INFO: rcu detected stall in kernfs_fop_write_iter

Status: auto-obsoleted due to no activity on 2024/11/10 20:48
Subsystems: fs sctp
[Documentation on labels]
First crash: 805d, last: 710d
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in kernfs_fop_write_iter (2) net mm 1 4 455d 615d 0/29 auto-obsoleted due to no activity on 2025/07/23 14:56
linux-6.1 INFO: rcu detected stall in kernfs_fop_write_iter (4) 1 2 136d 203d 0/3 auto-obsoleted due to no activity on 2026/06/17 16:43
linux-5.15 INFO: rcu detected stall in kernfs_fop_write_iter 1 1 633d 633d 0/3 auto-obsoleted due to no activity on 2025/02/05 10:26
upstream INFO: rcu detected stall in kernfs_fop_write_iter (3) prio:low net 1 syz error error 24 12d 197d 0/29 upstream: reported syz repro on 2026/01/07 17:45
linux-6.1 INFO: rcu detected stall in kernfs_fop_write_iter (2) 1 2 716d 814d 0/3 auto-obsoleted due to no activity on 2024/11/14 04:13
linux-6.1 INFO: rcu detected stall in kernfs_fop_write_iter (3) 1 1 316d 316d 0/3 auto-obsoleted due to no activity on 2025/12/19 09:23
linux-5.15 INFO: rcu detected stall in kernfs_fop_write_iter (2) 1 1 80d 80d 0/3 upstream: reported on 2026/05/04 00:10
linux-6.1 INFO: rcu detected stall in kernfs_fop_write_iter 1 1 1093d 1093d 0/3 auto-obsoleted due to no activity on 2023/11/03 22:13
android-6-1 BUG: soft lockup in kernfs_fop_write_iter 1 1 436d 436d 0/2 auto-obsoleted due to no activity on 2025/08/11 05:47

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7102/1:b..l P8926/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=32325, q=369 ncpus=2)
task:syz-executor    state:R  running task     stack:21728 pid:8926  tgid:8926  ppid:8925   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x658/0xa30 kernel/locking/lockdep.c:5784
Code: 3c 3b 00 74 08 4c 89 f7 e8 85 af 87 00 f6 84 24 91 00 00 00 02 75 77 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25
RSP: 0000:ffffc9000d2ef140 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92001a5de3a RCX: ffffc9000d2ef103
RDX: 0000000000000007 RSI: ffffffff8beae6e0 RDI: ffffffff8c3f9040
RBP: ffffc9000d2ef270 R08: ffffffff8ff6a22f R09: 1ffffffff1fed445
R10: dffffc0000000000 R11: fffffbfff1fed446 R12: 1ffff92001a5de34
R13: 0000000000000246 R14: ffffc9000d2ef1d0 R15: dffffc0000000000
 xa_get_mark+0x997/0xa50
 __devl_is_registered net/devlink/devl_internal.h:96 [inline]
 devlink_port_notify+0xca/0x5c0 net/devlink/port.c:556
 devlink_port_netdevice_event+0x3ca/0x4d0
 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
 call_netdevice_notifiers net/core/dev.c:2046 [inline]
 unregister_netdevice_many_notify+0x1593/0x1c40 net/core/dev.c:11363
 unregister_netdevice_many net/core/dev.c:11406 [inline]
 unregister_netdevice_queue+0x303/0x370 net/core/dev.c:11281
 unregister_netdevice include/linux/netdevice.h:3129 [inline]
 nsim_destroy+0x180/0x5c0 drivers/net/netdevsim/netdev.c:778
 __nsim_dev_port_del+0x14b/0x1b0 drivers/net/netdevsim/dev.c:1425
 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1437 [inline]
 nsim_dev_reload_destroy+0x28a/0x490 drivers/net/netdevsim/dev.c:1658
 nsim_drv_remove+0x58/0x160 drivers/net/netdevsim/dev.c:1673
 device_remove drivers/base/dd.c:566 [inline]
 __device_release_driver drivers/base/dd.c:1272 [inline]
 device_release_driver_internal+0x4a9/0x7c0 drivers/base/dd.c:1295
 bus_remove_device+0x34f/0x420 drivers/base/bus.c:574
 device_del+0x57a/0x9b0 drivers/base/core.c:3871
 device_unregister+0x20/0xc0 drivers/base/core.c:3912
 nsim_bus_dev_del drivers/net/netdevsim/bus.c:462 [inline]
 del_device_store+0x363/0x480 drivers/net/netdevsim/bus.c:226
 kernfs_fop_write_iter+0x3a1/0x500 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa72/0xc90 fs/read_write.c:590
 ksys_write+0x1a0/0x2c0 fs/read_write.c:643
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f28689784df
RSP: 002b:00007ffe116af7e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f28689784df
RDX: 0000000000000001 RSI: 00007ffe116af830 RDI: 0000000000000005
RBP: 00007f28689e895f R08: 0000000000000000 R09: 00007ffe116af637
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffe116af830 R14: 00007f2869644620 R15: 0000000000000003
 </TASK>
task:kworker/u8:21   state:R  running task     stack:23280 pid:7102  tgid:7102  ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 preempt_schedule_notrace+0x100/0x140 kernel/sched/core.c:6801
 preempt_schedule_notrace_thunk+0x1a/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x7e/0xb0 kernel/rcu/tree.c:727
 rcu_read_lock include/linux/rcupdate.h:839 [inline]
 batadv_nc_process_nc_paths+0xf3/0x3a0 net/batman-adv/network-coding.c:687
 batadv_nc_worker+0x42a/0x610 net/batman-adv/network-coding.c:728
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: rcu_preempt kthread starved for 10568 jiffies! g32325 f0x0 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:24464 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.11.0-rc3-syzkaller-00007-gd74da846046a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline]
RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 00 d7 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d e5 92 9b 00 f3 0f 1e fa fb f4 <fa> c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffc900001a7d08 EFLAGS: 00000246
RAX: ffff888017af0000 RBX: ffff88801d6a8064 RCX: 000000000190c131
RDX: 0000000000000001 RSI: ffff88801d6a8000 RDI: ffff88801d6a8064
RBP: 000000000003a678 R08: ffff8880b9337c7b R09: 1ffff11017266f8f
R10: dffffc0000000000 R11: ffffffff8badac90 R12: ffff88801b79a800
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8eecaa20
FS:  0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1d30693f98 CR3: 000000002d912000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:702
 cpuidle_enter_state+0x112/0x480 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:230 [inline]
 do_idle+0x375/0x5d0 kernel/sched/idle.c:326
 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424
 start_secondary+0x100/0x100 arch/x86/kernel/smpboot.c:313
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/12 20:39 upstream d74da846046a 7b0f4b46 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in kernfs_fop_write_iter
2024/08/02 01:14 upstream c0ecd6388360 1e9c4cf3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in kernfs_fop_write_iter
2024/07/22 17:15 upstream 933069701c1b f063dfd9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in kernfs_fop_write_iter
2024/07/02 20:23 upstream 1dfe225e9af5 8373af66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in kernfs_fop_write_iter
2024/05/19 09:28 upstream 0450d2083be6 c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in kernfs_fop_write_iter
2024/05/13 11:52 upstream a38297e3fb01 9026e142 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in kernfs_fop_write_iter
2024/05/09 13:07 upstream 45db3ab70092 20bf80e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in kernfs_fop_write_iter
* Struck through repros no longer work on HEAD.