watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz.8.1397:5889]
Modules linked in:
CPU: 1 PID: 5889 Comm: syz.8.1397 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x10/0x60 kernel/kcov.c:197
Code: 89 fb e8 13 00 00 00 48 8b 3d 0c b7 3f 05 48 89 de e8 54 4f 39 00 5b 5d c3 00 55 48 89 e5 48 8b 45 08 65 48 8b 0d f0 c8 9e 7e <65> 8b 15 f5 c8 9e 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74
RSP: 0018:ffffc900033f6eb8 EFLAGS: 00000286
RAX: ffffffff83ab1318 RBX: 00000000ffff0000 RCX: ffff888119eee2c0
RDX: ffff888119eee2c0 RSI: 00000000ffff0000 RDI: ffff888104f94000
RBP: ffffc900033f6eb8 R08: ffff888119eee2c0 R09: 0000000000000002
R10: 00000000ffffffff R11: 0000000000000000 R12: 00000000fffffff1
R13: ffff88810c70b0cc R14: ffff888104f94000 R15: ffff88810c70b040
FS:  00007f46dc5ae6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f46dc56bf98 CR3: 0000000134725000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 qdisc_lookup+0x18/0x4e0 net/sched/sch_api.c:299
 qdisc_tree_reduce_backlog+0x111/0x340 net/sched/sch_api.c:783
 fq_codel_change+0xa27/0xe40 net/sched/sch_fq_codel.c:436
 fq_codel_init+0x342/0xa20 net/sched/sch_fq_codel.c:473
 qdisc_create+0x780/0x1040 net/sched/sch_api.c:1255
 tc_modify_qdisc+0x8da/0x14c0 net/sched/sch_api.c:1715
 rtnetlink_rcv_msg+0x9db/0xb90 net/core/rtnetlink.c:5610
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2376
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2430
 __sys_sendmsg net/socket.c:2459 [inline]
 __do_sys_sendmsg net/socket.c:2468 [inline]
 __se_sys_sendmsg net/socket.c:2466 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2466
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f46ddb46749
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:00007f46dc5ae038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f46ddd9cfa0 RCX: 00007f46ddb46749
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000002
RBP: 00007f46ddbcaf91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f46ddd9d038 R14: 00007f46ddd9cfa0 R15: 00007fff9a57d878
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