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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e45d5d41c134 Linux 5.15.200
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=115e295a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=3a0e09fd3ca59170f354
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/79bf32e4dfac/disk-e45d5d41.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/13e2c5c833d9/vmlinux-e45d5d41.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8af7798ac1cf/bzImage-e45d5d41.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3a0e09...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-....: (1 GPs behind) idle=f3b/1/0x4000000000000002 softirq=19484/19485 fqs=5250
(detected by 0, t=10502 jiffies, g=27953, q=642)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6771 Comm: syz.0.732 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:perf_prepare_sample+0x1105/0x1cd0 kernel/events/core.c:7736
Code: 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 3d 3e 26 00 49 89 1e 4c 8b 74 24 20 4c 89 f6 48 81 e6 00 00 20 00 <31> ff e8 a4 35 e1 ff 4c 89 f0 48 25 00 00 20 00 75 0a e8 b4 31 e1
RSP: 0018:ffffc90000dd03c0 EFLAGS: 00000046
RAX: ffffffff8197ed24 RBX: ffffc90000dd0560 RCX: ffff88807b0e3b80
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000dd04b0 R08: ffffffff8f0e7048 R09: ffffffff8f0e7058
R10: ffffffff8f0e7050 R11: ffffffff8f0e7043 R12: dffffc0000000000
R13: ffffc90000dd0566 R14: 0000000000010104 R15: ffffc90000dd06c0
FS: 00007faaee61f6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000cf000 CR3: 000000005e969000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
__perf_event_output kernel/events/core.c:7802 [inline]
perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7822
__perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
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 e2 f0 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:ffffc90000dd0b00 EFLAGS: 00000206
RAX: 7d7c5c3f691b3400 RBX: 1ffff920001ba164 RCX: 7d7c5c3f691b3400
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f740
RBP: ffffc90000dd0bd8 R08: ffffffff901d2177 R09: 1ffffffff203a42e
R10: dffffc0000000000 R11: fffffbfff203a42f R12: ffffffff8c322f00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000002
__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+0x4eb/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:clear_page_erms+0x7/0x10 arch/x86/lib/clear_page_64.S:49
Code: 48 89 47 18 48 89 47 20 48 89 47 28 48 89 47 30 48 89 47 38 48 8d 7f 40 75 d9 90 c3 90 90 90 90 90 90 90 b9 00 10 00 00 31 c0 <f3> aa c3 00 00 cc cc 00 00 55 41 57 41 56 41 55 41 54 53 48 83 ec
RSP: 0018:ffffc9000150f770 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888059fd2000 RCX: 00000000000002c0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888059fd2d40
RBP: 0000000000500cc2 R08: ffffea000167f4b7 R09: ffffed100b3fa400
R10: dffffc0000000000 R11: fffff940002cfe97 R12: 0000000000000001
R13: 1ffff1100f61ca61 R14: ffff88807b0e5308 R15: dffffc0000000000
clear_page arch/x86/include/asm/page_64.h:49 [inline]
clear_highpage include/linux/highmem.h:181 [inline]
kernel_init_free_pages+0x7c/0xf0 mm/page_alloc.c:1278
post_alloc_hook+0x106/0x220 mm/page_alloc.c:2416
prep_new_page mm/page_alloc.c:2426 [inline]
get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
__alloc_pages+0x1ee/0x480 mm/page_alloc.c:5487
pipe_write+0x5d2/0x1aa0 fs/pipe.c:500
call_write_iter include/linux/fs.h:2173 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x745/0xd60 fs/read_write.c:594
ksys_write+0x152/0x260 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7faaf03e5f79
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:00007faaee61f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007faaf0660090 RCX: 00007faaf03e5f79
RDX: 00000000fffffd8f RSI: 00002000000010c0 RDI: 0000000000000000
RBP: 00007faaf047c7e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faaf0660128 R14: 00007faaf0660090 R15: 00007fffd2ba9de8
</TASK>


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