INFO: task syz.0.433:6420 blocked for more than 144 seconds. Not tainted 6.1.129-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.433 state:D stack:28616 pid:6420 ppid:4251 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 inode_lock_nested include/linux/fs.h:793 [inline] filename_create+0x25c/0x530 fs/namei.c:3876 do_mkdirat+0xba/0x360 fs/namei.c:4121 __do_sys_mkdirat fs/namei.c:4146 [inline] __se_sys_mkdirat fs/namei.c:4144 [inline] __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4144 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f440778d169 RSP: 002b:00007f4408516038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f44079a6240 RCX: 00007f440778d169 RDX: 0000000000000000 RSI: 0000400000000340 RDI: ffffffffffffff9c RBP: 00007f440780e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f44079a6240 R15: 00007ffe244b8608 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e850 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32f050 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 3 locks held by kworker/1:0/22: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc900001c7d20 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8d333cb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d333cb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by khungtaskd/27: #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e680 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 3 locks held by kworker/1:1/40: #0: ffff88802fcf3138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90000b17d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16e0 net/ipv6/addrconf.c:4134 2 locks held by dhcpcd/3915: #0: ffffffff8e5354e8 (vlan_ioctl_mutex){+.+.}-{3:3}, at: sock_ioctl+0x526/0x770 net/socket.c:1283 #1: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: vlan_ioctl_handler+0x114/0x980 net/8021q/vlan.c:553 2 locks held by getty/4008: #0: ffff88803066c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198 2 locks held by kworker/u4:16/4599: 4 locks held by kworker/u4:18/4701: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003867d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e542f90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xd20 net/core/net_namespace.c:594 #3: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: vti6_exit_batch_net+0xb0/0x410 net/ipv6/ip6_vti.c:1185 2 locks held by kworker/1:7/5492: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc900046afd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 3 locks held by kworker/u4:23/5719: 2 locks held by syz.0.433/6419: 2 locks held by syz.0.433/6420: #0: ffff88806686a460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393 #1: ffff8880551d5e48 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #1: ffff8880551d5e48 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876 3 locks held by ext4lazyinit/6404: 1 lock held by syz-executor/6793: #0: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147 3 locks held by syz.5.485/6827: #0: ffff8880794b10b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:507 [inline] #0: ffff8880794b10b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1ff/0x500 net/bluetooth/hci_core.c:2706 #1: ffff8880794b0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0xfc0 net/bluetooth/hci_sync.c:5165 #2: ffffffff8d333cb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d333cb8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 4 locks held by syz-executor/6890: #0: ffffffff8e5b09f0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860 #1: ffff88805972a690 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: __netlink_dump_start+0x136/0x6d0 net/netlink/af_netlink.c:2287 #2: ffff8880624b12f8 (&devlink->lock_key#13){+.+.}-{3:3}, at: devl_lock net/devlink/leftover.c:275 [inline] #2: ffff8880624b12f8 (&devlink->lock_key#13){+.+.}-{3:3}, at: devlink_nl_cmd_port_get_dumpit+0x171/0x5a0 net/devlink/leftover.c:1537 #3: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: devlink_nl_port_fill+0x1bc/0x920 net/devlink/leftover.c:1276 1 lock held by syz-executor/6922: #0: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147 1 lock held by syz-executor/6939: #0: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e54faa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147 1 lock held by syz.5.495/6950: #0: ffffffff8d333b80 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:4019 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6419 Comm: syz.0.433 Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:check_preemption_disabled+0x5c/0x110 lib/smp_processor_id.c:19 Code: 25 28 00 00 00 48 3b 44 24 08 0f 85 c7 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 04 24 00 02 00 00 74 c9 49 89 f6 49 89 ff 65 4c 8b 25 bd 74 51 RSP: 0018:ffffc9000462f248 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 0000000000000000 RCX: 0000000000080000 RDX: ffffc9000f92f000 RSI: ffffffff8b1a5260 RDI: ffffffff8b5f6d80 RBP: ffffc9000462f3b0 R08: ffffffff8201263a R09: fffff940002ec997 R10: 0000000000000000 R11: dffffc0000000001 R12: fffffffffffffff9 R13: 0000000000000000 R14: 0000000000000400 R15: 0000000000036930 FS: 00007f44085376c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000400000e13030 CR3: 0000000053941000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lookup_bh_lru fs/buffer.c:1274 [inline] __find_get_block+0x1ac/0x1120 fs/buffer.c:1303 __getblk_slow fs/buffer.c:1034 [inline] __getblk_gfp+0x146/0xa20 fs/buffer.c:1333 sb_getblk include/linux/buffer_head.h:356 [inline] ext4_getblk+0x2a7/0x7c0 fs/ext4/inode.c:899 ext4_bread_batch+0x5f/0x4d0 fs/ext4/inode.c:966 __ext4_find_entry+0xfd1/0x1b20 fs/ext4/namei.c:1671 ext4_lookup_entry fs/ext4/namei.c:1774 [inline] ext4_lookup+0x176/0x740 fs/ext4/namei.c:1842 lookup_open fs/namei.c:3460 [inline] open_last_lookups fs/namei.c:3550 [inline] path_openat+0x10fb/0x2e60 fs/namei.c:3780 do_filp_open+0x230/0x480 fs/namei.c:3810 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318 do_sys_open fs/open.c:1334 [inline] __do_sys_open fs/open.c:1342 [inline] __se_sys_open fs/open.c:1338 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1338 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f440778d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4408537038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f44079a6160 RCX: 00007f440778d169 RDX: 0000000000000000 RSI: 0000000000181042 RDI: 0000400000000040 RBP: 00007f440780e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f44079a6160 R15: 00007ffe244b8608