watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [kworker/0:0:8] Modules linked in: irq event stamp: 48533 hardirqs last enabled at (48532): [] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:85 [inline] hardirqs last enabled at (48532): [] exit_to_kernel_mode+0xdc/0x10c arch/arm64/kernel/entry-common.c:95 hardirqs last disabled at (48533): [] __el1_irq arch/arm64/kernel/entry-common.c:557 [inline] hardirqs last disabled at (48533): [] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:575 softirqs last enabled at (41020): [] pppoe_flush_dev drivers/net/ppp/pppoe.c:327 [inline] softirqs last enabled at (41020): [] pppoe_device_event+0x464/0x4a0 drivers/net/ppp/pppoe.c:346 softirqs last disabled at (41024): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 CPU: 0 UID: 0 PID: 8 Comm: kworker/0:0 Not tainted 6.12.0-syzkaller-g7b1d1d4cfac0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events ser_release pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : queued_spin_lock_slowpath+0x15c/0xd00 kernel/locking/qspinlock.c:380 lr : queued_spin_lock_slowpath+0x168/0xd00 kernel/locking/qspinlock.c:380 sp : ffff800097977520 x29: ffff8000979775c0 x28: 1fffe0001ad2c420 x27: 1ffff00012f2eeb0 x26: dfff800000000000 x25: 1fffe0001833ab5a x24: ffff800097977540 x23: ffff800097977580 x22: ffff700012f2eea8 x21: 0000000000000001 x20: 0000000000000001 x19: ffff0000d6962100 x18: ffff800097977400 x17: 000000000002b14e x16: ffff800080aca118 x15: 0000000000000001 x14: 1fffe0001ad2c420 x13: 0000000000000000 x12: 0000000000000000 x11: ffff60001ad2c421 x10: 1fffe0001ad2c420 x9 : 0000000000000000 x8 : 0000000000000001 x7 : 0000000000000000 x6 : 0000000000000000 x5 : ffff800093604598 x4 : 0000000000000008 x3 : ffff80008b63a244 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+0x15c/0xd00 kernel/locking/qspinlock.c:380 (P) queued_spin_lock_slowpath+0x168/0xd00 kernel/locking/qspinlock.c:380 (L) queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x2ec/0x334 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:4371 [inline] netif_freeze_queues net/sched/sch_generic.c:460 [inline] netif_tx_lock+0x9c/0x1d8 net/sched/sch_generic.c:469 netif_tx_lock_bh include/linux/netdevice.h:4455 [inline] dev_watchdog_down net/sched/sch_generic.c:574 [inline] dev_deactivate_many+0x274/0xa8c net/sched/sch_generic.c:1369 __dev_close_many+0x270/0x3c8 net/core/dev.c:1547 dev_close_many+0x1e0/0x474 net/core/dev.c:1585 dev_close+0x174/0x250 net/core/dev.c:1611 ser_release+0x188/0x238 drivers/net/caif/caif_serial.c:309 process_one_work+0x7bc/0x1600 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x97c/0xeec kernel/workqueue.c:3391 kthread+0x288/0x310 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 2346 Comm: aoe_tx0 Not tainted 6.12.0-syzkaller-g7b1d1d4cfac0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 pstate: 80400005 (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 : ffff8000a1ac7730 x29: ffff8000a1ac7730 x28: ffff0000cdc8b0b0 x27: dfff800000000000 x26: 0000000000000000 x25: ffff800091292c00 x24: ffff0000c9228f48 x23: 0000000000000003 x22: 0000000000000000 x21: ffff800091292c00 x20: ffff80009776cde0 x19: 0000000000000000 x18: ffff8000a1ac73e0 x17: 000000000002b0e8 x16: ffff800080355c58 x15: 0000000000000001 x14: 1ffff00012eed9bc x13: ffff8000a1ac8000 x12: 0000000000000003 x11: 0000000000000202 x10: 0000000000000003 x9 : 0000000000000000 x8 : 00000000000000c0 x7 : ffff800083ec1ff0 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000002 x1 : ffff80008b6c4000 x0 : ffff800123e21000 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) __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] (L) _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194 (L) spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:782 [inline] uart_write+0x4b0/0x9b4 drivers/tty/serial/serial_core.c:628 handle_tx+0x200/0x604 drivers/net/caif/caif_serial.c:236 caif_xmit+0x108/0x150 drivers/net/caif/caif_serial.c:282 __netdev_start_xmit include/linux/netdevice.h:4928 [inline] netdev_start_xmit include/linux/netdevice.h:4937 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x260/0x904 net/core/dev.c:3604 __dev_queue_xmit+0x1638/0x3548 net/core/dev.c:4432 dev_queue_xmit include/linux/netdevice.h:3094 [inline] tx+0x9c/0x1cc drivers/block/aoe/aoenet.c:62 kthread+0x1ac/0x374 drivers/block/aoe/aoecmd.c:1237 kthread+0x288/0x310 kernel/kthread.c:389 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862