watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz.0.866:3493]
Modules linked in:
CPU: 1 PID: 3493 Comm: syz.0.866 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:qdisc_dev include/net/sch_generic.h:603 [inline]
RIP: 0010:qdisc_tree_reduce_backlog+0xd3/0x380 net/sched/sch_api.c:783
Code: c1 e8 03 42 0f b6 04 30 84 c0 0f 85 ed 01 00 00 41 8b 9f a8 00 00 00 49 83 c7 40 4c 89 f8 48 c1 e8 03 4d 89 f5 42 80 3c 30 00 <74> 08 4c 89 ff e8 73 41 ed fd 4d 8b 37 4c 89 f0 48 c1 e8 03 42 80
RSP: 0018:ffffc900012a7058 EFLAGS: 00000246
RAX: 1ffff11021a88288 RBX: 0000000000000000 RCX: 0000000000000002
RDX: ffff8881383b0000 RSI: 0000000000000000 RDI: ffff88810d4414a8
RBP: ffffc900012a70a0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000254e08 R12: 00000000fffffff1
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88810d441440
FS:  00007fe63638a6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000110237000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 sfq_change net/sched/sch_sfq.c:737 [inline]
 sfq_init+0x19e6/0x2620 net/sched/sch_sfq.c:801
 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:5614
 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5632
 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:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5be/0x8f0 net/socket.c:2376
 ___sys_sendmsg+0x236/0x2e0 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+0x201/0x2d0 net/socket.c:2466
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fe637971e59
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:00007fe63638a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fe637beb180 RCX: 00007fe637971e59
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007fe637a07e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe637beb218 R14: 00007fe637beb180 R15: 00007ffe0f1c80c8
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