INFO: rcu detected stall in security_file_open (4)

Status: upstream: reported on 2026/07/25 17:02
Reported-by: syzbot+1058a14501196131c417@syzkaller.appspotmail.com
First crash: 1d12h, last: 1d12h
▶ ▼ Similar bugs (12)
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 1705d 1815d 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 2126d 2125d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in security_file_open mm 1 5 2426d 2427d 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 5 96d 247d 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 2392d 2392d 0/29 closed as invalid on 2020/01/08 05:23
linux-6.1 INFO: rcu detected stall in security_file_open 1 1 1041d 1041d 0/3 auto-obsoleted due to no activity on 2023/12/28 22:15
linux-6.1 INFO: rcu detected stall in security_file_open (3) 1 6 144d 335d 0/3 auto-obsoleted due to no activity on 2026/06/12 23:26
linux-5.15 INFO: rcu detected stall in security_file_open (2) origin:upstream 1 syz error 10 100d 530d 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 1924d 1924d 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 697d 697d 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 650d 736d 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 432 2d15h 1125d 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-.... } 2686 jiffies s: 10197 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: 5386 Comm: syz.1.270 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:64
Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01
RSP: 0018:ffffc90000007638 EFLAGS: 00010002
RAX: ffffffff81a55a00 RBX: ffffc900000076c0 RCX: 0000000000000080
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffffc90000007740
RBP: ffffc900000078a8 R08: ffffc900000077bf R09: ffffc900000076c0
R10: dffffc0000000000 R11: fffff52000000ef8 R12: dffffc0000000000
R13: 0000000000000014 R14: ffffe8ffffc481f8 R15: ffffc90000007800
FS:  00007f5ae19d56c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000769f8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 perf_tp_event+0x195/0xc10 kernel/events/core.c:10041
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032
 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 a2 7c 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:ffffc90000007ae0 EFLAGS: 00000206
RAX: 7942b09cef53fd00 RBX: 1ffff92000000f64 RCX: 7942b09cef53fd00
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adf5de0
RBP: ffffc90000007bd0 R08: ffff8880b8e3580b R09: 1ffff110171c6b01
R10: dffffc0000000000 R11: ffffed10171c6b02 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3bb00 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x156/0x170 net/mac80211/util.c:826
 mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x522/0xc90 kernel/time/hrtimer.c:1815
 hrtimer_run_softirq+0x173/0x290 kernel/time/hrtimer.c:1832
 handle_softirqs+0x291/0x910 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:folio_entire_mapcount include/linux/mm.h:848 [inline]
RIP: 0010:compound_mapcount include/linux/mm.h:859 [inline]
RIP: 0010:free_tail_pages_check+0xbc/0x400 mm/page_alloc.c:1339
Code: 4c 89 ff be 08 00 00 00 e8 01 92 0a 00 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 5b 90 0a 00 49 f7 07 00 00 01 00 <0f> 84 8a 01 00 00 49 83 c7 54 4c 89 ff be 04 00 00 00 e8 cd 91 0a
RSP: 0018:ffffc9000490f2f0 EFLAGS: 00000206
RAX: 1ffffd40003e3580 RBX: ffffea0001f1ac40 RCX: ffffffff81c8d03f
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0001f1ac00
RBP: dffffc0000000000 R08: ffffea0001f1ac07 R09: 1ffffd40003e3580
R10: dffffc0000000000 R11: fffff940003e3581 R12: ffffea0001f1ac08
R13: dffffc0000000000 R14: ffffea0001f1ac00 R15: ffffea0001f1ac00
 free_pages_prepare mm/page_alloc.c:1467 [inline]
 free_pcp_prepare mm/page_alloc.c:1537 [inline]
 free_unref_page_prepare+0x602/0x9e0 mm/page_alloc.c:3414
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509
 free_slab mm/slub.c:2036 [inline]
 discard_slab mm/slub.c:2042 [inline]
 __unfreeze_partials+0x188/0x1e0 mm/slub.c:2591
 put_cpu_partial+0x17c/0x250 mm/slub.c:2667
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa3/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 tomoyo_realpath_from_path+0xe2/0x5c0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x212/0x440 security/tomoyo/file.c:771
 security_file_open+0x5e/0xa0 security/security.c:1682
 do_dentry_open+0x2fd/0x10b0 fs/open.c:869
 do_open fs/namei.c:3634 [inline]
 path_openat+0x2674/0x2f10 fs/namei.c:3791
 do_filp_open+0x1ee/0x420 fs/namei.c:3818
 do_sys_openat2+0x14b/0x4f0 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: 0033:0x7f5ae379de99
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:00007f5ae19d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f5ae3a26090 RCX: 00007f5ae379de99
RDX: 0000000000000000 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007f5ae3833eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ae3a26128 R14: 00007f5ae3a26090 R15: 00007ffe1d5fa178
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/25 17:02 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in security_file_open
* Struck through repros no longer work on HEAD.