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INFO: rcu detected stall in sys_chdir (3)

Status: auto-obsoleted due to no activity on 2025/02/25 02:15
Subsystems: bpf fs mm
[Documentation on labels]
First crash: 253d, last: 246d
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in chdir 1 1 13d 13d 0/3 upstream: reported on 2025/07/17 06:51
upstream INFO: rcu detected stall in sys_chdir (2) fs 1 2 366d 383d 0/29 auto-obsoleted due to no activity on 2024/10/27 21:52
upstream INFO: rcu detected stall in sys_chdir fs 1 1 887d 887d 0/29 auto-obsoleted due to no activity on 2023/05/26 02:40

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (3 ticks this GP) idle=37d4/1/0x4000000000000000 softirq=26348/26348 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=24897, q=387 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7595 Comm: syz-executor Not tainted 6.12.0-rc7-syzkaller-00138-g4262bacb748f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
RIP: 0010:lock_release+0x643/0xa30 kernel/locking/lockdep.c:5849
Code: c7 84 24 90 00 00 00 00 00 00 00 9c 8f 84 24 90 00 00 00 42 80 3c 3b 00 74 08 4c 89 f7 e8 e5 41 8e 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
RSP: 0018:ffffc90000a18b40 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffff9200014317a RCX: ffffc90000a18b03
RDX: 0000000000000000 RSI: ffffffff8c0adc40 RDI: ffffffff8c610ce0
RBP: ffffc90000a18c70 R08: ffffffff901d0cef R09: 1ffffffff203a19d
R10: dffffc0000000000 R11: fffffbfff203a19e R12: 1ffff92000143174
R13: 0000000000000046 R14: ffffc90000a18bd0 R15: dffffc0000000000
FS:  0000555560b0d500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7f220542a6 CR3: 00000000540e2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
 _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x9b4/0xca0 net/sched/sch_taprio.c:981
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_count_sub+0x6/0x170 kernel/sched/core.c:5818
Code: c7 c7 50 3f 1d 90 e8 59 86 9b 00 e9 66 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 56 <53> 89 fb 48 c7 c0 40 79 3d 9a 48 c1 e8 03 49 be 00 00 00 00 00 fc
RSP: 0018:ffffc9000f4dfd38 EFLAGS: 00000282
RAX: ffff888079c48000 RBX: ffff888079c48000 RCX: ffffffff9a3d7903
RDX: dffffc0000000000 RSI: ffffffff8c0acac0 RDI: 0000000000000001
RBP: ffff88801bafb780 R08: ffffffff901d0cef R09: 1ffffffff203a19d
R10: dffffc0000000000 R11: fffffbfff203a19e R12: 00000000ffffffff
R13: 0000000000000cc0 R14: 0000000000000001 R15: ffffffff82141b87
 __slab_alloc+0x65/0xa0 mm/slub.c:3910
 __slab_alloc_node mm/slub.c:3961 [inline]
 slab_alloc_node mm/slub.c:4122 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4141
 getname_flags+0xb7/0x540 fs/namei.c:139
 user_path_at+0x24/0x60 fs/namei.c:3015
 __do_sys_chdir fs/open.c:561 [inline]
 __se_sys_chdir+0xbc/0x220 fs/open.c:555
 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: 0033:0x7f7f2217d4d7
Code: ff ff 77 07 c3 66 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 b8 50 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc85326c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7f2217d4d7
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007ffc85326cb0
RBP: 00007ffc85326c9c R08: 0000000000000000 R09: 00007f7f22e6d6c0
R10: 0000555560b0d500 R11: 0000000000000246 R12: 0000000000000032
R13: 00000000000252f3 R14: 000000000002504e R15: 00007ffc85326cf0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g24897 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=9971
rcu: rcu_preempt kthread starved for 10502 jiffies! g24897 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25824 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x184f/0x4c30 kernel/sched/core.c:6693
 __schedule_loop kernel/sched/core.c:6770 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6785
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615
 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>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/19 12:50 net 4262bacb748f 571351cb .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in sys_chdir
2024/11/27 02:06 net-next fcc79e1714e8 52b38cc1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in sys_chdir
2024/11/20 14:19 linux-next ac24e26aa08f 4fca1650 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_chdir
* Struck through repros no longer work on HEAD.