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INFO: rcu detected stall in sys_openat

Status: upstream: reported C repro on 2023/06/19 20:52
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+a954abaa6fe5e4fd2e60@syzkaller.appspotmail.com
First crash: 449d, last: 4d04h
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2023/12/24 upstream (ToT) 861deac3b092 C [report] INFO: rcu detected stall in corrupted
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in sys_openat 3 369d 402d 0/3 auto-obsoleted due to no activity on 2023/12/16 21:24
upstream INFO: rcu detected stall in sys_openat exfat 5 2067d 2145d 0/27 closed as dup on 2018/10/27 13:02
linux-6.1 INFO: rcu detected stall in sys_openat (2) origin:upstream C 7 22d 181d 0/3 upstream: reported C repro on 2024/03/13 11:37
upstream INFO: rcu detected stall in sys_openat (3) mm kernfs C error 87 19h32m 373d 0/27 upstream: reported C repro on 2023/09/03 11:10
upstream INFO: rcu detected stall in sys_openat (2) kernfs 8 950d 1162d 0/27 closed as invalid on 2022/02/08 09:50
android-5-15 BUG: soft lockup in sys_openat (2) origin:lts C 5 22h17m 50d 0/2 upstream: reported C repro on 2024/07/22 19:41
android-5-15 BUG: soft lockup in sys_openat 21 101d 156d 0/2 auto-obsoleted due to no activity on 2024/07/21 23:03
▶ ▼ Fix bisection attempts (3)
Created Duration User Patch Repo Result
2024/04/21 19:24 1h43m bisect fix linux-5.15.y OK (0) job log log
2024/03/02 18:30 1h52m bisect fix linux-5.15.y OK (0) job log log
2024/01/23 07:09 1h10m bisect fix linux-5.15.y OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3534/1:b..l
	(detected by 0, t=10503 jiffies, g=3629, q=22)
task:syz-executor288 state:R  running task     stack:24984 pid: 3534 ppid:  3526 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 irqentry_exit+0x53/0x80 kernel/entry/common.c:426
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 dc 5c 67 00 f6 44 24 61 02 0f 85 84 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:ffffc90002ce7680 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200059cedc RCX: 1ffff9200059ce7c
RDX: dffffc0000000000 RSI: ffffffff8a8b2220 RDI: ffffffff8ad88080
RBP: ffffc90002ce77e0 R08: dffffc0000000000 R09: fffffbfff1f79e19
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200059ced8
R13: dffffc0000000000 R14: ffffc90002ce76e0 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
 rcu_read_lock include/linux/rcupdate.h:696 [inline]
 is_bpf_text_address+0x1d/0x260 kernel/bpf/core.c:721
 kernel_text_address kernel/extable.c:151 [inline]
 __kernel_text_address+0x94/0x100 kernel/extable.c:105
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 getname_flags+0xb8/0x4e0 fs/namei.c:138
 do_sys_openat2+0xd2/0x500 fs/open.c:1205
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_openat fs/open.c:1243 [inline]
 __se_sys_openat fs/open.c:1238 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1238
 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: 0033:0x7f9828cf0de0
RSP: 002b:00007ffeae9cd320 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007f9828cf0de0
RDX: 0000000000080001 RSI: 00007f9828d49180 RDI: 00000000ffffff9c
RBP: 00007f9828d49180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffeae9cd3c0
R13: 0000000000000002 R14: 00007ffeae9cd900 R15: 00007ffeae9cd8f0
 </TASK>
rcu: rcu_preempt kthread starved for 10545 jiffies! g3629 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:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 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: 3556 Comm: syz-executor288 Not tainted 5.15.145-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1788
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: d1 7e f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 2e 2a 3d f7 48 89 df e8 06 7e 3e f7 e8 51 28 61 f7 fb bf 01 00 00 00 <e8> 66 ba 31 f7 65 8b 05 d7 f5 dc 75 85 c0 74 02 5b c3 e8 64 0d db
RSP: 0018:ffffc90002d87bc0 EFLAGS: 00000282
RAX: 04f009d321ee4200 RBX: ffff888079354a00 RCX: ffffffff913c6f03
RDX: dffffc0000000000 RSI: ffffffff8a8b0f80 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff8186a260 R09: ffffed100f26a941
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021
R13: dffffc0000000000 R14: ffff888079354e98 R15: ffff888079354a00
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x13ee/0x14e0 kernel/signal.c:2892
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f9828cf1e79
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 18 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeae9cd888 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f9828cf1e79
RDX: 000000002006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000000f4240 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ffeae9cd900 R15: 00007ffeae9cd8f0
 </TASK>
sched: RT throttling activated

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/23 21:45 linux-5.15.y d93fa2c78854 fb427a07 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/09/07 03:48 linux-5.15.y 14e468424d3e 9750182a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/08/17 10:26 linux-5.15.y 7e89efd3ae1c dbc93b08 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/08/14 21:24 linux-5.15.y 7e89efd3ae1c e6b88e20 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/07/04 04:15 linux-5.15.y 4878aadf2d15 f76a75f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/06/06 12:38 linux-5.15.y c61bd26ae81a 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/05/18 06:30 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2024/04/26 01:01 linux-5.15.y c52b9710c83d 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_openat
2024/03/22 08:13 linux-5.15.y b95c01af2113 7a239ce7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2023/12/05 19:39 linux-5.15.y 9b91d36ba301 858d62d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2023/11/28 14:31 linux-5.15.y 2a910f4af54d 9fe51b7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2023/10/22 11:46 linux-5.15.y 00c03985402e 361b23dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sys_openat
2024/08/14 21:50 linux-5.15.y 7e89efd3ae1c e6b88e20 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in sys_openat
2024/07/05 15:49 linux-5.15.y f45bea23c39c 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in sys_openat
2023/10/28 08:20 linux-5.15.y 12952a23a5da 3c418d72 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in sys_openat
2023/08/26 11:34 linux-5.15.y f6f7927ac664 7ba13a15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
2023/06/19 20:51 linux-5.15.y 471e639e59d1 d521bc56 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_openat
* Struck through repros no longer work on HEAD.