watchdog: BUG: soft lockup - CPU#0 stuck for 111s! [syz.8.3440:21531] Modules linked in: irq event stamp: 7620853 hardirqs last enabled at (7620852): [] irqentry_exit+0x59e/0x620 kernel/entry/common.c:242 hardirqs last disabled at (7620853): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (2261444): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (2261444): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (2261444): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 softirqs last disabled at (2261447): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (2261447): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (2261447): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 21531 Comm: syz.8.3440 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872 Code: e9 30 ff ff ff e8 45 25 0d 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 c1 a2 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d fe 78 73 RSP: 0018:ffffc90000006940 EFLAGS: 00000292 RAX: c71c7880c3d89a00 RBX: 0000000000000246 RCX: 0000000000000306 RDX: 0000000026b28eb2 RSI: ffffffff8e1699c5 RDI: ffffffff8c27c900 RBP: 0000000000000000 R08: ffffffff81d165d2 R09: ffffffff8e75e5e0 R10: dffffc0000000000 R11: fffff91ffff45e05 R12: 0000000000000002 R13: ffffffff8e75e5e0 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f905ac906c0(0000) GS:ffff88812545d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd080a4db0 CR3: 000000008232e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] trace_call_bpf+0xe3/0xb70 kernel/trace/bpf_trace.c:-1 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:11329 do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0x32d/0x410 include/trace/events/lock.h:50 __do_trace_lock_release include/trace/events/lock.h:69 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x392/0x3d0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:322 [inline] rcu_read_unlock include/linux/rcupdate.h:881 [inline] class_rcu_destructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3131 [inline] call_rcu+0xee/0x890 kernel/rcu/tree.c:3251 refdst_drop include/net/dst.h:272 [inline] skb_dst_drop include/net/dst.h:284 [inline] skb_release_head_state+0x71/0x360 net/core/skbuff.c:1177 skb_release_all net/core/skbuff.c:1201 [inline] __kfree_skb+0x24/0x210 net/core/skbuff.c:1217 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ip6gre_tunnel_xmit+0xb74/0xf70 net/ipv6/ip6_gre.c:912 __netdev_start_xmit include/linux/netdevice.h:5325 [inline] netdev_start_xmit include/linux/netdevice.h:5334 [inline] xmit_one net/core/dev.c:3871 [inline] dev_hard_start_xmit+0x2d8/0x870 net/core/dev.c:3887 sch_direct_xmit+0x251/0x4c0 net/sched/sch_generic.c:347 __dev_xmit_skb net/core/dev.c:4186 [inline] __dev_queue_xmit+0x1550/0x3890 net/core/dev.c:4802 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip6_output+0x340/0x550 net/ipv6/ip6_output.c:246 dst_output include/net/dst.h:470 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] ndisc_send_skb+0xd0b/0x1670 net/ipv6/ndisc.c:512 ndisc_send_ns net/ipv6/ndisc.c:670 [inline] ndisc_solicit+0x374/0x670 net/ipv6/ndisc.c:761 neigh_probe net/core/neighbour.c:1097 [inline] neigh_timer_handler+0xb50/0x11e0 net/core/neighbour.c:1192 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2373 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385 run_timer_base kernel/time/timer.c:2394 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404 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:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872 Code: e9 30 ff ff ff e8 45 25 0d 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 c1 a2 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d fe 78 73 RSP: 0018:ffffc900054eef60 EFLAGS: 00000296 RAX: c71c7880c3d89a00 RBX: 0000000000000246 RCX: 0000000080000004 RDX: 00000000fccf57e6 RSI: ffffffff8e1699c5 RDI: ffffffff8c27c900 RBP: 0000000000000000 R08: ffffffff81d165d2 R09: ffffffff8e75e5e0 R10: 6f6c5f646165725f R11: 64656863735f6b63 R12: 0000000000000002 R13: ffffffff8e75e5e0 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] trace_call_bpf+0xe3/0xb70 