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INFO: rcu detected stall in flock

Status: auto-obsoleted due to no activity on 2023/05/19 06:57
Subsystems: kernel
[Documentation on labels]
First crash: 925d, last: 925d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in flock (2) bpf 1 1 211d 211d 0/29 auto-obsoleted due to no activity on 2025/05/02 07:58

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-...D } 2690 jiffies s: 51957 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 19364 Comm: udevd Not tainted 6.2.0-rc8-syzkaller-00127-gdbeed98d89ea #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
RIP: 0010:check_preemption_disabled+0xa/0x170 lib/smp_processor_id.c:13
Code: 1f 44 00 00 0f 0b 0f 1f 44 00 00 5b e9 6f fb ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 56 41 55 49 89 f5 41 54 55 <48> 89 fd 53 0f 1f 44 00 00 65 44 8b 25 b1 ea f8 75 65 8b 1d a6 ea
RSP: 0018:ffffc900001e0d70 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8a4c4e60 RDI: ffffffff8aa6cc80
RBP: ffffffff8c7921e0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880792157c0
R13: ffffffff8a4c4e60 R14: 00000000ffffffff R15: ffff8880792161f8
FS:  00007f7736c91840(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe73d5a960 CR3: 000000001fd8a000 CR4: 0000000000350ee0
Call Trace:
 <IRQ>
 lockdep_recursion_finish kernel/locking/lockdep.c:466 [inline]
 lock_is_held_type+0xdb/0x140 kernel/locking/lockdep.c:5712
 lock_is_held include/linux/lockdep.h:283 [inline]
 rcu_read_lock_sched_held+0x3e/0x70 kernel/rcu/update.c:125
 trace_hrtimer_start include/trace/events/timer.h:198 [inline]
 debug_activate kernel/time/hrtimer.c:476 [inline]
 enqueue_hrtimer+0x328/0x470 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1702 [inline]
 __hrtimer_run_queues+0xc71/0xfb0 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x320/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline]
 __sysvec_apic_timer_interrupt+0x180/0x640 arch/x86/kernel/apic/apic.c:1113
 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:183 [inline]
RIP: 0010:unwind_next_frame+0x1c4/0x1d00 arch/x86/kernel/unwind_orc.c:467
Code: 00 00 00 81 49 c1 ef 08 41 8d 43 ff 41 39 c7 0f 83 e3 13 00 00 48 b8 00 00 00 00 00 fc ff df 44 89 fa 48 8d 3c 95 f4 57 a2 8f <48> 89 f9 48 c1 e9 03 0f b6 0c 01 48 89 f8 83 e0 07 83 c0 03 38 c8
RSP: 0018:ffffc9000377f710 EFLAGS: 00000287
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 1ffffffff2387740
RDX: 0000000000003856 RSI: 1ffff920006efefc RDI: ffffffff8fa3394c
RBP: ffffc9000377f818 R08: ffffffff8c606500 R09: ffffc9000377f7d0
R10: fffff520006eff05 R11: 0000000000094001 R12: ffffc9000377f805
R13: ffffc9000377f7d0 R14: ffffffff81385659 R15: 0000000000003856
 __unwind_start+0x51f/0x800 arch/x86/kernel/unwind_orc.c:736
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0x60/0xf0 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x90/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x82/0x90 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:761 [inline]
 slab_alloc_node mm/slub.c:3452 [inline]
 slab_alloc mm/slub.c:3460 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3467 [inline]
 kmem_cache_alloc+0x1e4/0x430 mm/slub.c:3476
 kmem_cache_zalloc include/linux/slab.h:710 [inline]
 locks_alloc_lock fs/locks.c:270 [inline]
 flock_lock_inode+0x16e/0xfe0 fs/locks.c:1023
 flock_lock_inode_wait+0xf5/0x230 fs/locks.c:2033
 locks_lock_inode_wait fs/locks.c:2060 [inline]
 locks_lock_file_wait include/linux/fs.h:1365 [inline]
 __do_sys_flock+0x498/0x510 fs/locks.c:2130
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f7736dace77
Code: eb 85 48 8b 15 02 f0 0c 00 f7 d8 64 89 02 b8 ff ff ff ff eb dd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 49 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d d1 ef 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe73d1d1a8 EFLAGS: 00000202 ORIG_RAX: 0000000000000049
RAX: ffffffffffffffda RBX: 000055ee94ae0d50 RCX: 00007f7736dace77
RDX: 00000000000a0800 RSI: 0000000000000005 RDI: 0000000000000008
RBP: 000055ee94ae0d50 R08: 00000000ffffffff R09: 00007ffe73d56080
R10: 0000000000000000 R11: 0000000000000202 R12: 000055ee94ae6ee0
R13: 000055ee94adf320 R14: 0000000000000008 R15: 000055ee94abb910
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/18 06:53 upstream dbeed98d89ea d02e9a70 .config console log report info ci-upstream-kasan-gce-root INFO: rcu detected stall in flock
* Struck through repros no longer work on HEAD.