============================================ WARNING: possible recursive locking detected 5.15.178-syzkaller #0 Not tainted -------------------------------------------- syz.1.760/6894 is trying to acquire lock: ffff0000d992ca18 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] ffff0000d992ca18 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3877 [inline] ffff0000d992ca18 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1964/0x2ac8 net/core/dev.c:4221 but task is already holding lock: ffff0000cecb0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: spin_trylock include/linux/spinlock.h:373 [inline] ffff0000cecb0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: qdisc_run_begin+0x130/0x2bc include/net/sch_generic.h:173 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); *** DEADLOCK *** May be due to missing lock nesting notation 9 locks held by syz.1.760/6894: #0: ffff800008017ba0 ((&ndev->rs_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline] #0: ffff800008017ba0 ((&ndev->rs_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd0/0x8f0 kernel/time/timer.c:1441 #1: ffff800014d42360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311 #2: ffff800014d423c0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 #3: ffff800014d423c0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 #4: ffff800014d42360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311 #5: ffff800014d423c0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 #6: ffff0000cecb0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: spin_trylock include/linux/spinlock.h:373 [inline] #6: ffff0000cecb0258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-.}-{2:2}, at: qdisc_run_begin+0x130/0x2bc include/net/sch_generic.h:173 #7: ffff800014d423c0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 #8: ffff800014d423c0 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 6894 Comm: syz.1.760 Not tainted 5.15.178-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 __lock_acquire+0x62bc/0x7638 kernel/locking/lockdep.c:5012 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0xb0/0x10c kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] __dev_xmit_skb net/core/dev.c:3877 [inline] __dev_queue_xmit+0x1964/0x2ac8 net/core/dev.c:4221 dev_queue_xmit+0x24/0x34 net/core/dev.c:4289 neigh_hh_output include/net/neighbour.h:493 [inline] neigh_output include/net/neighbour.h:507 [inline] ip_finish_output2+0xd3c/0x131c net/ipv4/ip_output.c:228 __ip_finish_output+0x1b0/0x458 ip_finish_output+0x40/0x218 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip_output+0x330/0x49c net/ipv4/ip_output.c:430 dst_output include/net/dst.h:443 [inline] ip_local_out+0x120/0x160 net/ipv4/ip_output.c:126 iptunnel_xmit+0x40c/0x8fc net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x1a00/0x2184 net/ipv4/ip_tunnel.c:838 __gre_xmit net/ipv4/ip_gre.c:474 [inline] gre_tap_xmit+0x404/0x5f0 net/ipv4/ip_gre.c:751 __netdev_start_xmit include/linux/netdevice.h:5019 [inline] netdev_start_xmit include/linux/netdevice.h:5033 [inline] xmit_one net/core/dev.c:3617 [inline] dev_hard_start_xmit+0x2bc/0x92c net/core/dev.c:3633 sch_direct_xmit+0x2e0/0x484 net/sched/sch_generic.c:342 __dev_xmit_skb net/core/dev.c:3852 [inline] __dev_queue_xmit+0x1488/0x2ac8 net/core/dev.c:4221 dev_queue_xmit+0x24/0x34 net/core/dev.c:4289 bond_dev_queue_xmit+0x94/0x134 drivers/net/bonding/bond_main.c:304 bond_do_alb_xmit+0x558/0x70c drivers/net/bonding/bond_alb.c:1327 bond_tlb_xmit+0x3c/0x4c drivers/net/bonding/bond_alb.c:1382 __bond_start_xmit drivers/net/bonding/bond_main.c:5142 [inline] bond_start_xmit+0xa78/0x1550 drivers/net/bonding/bond_main.c:5164 __netdev_start_xmit include/linux/netdevice.h:5019 [inline] netdev_start_xmit include/linux/netdevice.h:5033 [inline] xmit_one net/core/dev.c:3617 [inline] dev_hard_start_xmit+0x2bc/0x92c net/core/dev.c:3633 __dev_queue_xmit+0x1378/0x2ac8 net/core/dev.c:4256 dev_queue_xmit+0x24/0x34 net/core/dev.c:4289 neigh_hh_output include/net/neighbour.h:493 [inline] neigh_output include/net/neighbour.h:507 [inline] ip6_finish_output2+0x132c/0x1cec net/ipv6/ip6_output.c:130 __ip6_finish_output+0x580/0x6ec net/ipv6/ip6_output.c:201 ip6_finish_output+0x40/0x218 net/ipv6/ip6_output.c:211 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x274/0x594 net/ipv6/ip6_output.c:234 dst_output include/net/dst.h:443 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] ndisc_send_skb+0xbf8/0x1788 net/ipv6/ndisc.c:511 ndisc_send_rs+0x494/0x5fc net/ipv6/ndisc.c:705 addrconf_rs_timer+0x308/0x5a8 net/ipv6/addrconf.c:3959 call_timer_fn+0x19c/0x8f0 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x554/0x718 kernel/time/timer.c:1767 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1780 handle_softirqs+0x384/0xdbc kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] invoke_softirq kernel/softirq.c:439 [inline] __irq_exit_rcu+0x268/0x4d8 kernel/softirq.c:641 irq_exit+0x14/0x88 kernel/softirq.c:665 handle_domain_irq+0xf4/0x178 kernel/irq/irqdesc.c:711 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:765 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:899 do_interrupt_handler+0x74/0x94 arch/arm64/kernel/entry-common.c:267 el1_interrupt+0x30/0x58 arch/arm64/kernel/entry-common.c:454 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:522 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irqrestore+0xbc/0x158 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:982 [inline] debug_check_no_obj_freed+0x45c/0x478 lib/debugobjects.c:1003 free_pages_prepare mm/page_alloc.c:1345 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x32c/0xe30 mm/page_alloc.c:3317 free_unref_page_list+0xe4/0x7a8 mm/page_alloc.c:3433 release_pages+0x1770/0x1a88 mm/swap.c:963 __pagevec_release+0x94/0x10c mm/swap.c:983 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x578/0x1460 mm/shmem.c:964 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_evict_inode+0x1c4/0x844 mm/shmem.c:1145 evict+0x418/0x894 fs/inode.c:622 iput_final fs/inode.c:1744 [inline] iput+0x744/0x824 fs/inode.c:1770 dentry_unlink_inode+0x37c/0x4bc fs/dcache.c:380 __dentry_kill+0x324/0x5e4 fs/dcache.c:586 dentry_kill+0xc8/0x250 dput+0x21c/0x458 fs/dcache.c:893 __fput+0x494/0x800 fs/file_table.c:288 ____fput+0x20/0x30 fs/file_table.c:308 task_work_run+0x130/0x1e4 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584