============================================
WARNING: possible recursive locking detected
6.8.0-syzkaller-08073-g480e035fc4c7 #0 Not tainted
--------------------------------------------
kworker/u8:5/605 is trying to acquire lock:
ffff88807a660da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88807a660da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: hsr_dev_xmit+0x13e/0x1d0 net/hsr/hsr_device.c:229
but task is already holding lock:
ffff88802a512da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88802a512da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x276/0xad0 net/hsr/hsr_device.c:310
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&hsr->seqnr_lock);
lock(&hsr->seqnr_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
10 locks held by kworker/u8:5/605:
#0: ffff88802abd8948 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline]
#0: ffff88802abd8948 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x1770 kernel/workqueue.c:3335
#1: ffffc90003ca7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline]
#1: ffffc90003ca7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x1770 kernel/workqueue.c:3335
#2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
#2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: batadv_nc_worker+0xcb/0x610 net/batman-adv/network-coding.c:719
#3: ffffc90000a08c00 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1789
#4: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#4: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#4: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hsr_announce+0xa3/0x370 net/hsr/hsr_device.c:387
#5: ffff88802a512da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#5: ffff88802a512da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x276/0xad0 net/hsr/hsr_device.c:310
#6: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#6: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#6: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hsr_forward_skb+0xae/0x2400 net/hsr/hsr_forward.c:614
#7: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
#7: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4260
#8: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
#8: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
#8: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: br_dev_xmit+0x1b9/0x1a10 net/bridge/br_device.c:44
#9: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#9: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
#9: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4260
stack backtrace:
CPU: 1 PID: 605 Comm: kworker/u8:5 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: bat_events batadv_nc_worker
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
check_deadlock kernel/locking/lockdep.c:3062 [inline]
validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
hsr_dev_xmit+0x13e/0x1d0 net/hsr/hsr_device.c:229
__netdev_start_xmit include/linux/netdevice.h:4903 [inline]
netdev_start_xmit include/linux/netdevice.h:4917 [inline]
xmit_one net/core/dev.c:3531 [inline]
dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547
__dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335
dev_queue_xmit include/linux/netdevice.h:3091 [inline]
br_dev_queue_push_xmit+0x701/0x8d0 net/bridge/br_forward.c:53
NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314
br_forward_finish+0xe5/0x140 net/bridge/br_forward.c:66
NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314
__br_forward+0x489/0x660 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver+0xb3/0x150 net/bridge/br_forward.c:190
br_flood+0x2e4/0x660 net/bridge/br_forward.c:236
br_dev_xmit+0x118c/0x1a10
__netdev_start_xmit include/linux/netdevice.h:4903 [inline]
netdev_start_xmit include/linux/netdevice.h:4917 [inline]
xmit_one net/core/dev.c:3531 [inline]
dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547
__dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335
dev_queue_xmit include/linux/netdevice.h:3091 [inline]
hsr_xmit net/hsr/hsr_forward.c:380 [inline]
hsr_forward_do net/hsr/hsr_forward.c:471 [inline]
hsr_forward_skb+0x183f/0x2400 net/hsr/hsr_forward.c:619
send_hsr_supervision_frame+0x548/0xad0 net/hsr/hsr_device.c:333
hsr_announce+0x1a9/0x370 net/hsr/hsr_device.c:389
call_timer_fn+0x17e/0x600 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers kernel/time/timer.c:2408 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2419
run_timer_base kernel/time/timer.c:2428 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2438
__do_softirq+0x2bc/0x943 kernel/softirq.c:554
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__preempt_count_add kernel/rcu/tree.c:696 [inline]
RIP: 0010:rcu_is_watching+0x6/0xb0 kernel/rcu/tree.c:699
Code: 64 03 e9 2b ff ff ff e8 d8 c8 f8 09 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 53 65 ff 05 78 66 88 7e e8 eb e6 f8 09 89 c3 83 f8 08 73 7a
RSP: 0018:ffffc90003ca7b48 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88801f493c00
RDX: ffff88801f493c00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8b407ace R09: 1ffffffff259c2a0
R10: dffffc0000000000 R11: fffffbfff259c2a1 R12: ffff88802eb3cca0
R13: 0000000000000072 R14: ffff88801e733c80 R15: dffffc0000000000
rcu_read_unlock include/linux/rcupdate.h:779 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0x207/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335
worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
vkms_vblank_simulate: vblank timer overrun
----------------
Code disassembly (best guess), 2 bytes skipped:
0: e9 2b ff ff ff jmp 0xffffff30
5: e8 d8 c8 f8 09 call 0x9f8c8e2
a: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1)
11: 00
12: 90 nop
13: 90 nop
14: 90 nop
15: 90 nop
16: 90 nop
17: 90 nop
18: 90 nop
19: 90 nop
1a: 90 nop
1b: 90 nop
1c: 90 nop
1d: 90 nop
1e: 90 nop
1f: 90 nop
20: 90 nop
21: 90 nop
22: f3 0f 1e fa endbr64
26: 41 57 push %r15
* 28: 41 56 push %r14 <-- trapping instruction
2a: 53 push %rbx
2b: 65 ff 05 78 66 88 7e incl %gs:0x7e886678(%rip) # 0x7e8866aa
32: e8 eb e6 f8 09 call 0x9f8e722
37: 89 c3 mov %eax,%ebx
39: 83 f8 08 cmp $0x8,%eax
3c: 73 7a jae 0xb8