watchdog: BUG: soft lockup - CPU#0 stuck for 25s! [syz.0.459:7115] Modules linked in: irq event stamp: 69738 hardirqs last enabled at (69737): [] raw_spin_rq_unlock_irq kernel/sched/sched.h:1673 [inline] hardirqs last enabled at (69737): [] finish_lock_switch kernel/sched/core.c:5241 [inline] hardirqs last enabled at (69737): [] finish_task_switch+0x234/0x858 kernel/sched/core.c:5359 hardirqs last disabled at (69738): [] __el1_irq arch/arm64/kernel/entry-common.c:527 [inline] hardirqs last disabled at (69738): [] el1_interrupt+0x28/0x60 arch/arm64/kernel/entry-common.c:543 softirqs last enabled at (69726): [] softirq_handle_end kernel/softirq.c:468 [inline] softirqs last enabled at (69726): [] handle_softirqs+0xc28/0xd98 kernel/softirq.c:650 softirqs last disabled at (69721): [] __do_softirq+0x14/0x20 kernel/softirq.c:656 CPU: 0 UID: 0 PID: 7115 Comm: syz.0.459 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : finish_task_switch+0x23c/0x858 kernel/sched/core.c:5361 lr : raw_spin_rq_unlock_irq kernel/sched/sched.h:1673 [inline] lr : finish_lock_switch kernel/sched/core.c:5241 [inline] lr : finish_task_switch+0x234/0x858 kernel/sched/core.c:5359 sp : ffff8000933071b0 x29: ffff8000933071c0 x28: ffff0000c58e9d40 x27: 1fffe00034bba0b4 x26: ffff0001a5dd05a0 x25: 0000000000000000 x24: dfff800000000000 x23: ffff0001a5dcf760 x22: ffff0001a5dcf740 x21: ffff0000c58e9d40 x20: 0000000000000000 x19: ffff0000f4e48000 x18: 1fffe00034bb7428 x17: 0000000000000003 x16: ffff800088b37000 x15: 000000002005b640 x14: ffff0001a5dba14c x13: 0000000000000001 x12: 0000000000000000 x11: ffff800080156074 x10: 0000000000000003 x9 : 0000000000000000 x8 : 0000000000001670 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000008 x3 : ffff80008015611c x2 : 0000000000000000 x1 : ffff0000c58e9d40 x0 : ffff80011d2d8000 Call trace: __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline] (P) arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] (P) raw_spin_rq_unlock_irq kernel/sched/sched.h:1673 [inline] (P) finish_lock_switch kernel/sched/core.c:5241 [inline] (P) finish_task_switch+0x23c/0x858 kernel/sched/core.c:5359 (P) context_switch kernel/sched/core.c:5513 [inline] __schedule+0x1374/0x2d80 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x13c/0x20c kernel/sched/core.c:7326 schedule_timeout+0xc0/0x28c kernel/time/sleep_timeout.c:75 unix_wait_for_peer+0x188/0x264 net/unix/af_unix.c:1621 unix_dgram_sendmsg+0xa3c/0x1078 net/unix/af_unix.c:2257 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg+0xc8/0x17c net/socket.c:790 ____sys_sendmsg+0x3f8/0x6c8 net/socket.c:2684 ___sys_sendmsg+0x198/0x224 net/socket.c:2738 __sys_sendmmsg+0x204/0x580 net/socket.c:2827 __do_sys_sendmmsg net/socket.c:2854 [inline] __se_sys_sendmmsg net/socket.c:2851 [inline] __arm64_sys_sendmmsg+0xac/0xc8 net/socket.c:2851 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 4703 Comm: udevd Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : csd_lock_wait kernel/smp.c:342 [inline] pc : smp_call_function_many_cond+0x114c/0x17c0 kernel/smp.c:912 lr : csd_lock_wait kernel/smp.c:342 [inline] lr : smp_call_function_many_cond+0x1164/0x17c0 kernel/smp.c:912 sp : ffff800097147900 x29: ffff800097147a20 x28: 0000000000000011 x27: 0000000000000000 x26: ffff0001a5df5980 x25: ffff800088b3b6a0 x24: ffffffffffffffff x23: dfff800000000000 x22: 1fffe00034bbeb30 x21: 1fffe00034bbeb31 x20: ffff0001a5df5988 x19: ffff0001a5dd6e08 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000 x11: 0000000000000000 x10: ffff600034bbadc2 x9 : 0000000000000000 x8 : 0000000000000011 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000008 x3 : ffff8000805b6d24 x2 : 0000000000000000 x1 : ffff0000db623a80 x0 : 0000000000000000 Call trace: __cmpwait_case_32 arch/arm64/include/asm/cmpxchg.h:233 [inline] (P) __cmpwait arch/arm64/include/asm/cmpxchg.h:259 [inline] (P) csd_lock_wait kernel/smp.c:342 [inline] (P) smp_call_function_many_cond+0x114c/0x17c0 kernel/smp.c:912 (P) on_each_cpu_cond_mask+0x5c/0xc4 kernel/smp.c:1077 on_each_cpu_cond include/linux/smp.h:106 [inline] invalidate_bh_lrus+0x34/0x40 fs/buffer.c:1538 kill_bdev+0x68/0x90 block/bdev.c:90 blkdev_flush_mapping+0xb8/0x24c block/bdev.c:715 blkdev_put_whole+0x64/0x110 block/bdev.c:722 bdev_release+0x244/0x328 block/bdev.c:-1 blkdev_release+0x20/0x34 block/fops.c:680 __fput+0x338/0x74c fs/file_table.c:512 fput_close_sync+0x10c/0x278 fs/file_table.c:617 __do_sys_close fs/open.c:1511 [inline] __se_sys_close fs/open.c:1496 [inline] __arm64_sys_close+0x80/0x110 fs/open.c:1496 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590