[moderation] [net?] [virt?] [kvm?] BUG: soft lockup in vsock_loopback_work

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e7c375b18160 Merge tag 'vfs-6.18-rc7.fixes' of gitolite.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=121cfb42580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c473789166ef75a5
dashboard link: https://syzkaller.appspot.com/bug?extid=4fbf9927edd1c06bf08f
compiler: arm-linux-gnueabi-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm
CC: [da...@davemloft.net edum...@google.com eper...@redhat.com ho...@kernel.org jaso...@redhat.com ku...@kernel.org k...@vger.kernel.org linux-...@vger.kernel.org m...@redhat.com net...@vger.kernel.org pab...@redhat.com sgar...@redhat.com stef...@redhat.com virtual...@lists.linux.dev xuan...@linux.alibaba.com]

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/98a89b9f34e4/non_bootable_disk-e7c375b1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/474d6d613c09/vmlinux-e7c375b1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9cfbda18d15c/zImage-e7c375b1.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4fbf99...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#1 stuck for 460s! [kworker/1:6:18885]
Modules linked in:
CPU: 1 UID: 0 PID: 18885 Comm: kworker/1:6 Not tainted syzkaller #0 PREEMPT
Hardware name: ARM-Versatile Express
Workqueue: vsock-loopback vsock_loopback_work
PC is at arch_spin_lock arch/arm/include/asm/spinlock.h:74 [inline]
PC is at do_raw_spin_lock include/linux/spinlock.h:187 [inline]
PC is at __raw_spin_lock_bh include/linux/spinlock_api_smp.h:127 [inline]
PC is at _raw_spin_lock_bh+0x40/0x58 kernel/locking/spinlock.c:178
LR is at get_lock_parent_ip include/linux/ftrace.h:1102 [inline]
LR is at preempt_latency_start kernel/sched/core.c:5775 [inline]
LR is at preempt_count_add+0x12c/0x150 kernel/sched/core.c:5800
pc : [<81a6de50>] lr : [<8028fe9c>] psr: 80000013
sp : df9cdda8 ip : df9cdd80 fp : df9cddbc
r10: 846a8b70 r9 : 83c92c05 r8 : 838f5400
r7 : 829faaf0 r6 : 85b91880 r5 : 85b91970 r4 : 85b91970
r3 : 00000008 r2 : 00000009 r1 : 00000000 r0 : 00000000
Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 30c5387d Table: 848af1c0 DAC: 00000000
Call trace:
[<81a6de10>] (_raw_spin_lock_bh) from [<8155efe8>] (spin_lock_bh include/linux/spinlock.h:356 [inline])
[<81a6de10>] (_raw_spin_lock_bh) from [<8155efe8>] (lock_sock_nested+0x1c/0x48 net/core/sock.c:3723)
r5:85b91970 r4:85b91880
[<8155efcc>] (lock_sock_nested) from [<819eaefc>] (lock_sock include/net/sock.h:1679 [inline])
[<8155efcc>] (lock_sock_nested) from [<819eaefc>] (virtio_transport_recv_pkt+0x350/0xa4c net/vmw_vsock/virtio_transport_common.c:1631)
r5:8ddf7780 r4:85b918e4
[<819eabac>] (virtio_transport_recv_pkt) from [<819eb7b4>] (vsock_loopback_work+0xf4/0x128 net/vmw_vsock/vsock_loopback.c:133)
r10:846a8b70 r9:83c92c05 r8:829faaf0 r7:00000000 r6:00000000 r5:df9cde98
r4:8ddf7780
[<819eb6c0>] (vsock_loopback_work) from [<802785a0>] (process_one_work+0x1b4/0x4f4 kernel/workqueue.c:3263)
r8:838f5400 r7:ddde3d80 r6:83c92c00 r5:82c3de40 r4:830cf000
[<802783ec>] (process_one_work) from [<802791e8>] (process_scheduled_works kernel/workqueue.c:3346 [inline])
[<802783ec>] (process_one_work) from [<802791e8>] (worker_thread+0x1fc/0x3d8 kernel/workqueue.c:3427)
r10:61c88647 r9:838f5400 r8:830cf02c r7:82804d40 r6:ddde3d80 r5:ddde3da0
r4:830cf000
[<80278fec>] (worker_thread) from [<8028020c>] (kthread+0x12c/0x280 kernel/kthread.c:463)
r10:00000000 r9:830cf000 r8:80278fec r7:dfb79e60 r6:8db08900 r5:838f5400
r4:00000001
[<802800e0>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdf9cdfb0 to 0xdf9cdff8)
dfa0: 00000000 00000000 00000000 00000000
dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:802800e0
r4:849cc940
Sending NMI from CPU 1 to CPUs 0:


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