kernel/trace/bpf_trace.c:-1 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:11329 do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0x32d/0x410 include/trace/events/lock.h:50 __do_trace_lock_release include/trace/events/lock.h:69 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x392/0x3d0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:322 [inline] rcu_read_unlock_sched include/linux/rcupdate.h:972 [inline] pfn_valid+0x3b2/0x480 include/linux/mmzone.h:2207 page_table_check_set+0x25/0x610 mm/page_table_check.c:105 page_table_check_ptes_set include/linux/page_table_check.h:83 [inline] set_ptes include/linux/pgtable.h:413 [inline] __copy_present_ptes mm/memory.c:1115 [inline] copy_present_ptes mm/memory.c:1194 [inline] copy_pte_range mm/memory.c:1317 [inline] copy_pmd_range+0x4f5a/0x8050 mm/memory.c:1405 copy_pud_range mm/memory.c:1442 [inline] copy_p4d_range mm/memory.c:1466 [inline] copy_page_range+0xbe8/0x11f0 mm/memory.c:1552 dup_mmap+0xf40/0x1d90 mm/mmap.c:1841 dup_mm kernel/fork.c:1531 [inline] copy_mm+0x13b/0x4a0 kernel/fork.c:1583 copy_process+0x18b6/0x3cd0 kernel/fork.c:2223 kernel_clone+0x248/0x8e0 kernel/fork.c:2653 __do_sys_clone kernel/fork.c:2794 [inline] __se_sys_clone kernel/fork.c:2778 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2778 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: 0033:0x7f9059d9c799 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:00007f905ac8ffd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f905a015fa0 RCX: 00007f9059d9c799 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f9059e32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f905a016038 R14: 00007f905a015fa0 R15: 00007ffd23bdc748 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5195 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:rb_next+0x0/0xe0 lib/rbtree.c:464 Code: c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df RSP: 0018:ffffc90000a08d00 EFLAGS: 00000006 RAX: ffffffff8baa8502 RBX: ffff8880b8728350 RCX: ffff8880576f1e80 RDX: 0000000000010000 RSI: ffff8880b8728c28 RDI: ffff8880b8728c28 RBP: 1ffff110170e5185 R08: ffffffff9a4eace3 R09: 1ffffffff349d59c R10: dffffc0000000000 R11: fffffbfff349d59d R12: ffff8880b8728358 R13: dffffc0000000000 R14: ffff8880b8728c28 R15: 1ffff110170e506b FS: 00007fb4fa389880(0000) GS:ffff88812555d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6bed8847e8 CR3: 00000000577f4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rb_erase_cached include/linux/rbtree.h:152 [inline] timerqueue_del+0x8a/0x100 lib/timerqueue.c:57 __remove_hrtimer kernel/time/hrtimer.c:1122 [inline] __run_hrtimer kernel/time/hrtimer.c:1765 [inline] __hrtimer_run_queues+0x37b/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+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478 Code: 0f 84 44 ff ff ff e8 d2 2d 21 00 fb eb 44 e8 ca 2d 21 00 e8 25 3e 0a 0a 4d 85 f6 74 94 e8 bb 2d 21 00 fb 48 c7 c7 20 0a 75 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 16 RSP: 0018:ffffc9000213f8a0 EFLAGS: 00000293 RAX: ffffffff81a47475 RBX: ffffffff81a472ef RCX: ffff8880576f1e80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e750a20 RBP: ffffc9000213f950 R08: ffffffff9011b2b7 R09: 1ffffffff2023656 R10: dffffc0000000000 R11: fffffbfff2023657 R12: 0000000000000000 R13: 0000000000000048 R14: 0000000000000200 R15: 1ffff92000427f18 devkmsg_emit+0xe4/0x140 kernel/printk/printk.c:733 devkmsg_write+0x31c/0x400 kernel/printk/printk.c:796 do_iter_readv_writev+0x619/0x8c0 fs/read_write.c:-1 vfs_writev+0x33c/0x990 fs/read_write.c:1059 do_writev+0x154/0x2e0 fs/read_write.c:1105 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: 0033:0x7fb4f9ca7407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fff3d9c5790 EFLAGS: 00000202 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007fb4fa389880 RCX: 00007fb4f9ca7407 RDX: 0000000000000005 RSI: 00007fff3d9c5850 RDI: 0000000000000005 RBP: 00007fff3d9c5980 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff3d9c5850 R13: 00007fff3d9c58e0 R14: 0000000000000000 R15: 00007fff3d9c58c0