watchdog: BUG: soft lockup - CPU#0 stuck for 144s! [syz.5.48:6419] Modules linked in: irq event stamp: 11435133 hardirqs last enabled at (11435132): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:200 hardirqs last disabled at (11435133): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1050 softirqs last enabled at (244184): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last enabled at (244184): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last enabled at (244184): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 softirqs last disabled at (244187): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (244187): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (244187): [] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 CPU: 0 UID: 0 PID: 6419 Comm: syz.5.48 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline] RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x1315/0x2390 arch/x86/kernel/unwind_orc.c:494 Code: 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 07 <4c> 01 f8 49 8d 4f 04 4c 39 e0 48 0f 46 e9 49 8d 47 fc 48 0f 47 d8 RSP: 0018:ffffc90000007518 EFLAGS: 00000246 RAX: fffffffff2589d36 RBX: ffffffff8fbf9674 RCX: dffffc0000000000 RDX: ffffffff8fbf9654 RSI: ffffffff903fab68 RDI: ffffffff8be33220 RBP: ffffffff8fbf9654 R08: 0000000000000009 R09: ffffffff8172c195 R10: dffffc0000000000 R11: ffffffff81ac3930 R12: ffffffff82183359 R13: ffffffff8fbf9654 R14: ffffc900000075e8 R15: ffffffff8fbf9664 FS: 00007ff8111d36c0(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f84259f6d58 CR3: 0000000078652000 CR4: 00000000003526f0 Call Trace: 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:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4281 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659 alloc_skb include/linux/skbuff.h:1336 [inline] ndisc_alloc_skb+0x9f/0x480 net/ipv6/ndisc.c:420 ndisc_send_rs+0x2b5/0x630 net/ipv6/ndisc.c:706 addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4037 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] RIP: 0010:rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 Code: 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 53 e8 b6 fe d3 09 85 c0 74 26 31 db e8 eb 2d 01 00 84 c0 74 20 e8 62 76 01 00 <84> c0 74 17 48 c7 c7 a0 9e 13 8e be ff ff ff ff 5b e9 9c fa d3 09 RSP: 0018:ffffc90003d762b0 EFLAGS: 00000282 RAX: 1ffffffff1c27e01 RBX: 0000000000000000 RCX: e49cfc49aafbf500 RDX: ffff8880342a8000 RSI: ffffffff8be33260 RDI: ffff8880b863afa8 RBP: ffffc90003d763b8 R08: 0000000000000000 R09: ffffffff81cb03c7 R10: dffffc0000000000 R11: fffff91ffff93bd0 R12: 0000000000000001 R13: ffffc90003d76340 R14: ffff88805b3e2a00 R15: ffffffff8e009008 trace_call_bpf+0x1ad/0x850 kernel/trace/bpf_trace.c:146 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:10911 do_perf_trace_lock include/trace/events/lock.h:50 [inline] perf_trace_lock+0x2f8/0x3b0 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+0x3b2/0x3e0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680 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:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tcf_idr_create+0x5d/0x6c0 net/sched/act_api.c:781 tcf_idr_create_from_flags+0x60/0x80 net/sched/act_api.c:841 tcf_ct_init+0x3c5/0x1950 net/sched/act_ct.c:1376 tcf_action_init_1+0x463/0x6d0 net/sched/act_api.c:1431 tcf_action_init+0x2cf/0xab0 net/sched/act_api.c:1506 tcf_action_add net/sched/act_api.c:2100 [inline] tc_ctl_action+0x430/0xbd0 net/sched/act_api.c:2157 rtnetlink_rcv_msg+0x779/0xb70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff81038ebe9 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:00007ff8111d3038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ff8105b6090 RCX: 00007ff81038ebe9 RDX: 0000000010000000 RSI: 0000200000000080 RDI: 0000000000000010 RBP: 00007ff810411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff8105b6128 R14: 00007ff8105b6090 R15: 00007ffe26a18b28 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 3947 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: writeback wb_workfn (flush-8:0) RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d a4 48 fe 0b 48 89 de 5b e9 53 97 58 00 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 0c 25 08 40 a0 92 65 8b 15 c8 93 e0 10 81 e2 00 01 ff 00 RSP: 0018:ffffc9000d17e058 EFLAGS: 00000202 RAX: ffffffff81b44e0b RBX: 1ffff110170c8341 RCX: ffff888031f45a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000d17e1e0 R08: ffff88802ee21f87 R09: 1ffff11005dc43f0 R10: dffffc0000000000 R11: ffffffff8174ae50 R12: ffff8880b8641a08 R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125d1c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555754d35c8 CR3: 000000007804c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: csd_lock_wait kernel/smp.c:342 [inline] smp_call_function_many_cond+0xd4b/0x12d0 kernel/smp.c:877 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451 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:1059 page_mkclean_one+0x1c0/0x280 mm/rmap.c:1100 __rmap_walk_file+0x464/0x620 mm/rmap.c:2905 rmap_walk mm/rmap.c:2949 [inline] folio_mkclean+0x297/0x390 mm/rmap.c:1132 folio_clear_dirty_for_io+0x1fa/0x8c0 mm/page-writeback.c:2962 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+0x32b/0x550 mm/page-writeback.c:2634 __writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline] wb_do_writeback fs/fs-writeback.c:2315 [inline] wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245