INFO: task syz.4.445:7672 blocked for more than 143 seconds. Not tainted 6.12.0-syzkaller-10684-gf1cd565ce577 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.445 state:D stack:24792 pid:7672 tgid:7671 ppid:5866 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735 nfsd_nl_rpc_status_get_dumpit+0xdc/0x1a60 fs/nfsd/nfsctl.c:1558 genl_dumpit+0x10d/0x1b0 net/netlink/genetlink.c:1027 netlink_dump+0x64d/0xe10 net/netlink/af_netlink.c:2317 __netlink_dump_start+0x5a2/0x790 net/netlink/af_netlink.c:2432 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:1076 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1192 [inline] genl_rcv_msg+0x88c/0xec0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x269/0x350 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7eff40f80849 RSP: 002b:00007eff41dd5058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007eff41145fa0 RCX: 00007eff40f80849 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003 RBP: 00007eff40ff3986 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007eff41145fa0 R15: 00007ffed05ed618 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e93c560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/1:1/46: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000b67d00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000b67d00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fce8188 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/u8:9/3001: #0: ffff8880b863e798 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 #1: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x387/0x7a0 kernel/sched/psi.c:975 1 lock held by dhcpcd/5523: #0: ffffffff8fce8188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fce8188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #0: ffffffff8fce8188 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd04/0x24f0 net/core/rtnetlink.c:4006 2 locks held by getty/5605: #0: ffff888034be20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.1.328/7306: #0: ffffffff8fd4ed10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8ec13208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964 3 locks held by syz.4.445/7672: #0: ffffffff8fd4ed10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffff88807e3ff6c8 (nlk_cb_mutex-GENERIC){+.+.}-{4:4}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2396 #2: ffffffff8ec13208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_rpc_status_get_dumpit+0xdc/0x1a60 fs/nfsd/nfsctl.c:1558 3 locks held by kworker/u8:12/8220: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900035e7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900035e7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fce8188 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 5 locks held by kworker/u8:14/8231: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003897d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003897d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcdb650 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:586 #3: ffffffff8fce8188 (rtnl_mutex){+.+.}-{4:4}, at: cleanup_net+0x6af/0xcc0 net/core/net_namespace.c:622 #4: ffffffff8e941af8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #4: ffffffff8e941af8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 2 locks held by syz.0.682/8789: #0: ffffffff8fd4ed10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8ec13208 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_get_doit+0x115/0x5e0 fs/nfsd/nfsctl.c:2121 2 locks held by syz-executor/9413: 3 locks held by syz-executor/14641: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-10684-gf1cd565ce577 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xffb/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 14641 Comm: syz-executor Not tainted 6.12.0-syzkaller-10684-gf1cd565ce577 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:hlist_bl_unhashed include/linux/list_bl.h:54 [inline] RIP: 0010:d_unhashed include/linux/dcache.h:354 [inline] RIP: 0010:retain_dentry fs/dcache.c:708 [inline] RIP: 0010:fast_dput+0x11c/0x420 fs/dcache.c:821 Code: 4d 7c ff 85 db 74 0a e8 82 49 7c ff e9 d6 00 00 00 4c 89 e5 48 c1 ed 03 42 0f b6 44 3d 00 84 c0 0f 85 72 02 00 00 45 8b 2c 24 <49> 8d 5c 24 48 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df RSP: 0018:ffffc900037b78e0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88802ef48000 RDX: ffff88802ef48000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 1ffff1100bfeb000 R08: ffffffff82199af5 R09: fffff520006f6f0c R10: dffffc0000000000 R11: fffff520006f6f0c R12: ffff88805ff58000 R13: 0000000040500000 R14: ffff88805ff580b8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f67b3c77d60 CR3: 000000000e738000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dput+0xe8/0x2b0 fs/dcache.c:861 __fput+0x5ba/0xa50 fs/file_table.c:458 task_work_run+0x24f/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3016 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f44e637f057 Code: Unable to access opcode bytes at 0x7f44e637f02d. RSP: 002b:00007fff46f2ec68 EFLAGS: 00000202 ORIG_RAX: 000000000000005a RAX: 0000000000000000 RBX: 00007fff46f2ecd0 RCX: 00007f44e637f057 RDX: 0000000000000000 RSI: 00000000000001ff RDI: 00007fff46f2ecd0 RBP: 0000000000000002 R08: 0000000000000004 R09: 0000000000000001 R10: 00007f44e7257038 R11: 0000000000000202 R12: 00007fff46f2ecd0 R13: 00007fff46f2ecd8 R14: 0000000000000009 R15: 0000000000000000