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INFO: rcu detected stall in security_file_open (3)

Status: upstream: reported on 2025/08/25 12:48
Reported-by: syzbot+d0ed163317f17bfd41ed@syzkaller.appspotmail.com
First crash: 180d, last: 14h20m
▶ ▼ Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in security_file_open (5) tomoyo 1 4 1550d 1660d 0/29 closed as invalid on 2022/02/08 09:50
upstream INFO: rcu detected stall in security_file_open (3) afs 1 C done done 2 1970d 1970d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in security_file_open mm 1 5 2271d 2272d 0/29 closed as invalid on 2019/12/04 14:04
linux-6.6 INFO: rcu detected stall in security_file_open origin:upstream 1 syz error 4 5d21h 91d 0/2 upstream: reported syz repro on 2025/11/22 02:38
upstream INFO: rcu detected stall in security_file_open (2) mm 1 2 2236d 2236d 0/29 closed as invalid on 2020/01/08 05:23
linux-6.1 INFO: rcu detected stall in security_file_open 1 1 885d 885d 0/3 auto-obsoleted due to no activity on 2023/12/28 22:15
linux-5.15 INFO: rcu detected stall in security_file_open (2) origin:upstream 1 syz error 6 1d11h 375d 0/3 upstream: reported syz repro on 2025/02/11 10:29
upstream INFO: rcu detected stall in security_file_open (4) tomoyo 1 1 1769d 1769d 0/29 auto-closed as invalid on 2021/06/18 10:54
linux-6.1 INFO: rcu detected stall in security_file_open (2) 1 1 542d 542d 0/3 auto-obsoleted due to no activity on 2024/12/06 07:18
linux-5.15 INFO: rcu detected stall in security_file_open 1 3 495d 581d 0/3 auto-obsoleted due to no activity on 2025/01/22 08:07
upstream INFO: rcu detected stall in security_file_open (6) tomoyo mm 1 C error 324 3d07h 970d 0/29 closed as dup on 2023/06/27 10:07

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2685 jiffies s: 6041 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6893 Comm: syz.1.902 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__kasan_check_write+0x0/0x10 mm/kasan/shadow.c:37
Code: 8c eb 0a 48 c7 c7 f7 57 45 8c 48 89 de e8 38 0b 4e 08 31 ed eb d7 00 00 cc cc 89 f6 48 8b 0c 24 31 d2 e9 a3 ec ff ff 0f 1f 00 <89> f6 48 8b 0c 24 ba 01 00 00 00 e9 90 ec ff ff 55 41 56 53 48 89
RSP: 0018:ffffc900000071d8 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880b8e340f8 RCX: ffff88802fcb3b80
RDX: 0000000000000100 RSI: 0000000000000008 RDI: ffff8880b8e340f8
RBP: ffffc90000007288 R08: ffff8880b8e3b9fb R09: 1ffff110171c773f
R10: dffffc0000000000 R11: ffffed10171c7740 R12: 1ffff92000000e40
R13: 0000000000000000 R14: 1ffff110171c773e R15: ffff8880b8e3b9f0
FS:  00007f40dadca6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f40dada9d58 CR3: 0000000027c52000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 instrument_atomic_write include/linux/instrumented.h:87 [inline]
 llist_add_batch+0xcb/0x180 lib/llist.c:33
 llist_add include/linux/llist.h:221 [inline]
 __irq_work_queue_local+0xad/0x190 kernel/irq_work.c:97
 irq_work_queue_on+0x13c/0x260 kernel/irq_work.c:165
 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 trace_call_bpf+0x5bb/0x6b0 kernel/trace/bpf_trace.c:137
 perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:9997
 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 92 31 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007760 EFLAGS: 00000206
RAX: 298c4dc063817900 RBX: 1ffff92000000ef4 RCX: 298c4dc063817900
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0de0
RBP: ffffc90000007860 R08: ffffffff90af5337 R09: 1ffffffff215ea66
R10: dffffc0000000000 R11: fffffbfff215ea67 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ndisc_send_skb+0xd9d/0x14e0 net/ipv6/ndisc.c:521
 addrconf_rs_timer+0x2d1/0x630 net/ipv6/addrconf.c:3979
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6874
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 f5 a2 23 f7 e8 20 98 53 f7 fb bf 01 00 00 00 <e8> 75 b9 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc9000d75f420 EFLAGS: 00000282
RAX: 298c4dc063817900 RBX: 0000000000000000 RCX: 298c4dc063817900
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: 0000000000000001
RBP: ffffc9000d75f4d0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001aebe84
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:tomoyo_check_path_acl+0x7c/0x1c0 security/tomoyo/file.c:258
Code: 00 41 0f b6 2f bf 20 00 00 00 89 ee e8 1d 0f b4 fd 83 fd 1f 0f 87 30 01 00 00 e8 af 0c b4 fd 41 bf 01 00 00 00 89 e9 41 d3 e7 <44> 89 fe 44 21 e6 31 ff e8 f7 0f b4 fd 45 21 e7 74 55 4c 8d 7b 18
RSP: 0018:ffffc9000d75f590 EFLAGS: 00000202
RAX: ffffffff83ce6871 RBX: ffffc9000d75f6e0 RCX: 0000000000000001
RDX: ffffc9000c6b9000 RSI: 000000000000f41b RDI: 000000000000f41c
RBP: 0000000000000001 R08: ffff88802fcb3b80 R09: 0000000000000002
R10: 000000000000005c R11: 0000000000000002 R12: 0000000000000004
R13: dffffc0000000000 R14: ffff88802d015d00 R15: 0000000000000002
 tomoyo_check_acl+0x139/0x3f0 security/tomoyo/domain.c:175
 tomoyo_path_permission+0x1b4/0x380 security/tomoyo/file.c:586
 tomoyo_check_open_permission+0x29b/0x440 security/tomoyo/file.c:777
 security_file_open+0x5e/0xa0 security/security.c:1681
 do_dentry_open+0x305/0x10d0 fs/open.c:869
 do_open fs/namei.c:3634 [inline]
 path_openat+0x2635/0x2ee0 fs/namei.c:3791
 do_filp_open+0x1f1/0x430 fs/namei.c:3818
 do_sys_openat2+0x150/0x4b0 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1347
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f40d9f9c629
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f40dadca028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f40da215fa0 RCX: 00007f40d9f9c629
RDX: 000000000000275a RSI: 00002000000001c0 RDI: ffffffffffffff9c
RBP: 00007f40da032b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f40da216038 R14: 00007f40da215fa0 R15: 00007ffda5d75178
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/21 03:04 linux-6.1.y 779f9571ac3e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in security_file_open
2025/12/14 19:27 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_open
2025/12/12 02:02 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_open
2025/11/09 07:02 linux-6.1.y f6e38ae624cf 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_open
2025/08/25 12:47 linux-6.1.y 0bc96de781b4 bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in security_file_open
* Struck through repros no longer work on HEAD.