watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [syz.9.1201:11652] Modules linked in: irq event stamp: 11088405 hardirqs last enabled at (11088404): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:214 hardirqs last disabled at (11088405): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1052 softirqs last enabled at (10564232): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (10564232): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (10564232): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 softirqs last disabled at (10564235): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (10564235): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (10564235): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 11652 Comm: syz.9.1201 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:0xffffffffa00034ac Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc <41> ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc 41 ff e3 cc cc cc RSP: 0018:ffffc90000006d00 EFLAGS: 00000282 RAX: ffffffff8b477bd5 RBX: ffffc90000006dc0 RCX: 3376cc7cf9acb200 RDX: 0000000000000001 RSI: ffffffff8b477bd5 RDI: ffffc90000006dc0 RBP: ffffc90000006d90 R08: ffffc900000069ef R09: 0000000000000000 R10: ffffc900000069e0 R11: ffffffff81ac3f50 R12: ffff88802a78dac0 R13: 00000000000000f0 R14: ffffffff81ac3f50 R15: ffffc90000006d08 FS: 00007f3fbab116c0(0000) GS:ffff88812613d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f01303b3ad8 CR3: 000000004a488000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: 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 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4970 [inline] slab_alloc_node mm/slub.c:5280 [inline] kmem_cache_alloc_node_noprof+0x433/0x710 mm/slub.c:5332 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1383 [inline] arp_create+0x189/0x990 net/ipv4/arp.c:561 arp_send_dst+0xa5/0x340 net/ipv4/arp.c:314 arp_process+0x13ab/0x17a0 net/ipv4/arp.c:854 NF_HOOK+0x310/0x3a0 include/linux/netfilter.h:-1 __netif_receive_skb_list_ptype net/core/dev.c:6127 [inline] __netif_receive_skb_list_core+0x75a/0x800 net/core/dev.c:6169 __netif_receive_skb_list net/core/dev.c:6221 [inline] netif_receive_skb_list_internal+0x96f/0xcb0 net/core/dev.c:6312 gro_normal_list include/net/gro.h:524 [inline] gro_normal_one include/net/gro.h:544 [inline] gro_skb_finish net/core/gro.c:603 [inline] gro_receive_skb+0x642/0xce0 net/core/gro.c:633 receive_buf+0xa0e/0x15e0 drivers/net/virtio_net.c:2648 virtnet_receive_packets drivers/net/virtio_net.c:2996 [inline] virtnet_receive drivers/net/virtio_net.c:3020 [inline] virtnet_poll+0x1fe1/0x2db0 drivers/net/virtio_net.c:3114 __napi_poll+0xc7/0x360 net/core/dev.c:7594 napi_poll net/core/dev.c:7657 [inline] net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784 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:__schedule+0x7f/0x4cc0 kernel/sched/core.c:6785 Code: b5 31 7c 8d 48 c7 84 24 10 01 00 00 30 27 47 8b 48 8d 8c 24 00 01 00 00 48 c1 e9 03 48 b8 f1 f1 f1 f1 04 f2 00 00 4a 89 04 31 <48> b8 f2 f2 f2 f2 f2 00 f2 f2 4a 89 44 31 09 42 c7 44 31 11 f2 00 RSP: 0018:ffffc90004b7f4a0 EFLAGS: 00000a06 RAX: 0000f204f1f1f1f1 RBX: 0000000000000000 RCX: 1ffff9200096feb4 RDX: 0000000000000000 RSI: ffffffff8d70d468 RDI: ffffc90004b7f630 RBP: ffffc90004b7f6b0 R08: ffffffff8f7cdc77 R09: 1ffffffff1ef9b8e R10: dffffc0000000000 R11: fffffbfff1ef9b8f R12: 0000000000000000 R13: 0000000000000001 R14: dffffc0000000000 R15: 1ffff9200096fed8 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:217 [inline] RIP: 0010:unwind_next_frame+0x214/0x2390 arch/x86/kernel/unwind_orc.c:494 Code: ef 08 8b 15 be 34 1f 0c 8d 42 ff 44 39 f8 0f 86 65 18 00 00 44 89 f8 4c 8d 2c 85 2c f7 b4 90 4c 89 e8 48 c1 e8 03 0f b6 04 28 <84> c0 48 89 eb 0f 85 1c 1c 00 00 45 8b 6d 00 44 89 f8 ff c0 48 8d RSP: 