watchdog: BUG: soft lockup - CPU#0 stuck for 138s! [syz.2.18:5993] Modules linked in: irq event stamp: 19579073 hardirqs last enabled at (19579072): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:214 hardirqs last disabled at (19579073): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1052 softirqs last enabled at (6926918): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (6926918): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (6926918): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 softirqs last disabled at (6926921): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (6926921): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (6926921): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 5993 Comm: syz.2.18 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 2b 2a d1 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc90000006b18 EFLAGS: 00000206 RAX: 09a76e9367c6bc00 RBX: 0000000000000000 RCX: 09a76e9367c6bc00 RDX: 0000000000000000 RSI: ffffffff8d8f5ddc RDI: ffffffff8bbf0e60 RBP: ffffffff81738c45 R08: 0000000000000000 R09: ffffffff81738c45 R10: ffffc90000006788 R11: fffff52000000cf3 R12: 0000000000000002 R13: ffffffff8df3d6e0 R14: 0000000000000000 R15: 0000000000000246 FS: 00007fadb2d4f6c0(0000) GS:ffff888126138000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9b59ef317a CR3: 0000000078560000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2543 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x19a/0x6d0 mm/slub.c:6849 ieee80211_inform_bss+0xbd9/0x10a0 net/mac80211/scan.c:160 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline] cfg80211_inform_single_bss_data+0xd05/0x1ac0 net/wireless/scan.c:2385 cfg80211_inform_bss_data+0x203/0x3b40 net/wireless/scan.c:3240 cfg80211_inform_bss_frame_data+0x3d7/0x730 net/wireless/scan.c:3331 ieee80211_bss_info_update+0x749/0x9e0 net/mac80211/scan.c:226 ieee80211_scan_rx+0x593/0xa20 net/mac80211/scan.c:355 __ieee80211_rx_handle_packet net/mac80211/rx.c:5194 [inline] ieee80211_rx_list+0x2192/0x2c10 net/mac80211/rx.c:5451 ieee80211_rx_napi+0x1a8/0x3d0 net/mac80211/rx.c:5474 ieee80211_rx include/net/mac80211.h:5214 [inline] ieee80211_handle_queued_frames+0xe8/0x1f0 net/mac80211/main.c:453 tasklet_action_common+0x36c/0x580 kernel/softirq.c:925 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__asan_memset+0x29/0x50 mm/kasan/shadow.c:87 Code: 90 f3 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 7e e4 ff ff 84 c0 74 11 4c 89 f7 <89> ee 48 89 da 5b 41 5e 5d e9 09 e8 20 09 31 c0 5b 41 5e 5d e9 4e RSP: 0018:ffffc900053dee20 EFLAGS: 00000202 RAX: ffffffff81f12401 RBX: 0000000000000010 RCX: ffffffff81f12446 RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc900053deec8 RBP: 0000000000000000 R08: ffffc900053deed7 R09: 1ffff92000a7bdda R10: dffffc0000000000 R11: fffff52000a7bddb R12: ffff8880275ce400 R13: ffffc900053deec8 R14: ffffc900053deec8 R15: dffffc0000000000 perf_sample_data_init include/linux/perf_event.h:1358 [inline] perf_tp_event+0x276/0x1380 kernel/events/core.c:11010 perf_trace_run_bpf_submit+0xee/0x170 kernel/events/core.c:10936 do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline] perf_trace_lock_acquire+0x335/0x410 include/trace/events/lock.h:24 __do_trace_lock_acquire include/trace/events/lock.h:24 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x311/0x360 kernel/locking/lockdep.c:5831 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2543 [inline] slab_free mm/slub.c:6642 [inline] kmem_cache_free+0x19b/0x690 mm/slub.c:6752 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x837/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fadb1f8f6c9 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:00007fadb2d4f038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fadb21e5fa0 RCX: 00007fadb1f8f6c9 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 000000000000000e RBP: 00007fadb2011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fadb21e6038 R14: 00007fadb21e5fa0 R15: 00007ffde1e72ba8 Sending NMI from CPU 0 to CPUs 1: rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6041 Comm: kworker/u8:14 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:__sanitizer_cov_trace_switch+0x19/0x130 kernel/kcov.c:334 Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 06 48 8b 4e 08 48 83 c1 f8 48 c1 c1 3d 48 83 f9 02 7f 1e <48> 85 c9 74 3c 48 83 f9 01 0f 85 f4 00 00 00 b9 03 00 00 00 48 85 RSP: 0018:ffffc90000a08048 EFLAGS: 00000093 RAX: 0000000000000002 RBX: 0000000000000025 RCX: 0000000000000000 RDX: ffffffff8b42eb7f RSI: ffffffff8f642010 RDI: 0000000000000025 RBP: ffffffff8b6b93a2 R08: ffff888025060000 R09: 0000000000000002 R10: 0000000000000003 R11: 0000000000010000 R12: ffffffff8b6b93a2 R13: ffffc90000a080f8 R14: 0000000000000000 R15: ffffffff8b6b93a2 FS: 0000000000000000(0000) GS:ffff888126238000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f998d610201 CR3: 000000000dd38000 CR4: 00000000003526f0 Call Trace: format_decode+0x84/0xe30 lib/vsprintf.c:2671 vsnprintf+0x102/0xf00 lib/vsprintf.c:2869 snprintf+0xda/0x120 lib/vsprintf.c:3020 print_caller kernel/printk/printk.c:1363 [inline] info_print_prefix+0x1e1/0x310 kernel/printk/printk.c:1382 record_print_text+0x154/0x420 kernel/printk/printk.c:1429 printk_get_next_message+0x26d/0x7b0 kernel/printk/printk.c:2997 console_emit_next_record kernel/printk/printk.c:3065 [inline] console_flush_all+0x4ca/0xb10 kernel/printk/printk.c:3199 __console_flush_and_unlock kernel/printk/printk.c:3258 [inline] console_unlock+0xbb/0x190 kernel/printk/printk.c:3298 vprintk_emit+0x4c5/0x590 kernel/printk/printk.c:2423 _printk+0xcf/0x120 kernel/printk/printk.c:2448 print_other_cpu_stall+0x189/0x1340 kernel/rcu/tree_stall.h:656 check_cpu_stall kernel/rcu/tree_stall.h:857 [inline] rcu_pending kernel/rcu/tree.c:3671 [inline] rcu_sched_clock_irq+0xa47/0x11b0 kernel/rcu/tree.c:2706 update_process_times+0x23c/0x2f0 kernel/time/timer.c:2473 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x39a/0x520 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x4e0/0xc60 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd44/0x12d0 kernel/smp.c:877 Code: 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 6f 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 45 6f 0b 00 eb e4 44 89 e1 80 e1 07 80 c1 03 38 c1 7c e2 RSP: 0018:ffffc9000555f640 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 1ffff11017108431 RCX: ffff888025060000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000555f7c0 R08: ffffffff8f7cee77 R09: 1ffffffff1ef9dce R10: dffffc0000000000 R11: fffffbfff1ef9dcf R12: ffff8880b8842188 R13: dffffc0000000000 R14: ffff8880b893b1c0 R15: 0000000000000000 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:2713 [inline] smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2923 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:852 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245