INFO: rcu detected stall in sys_symlinkat

Status: auto-obsoleted due to no activity on 2023/09/03 15:54
Reported-by: syzbot+f9fd4ff8bb9a247bbd7e@syzkaller.appspotmail.com
First crash: 1157d, last: 1157d
▶ ▼ Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_symlinkat (3) ext4 1 3 1094d 1146d 0/29 auto-obsoleted due to no activity on 2023/10/26 22:46
linux-6.1 INFO: rcu detected stall in sys_symlinkat (3) origin:upstream 1 syz error 5 43d 449d 0/3 upstream: reported syz repro on 2025/05/03 06:00
linux-5.15 INFO: rcu detected stall in sys_symlinkat (3) 1 2 769d 794d 0/3 auto-obsoleted due to no activity on 2024/09/25 17:37
upstream INFO: rcu detected stall in sys_symlinkat (5) prio:normal tomoyo 1 syz error error 106 1d01h 599d 0/29 upstream: reported syz repro on 2024/12/04 02:45
linux-6.1 INFO: rcu detected stall in sys_symlinkat (2) 1 1 941d 941d 0/3 auto-obsoleted due to no activity on 2024/04/06 00:16
upstream INFO: rcu detected stall in sys_symlinkat kvm 1 5 1426d 1526d 0/29 auto-obsoleted due to no activity on 2022/11/28 07:06
linux-6.1 INFO: rcu detected stall in sys_symlinkat 1 1 1186d 1186d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:07
upstream INFO: rcu detected stall in sys_symlinkat (2) ext4 lsm 1 2 1239d 1333d 0/29 auto-obsoleted due to no activity on 2023/06/03 10:14
upstream INFO: rcu detected stall in sys_symlinkat (4) ext4 1 1 970d 970d 0/29 auto-obsoleted due to no activity on 2024/02/27 04:07
linux-5.15 INFO: rcu detected stall in sys_symlinkat (4) 1 2 185d 207d 0/3 auto-obsoleted due to no activity on 2026/05/02 14:14
linux-6.6 INFO: rcu detected stall in sys_symlinkat 1 1 148d 148d 0/2 auto-obsoleted due to no activity on 2026/06/08 11:28
linux-5.15 INFO: rcu detected stall in sys_symlinkat (2) 1 1 966d 966d 0/3 auto-obsoleted due to no activity on 2024/03/12 11:22
android-5-15 BUG: soft lockup in sys_symlinkat 1 13 741d 832d 0/2 auto-obsoleted due to no activity on 2024/10/13 01:26

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=dc3/1/0x4000000000000000 softirq=191010/191010 fqs=12 
	(detected by 0, t=10502 jiffies, g=339257, q=390)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 22877 Comm: syz-executor.5 Not tainted 5.15.113-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023
RIP: 0010:__lock_acquire+0xef7/0x1ff0
Code: e8 5e 65 c5 02 4c 89 f1 eb 8c 89 e8 25 ff 1f 00 00 c1 ed 03 81 e5 00 60 00 00 09 c5 4c 89 f8 48 c1 e8 20 29 c5 89 c1 c1 c1 04 <31> e9 44 01 f8 41 29 cf 89 ca c1 c2 06 44 31 fa 01 c1 29 d0 89 d6
RSP: 0018:ffffc90000dd0a00 EFLAGS: 00000016
RAX: 00000000c05882cd RBX: 0000000000000063 RCX: 0000000005882cdc
RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000
RBP: 000000003fa77d33 R08: dffffc0000000000 R09: fffffbfff1f79221
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff8880224b28a8 R14: 1ffff11004496514 R15: c05882cde8126320
FS:  0000555556bfb400(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f68908a6845 CR3: 0000000086352000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x61/0x3f0 lib/debugobjects.c:766
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481
 __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
 __hrtimer_run_queues+0x31d/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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:slab_pre_alloc_hook+0x1/0xc0 mm/slab.h:489
Code: c7 00 0a 9f 8c 48 89 ee e8 8c 5c 5f 02 e9 e7 fe ff ff e8 92 0b 38 ff eb 90 e8 2b 2d 52 08 66 2e 0f 1f 84 00 00 00 00 00 90 55 <41> 57 41 56 41 55 41 54 53 89 cd 49 89 d7 49 89 f6 49 89 fc 23 2d
RSP: 0018:ffffc90005037e50 EFLAGS: 00000286
RAX: 74f4cb8bd34ce300 RBX: 0000000000000000 RCX: 0000000000000cc0
