watchdog: BUG: soft lockup - CPU#0 stuck for 131s! [kworker/u8:5:84] Modules linked in: irq event stamp: 4753168 hardirqs last enabled at (4753167): [] irqentry_exit+0x5dd/0x660 kernel/entry/common.c:219 hardirqs last disabled at (4753168): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (4682302): [] __local_bh_enable_ip+0x1b3/0x2e0 kernel/softirq.c:305 softirqs last disabled at (4682296): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (4682296): [] spin_lock_bh include/linux/spinlock_rt.h:87 [inline] softirqs last disabled at (4682296): [] nsim_dev_trap_report drivers/net/netdevsim/dev.c:886 [inline] softirqs last disabled at (4682296): [] nsim_dev_trap_report_work+0x72e/0xbc0 drivers/net/netdevsim/dev.c:921 CPU: 0 UID: 0 PID: 84 Comm: kworker/u8:5 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xec1/0x12b0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 f8 9d 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 33 99 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 17 99 RSP: 0018:ffffc9000154f620 EFLAGS: 00000293 RAX: ffffffff81b4c9a9 RBX: 1ffff1101712854d RCX: ffff88801b7e5ac0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000154f7a0 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1db664f R12: ffff8880b8942a68 R13: dffffc0000000000 R14: ffff8880b883c8c0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888126d03000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff81df82d58 CR3: 000000000d3a8000 CR4: 00000000003526f0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline] smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2921 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:874 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 21423 Comm: syz.6.4641 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:num_possible_cpus include/linux/cpumask.h:1222 [inline] RIP: 0010:mm_get_cid+0xab/0x130 kernel/sched/sched.h:3759 Code: 41 5c 41 5d 41 5e 41 5f 5d e9 51 e0 44 09 cc 49 c7 c5 c8 b4 01 8d 49 c1 ed 03 bd 00 00 00 80 eb 07 44 89 f0 f7 d8 71 d4 f3 90 <43> 0f b6 44 25 00 84 c0 75 41 44 8b 3d 0c 4d 6f 0b 48 89 df 4c 89 RSP: 0018:ffffc90005627968 EFLAGS: 00000887 RAX: 0000000080000000 RBX: ffff888038b07ed0 RCX: 1ffff11007828a44 RDX: 0000000000000002 RSI: 0000000000000002 RDI: ffff888038b07ed0 RBP: 0000000080000000 R08: ffff888038b07ec7 R09: 1ffff11007160fd8 R10: dffffc0000000000 R11: ffffed1007160fd9 R12: dffffc0000000000 R13: 1ffffffff1a03699 R14: 0000000080000000 R15: 0000000000000002 FS: 00007ff81dfd66c0(0000) GS:ffff888126e03000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000051aa0000 CR4: 00000000003526f0 Call Trace: mm_cid_from_cpu kernel/sched/sched.h:3820 [inline] mm_cid_schedin kernel/sched/sched.h:3870 [inline] mm_cid_switch_to kernel/sched/sched.h:3886 [inline] context_switch kernel/sched/core.c:5245 [inline] __schedule+0x2153/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 __io_cqring_wait_schedule io_uring/io_uring.c:2603 [inline] io_cqring_wait_schedule io_uring/io_uring.c:2625 [inline] io_cqring_wait io_uring/io_uring.c:2707 [inline] __do_sys_io_uring_enter io_uring/io_uring.c:3319 [inline] __se_sys_io_uring_enter+0x1e3a/0x2b00 io_uring/io_uring.c:3219 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff81fd6f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff81dfd6038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007ff81ffc5fa0 RCX: 00007ff81fd6f749 RDX: 00000000000004c1 RSI: 0000000000000627 RDI: 0000000000000005 RBP: 00007ff81fdf3f91 R08: 0000000000000000 R09: 0000000000000030 R10: 0000000000000043 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff81ffc6038 R14: 00007ff81ffc5fa0 R15: 00007ffeb2a9f438