[v5.15] INFO: rcu detected stall in __fput

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 91d48252ad4b Linux 5.15.202
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1588fbd6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=b1e9e345dd26e18ded1e
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15e95eba580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16b1b302580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1f63ca11335d/disk-91d48252.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/85d7c8824423/vmlinux-91d48252.xz
kernel image: https://storage.googleapis.com/syzbot-assets/11897ccd5b62/bzImage-91d48252.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b1e9e3...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-....: (1 ticks this GP) idle=6cf/1/0x4000000000000002 softirq=8053/8053 fqs=2100
(detected by 1, t=10503 jiffies, g=9885, q=214023)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4465 Comm: syz.1.60 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65
Code: 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 01 01
RSP: 0018:ffffc90000007458 EFLAGS: 00000002
RAX: ffffffff8197ff00 RBX: ffff8880503129c8 RCX: 0000000000000000
RDX: 0000000000000038 RSI: 0000000000000000 RDI: ffffc900000074d8
RBP: ffffc90000007578 R08: ffffc900000074d7 R09: ffffc900000074a0
R10: dffffc0000000000 R11: fffff52000000e9b R12: ffffc900000074a0
R13: 1ffff92000000e90 R14: ffffc90000007500 R15: ffffc900000076c0
FS: 000055557083f500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1f81140dac CR3: 000000005c27f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__perf_event_output kernel/events/core.c:7795 [inline]
perf_event_output_forward+0x172/0x2e0 kernel/events/core.c:7822
__perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
perf_swevent_overflow kernel/events/core.c:9591 [inline]
perf_swevent_event+0x4ad/0x530 kernel/events/core.c:9629
perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047
perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
perf_trace_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
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 12 f2 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: 86071fb5a7eca800 RBX: 1ffff92000000f64 RCX: 86071fb5a7eca800
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980
RBP: ffffc90000007bd8 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: ffffffff8c322f00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
rcu_read_unlock include/linux/rcupdate.h:772 [inline]
ieee80211_iterate_active_interfaces_atomic+0x132/0x140 net/mac80211/util.c:831
mac80211_hwsim_beacon+0x9b/0x180 drivers/net/wireless/mac80211_hwsim.c:1865
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x4f2/0xb70 kernel/time/hrtimer.c:1749
hrtimer_run_softirq+0x176/0x240 kernel/time/hrtimer.c:1766
handle_softirqs+0x339/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:kasan_quarantine_put+0x84/0x220 mm/kasan/quarantine.c:234
Code: e8 c1 18 c1 ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 0f 85 83 00 00 00 41 f7 c7 00 02 00 00 74 01 fb 31 c0 <48> 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f c3 48 8d 80 40 62 03 00 45
RSP: 0018:ffffc900031afd00 EFLAGS: 00000206
RAX: 86071fb5a7eca801 RBX: ffff888073a6eb60 RCX: 86071fb5a7eca800
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980
RBP: ffffc900031afd98 R08: ffff8880b903b30b R09: 1ffff11017207661
R10: dffffc0000000000 R11: ffffed1017207662 R12: ffff888016de9000
R13: ffff888073a6eb60 R14: 000000000007e890 R15: 0000000000000286
kasan_slab_free include/linux/kasan.h:230 [inline]
slab_free_hook mm/slub.c:1710 [inline]
slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736
slab_free mm/slub.c:3504 [inline]
kmem_cache_free+0x8f/0x210 mm/slub.c:3520
file_free fs/file_table.c:55 [inline]
__fput+0x627/0x930 fs/file_table.c:324
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f62144cb819
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:00007ffc3a09ea68 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f6214746da0 RCX: 00007f62144cb819
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f6214746da0 R08: 00007f6214745038 R09: 0000000000000000
R10: 000000000003fde0 R11: 0000000000000246 R12: 00000000000177c6
R13: 00007f6214744fac R14: 00000000000174b9 R15: 00007ffc3a09eb70
</TASK>


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