futex_wait+0x19f/0x300 kernel/futex/waitwake.c:686
 futex_wait+0xe6/0x370 kernel/futex/waitwake.c:719
 do_futex+0x1ef/0x350 kernel/futex/syscalls.c:130
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex kernel/futex/syscalls.c:188 [inline]
 __x64_sys_futex+0x34f/0x4d0 kernel/futex/syscalls.c:188
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f27d6dad4d9
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f27d6d84138 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f27d6e5cb28 RCX: 00007f27d6dad4d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f27d6e5cb28
RBP: 00007f27d6e5cb20 R08: 00007f27d6d84cdc R09: 00007f27d6d84cdc
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f27d6e5cb2c
R13: 0000000000000000 R14: 00007ffccf0ff9a0 R15: 00007ffccf0ffa88
 </TASK>

Crashes (43):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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
2026/05/19 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
2026/05/28 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
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.