watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [syz.5.2857:18917] Modules linked in: irq event stamp: 14054759 hardirqs last enabled at (14054758): [] irqentry_exit+0x59e/0x620 kernel/entry/common.c:242 hardirqs last disabled at (14054759): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (5764060): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (5764060): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (5764060): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 softirqs last disabled at (5764063): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (5764063): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (5764063): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 18917 Comm: syz.5.2857 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_preemption_disabled+0xd/0xe0 lib/smp_processor_id.c:16 Code: 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 65 8b 05 57 73 6d 07 <65> 8b 0d 4c 73 6d 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d c3 RSP: 0000:ffffc90000006d38 EFLAGS: 00000203 RAX: 0000000000000000 RBX: ffffffff931cf190 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8c27c9e0 RDI: ffffffff8c27c9a0 RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000 R10: ffffc90000006a08 R11: ffffffff81b0c390 R12: 0000000000000002 R13: ffffffff8e75e5e0 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fecf18226c0(0000) GS:ffff88812545a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9792b0c000 CR3: 0000000024ea8000 CR4: 00000000003526f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:752 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x57/0x2e0 kernel/locking/lockdep.c:5831 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5260 [inline] __kmalloc_noprof+0x35c/0x760 mm/slub.c:5272 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] cfg80211_inform_single_bss_data+0x952/0x1b70 net/wireless/scan.c:2344 cfg80211_inform_bss_data+0x266/0x3c40 net/wireless/scan.c:3226 cfg80211_inform_bss_frame_data+0x3c7/0x760 net/wireless/scan.c:3317 ieee80211_bss_info_update+0x794/0xa40 net/mac80211/scan.c:230 ieee80211_scan_rx+0x552/0xa40 net/mac80211/scan.c:364 __ieee80211_rx_handle_packet net/mac80211/rx.c:5305 [inline] ieee80211_rx_list+0x29e5/0x3710 net/mac80211/rx.c:5588 ieee80211_rx_napi+0x1b1/0x3e0 net/mac80211/rx.c:5611 ieee80211_rx include/net/mac80211.h:5267 [inline] ieee80211_handle_queued_frames+0xe8/0x1e0 net/mac80211/main.c:452 tasklet_action_common+0x2da/0x4b0 kernel/softirq.c:925 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:arch_atomic64_read arch/x86/include/asm/atomic64_64.h:15 [inline] RIP: 0010:raw_atomic64_read include/linux/atomic/atomic-arch-fallback.h:2583 [inline] RIP: 0010:raw_atomic_long_read include/linux/atomic/atomic-long.h:38 [inline] RIP: 0010:atomic_long_read include/linux/atomic/atomic-instrumented.h:3189 [inline] RIP: 0010:__mutex_owner kernel/locking/mutex.h:47 [inline] RIP: 0010:mutex_can_spin_on_owner kernel/locking/mutex.c:411 [inline] RIP: 0010:mutex_optimistic_spin kernel/locking/mutex.c:456 [inline] RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:618 [inline] RIP: 0010:__mutex_lock+0x268/0x1300 kernel/locking/mutex.c:776 Code: e4 0f 84 81 00 00 00 4c 89 e7 be 08 00 00 00 e8 be c2 7f f6 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 38 c0 7f f6 <4d> 8b 3c 24 49 83 e7 f8 74 54 4c 89 e9 4d 8d 6f 34 4c 89 e8 48 c1 RSP: 0000:ffffc90003f77380 EFLAGS: 00000246 RAX: 1ffffffff1f79d5c RBX: 0000000000000000 RCX: ffffffff8bb046a2 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fbceae0 RBP: ffffc90003f77530 R08: ffffffff8fbceae7 R09: 1ffffffff1f79d5c R10: dffffc0000000000 R11: fffffbfff1f79d5d R12: ffffffff8fbceae0 R13: dffffc0000000000 R14: ffff888050528000 R15: 0000000000000000 rtnl_lock net/core/rtnetlink.c:80 [inline] rtnetlink_rcv_msg+0x722/0xbe0 net/core/rtnetlink.c:6964 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0x972/0x9f0 net/socket.c:2592 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fecf099c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fecf1822028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fecf0c15fa0 RCX: 00007fecf099c799 RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 000000000000000d RBP: 00007fecf0a32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fecf0c16038 R14: 00007fecf0c15fa0 R15: 00007fff00ffbf38 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12801 Comm: kworker/u8:35 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x17/0x70 