watchdog: BUG: soft lockup - CPU#1 stuck for 143s! [syz.3.2018:7134]
Modules linked in:
CPU: 1 PID: 7134 Comm: syz.3.2018 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x36/0x90 kernel/kcov.c:293
Code: 30 b4 98 7e 65 8b 15 31 b4 98 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 5b 83 b9 5c 0b 00 00 00 74 52 8b 91 38 0b 00 00 <83> fa 03 75 47 48 8b 91 40 0b 00 00 44 8b 89 3c 0b 00 00 49 c1 e1
RSP: 0018:ffffc90000a26f18 EFLAGS: 00000246
RAX: ffffffff83da9520 RBX: 0000000000000000 RCX: ffff8881116a3b40
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a26f18 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000144de0 R12: ffff8881159c1800
R13: dffffc0000000000 R14: ffff88810c04b000 R15: ffff8881159c1840
FS:  00007fc24d5696c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc24d568ff8 CR3: 00000001130a8000 CR4: 00000000003526a0
DR0: 000000000000000c DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 qdisc_tree_reduce_backlog+0x120/0x380 net/sched/sch_api.c:782
 codel_change+0x8e4/0xc20 net/sched/sch_codel.c:180
 codel_init+0x1a3/0x390 net/sched/sch_codel.c:199
 qdisc_create+0x807/0x11a0 net/sched/sch_api.c:1256
 tc_modify_qdisc+0x8ce/0x1550 net/sched/sch_api.c:-1
 rtnetlink_rcv_msg+0x9fd/0xcb0 net/core/rtnetlink.c:5654
 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2516
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5672
 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline]
 netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1348
 netlink_sendmsg+0x879/0xb80 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5be/0x8f0 net/socket.c:2435
 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2489
 __sys_sendmsg net/socket.c:2518 [inline]
 __do_sys_sendmsg net/socket.c:2527 [inline]
 __se_sys_sendmsg net/socket.c:2525 [inline]
 __x64_sys_sendmsg+0x201/0x2d0 net/socket.c:2525
 x64_sys_call+0x4b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc24eb0fe59
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:00007fc24d569028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc24ed97fa0 RCX: 00007fc24eb0fe59
RDX: 0000000000000000 RSI: 0000200000000440 RDI: 0000000000000003
RBP: 00007fc24eba5e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc24ed98038 R14: 00007fc24ed97fa0 R15: 00007ffe637611d8
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 335 Comm: kworker/u4:4 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0x8ad/0x9e0 kernel/smp.c:969
Code: 0f b6 44 05 00 84 c0 0f 85 9b 00 00 00 41 8b 1f 89 de 83 e6 01 31 ff e8 31 48 0a 00 83 e3 01 75 07 e8 77 44 0a 00 eb 42 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 10 41 f7
RSP: 0018:ffffc900078c7860 EFLAGS: 00000293
RAX: ffffffff815f713f RBX: 0000000000000001 RCX: ffff88810cb6e2c0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900078c7978 R08: ffff8881f7038e97 R09: 1ffff1103ee071d2
R10: dffffc0000000000 R11: ffffed103ee071d3 R12: ffff8881f7038e80
R13: 1ffff1103ee2784d R14: 0000000000000001 R15: ffff8881f713c268
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f202964e260 CR3: 000000000660f000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x43/0x80 kernel/smp.c:1134
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1442 [inline]
 text_poke_bp_batch+0x1d4/0x600 arch/x86/kernel/alternative.c:1642
 text_poke_flush arch/x86/kernel/alternative.c:1833 [inline]
 text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:1840
 arch_jump_label_transform_apply+0x15/0x30 arch/x86/kernel/jump_label.c:146
 __jump_label_update+0x38f/0x3b0 kernel/jump_label.c:459
 jump_label_update+0x39b/0x450 kernel/jump_label.c:830
 static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:207
 static_key_disable+0x1a/0x30 kernel/jump_label.c:215
 toggle_allocation_gate+0x3af/0x440 mm/kfence/core.c:797
 process_one_work+0x6c8/0xbb0 kernel/workqueue.c:2328
 worker_thread+0xaa0/0x1250 kernel/workqueue.c:2475
 kthread+0x3f5/0x4f0 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>