[syzbot] [wireguard?] WARNING in kthread_unpark

From: syzbot
Date: Sun Oct 08 2023 - 11:27:53 EST


Hello,

syzbot found the following issue on:

HEAD commit: 2e530aeb342b Merge branch 'for-next/core', remote-tracking..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=13ef2062680000
kernel config: https://syzkaller.appspot.com/x/.config?x=5cc95add722fb0c1
dashboard link: https://syzkaller.appspot.com/bug?extid=66ff56c4661498a22ae8
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/2468ab4c933e/disk-2e530aeb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bd3708bf8a20/vmlinux-2e530aeb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/86bc7d3468f9/Image-2e530aeb.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+66ff56c4661498a22ae8@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 1 PID: 11 at kernel/kthread.c:524 __kthread_bind kernel/kthread.c:537 [inline]
WARNING: CPU: 1 PID: 11 at kernel/kthread.c:524 kthread_unpark+0x148/0x204 kernel/kthread.c:630
Modules linked in:
CPU: 1 PID: 11 Comm: kworker/u4:0 Not tainted 6.6.0-rc3-syzkaller-g2e530aeb342b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
Workqueue: netns cleanup_net
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __kthread_bind kernel/kthread.c:537 [inline]
pc : kthread_unpark+0x148/0x204 kernel/kthread.c:630
lr : __kthread_bind kernel/kthread.c:537 [inline]
lr : kthread_unpark+0x148/0x204 kernel/kthread.c:630
sp : ffff800092b376d0
x29: ffff800092b376d0 x28: ffff0000c63f0000 x27: dfff800000000000
x26: 1fffe00019602005 x25: dfff800000000000 x24: 1fffe00018c7e29c
x23: 0000000000000000 x22: 0000000000000000 x21: ffff0000cd704400
x20: ffff0000cb01002c x19: ffff0000cb010000 x18: ffff800092b371c0
x17: ffff80008e19d000 x16: ffff8000802771bc x15: 0000000000000001
x14: 1fffe00019602130 x13: 0000000000000000 x12: 0000000000000003
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : ffff0000c199b780 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000020 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000006 x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
__kthread_bind kernel/kthread.c:537 [inline]
kthread_unpark+0x148/0x204 kernel/kthread.c:630
kthread_stop+0x188/0x704 kernel/kthread.c:706
destroy_workqueue+0x124/0xdc4 kernel/workqueue.c:4805
wg_destruct+0x1c8/0x2dc drivers/net/wireguard/device.c:258
netdev_run_todo+0xc34/0xe08 net/core/dev.c:10445
rtnl_unlock+0x14/0x20 net/core/rtnetlink.c:151
default_device_exit_batch+0x6cc/0x744 net/core/dev.c:11454
ops_exit_list net/core/net_namespace.c:175 [inline]
cleanup_net+0x5dc/0x8d0 net/core/net_namespace.c:614
process_one_work+0x694/0x1204 kernel/workqueue.c:2630
process_scheduled_works kernel/workqueue.c:2703 [inline]
worker_thread+0x938/0xef4 kernel/workqueue.c:2784
kthread+0x288/0x310 kernel/kthread.c:388
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857
irq event stamp: 8730562
hardirqs last enabled at (8730561): [<ffff80008a7140e8>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
hardirqs last enabled at (8730561): [<ffff80008a7140e8>] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194
hardirqs last disabled at (8730562): [<ffff80008a625394>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:436
softirqs last enabled at (8730490): [<ffff800084cff268>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last enabled at (8730490): [<ffff800084cff268>] wg_packet_purge_staged_packets+0x1b8/0x1f4 drivers/net/wireguard/send.c:338
softirqs last disabled at (8730488): [<ffff800084cff0ec>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (8730488): [<ffff800084cff0ec>] wg_packet_purge_staged_packets+0x3c/0x1f4 drivers/net/wireguard/send.c:335
---[ end trace 0000000000000000 ]---


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