RDX: 0000000000000001 RSI: ffffc90005037e60 RDI: ffff888011dc6500
RBP: 0000000000000000 R08: ffffffff81865a60 R09: fffffbfff1bc76ce
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888011dc6500
R13: 0000000000000000 R14: ffffffff81d70f08 R15: 0000000000000cc0
 slab_alloc_node mm/slub.c:3134 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x3f/0x280 mm/slub.c:3233
 getname_flags+0xb8/0x4e0 fs/namei.c:138
 getname fs/namei.c:217 [inline]
 __do_sys_symlinkat fs/namei.c:4404 [inline]
 __se_sys_symlinkat fs/namei.c:4401 [inline]
 __x64_sys_symlinkat+0x78/0xa0 fs/namei.c:4401
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f6890823aa7
Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0a 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd59e285d8 EFLAGS: 00000206 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6890823aa7
RDX: 00007f689087fd4d RSI: 00000000ffffff9c RDI: 00007ffd59e286a0
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffd59e28470
R10: 00007ffd59e28327 R11: 0000000000000206 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffd59e286a0
 </TASK>
rcu: rcu_preempt kthread starved for 10478 jiffies! g339257 f0x0 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:25080 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 22893 Comm: syz-executor.0 Not tainted 5.15.113-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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:481
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:586
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3888 [inline]
 rcu_sched_clock_irq+0x94f/0x1770 kernel/rcu/tree.c:2606
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:226 [inline]
 tick_sched_timer+0x22d/0x3c0 kernel/time/tick-sched.c:1430
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 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:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 0c b3 0b 00 41 83 e7 01 75 07 e8 a1 af 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc900052bf420 EFLAGS: 00000246
RAX: ffffffff817439d4 RBX: 1ffff11017367f19 RCX: 0000000000040000
RDX: ffffc900030b1000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc900052bf560 R08: ffffffff817439a4 R09: fffffbfff1f79221
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff8880b9b3f8c8 R14: ffff8880b9a3a700 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1183 [inline]
 text_poke_bp_batch+0x2ad/0x830 arch/x86/kernel/alternative.c:1374
 text_poke_flush arch/x86/kernel/alternative.c:1542 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1549
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:177
 static_key_enable+0x16/0x20 kernel/jump_label.c:190
 __sched_core_enable kernel/sched/core.c:307 [inline]
 sched_core_get+0x71/0x1d0 kernel/sched/core.c:331
 sched_core_alloc_cookie+0x71/0xa0 kernel/sched/core_sched.c:21
 sched_core_share_pid+0x30d/0x740 kernel/sched/core_sched.c:178
 __do_sys_prctl kernel/sys.c:2551 [inline]
 __se_sys_prctl+0x230/0x2ab0 kernel/sys.c:2285
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f68f818c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f68f66fe168 EFLAGS: 00000246 ORIG_RAX: 000000000000009d
RAX: ffffffffffffffda RBX: 00007f68f82abf80 RCX: 00007f68f818c169
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e
RBP: 00007f68f81e7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd6f89a82f R14: 00007f68f66fe300 R15: 0000000000022000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/26 15:54 linux-5.15.y 1fe619a7d252 b40ef614 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_symlinkat
* Struck through repros no longer work on HEAD.