watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:2:3924] Modules linked in: irq event stamp: 292075 hardirqs last enabled at (292074): [] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:86 [inline] hardirqs last enabled at (292074): [] exit_to_kernel_mode+0xc0/0xf0 arch/arm64/kernel/entry-common.c:96 hardirqs last disabled at (292075): [] __el1_irq arch/arm64/kernel/entry-common.c:650 [inline] hardirqs last disabled at (292075): [] el1_interrupt+0x24/0x54 arch/arm64/kernel/entry-common.c:668 softirqs last enabled at (287934): [] pppoe_flush_dev drivers/net/ppp/pppoe.c:327 [inline] softirqs last enabled at (287934): [] pppoe_device_event+0x494/0x4c4 drivers/net/ppp/pppoe.c:346 softirqs last disabled at (287936): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 CPU: 0 UID: 0 PID: 3924 Comm: kworker/0:2 Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 Workqueue: events ser_release pstate: 03400005 (nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : queued_spin_lock_slowpath+0x138/0xaec kernel/locking/qspinlock.c:197 lr : queued_spin_lock_slowpath+0x144/0xaec kernel/locking/qspinlock.c:197 sp : ffff80009f6e7440 x29: ffff80009f6e74e0 x28: 1fffe00018b0bc29 x27: 1fffe0001a300002 x26: ffff0000d1800000 x25: dfff800000000000 x24: ffff700013edce8c x23: 0000000000000001 x22: ffff0000d1800010 x21: ffff0000c585e148 x20: ffff0000c585e150 x19: ffff0000c585e140 x18: 1fffe0003379be88 x17: ffff80008f7be000 x16: ffff8000805354d8 x15: 0000000000000001 x14: 1fffe00018b0bc28 x13: 0000000000000000 x12: 0000000000000000 x11: ffff600018b0bc29 x10: dfff800000000000 x9 : 0000000000000000 x8 : 0000000000000001 x7 : ffff8000894fa224 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008b029af8 x2 : 0000000000000000 x1 : 0000000000000001 x0 : 0000000000000001 Call trace: __cmpwait_case_8 arch/arm64/include/asm/cmpxchg.h:229 [inline] (P) __cmpwait arch/arm64/include/asm/cmpxchg.h:257 [inline] (P) queued_spin_lock_slowpath+0x138/0xaec kernel/locking/qspinlock.c:197 (P) queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x2a8/0x2cc kernel/locking/spinlock_debug.c:116 __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline] _raw_spin_lock+0x50/0x60 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] __netif_tx_lock include/linux/netdevice.h:4656 [inline] netif_freeze_queues net/sched/sch_generic.c:461 [inline] netif_tx_lock+0x9c/0x1d8 net/sched/sch_generic.c:470 netif_tx_lock_bh include/linux/netdevice.h:4741 [inline] netdev_watchdog_down net/sched/sch_generic.c:570 [inline] dev_deactivate_many+0x274/0xabc net/sched/sch_generic.c:1370 __dev_close_many+0x238/0x704 net/core/dev.c:1739 netif_close_many+0x1e8/0x448 net/core/dev.c:1780 netif_close+0x148/0x1f8 net/core/dev.c:1797 dev_close+0xf8/0x1e4 net/core/dev_api.c:220 ser_release+0x150/0x1ec drivers/net/caif/caif_serial.c:295 process_one_work+0x7e8/0x155c kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3400 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 2413 Comm: aoe_tx0 Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] pc : _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194 lr : __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] lr : _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194 sp : ffff8000a1c076d0 x29: ffff8000a1c076d0 x28: ffff0000f7053930 x27: 0000000000000000 x26: ffff0000f70538c0 x25: ffff0000f7053998 x24: dfff800000000000 x23: 0000000000000003 x22: 0000000000000000 x21: ffff800091382c40 x20: ffff800097897d40 x19: 0000000000000000 x18: 1fffe000337a0688 x17: ffff800093507000 x16: ffff8000805293e8 x15: 0000000000000001 x14: 1ffff00012f12fa8 x13: 0000000000000000 x12: 0000000000000000 x11: ffff800093306be8 x10: 0000000000000003 x9 : 0000000000000000 x8 : 00000000000000c0 x7 : ffff800083e11828 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000010 x2 : 0000000000000002 x1 : ffff80008edc258c x0 : ffff80010c5fd000 Call trace: __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline] (P) arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline] (P) __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] (P) _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194 (P) spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:788 [inline] uart_port_unlock_deref+0x108/0x2ec drivers/tty/serial/serial_core.c:91 uart_write+0xc4/0x130 drivers/tty/serial/serial_core.c:629 handle_tx+0x200/0x5fc drivers/net/caif/caif_serial.c:222 caif_xmit+0x108/0x150 drivers/net/caif/caif_serial.c:268 __netdev_start_xmit include/linux/netdevice.h:5219 [inline] netdev_start_xmit include/linux/netdevice.h:5228 [inline] xmit_one net/core/dev.c:3827 [inline] dev_hard_start_xmit+0x2b0/0x890 net/core/dev.c:3843 __dev_queue_xmit+0x1600/0x32a8 net/core/dev.c:4713 dev_queue_xmit include/linux/netdevice.h:3358 [inline] tx+0x9c/0x1cc drivers/block/aoe/aoenet.c:62 kthread+0x164/0x354 drivers/block/aoe/aoecmd.c:1241 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844