0018:ffffc90004b7f838 EFLAGS: 00000a03 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 3376cc7cf9acb200 RDX: 00000000000a4a16 RSI: ffffffff8bbf0740 RDI: ffffffff8bbf0700 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81739d25 R10: ffffc90004b7f5e0 R11: ffffffff81ac3f50 R12: ffffffff843a1838 R13: ffffffff90c1df8c R14: ffffc90004b7f908 R15: 0000000000033a18 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 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4970 [inline] slab_alloc_node mm/slub.c:5280 [inline] kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5287 lsm_inode_alloc security/security.c:761 [inline] security_inode_alloc+0x39/0x330 security/security.c:1736 inode_init_always_gfp+0x9ed/0xdc0 fs/inode.c:306 inode_init_always include/linux/fs.h:3312 [inline] alloc_inode+0x82/0x1b0 fs/inode.c:353 new_inode_pseudo include/linux/fs.h:3395 [inline] sock_alloc net/socket.c:637 [inline] __sock_create+0x12d/0x9f0 net/socket.c:1569 sock_create net/socket.c:1663 [inline] __sys_socket_create net/socket.c:1700 [inline] __sys_socket+0xd7/0x1b0 net/socket.c:1747 __do_sys_socket net/socket.c:1761 [inline] __se_sys_socket net/socket.c:1759 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1759 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: 0033:0x7f3fb9b8f6c9 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:00007f3fbab11038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007f3fb9de5fa0 RCX: 00007f3fb9b8f6c9 RDX: 0000000000000010 RSI: 0000000000000003 RDI: 0000000000000010 RBP: 00007f3fb9c11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3fb9de6038 R14: 00007f3fb9de5fa0 R15: 00007ffc96ba58e8 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7548 Comm: kworker/u8:23 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: writeback wb_workfn (flush-8:0) RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877 Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 b6 73 0b 00 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 RSP: 0018:ffffc90004da6040 EFLAGS: 00000293 RAX: ffffffff81b4a74b RBX: 1ffff11017108441 RCX: ffff88802b098000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90004da61c0 R08: ffff8880309e5547 R09: 1ffff1100613caa8 R10: dffffc0000000000 R11: ffffffff81759770 R12: ffff8880b8842208 R13: dffffc0000000000 R14: ffff8880b893b240 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812623d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555592ece5c8 CR3: 000000007453a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 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:1381 [inline] flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1471 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline] ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101 page_vma_mkclean_one+0x406/0x740 mm/rmap.c:1041 page_mkclean_one+0x1c0/0x280 mm/rmap.c:1082 __rmap_walk_file+0x467/0x620 mm/rmap.c:2918 rmap_walk mm/rmap.c:2962 [inline] folio_mkclean+0x297/0x390 mm/rmap.c:1114 folio_clear_dirty_for_io+0x1f5/0x880 mm/page-writeback.c:2938 mpage_submit_folio+0x86/0x2b0 fs/ext4/inode.c:2061 mpage_process_page_bufs+0x6d5/0x8e0 fs/ext4/inode.c:2191 mpage_prepare_extent_to_map+0xe6c/0x16e0 fs/ext4/inode.c:2736 ext4_do_writepages+0xba0/0x4610 fs/ext4/inode.c:2877 ext4_writepages+0x205/0x350 fs/ext4/inode.c:3025 do_writepages+0x32e/0x550 mm/page-writeback.c:2604 __writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1719 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:2015 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2086 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2197 wb_check_old_data_flush fs/fs-writeback.c:2301 [inline] wb_do_writeback fs/fs-writeback.c:2354 [inline] wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2382 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