[v6.1] INFO: rcu detected stall in wext_handle_ioctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 228da13e907e Linux 6.1.175
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16f8dbec580000
kernel config: https://syzkaller.appspot.com/x/.config?x=4dd3c1715f0a309b
dashboard link: https://syzkaller.appspot.com/bug?extid=6d4fd792728f4ac890d1
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/894d01ce6736/disk-228da13e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2a4cec18e217/vmlinux-228da13e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/32550387ebe8/bzImage-228da13e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6d4fd7...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2656 jiffies s: 149133 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 27843 Comm: syz.3.6181 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2a/0x60 kernel/kcov.c:216
Code: 48 8b 04 24 65 48 8b 0d 94 f3 7f 7e 65 8b 15 95 f3 7f 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 <74> 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b
RSP: 0018:ffffc900001e0748 EFLAGS: 00000046
RAX: ffffffff81a59e76 RBX: 0000000000000001 RCX: ffff888081c59e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff8880b8f3580b R09: 1ffff110171e6b01
R10: dffffc0000000000 R11: ffffed10171e6b02 R12: 1ffff110171e6a93
R13: dffffc0000000000 R14: ffff8880b8f35498 R15: dffffc0000000000
FS: 00007f55b78866c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000004 CR3: 0000000068534000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000008d24
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
get_recursion_context kernel/events/internal.h:219 [inline]
perf_swevent_get_recursion_context+0xe6/0x150 kernel/events/core.c:9755
perf_trace_buf_alloc+0x54/0x300 kernel/trace/trace_event_perf.c:414
perf_trace_preemptirq_template+0x143/0x320 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 82 30 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:ffffc900001e0980 EFLAGS: 00000206
RAX: 76a4cb8362623900 RBX: 1ffff9200003c138 RCX: 76a4cb8362623900
RDX: dffffc0000000000 RSI: ffffffff8a8c1aa0 RDI: ffffffff8adf2060
RBP: ffffc900001e0a80 R08: ffffffff90aff32f R09: 1ffffffff215fe65
R10: dffffc0000000000 R11: fffffbfff215fe66 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
hsr_announce+0x2ca/0x340 net/hsr/hsr_device.c:407
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:check_region_inline mm/kasan/generic.c:169 [inline]
RIP: 0010:kasan_check_range+0x12/0x290 mm/kasan/generic.c:189
Code: ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc b0 01 48 85 f6 0f 84 ac 01 00 00 55 41 57 41 56 41 54 <53> 49 89 f8 49 01 f0 0f 82 0e 02 00 00 49 89 f8 49 c1 e8 2f 41 81
RSP: 0018:ffffc90003417a60 EFLAGS: 00000202
RAX: 1ffff1101038b301 RBX: ffffffff8dd4abd0 RCX: ffffffff8163a21b
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8dd4ab80
RBP: 1ffffffff1ba9570 R08: ffff888081c59e07 R09: 1ffff1101038b3c0
R10: dffffc0000000000 R11: ffffed101038b3c1 R12: ffffffff8dd4ab80
R13: ffffffff8dd4abd0 R14: dffffc0000000000 R15: ffff8880242a5a00
instrument_atomic_read include/linux/instrumented.h:72 [inline]
atomic_long_read include/linux/atomic/atomic-instrumented.h:1265 [inline]
__mutex_owner kernel/locking/mutex.c:81 [inline]
mutex_spin_on_owner+0x28b/0x350 kernel/locking/mutex.c:359
mutex_optimistic_spin kernel/locking/mutex.c:476 [inline]
__mutex_lock_common kernel/locking/mutex.c:607 [inline]
__mutex_lock+0x187/0xaf0 kernel/locking/mutex.c:747
wext_ioctl_dispatch+0xaf/0x470 net/wireless/wext-core.c:996
wext_handle_ioctl+0x113/0x1d0 net/wireless/wext-core.c:1058
sock_ioctl+0x143/0x710 net/socket.c:1252
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
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: 0033:0x7f55b699ce59
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:00007f55b7886028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f55b6c15fa0 RCX: 00007f55b699ce59
RDX: 0000200000000000 RSI: 0000000000008b34 RDI: 000000000000000d
RBP: 00007f55b6a32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55b6c16038 R14: 00007f55b6c15fa0 R15: 00007ffc5baf50e8
</TASK>


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