INFO: task syz.2.127:6591 blocked for more than 143 seconds. Not tainted 6.12.0-syzkaller-09435-g2c22dc1ee3a1 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.127 state:D stack:27088 pid:6591 tgid:6588 ppid:5855 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 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+0x62b/0xa60 kernel/locking/mutex.c:735 nfsd_nl_version_set_doit+0xc5/0x7a0 fs/nfsd/nfsctl.c:1813 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2541 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2583 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2637 __sys_sendmsg+0x16e/0x220 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6e60b7e819 RSP: 002b:00007f6e61a23038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6e60d36080 RCX: 00007f6e60b7e819 RDX: 0000000000004010 RSI: 0000000020000080 RDI: 0000000000000005 RBP: 00007f6e60bf175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6e60d36080 R15: 00007ffe4d40b898 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8dfbaf40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8dfbaf40 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8dfbaf40 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:6/2908: 2 locks held by getty/5613: #0: ffff888034f2a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:3/5856: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x126b/0x1b30 kernel/workqueue.c:3204 #1: ffffc9000406fd80 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffffffff8dfc6740 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x700 kernel/rcu/tree.c:4565 2 locks held by syz.1.51/6158: #0: ffffffff8fd71010 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e3bb708 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1671 2 locks held by syz-executor/6327: #0: ffff88804f0d40e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88804f0d40e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88804f0d40e0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:505 #1: ffffffff8e3bb708 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625 2 locks held by syz.2.127/6591: #0: ffffffff8fd71010 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e3bb708 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc5/0x7a0 fs/nfsd/nfsctl.c:1813 2 locks held by kworker/u8:8/6846: 2 locks held by syz-executor/6903: #0: ffff888043c340e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888043c340e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888043c340e0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:505 #1: ffffffff8e3bb708 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625 2 locks held by syz-executor/7888: #0: ffff88807ebd20e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807ebd20e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807ebd20e0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:505 #1: ffffffff8e3bb708 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625 2 locks held by syz.0.372/8263: #0: ffffffff8fd71010 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e3bb708 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xe3/0x1b40 fs/nfsd/nfsctl.c:1964 1 lock held by syz.1.553/9429: 1 lock held by syz.9.552/9430: 2 locks held by syz.9.552/9433: 3 locks held by syz.8.556/9447: 1 lock held by syz.9.568/9482: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-09435-g2c22dc1ee3a1 #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+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 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+0xf14/0x1240 kernel/hung_task.c:397 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 2908 Comm: kworker/u8:6 Not tainted 6.12.0-syzkaller-09435-g2c22dc1ee3a1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data+0x18/0x90 kernel/kcov.c:246 Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 6f de 75 7e 65 8b 05 70 de 75 7e 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 RSP: 0018:ffffc9000b977b88 EFLAGS: 00000246 RAX: 0000000080000000 RBX: ffff888063fb5948 RCX: ffffffff8ae33c0b RDX: ffff88802f545a00 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000329 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000001 R13: ffff88801aca0000 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b323c8ff8 CR3: 000000000dd7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock include/linux/rcupdate.h:850 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x17b/0x1060 net/batman-adv/network-coding.c:719 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244