[v5.15] BUG: soft lockup in fuse_dev_read

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 14e468424d3e Linux 5.15.166
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=12af509f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=b908c0674f314233
dashboard link: https://syzkaller.appspot.com/bug?extid=9e785824e688438b6f45
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/86629e9b1d25/disk-14e46842.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f91d8cebb80b/vmlinux-14e46842.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1e46d568a2b5/Image-14e46842.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9e7858...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [syz.0.218:4928]
Modules linked in:
irq event stamp: 5854
hardirqs last enabled at (5853): [<ffff800011ab6900>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:81 [inline]
hardirqs last enabled at (5853): [<ffff800011ab6900>] exit_to_kernel_mode+0x100/0x178 arch/arm64/kernel/entry-common.c:91
hardirqs last disabled at (5854): [<ffff800011ab6b48>] enter_el1_irq_or_nmi+0x10/0x1c arch/arm64/kernel/entry-common.c:227
softirqs last enabled at (1326): [<ffff8000081b6d74>] softirq_handle_end kernel/softirq.c:401 [inline]
softirqs last enabled at (1326): [<ffff8000081b6d74>] handle_softirqs+0xb88/0xdbc kernel/softirq.c:586
softirqs last disabled at (1229): [<ffff8000081b740c>] __do_softirq kernel/softirq.c:592 [inline]
softirqs last disabled at (1229): [<ffff8000081b740c>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
softirqs last disabled at (1229): [<ffff8000081b740c>] invoke_softirq kernel/softirq.c:439 [inline]
softirqs last disabled at (1229): [<ffff8000081b740c>] __irq_exit_rcu+0x268/0x4d8 kernel/softirq.c:641
CPU: 0 PID: 4928 Comm: syz.0.218 Not tainted 5.15.166-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : queued_spin_lock_slowpath+0x160/0x938 kernel/locking/qspinlock.c:382
lr : queued_spin_lock_slowpath+0x16c/0x938 kernel/locking/qspinlock.c:382
sp : ffff8000208975e0
x29: ffff800020897680 x28: 1ffff00004112ec8 x27: 1fffe0001c840e12
x26: dfff800000000000 x25: ffff700004112ec0 x24: ffff800020897600
x23: 1fffe0001c840e11 x22: ffff800020897640 x21: 0000000000000001
x20: 0000000000000001 x19: ffff0000e4207088 x18: 1fffe00036831f8e
x17: 1fffe00036831f8e x16: ffff8000083052b0 x15: ffff80000897b6e0
x14: 1ffff0000295606a x13: dfff800000000000 x12: 0000000000000001
x11: 1fffe0001c840e11 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000101 x7 : ffff8000097a3c80 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff8000083044d8
x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001
Call trace:
__cmpwait_case_32 arch/arm64/include/asm/cmpxchg.h:252 [inline]
__cmpwait arch/arm64/include/asm/cmpxchg.h:278 [inline]
queued_spin_lock_slowpath+0x160/0x938 kernel/locking/qspinlock.c:382
queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
do_raw_spin_lock+0x334/0x35c kernel/locking/spinlock_debug.c:115
__raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_lock+0xb8/0x10c kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:363 [inline]
fuse_dev_do_read+0x174/0xe2c fs/fuse/dev.c:1241
fuse_dev_read+0x164/0x1e8 fs/fuse/dev.c:1372
call_read_iter include/linux/fs.h:2166 [inline]
new_sync_read fs/read_write.c:404 [inline]
vfs_read+0x874/0xb18 fs/read_write.c:485
ksys_read+0x15c/0x26c fs/read_write.c:623
__do_sys_read fs/read_write.c:633 [inline]
__se_sys_read fs/read_write.c:631 [inline]
__arm64_sys_read+0x7c/0x90 fs/read_write.c:631
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.