============================================ WARNING: possible recursive locking detected 5.15.160-syzkaller #0 Not tainted -------------------------------------------- syz-executor.0/4739 is trying to acquire lock: ffff0000ce96ad88 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] ffff0000ce96ad88 (&hsr->seqnr_lock){+.-.}-{2:2}, at: hsr_dev_xmit+0xf8/0x1d0 net/hsr/hsr_device.c:222 but task is already holding lock: ffff0000d4c28d88 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] ffff0000d4c28d88 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x1fc/0x8a4 net/hsr/hsr_device.c:303 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 7 locks held by syz-executor.0/4739: #0: ffff800008017ba0 ((&hsr->announce_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline] #0: ffff800008017ba0 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd0/0x8f0 kernel/time/timer.c:1441 #1: ffff800014b214a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311 #2: ffff0000d4c28d88 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:368 [inline] #2: ffff0000d4c28d88 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x1fc/0x8a4 net/hsr/hsr_device.c:303 #3: ffff800014b214a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311 #4: ffff800014b21500 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 #5: ffff800014b214a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311 #6: ffff800014b21500 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x18/0x54 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 4739 Comm: syz-executor.0 Not tainted 5.15.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 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_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x124/0x1c4 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] hsr_dev_xmit+0xf8/0x1d0 net/hsr/hsr_device.c:222 __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+0x13a8/0x2a6c net/core/dev.c:4248 dev_queue_xmit+0x24/0x34 net/core/dev.c:4281 br_dev_queue_push_xmit+0x56c/0x70c net/bridge/br_forward.c:53 NF_HOOK+0x358/0x404 include/linux/netfilter.h:302 br_forward_finish+0x7c/0x90 net/bridge/br_forward.c:66 NF_HOOK+0x358/0x404 include/linux/netfilter.h:302 __br_forward+0x2f0/0x458 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xc8/0x188 net/bridge/br_forward.c:189 br_flood+0x28c/0x41c net/bridge/br_forward.c:231 br_dev_xmit+0xca8/0x1194 __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+0x13a8/0x2a6c net/core/dev.c:4248 dev_queue_xmit+0x24/0x34 net/core/dev.c:4281 hsr_xmit net/hsr/hsr_forward.c:338 [inline] hsr_forward_do net/hsr/hsr_forward.c:429 [inline] hsr_forward_skb+0xe78/0x15a8 net/hsr/hsr_forward.c:577 send_hsr_supervision_frame+0x414/0x8a4 net/hsr/hsr_device.c:326 hsr_announce+0x17c/0x31c net/hsr/hsr_device.c:382 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 __do_softirq+0x344/0xdb0 kernel/softirq.c:558 do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] invoke_softirq kernel/softirq.c:439 [inline] __irq_exit_rcu+0x264/0x4d4 kernel/softirq.c:637 irq_exit+0x14/0x88 kernel/softirq.c:661 handle_domain_irq+0xf4/0x178 kernel/irq/irqdesc.c:710 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:758 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_enable arch/arm64/include/asm/irqflags.h:35 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1338 [inline] finish_lock_switch+0xc4/0x1e8 kernel/sched/core.c:4784 finish_task_switch+0x120/0x6b4 kernel/sched/core.c:4902 context_switch kernel/sched/core.c:5033 [inline] __schedule+0xf14/0x1e48 kernel/sched/core.c:6376 schedule+0x11c/0x1c8 kernel/sched/core.c:6459 freezable_schedule include/linux/freezer.h:172 [inline] do_nanosleep+0x1a4/0x668 kernel/time/hrtimer.c:2045 hrtimer_nanosleep+0x1f0/0x384 kernel/time/hrtimer.c:2098 common_nsleep+0xa8/0xc0 kernel/time/posix-timers.c:1272 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1313 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1290 [inline] __arm64_sys_clock_nanosleep+0x350/0x38c kernel/time/posix-timers.c:1290 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584