kernel/kcov.c:217 Code: cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d c8 bd 56 11 65 8b 15 e9 bd 56 11 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 a4 16 00 00 RSP: 0018:ffffc90000a07cd8 EFLAGS: 00000046 RAX: ffffffff81f8f649 RBX: 1ffff11006619bac RCX: ffff8880792b1e80 RDX: 0000000080010103 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a07df0 R08: ffff8880330cdca7 R09: 1ffff11006619b94 R10: dffffc0000000000 R11: ffffed1006619b95 R12: 0000000000000000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880330cdca4 FS: 0000000000000000(0000) GS:ffff88812555a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000542be000 CR4: 00000000003526f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __perf_event_overflow+0x5d9/0xec0 kernel/events/core.c:10710 perf_event_overflow kernel/events/core.c:10784 [inline] perf_swevent_hrtimer+0x481/0x650 kernel/events/core.c:12195 __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x4e7/0xcc0 kernel/time/hrtimer.c:1849 hrtimer_interrupt+0x42b/0x1010 kernel/time/hrtimer.c:1911 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x102/0x460 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__srcu_check_read_flavor+0x17/0x250 kernel/rcu/srcutree.c:793 Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 10 89 f3 49 89 fe <83> fe 02 74 17 83 fb 04 74 12 65 8b 05 78 27 72 11 a9 00 00 f0 00 RSP: 0018:ffffc90000a083d8 EFLAGS: 00000286 RAX: ffffffff8e7be4bf RBX: 0000000000000004 RCX: 0000000080000104 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8e7bd4c0 RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000 R10: ffffc90000a085b8 R11: ffffffff81b0c390 R12: 0000000000000002 R13: ffffffff8e75e5e0 R14: ffffffff8e7bd4c0 R15: 0000000000000000 srcu_check_read_flavor include/linux/srcutree.h:373 [inline] srcu_read_unlock_fast_notrace include/linux/srcu.h:530 [inline] class_srcu_fast_notrace_destructor include/linux/srcu.h:634 [inline] __do_trace_lock_acquire include/trace/events/lock.h:24 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x2cc/0x2e0 kernel/locking/lockdep.c:5831 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4538 [inline] slab_alloc_node mm/slub.c:4866 [inline] kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4918 __alloc_skb+0x1d0/0x7d0 net/core/skbuff.c:702 skb_copy+0x188/0x800 net/core/skbuff.c:2195 mac80211_hwsim_tx_frame_no_nl+0xd00/0x11f0 drivers/net/wireless/virtual/mac80211_hwsim.c:1891 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2264 mac80211_hwsim_beacon_tx+0x3e8/0x870 drivers/net/wireless/virtual/mac80211_hwsim.c:2365 __iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:760 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:796 mac80211_hwsim_beacon+0xbb/0x180 drivers/net/wireless/virtual/mac80211_hwsim.c:2395 __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x53a/0xcc0 kernel/time/hrtimer.c:1849 hrtimer_run_softirq+0x182/0x5a0 kernel/time/hrtimer.c:1866 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:strlen+0x1f/0x70 lib/string.c:420 Code: 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 54 53 48 c7 c0 ff ff ff ff 49 be 00 00 00 00 00 fc ff df 48 89 fb <49> 89 c7 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 11 48 ff c3 RSP: 0018:ffffc90004def298 EFLAGS: 00000206 RAX: 0000000000000004 RBX: ffffffff8bce01a5 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8e75e5e0 RDI: ffffffff8bce01a0 RBP: ffffc90004def3c0 R08: 0000000000000002 R09: 0000000000000000 R10: ffffc90004def578 R11: ffffffff81b0c390 R12: ffffffff8e62a540 R13: ffffffff8e75e5e0 R14: dffffc0000000000 R15: 0000000000000003 __fortify_strlen include/linux/fortify-string.h:266 [inline] trace_event_get_offsets_lock_acquire include/trace/events/lock.h:24 [inline] do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline] perf_trace_lock_acquire+0xde/0x440 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+0x2a4/0x2e0 kernel/locking/lockdep.c:5831 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2685 [inline] slab_free mm/slub.c:6165 [inline] kfree+0x1c1/0x630 mm/slub.c:6483 skb_kfree_head net/core/skbuff.c:1089 [inline] skb_free_head net/core/skbuff.c:1101 [inline] skb_release_data+0x6f0/0x940 net/core/skbuff.c:1128 skb_release_all net/core/skbuff.c:1203 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1217 nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:922 process_one_work kernel/workqueue.c:3276 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245