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INFO: rcu detected stall in security_file_free (6)

Status: auto-obsoleted due to no activity on 2025/06/06 23:37
Subsystems: bpf
[Documentation on labels]
First crash: 357d, last: 357d
▶ ▼ 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 1692d 1999d 0/29 closed as invalid on 2022/02/08 10:38
upstream INFO: rcu detected stall in security_file_free (7) lsm 1 2 113d 127d 0/29 auto-obsoleted due to no activity on 2026/02/06 10:57
upstream INFO: rcu detected stall in security_file_free (5) bpf 1 1 493d 493d 0/29 auto-obsoleted due to no activity on 2025/01/22 11:32
upstream INFO: rcu detected stall in security_file_free (3) lsm 1 1 789d 789d 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 2244d 2280d 0/29 closed as dup on 2019/12/03 08:34
upstream INFO: rcu detected stall in security_file_free (4) lsm 1 1 618d 618d 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: 	1-...!: (1 GPs behind) idle=7c54/1/0x4000000000000000 softirq=94939/94940 fqs=3
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P14462/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=75525, q=263 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 24496 Comm: syz.5.4192 Not tainted 6.14.0-rc5-syzkaller-00218-g2a520073e74f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:preempt_count_add+0x4e/0x150 kernel/sched/core.c:5860
Code: c0 03 65 01 3d 0b 8d 7b 7e 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 dd 00 00 00 8b 15 4d bc 03 19 85 d2 75 0b 65 8b 05 ea 8c 7b 7e <3c> f4 77 6b 65 8b 05 df 8c 7b 7e 25 ff ff ff 7f 39 c3 74 07 5b 5d
RSP: 0018:ffffc90000a28e08 EFLAGS: 00000046
RAX: 0000000000010001 RBX: 0000000000000001 RCX: 1ffffffff3518114
RDX: 0000000000000000 RSI: ffffffff81a70f96 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888059d1d340
R13: ffff8880b872c880 R14: ffff8880b872c680 R15: ffffffff896aae50
FS:  0000555561009500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3ad128 CR3: 000000003cb92000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:118 [inline]
 _raw_spin_lock_irq+0x1a/0x50 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1805 [inline]
 __hrtimer_run_queues+0x2be/0xae0 kernel/time/hrtimer.c:1865
 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/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:lock_release+0x3e5/0x6f0 kernel/locking/lockdep.c:5859
Code: 7e 83 f8 01 0f 85 fe 01 00 00 9c 58 f6 c4 02 0f 85 e9 01 00 00 48 f7 04 24 00 02 00 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 c7 43 08 00 00 00 00 48 8b 84 24 88
RSP: 0018:ffffc900047178c8 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff920008e2f1b RCX: ffffc90004717918
RDX: 1ffff11003e615e4 RSI: ffffffff8b6cfe00 RDI: ffffffff8bd36860
RBP: ffffffffffffffff R08: 0000000000000000 R09: fffffbfff20c4c42
R10: ffffffff90626217 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: ffff88801f30af28 R15: ffff88801f30a440
 rcu_lock_release include/linux/rcupdate.h:347 [inline]
 rcu_read_unlock include/linux/rcupdate.h:880 [inline]
 is_bpf_text_address+0x8f/0x1a0 kernel/bpf/core.c:774
 kernel_text_address kernel/extable.c:125 [inline]
 kernel_text_address+0x8d/0x100 kernel/extable.c:94
 __kernel_text_address+0xd/0x40 kernel/extable.c:79
 unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xa7/0x100 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4609 [inline]
 kmem_cache_free+0x2e2/0x4d0 mm/slub.c:4711
 security_file_free+0xb9/0x180 security/security.c:2894
 file_free fs/file_table.c:68 [inline]
 __fput+0x556/0xb70 fs/file_table.c:477
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f83ca18d169
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:00007ffc873b8478 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000019b2bb RCX: 00007f83ca18d169
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f83ca3a7ba0 R08: 0000000000000001 R09: 00000003873b876f
R10: 00007f83ca000000 R11: 0000000000000246 R12: 00007f83ca3a5fac
R13: 00007f83ca3a5fa0 R14: ffffffffffffffff R15: 00007ffc873b8590
 </TASK>
task:syz-executor    state:R  running task     stack:23888 pid:14462 tgid:14462 ppid:14431  task_flags:0x400140 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6944
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 copy_pte_range mm/memory.c:1201 [inline]
 copy_pmd_range mm/memory.c:1262 [inline]
 copy_pud_range mm/memory.c:1299 [inline]
 copy_p4d_range mm/memory.c:1323 [inline]
 copy_page_range+0x1e7f/0x5690 mm/memory.c:1421
 dup_mmap kernel/fork.c:748 [inline]
 dup_mm kernel/fork.c:1700 [inline]
 copy_mm kernel/fork.c:1752 [inline]
 copy_process+0x7ccb/0x8c50 kernel/fork.c:2403
 kernel_clone+0xfd/0x960 kernel/fork.c:2815
 __do_sys_clone+0xcf/0x120 kernel/fork.c:2958
 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: 0033:0x7fb25dd839d3
RSP: 002b:00007ffdd7c50c28 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb25dd839d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555906a97d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000019b296 R15: 00007ffdd7c50dc0
 </TASK>
rcu: rcu_preempt kthread starved for 10495 jiffies! g75525 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:27456 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0xf43/0x5890 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6857
 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 24504 Comm: modprobe Not tainted 6.14.0-rc5-syzkaller-00218-g2a520073e74f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x18/0x70 kernel/kcov.c:213
Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 15 94 f8 49 7e 65 8b 05 95 f8 49 7e a9 00 01 ff 00 <48> 8b 34 24 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0
RSP: 0018:ffffc90003e4fa38 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff8880b8744a80 RCX: ffffffff81add21a
RDX: ffff888028c64880 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffed10170e8951
R13: 0000000000000001 R14: ffff8880b863fe80 R15: ffff8880b8744a88
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05fb172440 CR3: 000000000df80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline]
 cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline]
 csd_lock_wait kernel/smp.c:340 [inline]
 smp_call_function_many_cond+0x4c4/0x12c0 kernel/smp.c:885
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:966 [inline]
 flush_tlb_mm_range+0x271/0x4a0 arch/x86/mm/tlb.c:1054
 tlb_flush arch/x86/include/asm/tlb.h:20 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:481 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:471 [inline]
 tlb_flush_mmu mm/mmu_gather.c:395 [inline]
 tlb_finish_mmu+0x3c9/0x7b0 mm/mmu_gather.c:488
 exit_mmap+0x40e/0xba0 mm/mmap.c:1297
 __mmput+0x12a/0x410 kernel/fork.c:1356
 mmput+0x62/0x70 kernel/fork.c:1378
 exit_mm kernel/exit.c:570 [inline]
 do_exit+0x9ba/0x2d70 kernel/exit.c:925
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096
 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 0033:0x7f05fb230a90
Code: Unable to access opcode bytes at 0x7f05fb230a66.
RSP: 002b:00007fff0e733e88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f05fb321860 RCX: 00007f05fb230a90
RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000001
RBP: 00007f05fb321860 R08: 0000000000000001 R09: 0d024e4c24cf512e
R10: 00007fff0e733d40 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f05fb325658 R15: 0000000000000001
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/08 23:34 upstream 2a520073e74f 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in security_file_free
* Struck through repros no longer work on HEAD.