============================================
WARNING: possible recursive locking detected
5.12.0-rc1-syzkaller #0 Not tainted
--------------------------------------------
syz-executor.3/7466 is trying to acquire lock:
ffff88811de49c98 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline]
ffff88811de49c98 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4261 [inline]
ffff88811de49c98 (_xmit_ETHER#2){+.-.}-{2:2}, at: __dev_queue_xmit+0x1b57/0x2690 net/core/dev.c:4178

but task is already holding lock:
ffff88811ac6f498 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline]
ffff88811ac6f498 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4261 [inline]
ffff88811ac6f498 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1ad/0x10c0 net/sched/sch_generic.c:311

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(_xmit_ETHER#2);
  lock(_xmit_ETHER#2);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

10 locks held by syz-executor.3/7466:
 #0: ffffffff894c3b00 (rcu_read_lock){....}-{1:2}, at: l3mdev_l3_out include/net/l3mdev.h:198 [inline]
 #0: ffffffff894c3b00 (rcu_read_lock){....}-{1:2}, at: l3mdev_ip6_out include/net/l3mdev.h:219 [inline]
 #0: ffffffff894c3b00 (rcu_read_lock){....}-{1:2}, at: rawv6_send_hdrinc net/ipv6/raw.c:677 [inline]
 #0: ffffffff894c3b00 (rcu_read_lock){....}-{1:2}, at: rawv6_sendmsg+0x178c/0x2fe0 net/ipv6/raw.c:944
 #1: ffffffff894c3aa0 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline]
 #1: ffffffff894c3aa0 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x14a/0x1540 net/ipv6/ip6_output.c:103
 #2: ffffffff894c3aa0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1be/0x2690 net/core/dev.c:4116
 #3: ffff888123873258 (&sch->seqlock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:364 [inline]
 #3: ffff888123873258 (&sch->seqlock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:162 [inline]
 #3: ffff888123873258 (&sch->seqlock){+...}-{2:2}, at: qdisc_run include/net/pkt_sched.h:130 [inline]
 #3: ffff888123873258 (&sch->seqlock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3795 [inline]
 #3: ffff888123873258 (&sch->seqlock){+...}-{2:2}, at: __dev_queue_xmit+0xf9c/0x2690 net/core/dev.c:4150
 #4: ffff888123873148 (dev->qdisc_running_key ?: &qdisc_running_key){+...}-{0:0}, at: neigh_hh_output include/net/neighbour.h:499 [inline]
 #4: ffff888123873148 (dev->qdisc_running_key ?: &qdisc_running_key){+...}-{0:0}, at: neigh_output include/net/neighbour.h:508 [inline]
 #4: ffff888123873148 (dev->qdisc_running_key ?: &qdisc_running_key){+...}-{0:0}, at: ip6_finish_output2+0x62b/0x1540 net/ipv6/ip6_output.c:117
 #5: ffff88811ac6f498 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline]
 #5: ffff88811ac6f498 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4261 [inline]
 #5: ffff88811ac6f498 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1ad/0x10c0 net/sched/sch_generic.c:311
 #6: ffff888124adc7e0 (k-slock-AF_INET6){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:364 [inline]
 #6: ffff888124adc7e0 (k-slock-AF_INET6){+...}-{2:2}, at: icmpv6_xmit_lock net/ipv6/icmp.c:117 [inline]
 #6: ffff888124adc7e0 (k-slock-AF_INET6){+...}-{2:2}, at: icmp6_send+0x993/0x1ca0 net/ipv6/icmp.c:547
 #7: ffffffff894c3b00 (rcu_read_lock){....}-{1:2}, at: icmp6_send+0xe9a/0x1ca0 net/ipv6/icmp.c:607
 #8: ffffffff894c3aa0 (rcu_read_lock_bh){....}-{1:2}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline]
 #8: ffffffff894c3aa0 (rcu_read_lock_bh){....}-{1:2}, at: ip6_finish_output2+0x14a/0x1540 net/ipv6/ip6_output.c:103
 #9: ffffffff894c3aa0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1be/0x2690 net/core/dev.c:4116

stack backtrace:
CPU: 0 PID: 7466 Comm: syz-executor.3 Not tainted 5.12.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x10c/0x14b lib/dump_stack.c:120
 print_deadlock_bug kernel/locking/lockdep.c:2829 [inline]
 check_deadlock kernel/locking/lockdep.c:2872 [inline]
 validate_chain kernel/locking/lockdep.c:3661 [inline]
 __lock_acquire.cold+0x227/0x3a6 kernel/locking/lockdep.c:4900
 lock_acquire kernel/locking/lockdep.c:5510 [inline]
 lock_acquire+0x212/0x850 kernel/locking/lockdep.c:5475
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 __netif_tx_lock include/linux/netdevice.h:4261 [inline]
 __dev_queue_xmit+0x1b57/0x2690 net/core/dev.c:4178
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0x62b/0x1540 net/ipv6/ip6_output.c:117
 ip6_send_skb+0x8f/0x2f0 net/ipv6/ip6_output.c:1904
 icmp6_send+0x152b/0x1ca0 net/ipv6/icmp.c:626
 __icmpv6_send include/linux/icmpv6.h:28 [inline]
 icmpv6_send include/linux/icmpv6.h:49 [inline]
 ip6_link_failure+0x21/0x390 net/ipv6/route.c:2673
 dst_link_failure include/net/dst.h:427 [inline]
 ip_tunnel_xmit+0x112e/0x2360 net/ipv4/ip_tunnel.c:811
 erspan_xmit+0x103a/0x2c50 net/ipv4/ip_gre.c:702
 __netdev_start_xmit include/linux/netdevice.h:4825 [inline]
 netdev_start_xmit include/linux/netdevice.h:4839 [inline]
 xmit_one net/core/dev.c:3593 [inline]
 dev_hard_start_xmit+0x1a5/0x6f0 net/core/dev.c:3609
 sch_direct_xmit+0x223/0x10c0 net/sched/sch_generic.c:313
 qdisc_restart net/sched/sch_generic.c:376 [inline]
 __qdisc_run+0x3d9/0x1480 net/sched/sch_generic.c:384
 qdisc_run include/net/pkt_sched.h:136 [inline]
 qdisc_run include/net/pkt_sched.h:128 [inline]
 __dev_xmit_skb net/core/dev.c:3795 [inline]
 __dev_queue_xmit+0x109b/0x2690 net/core/dev.c:4150
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0x62b/0x1540 net/ipv6/ip6_output.c:117
 dst_output include/net/dst.h:448 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 rawv6_send_hdrinc net/ipv6/raw.c:687 [inline]
 rawv6_sendmsg+0x196a/0x2fe0 net/ipv6/raw.c:944
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg+0xab/0xe0 net/socket.c:674
 sock_write_iter+0x211/0x370 net/socket.c:1001
 call_write_iter include/linux/fs.h:1977 [inline]
 new_sync_write+0x4ad/0x5f0 fs/read_write.c:518
 vfs_write+0x5c3/0x870 fs/read_write.c:605
 ksys_write+0x171/0x1d0 fs/read_write.c:658
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x464c39
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd94a9ff188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000055cf00 RCX: 0000000000464c39
RDX: 0000000000000028 RSI: 0000000020000140 RDI: 0000000000000005
RBP: 00000000004ae6c3 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055cf00
R13: 00007ffd488beeef R14: 00007fd94a9ff300 R15: 0000000000022000