RBP: 00007f087e13f024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f087e330038 R14: 00007f087e32ffa0 R15: 00007ffdfdaca888 watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz.6.624:2856] Modules linked in: CPU: 0 PID: 2856 Comm: syz.6.624 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x60 kernel/kcov.c:196 Code: 00 00 55 48 89 e5 53 48 89 fb e8 13 00 00 00 48 8b 3d 4c c2 5e 05 48 89 de e8 34 d7 39 00 5b 5d c3 00 55 48 89 e5 48 8b 45 08 <65> 48 8b 0d b0 bb 9d 7e 65 8b 15 b5 bb 9d 7e f7 c2 00 01 ff 00 74 RSP: 0018:ffffc900014c6ed8 EFLAGS: 00000246 RAX: ffffffff83b1f9bc RBX: 00000000ffff0000 RCX: 0000000000080000 RDX: ffffc9000a4f6000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc900014c6ed8 R08: 1ffff11024e08482 R09: 1ffff11024e08492 R10: 1ffff11024e08481 R11: fffff52000298de0 R12: 0000000080010000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888129600000 FS: 00007f087cb016c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000140 CR3: 00000001314a9000 CR4: 00000000003526b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qdisc_match_from_root net/sched/sch_api.c:270 [inline] qdisc_lookup+0x20c/0x4d0 net/sched/sch_api.c:304 qdisc_tree_reduce_backlog+0x10b/0x380 net/sched/sch_api.c:783 fq_codel_change+0xa6d/0xeb0 net/sched/sch_fq_codel.c:473 fq_codel_init+0x33f/0xa40 net/sched/sch_fq_codel.c:510 qdisc_create+0x84c/0x1220 net/sched/sch_api.c:1255 tc_modify_qdisc+0x8c2/0x1470 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x9e9/0xca0 net/core/rtnetlink.c:5622 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2508 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5640 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x949/0xb70 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] ____sys_sendmsg+0x5be/0x8f0 net/socket.c:2377 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2431 __sys_sendmsg net/socket.c:2460 [inline] __do_sys_sendmsg net/socket.c:2469 [inline] __se_sys_sendmsg net/socket.c:2467 [inline] __x64_sys_sendmsg+0x201/0x2d0 net/socket.c:2467 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f087e0a80d9 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:00007f087cb01028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f087e32ffa0 RCX: 00007f087e0a80d9 RDX: 0000000000008840 RSI: 0000200000000740 RDI: 0000000000000006 RBP: 00007f087e13f024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f087e330038 R14: 00007f087e32ffa0 R15: 00007ffdfdaca888 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 48 Comm: kworker/u4:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline] RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:229 [inline] RIP: 0010:smp_call_function_single+0x207/0x490 kernel/smp.c:517 Code: 74 24 48 44 89 f6 83 e6 01 31 ff e8 b3 90 0a 00 41 83 e6 01 49 bc 00 00 00 00 00 fc ff df 75 0a e8 ee 8c 0a 00 e9 a4 00 00 00 90 f7 44 24 48 01 00 00 00 0f 84 8f 00 00 00 e8 d4 8c 0a 00 eb RSP: 0018:ffffc900009cf700 EFLAGS: 00000293 RAX: ffffffff815a24ec RBX: 0000000000000000 RCX: ffff888101dd62c0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900009cf7f0 R08: ffff8881f7057647 R09: 1ffff1103ee0aec8 R10: dffffc0000000000 R11: ffffed103ee0aec9 R12: dffffc0000000000 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff92000139ee4 FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4937299f39 CR3: 000000000640f000 CR4: 00000000003526a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: smp_call_function_many_cond+0x8f5/0x9d0 kernel/smp.c:653 smp_call_function_many kernel/smp.c:716 [inline] smp_call_function kernel/smp.c:738 [inline] on_each_cpu+0xab/0x180 kernel/smp.c:837 text_poke_sync arch/x86/kernel/alternative.c:1568 [inline] text_poke_bp_batch+0x1cb/0x5f0 arch/x86/kernel/alternative.c:1768 text_poke_flush arch/x86/kernel/alternative.c:1959 [inline] text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:1966 arch_jump_label_transform_apply+0x15/0x30 arch/x86/kernel/jump_label.c:126 __jump_label_update+0x38f/0x3b0 kernel/jump_label.c:459 jump_label_update+0x34c/0x3e0 kernel/jump_label.c:825 static_key_enable_cpuslocked+0x126/0x240 kernel/jump_label.c:177 static_key_enable+0x1a/0x30 kernel/jump_label.c:190 toggle_allocation_gate+0xba/0x440 mm/kfence/core.c:624 process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301 worker_thread+0xa8e/0x13c0 kernel/workqueue.c:2447 kthread+0x324/0x3b0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298