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INFO: rcu detected stall in do_faccessat (7)

Status: auto-obsoleted due to no activity on 2025/04/10 08:15
Subsystems: fs
[Documentation on labels]
First crash: 273d, last: 273d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in do_faccessat (6) kernel 1 1 648d 648d 0/29 auto-obsoleted due to no activity on 2024/02/29 22:48
linux-5.15 INFO: rcu detected stall in do_faccessat 1 1 108d 108d 0/3 auto-obsoleted due to no activity on 2025/10/02 03:01
upstream INFO: rcu detected stall in do_faccessat (4) fs 1 1 1534d 1534d 0/29 auto-closed as invalid on 2021/09/26 22:47
upstream INFO: rcu detected stall in do_faccessat (2) fs 1 1 1851d 1851d 0/29 auto-closed as invalid on 2020/12/14 19:23
upstream INFO: rcu detected stall in do_faccessat (3) fs 1 1 1754d 1754d 0/29 auto-closed as invalid on 2021/03/21 19:47
upstream INFO: rcu detected stall in do_faccessat (5) fs 1 2 1431d 1452d 0/29 auto-closed as invalid on 2022/02/07 01:08
upstream INFO: rcu detected stall in do_faccessat fs 1 1 1949d 1949d 0/29 auto-closed as invalid on 2020/09/07 18:08

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P17281/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=59273, q=405 ncpus=2)
task:modprobe        state:R  running task     stack:22784 pid:17281 tgid:17281 ppid:11041  flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078
 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_acquire+0x264/0x550 kernel/locking/lockdep.c:5853
Code: 2b 00 74 08 4c 89 f7 e8 0a 9c 88 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900046b77a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920008d6f00 RCX: ffff88803336e4d8
RDX: dffffc0000000000 RSI: ffffffff8c0aaae0 RDI: ffffffff8c5edd60
RBP: ffffc900046b78e8 R08: ffffffff94271887 R09: 1ffffffff284e310
R10: dffffc0000000000 R11: fffffbfff284e311 R12: 1ffff920008d6efc
R13: dffffc0000000000 R14: ffffc900046b7800 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 dput+0x54/0x2b0 fs/dcache.c:860
 step_into+0x355/0x1080 fs/namei.c:1965
 walk_component fs/namei.c:2118 [inline]
 link_path_walk+0x7b7/0xea0 fs/namei.c:2477
 path_lookupat+0xa9/0x450 fs/namei.c:2633
 filename_lookup+0x2a3/0x670 fs/namei.c:2663
 user_path_at+0x3a/0x60 fs/namei.c:3070
 do_faccessat+0x5e2/0xb80 fs/open.c:485
 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: 0033:0x7f954a409c91
RSP: 002b:00007ffd2abe9158 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00007f954a32e4f8 RCX: 00007f954a409c91
RDX: 000000055dad2b44 RSI: 0000000000000000 RDI: 00007f954a32674b
RBP: 0000000000000000 R08: 0000000000000000 R09: 2b5587dcdab0d2ac
R10: 000000000000004f R11: 0000000000000246 R12: 0000000000000004
R13: 00007ffd2abe9238 R14: 00007ffd2abe9260 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10427 jiffies! g59273 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:26264 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 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: 6028 Comm: kworker/u8:14 Not tainted 6.13.0-rc6-syzkaller-00130-g2144da25584e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884
Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 56 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 e5 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 e4
RSP: 0018:ffffc9000ba676e0 EFLAGS: 00000293
RAX: ffffffff81938eeb RBX: 1ffff110170c8c65 RCX: ffff88801c79bc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000ba678e0 R08: ffffffff81938eba R09: 1ffffffff284e310
R10: dffffc0000000000 R11: fffffbfff284e311 R12: dffffc0000000000
R13: ffff8880b8646328 R14: ffff8880b873f940 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc832332bac CR3: 000000000e736000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2114 [inline]
 text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324
 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_disable_cpuslocked+0xd2/0x1c0 kernel/jump_label.c:240
 static_key_disable+0x1a/0x20 kernel/jump_label.c:248
 toggle_allocation_gate+0x1bf/0x260 mm/kfence/core.c:854
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 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>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/10 08:08 upstream 2144da25584e 67d7ec0a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in do_faccessat
* Struck through repros no longer work on HEAD.