RBP: 00007f1c37fc9b70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1c381b8218 R14: 00007f1c381b8180 R15: 00007fff9c217408 watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz.2.2185:8236] Modules linked in: CPU: 1 PID: 8236 Comm: syz.2.2185 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 RIP: 0010:qdisc_dev include/net/sch_generic.h:603 [inline] RIP: 0010:qdisc_match_from_root net/sched/sch_api.c:263 [inline] RIP: 0010:qdisc_lookup+0x288/0x4d0 net/sched/sch_api.c:309 Code: 3c 28 00 74 08 4c 89 f7 e8 d5 a5 ec fd 4d 8b 36 4d 8d 7e 40 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 b8 a5 ec fd <4d> 8b 3f 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 9f RSP: 0018:ffffc90001736ee8 EFLAGS: 00000246 RAX: 1ffff11028e2f508 RBX: 00000000ffff0000 RCX: ffff888147aba800 RDX: 0000000000000000 RSI: 00000000ffff0000 RDI: 0000000000000000 RBP: ffffc90001736f18 R08: 1ffff11025c36482 R09: 1ffff11025c36492 R10: 1ffff11025c36481 R11: fffff520002e6de0 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88814717a800 R15: ffff88814717a840 FS: 00007f1c369476c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1c36904ff8 CR3: 000000011e567000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: qdisc_tree_reduce_backlog+0x10b/0x380 net/sched/sch_api.c:800 fq_codel_change+0xa6d/0xeb0 net/sched/sch_fq_codel.c:473 fq_codel_init+0x2f0/0x8c0 net/sched/sch_fq_codel.c:512 qdisc_create+0x84c/0x1220 net/sched/sch_api.c:1272 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: 0033:0x7f1c37f31b19 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:00007f1c36947028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f1c381b8180 RCX: 00007f1c37f31b19 RDX: 0000000000000000 RSI: 0000200000000380 RDI: 0000000000000007 RBP: 00007f1c37fc9b70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1c381b8218 R14: 00007f1c381b8180 R15: 00007fff9c217408 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline] NMI backtrace for cpu 0 skipped: idling at default_idle+0x12/0x20 arch/x86/kernel/process.c:717