[v6.1] INFO: rcu detected stall in sys_close (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fdb6fcb41cc7 Linux 6.1.176
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16bc3641580000
kernel config: https://syzkaller.appspot.com/x/.config?x=acfbe65fbce84c0c
dashboard link: https://syzkaller.appspot.com/bug?extid=8d76ca4f73bf1c160804
compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8a12ae1ddcea/disk-fdb6fcb4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d0dd1b27df77/vmlinux-fdb6fcb4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/871bf60ea1f2/bzImage-fdb6fcb4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8d76ca...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2685 jiffies s: 26785 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: 11646 Comm: syz.0.2206 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:__perf_event_output kernel/events/core.c:7732 [inline]
RIP: 0010:perf_event_output_forward+0x19f/0x2f0 kernel/events/core.c:7750
Code: ba 38 00 00 00 4c 89 f7 31 f6 e8 2c 8c 2e 00 4c 89 ef 4c 89 e6 4c 89 fa 48 8b 4c 24 10 e8 19 da ff ff 0f b7 8c 24 a6 00 00 00 <4c> 89 f7 4c 89 e6 4c 89 fa e8 e3 c3 03 00 4d 89 fd 4d 89 f7 41 89
RSP: 0018:ffffc900000073e0 EFLAGS: 00000046
RAX: d8f99cd1f73b5800 RBX: 1ffff92000000e80 RCX: 0000000000000128
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900000074f0 R08: ffffffff8e200f6f R09: 1ffffffff1c401ed
R10: dffffc0000000000 R11: fffffbfff1c401ee R12: ffffc900000076c0
R13: ffffc90000007480 R14: ffffc90000007420 R15: ffff888086ad7200
FS: 00007f6f2ba6e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 0000000075b3d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
__perf_event_overflow+0x457/0x630 kernel/events/core.c:9496
perf_swevent_overflow kernel/events/core.c:9579 [inline]
perf_swevent_event+0x315/0x570 kernel/events/core.c:9630
perf_tp_event+0x36b/0xc10 kernel/events/core.c:10064
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 e2 82 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: d8f99cd1f73b5800 RBX: 1ffff92000000f64 RCX: d8f99cd1f73b5800
RDX: dffffc0000000000 RSI: ffffffff8a8c17a0 RDI: ffffffff8adee1a0
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:preempt_count_sub+0xed/0x160 kernel/sched/core.c:5738
Code: 85 c7 0c 00 75 98 48 c7 c7 60 a7 8b 8a 48 c7 c6 40 a8 8b 8a e8 74 f9 f4 ff 0f 0b eb 81 48 c7 c1 40 91 bf 96 80 e1 07 80 c1 03 <38> c1 0f 8c 2e ff ff ff 89 fd 48 c7 c7 40 91 bf 96 e8 7d 89 7a 00
RSP: 0018:ffffc900032e7988 EFLAGS: 00000206
RAX: 0000000000000004 RBX: dffffc0000000000 RCX: ffffffff96bf9103
RDX: ffffc900032e7a01 RSI: dffffc0000000000 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffffc900032e7f10 R09: ffffc900032e7a98
R10: dffffc0000000000 R11: fffff5200065cf55 R12: ffffc900032e0000
R13: dffffc0000000000 R14: ffffc900032e7a58 R15: ffffc900032e7f20
unwind_next_frame+0x1719/0x1fd0 arch/x86/kernel/unwind_orc.c:629
arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
task_work_add+0x7f/0x330 kernel/task_work.c:48
fput+0xd9/0x1a0 fs/file_table.c:376
filp_close+0x108/0x150 fs/open.c:1439
__do_sys_close fs/open.c:1452 [inline]
__se_sys_close fs/open.c:1450 [inline]
__x64_sys_close+0x34/0x70 fs/open.c:1450
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: 0033:0x7f6f2ab9ce59
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:00007f6f2ba6e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007f6f2ae15fa0 RCX: 00007f6f2ab9ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f6f2ac32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6f2ae16038 R14: 00007f6f2ae15fa0 R15: 00007ffc6ef0cec8
</TASK>


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