watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [aoe_tx0:2452] Modules linked in: irq event stamp: 66635103 hardirqs last enabled at (66635102): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (66635102): [] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194 hardirqs last disabled at (66635103): [] enter_from_kernel_mode+0x14/0x34 arch/arm64/kernel/entry-common.c:42 softirqs last enabled at (1170): [] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (1174): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 CPU: 1 UID: 0 PID: 2452 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : __lse_atomic_sub_return arch/arm64/include/asm/atomic_lse.h:97 [inline] pc : arch_atomic_sub_return arch/arm64/include/asm/atomic.h:53 [inline] pc : raw_atomic_sub_return include/linux/atomic/atomic-arch-fallback.h:787 [inline] pc : raw_atomic_dec_return include/linux/atomic/atomic-arch-fallback.h:1238 [inline] pc : raw_atomic_dec_and_test include/linux/atomic/atomic-arch-fallback.h:2280 [inline] pc : atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1384 [inline] pc : uart_port_deref drivers/tty/serial/serial_core.c:74 [inline] pc : uart_port_unlock_deref+0x144/0x2ec drivers/tty/serial/serial_core.c:92 lr : __lse_atomic_fetch_add arch/arm64/include/asm/atomic_lse.h:62 [inline] lr : __lse_atomic_fetch_sub arch/arm64/include/asm/atomic_lse.h:77 [inline] lr : __lse_atomic_sub_return arch/arm64/include/asm/atomic_lse.h:97 [inline] lr : arch_atomic_sub_return arch/arm64/include/asm/atomic.h:53 [inline] lr : raw_atomic_sub_return include/linux/atomic/atomic-arch-fallback.h:787 [inline] lr : raw_atomic_dec_return include/linux/atomic/atomic-arch-fallback.h:1238 [inline] lr : raw_atomic_dec_and_test include/linux/atomic/atomic-arch-fallback.h:2280 [inline] lr : atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1384 [inline] lr : uart_port_deref drivers/tty/serial/serial_core.c:74 [inline] lr : uart_port_unlock_deref+0x13c/0x2ec drivers/tty/serial/serial_core.c:92 sp : ffff8000a2f97710 x29: ffff8000a2f97720 x28: ffff0000c9208a70 x27: 0000000000000000 x26: ffff0000c9208a00 x25: ffff0000c9208ad8 x24: dfff800000000000 x23: 0000000000000003 x22: 1ffff00012edd011 x21: ffff8000911c1c80 x20: ffff0000ca668f84 x19: ffff8000976e8088 x18: 00000000ffffffff x17: ffff800093335000 x16: ffff80008052bd88 x15: 0000000000000001 x14: 1fffe000194cd1f0 x13: 0000000000000000 x12: 0000000000000000 x11: ffff6000194cd1f1 x10: 0000000000ff0100 x9 : 0000000000000000 x8 : 0000000000000002 x7 : ffff800083b334e0 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800083b33890 x2 : 0000000000000001 x1 : 0000000000000004 x0 : 0000000000000001 Call trace: __lse_atomic_fetch_add arch/arm64/include/asm/atomic_lse.h:62 [inline] (P) __lse_atomic_fetch_sub arch/arm64/include/asm/atomic_lse.h:77 [inline] (P) __lse_atomic_sub_return arch/arm64/include/asm/atomic_lse.h:97 [inline] (P) arch_atomic_sub_return arch/arm64/include/asm/atomic.h:53 [inline] (P) raw_atomic_sub_return include/linux/atomic/atomic-arch-fallback.h:787 [inline] (P) raw_atomic_dec_return include/linux/atomic/atomic-arch-fallback.h:1238 [inline] (P) raw_atomic_dec_and_test include/linux/atomic/atomic-arch-fallback.h:2280 [inline] (P) atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1384 [inline] (P) uart_port_deref drivers/tty/serial/serial_core.c:74 [inline] (P) uart_port_unlock_deref+0x144/0x2ec drivers/tty/serial/serial_core.c:92 (P) uart_write+0xc4/0x130 drivers/tty/serial/serial_core.c:626 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:5248 [inline] netdev_start_xmit include/linux/netdevice.h:5257 [inline] xmit_one net/core/dev.c:3845 [inline] dev_hard_start_xmit+0x2b0/0x890 net/core/dev.c:3861 __dev_queue_xmit+0x1600/0x32a8 net/core/dev.c:4763 dev_queue_xmit include/linux/netdevice.h:3365 [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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6533 Comm: sshd-session Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : put_cpu_partial+0x1c0/0x244 mm/slub.c:3950 lr : put_cpu_partial+0x1b4/0x244 mm/slub.c:3948 sp : ffff8000a3b07240 x29: ffff8000a3b07240 x28: 000000000000000b x27: 00000000000c000c x26: fffffdffc375f6c0 x25: ffff80008f51ad90 x24: ffff80008f5b1f28 x23: 0000000000000000 x22: ffff80008f5b1000 x21: 0000000000000000 x20: ffff00019bec2d90 x19: ffff0000c18c1dc0 x18: 00000000ffffffff x17: ffff800093335000 x16: ffff80008052bd88 x15: 0000000000000001 x14: 1fffe00018000138 x13: 0000000000000000 x12: 0000000000000000 x11: ffff800093134c88 x10: 0000000000ff0100 x9 : 0000000000000000 x8 : 00000000000000c0 x7 : ffff800080be2cd4 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : 0000000000000010 x2 : 0000000000000007 x1 : 0000000000000080 x0 : ffff80010c9a8000 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) put_cpu_partial+0x1c0/0x244 mm/slub.c:3948 (P) __slab_free+0x198/0x240 mm/slub.c:5929 do_slab_free mm/slub.c:6582 [inline] ___cache_free+0x150/0x170 mm/slub.c:6708 qlink_free+0x48/0x94 mm/kasan/quarantine.c:163 qlist_free_all+0x44/0xb8 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x118/0x124 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x2c/0x88 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_node_noprof+0x3fc/0x670 mm/slub.c:5340 kmalloc_reserve+0xc4/0x268 net/core/skbuff.c:579 __alloc_skb+0x170/0x2ec net/core/skbuff.c:670 alloc_skb_fclone include/linux/skbuff.h:1433 [inline] tcp_stream_alloc_skb+0x44/0x2c4 net/ipv4/tcp.c:912 tcp_sendmsg_locked+0xb18/0x47a8 net/ipv4/tcp.c:1218 tcp_sendmsg+0x40/0x64 net/ipv4/tcp.c:1413 inet_sendmsg+0x154/0x284 net/ipv4/af_inet.c:853 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] sock_write_iter+0x298/0x3d0 net/socket.c:1195 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x540/0xa3c fs/read_write.c:686 ksys_write+0x120/0x210 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:746 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:724 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596