watchdog: BUG: soft lockup - CPU#0 stuck for 144s! [syz.9.5677:1939] Modules linked in: irq event stamp: 13196951 hardirqs last enabled at (13196950): [] irqentry_exit+0x59c/0x620 kernel/entry/common.c:219 hardirqs last disabled at (13196951): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (109636): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (109636): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (109636): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 softirqs last disabled at (109639): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (109639): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (109639): [] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 1939 Comm: syz.9.5677 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:rcu_read_unlock_special+0x1d/0x420 kernel/rcu/tree_plugin.h:770 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 10 65 8b 2d 8b 75 26 11 f7 c5 00 00 f0 00 74 14 <48> 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 49 89 RSP: 0018:ffffc90000007240 EFLAGS: 00000206 RAX: 0000000000000012 RBX: 0000000000000246 RCX: 0000000000000101 RDX: 0000000000000002 RSI: ffffffff8dacf9d6 RDI: ffffffff8be73880 RBP: ffff888125928000 R08: ffffffff8fced977 R09: 1ffffffff1f9db2e R10: dffffc0000000000 R11: fffffbfff1f9db2f R12: ffffffff8e360578 R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b863b8e8 FS: 00007f26330936c0(0000) GS:ffff888125928000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f544e263ff8 CR3: 0000000035772000 CR4: 00000000003526f0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __rcu_read_unlock+0x83/0xe0 kernel/rcu/tree_plugin.h:438 rcu_read_unlock include/linux/rcupdate.h:899 [inline] class_rcu_destructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0x1aaf/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 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:4953 [inline] kmem_cache_alloc_bulk_noprof+0x45d/0x710 mm/slub.c:7525 napi_skb_cache_get+0x41e/0x780 net/core/skbuff.c:291 __alloc_skb+0x152/0x390 net/core/skbuff.c:668 napi_alloc_skb+0x84/0x7c0 net/core/skbuff.c:832 page_to_skb+0x2ce/0x870 drivers/net/virtio_net.c:887 receive_mergeable drivers/net/virtio_net.c:2497 [inline] receive_buf+0x546/0x1900 drivers/net/virtio_net.c:2643 virtnet_receive_packets drivers/net/virtio_net.c:2970 [inline] virtnet_receive drivers/net/virtio_net.c:2994 [inline] virtnet_poll+0x21f0/0x2fe0 drivers/net/virtio_net.c:3083 __napi_poll+0xae/0x320 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0x696/0xe30 net/core/dev.c:7896 handle_softirqs+0x22a/0x7c0 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:debug_rcu_head_queue kernel/rcu/rcu.h:237 [inline] RIP: 0010:__call_rcu_common kernel/rcu/tree.c:3104 [inline] RIP: 0010:call_rcu+0x45/0x890 kernel/rcu/tree.c:3239 Code: 0f 85 15 05 00 00 4d 85 f6 0f 84 19 05 00 00 49 bc 00 00 00 00 00 fc ff df 48 89 df 48 c7 c6 40 fc 8d 8b e8 1d ed f9 02 89 c5 <48> 89 df 48 c7 c6 40 fc 8d 8b 31 d2 b9 01 00 00 00 e8 c5 03 fa 02 RSP: 0018:ffffc9000ce77758 EFLAGS: 00000292 RAX: 0000000000000000 RBX: ffff88802795d4c0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8dacf9d6 RDI: 00000000ffffffff RBP: 0000000000000000 R08: ffffffff8fced977 R09: 1ffffffff1f9db2e R10: dffffc0000000000 R11: fffffbfff1f9db2f R12: dffffc0000000000 R13: ffff88802ac81e80 R14: ffffffff81853ee0 R15: ffff888043c03200 context_switch kernel/sched/core.c:5263 [inline] __schedule+0x14f7/0x4fb0 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 futex_do_wait kernel/futex/waitwake.c:358 [inline] __futex_wait+0x1ee/0x420 kernel/futex/waitwake.c:687 futex_wait+0x119/0x380 kernel/futex/waitwake.c:715 do_futex+0x333/0x420 kernel/futex/syscalls.c:130 __do_sys_futex kernel/futex/syscalls.c:207 [inline] __se_sys_futex+0x3a8/0x450 kernel/futex/syscalls.c:188 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f263219acb9 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:00007f26330930e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f2632415fa8 RCX: 00007f263219acb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2632415fa8 RBP: 00007f2632415fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2632416038 R14: 00007ffcd4dfc680 R15: 00007ffcd4dfc768 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1972 Comm: syz.3.5682 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xcea/0x1270 kernel/smp.c:877 Code: 89 ee 83 e6 01 31 ff e8 94 b4 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 3f b0 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 23 b0 0b 00 eb e4 44 RSP: 0018:ffffc9000d2c74a0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110170c856d RCX: ffff88802ecc9e80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000d2c75e0 R08: ffffffff8fced977 R09: 1ffffffff1f9db2e R10: dffffc0000000000 R11: fffffbfff1f9db2f R12: ffff8880b8642b68 R13: dffffc0000000000 R14: ffff8880b873bb00 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125a28000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c340b1e CR3: 000000000e146000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline] flush_tlb_mm_range+0x5c3/0x10c0 arch/x86/mm/tlb.c:1472 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:506 [inline] tlb_flush_mmu+0x1a5/0x680 mm/mmu_gather.c:404 tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:530 free_ldt_pgtables+0x19d/0x350 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline] exit_mmap+0x187/0xb30 mm/mmap.c:1263 __mmput+0x118/0x430 kernel/fork.c:1173 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x62e/0x2310 kernel/exit.c:959 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f28f0f9acb9 Code: Unable to access opcode bytes at 0x7f28f0f9ac8f. RSP: 002b:00007f28f1e6d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffea RBX: 00007f28f1215fa0 RCX: 00007f28f0f9acb9 RDX: 0000000000000094 RSI: 00002000000000c0 RDI: 0000000000000005 RBP: 00007f28f1008bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f28f1216038 R14: 00007f28f1215fa0 R15: 00007fff87441bd8