INFO: task syz.0.4377:21578 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.4377 state:D stack:27152 pid:21578 tgid:21577 ppid:16550 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 nfsd_nl_listener_get_doit+0x104/0x610 fs/nfsd/nfsctl.c:2098 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738 __sys_sendmsg net/socket.c:2770 [inline] __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa50d99ce59 RSP: 002b:00007fa50e852028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa50dc15fa0 RCX: 00007fa50d99ce59 RDX: 0000000020040000 RSI: 0000200000000140 RDI: 0000000000000004 RBP: 00007fa50da32e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa50dc16038 R14: 00007fa50dc15fa0 R15: 00007ffeb2400308 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6342 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: bond7 bond_mii_monitor RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_cmp4+0x36/0x90 kernel/kcov.c:288 Code: 18 58 74 11 65 8b 0d 39 58 74 11 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 17 00 00 00 74 52 8b 8a f8 16 00 00 <83> f9 03 75 47 48 8b 8a 00 17 00 00 44 8b 8a fc 16 00 00 49 c1 e1 RSP: 0018:ffffc90007097af8 EFLAGS: 00000246 RAX: ffffffff818e3fa8 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888031711f00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90007097ce8 R08: ffffffff903114f7 R09: 1ffffffff206229e R10: dffffc0000000000 R11: fffffbfff206229f R12: ffff888036d16058 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff11006da2c0b FS: 0000000000000000(0000) GS:ffff88812537b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fddf2b47e20 CR3: 000000000e746000 CR4: 00000000003526f0 Call Trace: process_one_work kernel/workqueue.c:3326 [inline] process_scheduled_works+0xc98/0x14e0 kernel/workqueue.c:3397 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245