===================================== WARNING: bad unlock balance detected! 5.5.0-rc5-syzkaller #0 Not tainted ------------------------------------- modprobe/12074 is trying to release lock (&dev->qdisc_xmit_lock_key) at: [] spin_unlock include/linux/spinlock.h:378 [inline] [] __netif_tx_unlock include/linux/netdevice.h:3966 [inline] [] sch_direct_xmit+0x3fa/0xd30 net/sched/sch_generic.c:315 but there are no more locks to release! other info that might help us debug this: 9 locks held by modprobe/12074: #0: ffff8880617c5358 (&mm->mmap_sem#2){++++}, at: do_user_addr_fault arch/x86/mm/fault.c:1382 [inline] #0: ffff8880617c5358 (&mm->mmap_sem#2){++++}, at: __do_page_fault+0x33c/0xd80 arch/x86/mm/fault.c:1506 #1: ffffffff899a5340 (rcu_read_lock){....}, at: filemap_map_pages+0x105/0x14e0 mm/filemap.c:2606 #2: ffff88809fa02330 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline] #2: ffff88809fa02330 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: pte_alloc_one_map mm/memory.c:3316 [inline] #2: ffff88809fa02330 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: alloc_set_pte+0xc12/0x1800 mm/memory.c:3434 #3: ffffc90000da8d50 ((&ndev->rs_timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:172 [inline] #3: ffffc90000da8d50 ((&ndev->rs_timer)){+.-.}, at: call_timer_fn+0xe0/0x780 kernel/time/timer.c:1394 #4: ffffffff899a5340 (rcu_read_lock){....}, at: ip6_nd_hdr net/ipv6/ndisc.c:463 [inline] #4: ffffffff899a5340 (rcu_read_lock){....}, at: ndisc_send_skb+0x7fe/0x1490 net/ipv6/ndisc.c:499 #5: ffffffff899a5300 (rcu_read_lock_bh){....}, at: lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline] #5: ffffffff899a5300 (rcu_read_lock_bh){....}, at: ip6_finish_output2+0x214/0x25c0 net/ipv6/ip6_output.c:102 #6: ffffffff899a5300 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x20a/0x35c0 net/core/dev.c:3948 #7: ffff888092454250 (&dev->qdisc_tx_busylock_key#20){+...}, at: spin_trylock include/linux/spinlock.h:348 [inline] #7: ffff888092454250 (&dev->qdisc_tx_busylock_key#20){+...}, at: qdisc_run_begin include/net/sch_generic.h:159 [inline] #7: ffff888092454250 (&dev->qdisc_tx_busylock_key#20){+...}, at: __dev_xmit_skb net/core/dev.c:3611 [inline] #7: ffff888092454250 (&dev->qdisc_tx_busylock_key#20){+...}, at: __dev_queue_xmit+0x2412/0x35c0 net/core/dev.c:3982 #8: ffff888092454138 (&dev->qdisc_running_key#20){+...}, at: dev_queue_xmit+0x18/0x20 net/core/dev.c:4046 stack backtrace: CPU: 1 PID: 12074 Comm: modprobe Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_unlock_imbalance_bug kernel/locking/lockdep.c:4008 [inline] print_unlock_imbalance_bug.cold+0x114/0x123 kernel/locking/lockdep.c:3984 __lock_release kernel/locking/lockdep.c:4242 [inline] lock_release+0x5f2/0x960 kernel/locking/lockdep.c:4503 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_unlock+0x16/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:378 [inline] __netif_tx_unlock include/linux/netdevice.h:3966 [inline] sch_direct_xmit+0x3fa/0xd30 net/sched/sch_generic.c:315 __dev_xmit_skb net/core/dev.c:3621 [inline] __dev_queue_xmit+0x2707/0x35c0 net/core/dev.c:3982 dev_queue_xmit+0x18/0x20 net/core/dev.c:4046 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip6_finish_output2+0xfbe/0x25c0 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x444/0xaa0 net/ipv6/ip6_output.c:142 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x25e/0x880 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xf1f/0x1490 net/ipv6/ndisc.c:505 ndisc_send_rs+0x134/0x720 net/ipv6/ndisc.c:699 addrconf_rs_timer+0x30f/0x6e0 net/ipv6/addrconf.c:3879 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:747 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:769 [inline] RIP: 0010:lock_is_held_type+0x69/0x320 kernel/locking/lockdep.c:4518 Code: f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 4d 02 00 00 41 8b 94 24 94 08 00 00 85 d2 0f 85 2f 02 00 00 48 c7 c0 d0 34 93 89 <48> ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 58 02 RSP: 0000:ffffc90001b47b48 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff899334d0 RBX: ffffea0002ba5880 RCX: ffffffff819326e1 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff88805b494994 RBP: ffffc90001b47b90 R08: ffff88805b494100 R09: fffff94000574b09 R10: fffff94000574b08 R11: ffffea0002ba5847 R12: ffff88805b494100 R13: ffff8880a1ea47d8 R14: ffff8880a1ea47f0 R15: 00000000000000bb lock_is_held include/linux/lockdep.h:361 [inline] xa_entry include/linux/xarray.h:1145 [inline] xas_next_entry include/linux/xarray.h:1569 [inline] filemap_map_pages+0xab8/0x14e0 mm/filemap.c:2613 do_fault_around mm/memory.c:3598 [inline] do_read_fault mm/memory.c:3632 [inline] do_fault mm/memory.c:3766 [inline] handle_pte_fault mm/memory.c:3997 [inline] __handle_mm_fault+0x2de6/0x3cc0 mm/memory.c:4127 handle_mm_fault+0x3b2/0xa50 mm/memory.c:4164 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline] __do_page_fault+0x536/0xd80 arch/x86/mm/fault.c:1506 do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203 RIP: 0033:0x7f00622fc390 Code: Bad RIP value. RSP: 002b:00007ffca5422088 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 00007ffca5423428 RCX: 00005578250c3660 RDX: 0000557824ebe7f0 RSI: 00007ffca5423428 RDI: 0000000000000004 RBP: 00007ffca5423428 R08: 00007ffca54220fc R09: 0000000000000000 R10: 0000000000000000 R11: 00007f00622fc390 R12: 0000000000000004 R13: 0000557824ebe608 R14: 0000000000000000 R15: 0000000000000000