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INFO: rcu detected stall in security_file_free (7)

Status: auto-obsoleted due to no activity on 2026/02/06 10:57
Subsystems: lsm
[Documentation on labels]
First crash: 112d, last: 98d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in security_file_free (2) kernel 1 C error error 2 1678d 1985d 0/29 closed as invalid on 2022/02/08 10:38
upstream INFO: rcu detected stall in security_file_free (5) bpf 1 1 478d 478d 0/29 auto-obsoleted due to no activity on 2025/01/22 11:32
upstream INFO: rcu detected stall in security_file_free (6) bpf 1 1 343d 343d 0/29 auto-obsoleted due to no activity on 2025/06/06 23:37
upstream INFO: rcu detected stall in security_file_free (3) lsm 1 1 775d 775d 0/29 auto-obsoleted due to no activity on 2024/04/01 03:51
upstream INFO: rcu detected stall in security_file_free mm 1 2 2230d 2265d 0/29 closed as dup on 2019/12/03 08:34
upstream INFO: rcu detected stall in security_file_free (4) lsm 1 1 604d 604d 0/29 auto-obsoleted due to no activity on 2024/09/19 05:43

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5811/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=35433, q=400 ncpus=2)
task:syz-executor    state:R  running task     stack:22872 pid:5811  tgid:5811  ppid:5806   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7256
 irqentry_exit+0x36/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: 94 08 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 12 21 e9 0e 0f 82 74 02 00 00 8b 35 8a 51 e9 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 29 94 08 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc900030378f8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c4760 RCX: 00000000ef9d33e4
RDX: 0000000000000000 RSI: ffffffff8da05d1b RDI: ffffffff8bf07040
RBP: 0000000000000002 R08: 0ac0d5affe09d4ff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2539 [inline]
 slab_free mm/slub.c:6634 [inline]
 kmem_cache_free+0x2d4/0x6c0 mm/slub.c:6744
 security_file_free+0xb9/0x180 security/security.c:2963
 file_free fs/file_table.c:71 [inline]
 __fput+0x556/0xb70 fs/file_table.c:481
 fput_close_sync+0x118/0x210 fs/file_table.c:573
 __do_sys_close fs/open.c:1589 [inline]
 __se_sys_close fs/open.c:1574 [inline]
 __x64_sys_close+0x8b/0x120 fs/open.c:1574
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3a8df8ee27
RSP: 002b:00007ffd597c0028 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f3a8df8ee27
RDX: fffffffffffff000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f3a8e011d7d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000202 R12: 00007ffd597c1170
R13: 00007f3a8e011d7d R14: 000000000005c2de R15: 00007ffd597c11b0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10536 jiffies! g35433 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=22162
rcu: rcu_preempt kthread starved for 10537 jiffies! g35433 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:28136 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1190/0x5de0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:7026
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 1297 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 36 8a 35 f6 48 89 df e8 1e de 35 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 45 e6 25 f6 65 8b 05 7e 25 3e 08 85 c0 74 16 5b
RSP: 0000:ffffc9000453f968 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff9add9280 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8da2b6dd RDI: ffffffff8bf07040
RBP: 0000000000000293 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90820cd7 R11: 0000000000000001 R12: ffffffff9add9388
R13: 0000000000000003 R14: 0000000000000001 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff888124b08000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000002c5030 CR3: 000000005b66b000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline]
 uart_port_unlock_deref drivers/tty/serial/serial_core.c:91 [inline]
 uart_port_unlock_deref drivers/tty/serial/serial_core.c:88 [inline]
 uart_write+0x4c1/0xb30 drivers/tty/serial/serial_core.c:626
 handle_tx+0x204/0x630 drivers/net/caif/caif_serial.c:222
 __netdev_start_xmit include/linux/netdevice.h:5248 [inline]
 netdev_start_xmit include/linux/netdevice.h:5257 [inline]
 xmit_one net/core/dev.c:3845 [inline]
 dev_hard_start_xmit+0x97/0x740 net/core/dev.c:3861
 __dev_queue_xmit+0xa46/0x4490 net/core/dev.c:4763
 dev_queue_xmit include/linux/netdevice.h:3365 [inline]
 tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62
 kthread+0x1e4/0x3e0 drivers/block/aoe/aoecmd.c:1241
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/08 10:49 upstream 38a2c275c3d3 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in security_file_free
2025/10/25 11:09 upstream 566771afc7a8 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in security_file_free
* Struck through repros no longer work on HEAD.