syzbot

 sign-in | mailing list | source | docs
🐞 Open [1518]
≡ Subsystems
🐞 Fixed [6463]
🐞 Invalid [16364]
⬇ Missing Backports [199]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
💬 Send us feedback

INFO: rcu detected stall in sys_open (5)

Status: auto-obsoleted due to no activity on 2024/11/19 17:35
Subsystems: fs lsm
[Documentation on labels]
First crash: 426d, last: 338d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_open fs 1 1 2257d 2257d 0/29 auto-closed as invalid on 2019/10/25 09:11
linux-4.19 INFO: rcu detected stall in sys_open 1 1 2144d 2144d 0/1 auto-closed as invalid on 2020/01/09 20:01
linux-5.15 INFO: rcu detected stall in sys_open 1 9 284d 340d 0/3 auto-obsoleted due to no activity on 2025/01/23 05:49
upstream INFO: rcu detected stall in sys_open (3) fs 1 C inconclusive 5 1295d 1531d 0/29 closed as invalid on 2022/02/08 10:35
upstream INFO: rcu detected stall in sys_open (4) ext4 1 1 1187d 1187d 0/29 auto-closed as invalid on 2022/06/24 20:08
upstream INFO: rcu detected stall in sys_open (2) crypto 1 C done done 42 1719d 2069d 15/29 fixed on 2020/12/23 11:40
android-5-15 BUG: soft lockup in sys_open 1 1 444d 444d 0/2 auto-obsoleted due to no activity on 2024/08/06 04:14

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P15069/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=166905, q=169 ncpus=2)
task:syz-executor    state:S stack:24048 pid:15069 tgid:15069 ppid:15068  flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline]
RIP: 0010:read_seqbegin include/linux/seqlock.h:772 [inline]
RIP: 0010:read_seqbegin_or_lock_irqsave include/linux/seqlock.h:1133 [inline]
RIP: 0010:thread_group_cputime+0x184/0x820 kernel/sched/cputime.c:336
Code: 31 f6 4c 89 e7 e8 ec d0 04 00 48 8b b4 24 30 01 00 00 4c 89 e7 e8 5c c1 04 00 9c 58 f6 c4 02 5a 4c 8b 14 24 0f 85 bc 04 00 00 <4d> 8d 8a d8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ca 48 c1
RSP: 0018:ffffc90003b57920 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffc90003b57a70 RCX: 1ffffffff2025621
RDX: 0000000000000000 RSI: ffffffff8163b021 RDI: ffffffff8bb098c0
RBP: 1ffff9200076af33 R08: 0000000000000001 R09: 0000000000000001
R10: ffff88802a0af2c0 R11: 0000000000000000 R12: ffff88802a0af4a0
R13: ffff88807d8e9e00 R14: dffffc0000000000 R15: ffff88807d8ea360
 thread_group_cputime_adjusted+0x91/0x110 kernel/sched/cputime.c:639
 wait_task_zombie kernel/exit.c:1147 [inline]
 wait_consider_task+0x2289/0x4100 kernel/exit.c:1420
 do_wait_thread kernel/exit.c:1483 [inline]
 __do_wait+0x1e2/0x890 kernel/exit.c:1601
 do_wait+0x219/0x570 kernel/exit.c:1635
 kernel_wait4+0x16c/0x280 kernel/exit.c:1794
 __do_sys_wait4+0x15f/0x170 kernel/exit.c:1822
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdf55b700d7
RSP: 002b:00007ffef8c89090 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 0000000000000422 RCX: 00007fdf55b700d7
RDX: 0000000040000000 RSI: 00007ffef8c890ec RDI: 00000000ffffffff
RBP: 00007ffef8c890ec R08: 0000000000000000 R09: 00007fdf568fe080
R10: 0000000000000000 R11: 0000000000000293 R12: 00005555832c55eb
R13: 00005555832c5590 R14: 000000000017d520 R15: 00007ffef8c89140
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10481 jiffies! g166905 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=112522
rcu: rcu_preempt kthread starved for 10482 jiffies! g166905 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27680 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6621
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21400 Comm: syz.0.4869 Not tainted 6.11.0-rc4-syzkaller-00019-gb311c1b497e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline]
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline]
RIP: 0010:do_raw_spin_unlock+0x75/0x230 kernel/locking/spinlock_debug.c:141
Code: 48 89 df e8 dd c4 7e 00 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 6c 01 00 00 8b 03 85 c0 0f 84 f5 00 00 00 4c 8d 63 10
RSP: 0018:ffffc90000007d50 EFLAGS: 00000006
RAX: 0000000000000003 RBX: ffff8880615da2e8 RCX: ffffffff8168e7a3
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880615da2e8
RBP: ffff88804a458410 R08: 0000000000000000 R09: ffffed100c2bb45d
R10: ffff8880615da2eb R11: 0000000000000000 R12: 0000000000000002
R13: ffff88804a458400 R14: ffff8880615da340 R15: ffff88804a45a400
FS:  00007f1e543de6c0(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c356770 CR3: 000000005f5b6000 CR4: 00000000003506f0
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:142 [inline]
 _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x611/0xc60 net/sched/sch_taprio.c:981
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x20c/0xcc0 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x450 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:234
Code: 82 f8 15 00 00 83 f8 02 75 20 48 8b 8a 00 16 00 00 8b 92 fc 15 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 <c3> cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003d574a8 EFLAGS: 00000283
RAX: 0000000000001358 RBX: ffffc90003d57578 RCX: ffffc9001346d000
RDX: 0000000000040000 RSI: ffffffff813cdd20 RDI: 0000000000000005
RBP: ffffc90003d57900 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90003d57580
R13: ffffc90003d57588 R14: ffffc90003d50000 R15: 0000000000000001
 on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
 stack_access_ok+0xa0/0x270 arch/x86/kernel/unwind_orc.c:393
 deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
 unwind_next_frame+0x1b94/0x23a0 arch/x86/kernel/unwind_orc.c:648
 arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541
 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:3106
 dentry_free+0xc2/0x160 fs/dcache.c:383
 __dentry_kill+0x498/0x600 fs/dcache.c:629
 dput.part.0+0x4b1/0x9b0 fs/dcache.c:852
 dput+0x1f/0x30 fs/dcache.c:842
 handle_mounts fs/namei.c:1579 [inline]
 step_into+0x1199/0x2230 fs/namei.c:1877
 open_last_lookups fs/namei.c:3674 [inline]
 path_openat+0x44a/0x2d20 fs/namei.c:3883
 do_filp_open+0x1dc/0x430 fs/namei.c:3913
 do_sys_openat2+0x17a/0x1e0 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_open fs/open.c:1439 [inline]
 __se_sys_open fs/open.c:1435 [inline]
 __x64_sys_open+0x154/0x1e0 fs/open.c:1435
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e54979e79
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1e543de038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f1e54b16058 RCX: 00007f1e54979e79
RDX: 0000000000000054 RSI: 0000000000044200 RDI: 0000000020000780
RBP: 00007f1e549e7916 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1e54b16058 R15: 00007ffd19ca6be8
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/21 17:30 upstream b311c1b497e5 db5852f9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_open
2024/05/25 21:41 upstream 56fb6f92854f a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_open
2024/07/25 21:07 linux-next 864b1099d16f 32fcf98f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_open
* Struck through repros no longer work on HEAD.