INFO: task syz-executor:4261 blocked for more than 144 seconds. Not tainted 6.1.128-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20832 pid:4261 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 deactivate_super+0xa9/0xe0 fs/super.c:362 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe226b8e117 RSP: 002b:00007ffe7b4f5268 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fe226c0e08c RCX: 00007fe226b8e117 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe7b4f5320 RBP: 00007ffe7b4f5320 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe7b4f63b0 R13: 00007fe226c0e08c R14: 00000000000428a5 R15: 00007ffe7b4f63f0 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b290 (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: ffffffff8d32ba90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 2 locks held by getty/4009: #0: ffff88814da0b098 (&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+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4261: #0: ffff88807fc940e0 (&type->s_umount_key#31){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362 4 locks held by kworker/u4:14/4523: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000511fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4ffad0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xd20 net/core/net_namespace.c:594 #3: ffffffff8e50bfa8 (rtnl_mutex){+.+.}-{3:3}, at: ppp_exit_net+0xe0/0x3b0 drivers/net/ppp/ppp_generic.c:1144 2 locks held by kworker/1:8/5706: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900032c7d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 3 locks held by ext4lazyinit/6608: 1 lock held by syz-executor/6781: 6 locks held by kworker/1:10/7048: #0: ffff888141e82938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000379fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888146b6a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #2: ffff888146b6a190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5730 drivers/usb/core/hub.c:5803 #3: ffff888146b6d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3161 [inline] #3: ffff888146b6d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5375 [inline] #3: ffff888146b6d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5619 [inline] #3: ffff888146b6d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5775 [inline] #3: ffff888146b6d4f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x31e5/0x5730 drivers/usb/core/hub.c:5857 #4: ffff888146b34d68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5376 [inline] #4: ffff888146b34d68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5619 [inline] #4: ffff888146b34d68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5775 [inline] #4: ffff888146b34d68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x3213/0x5730 drivers/usb/core/hub.c:5857 #5: ffffffff8de5b230 (ehci_cf_port_reset_rwsem){.+.+}-{3:3}, at: hub_port_reset+0x1f4/0x1f00 drivers/usb/core/hub.c:3018 2 locks held by syz.3.1245/8261: #0: ffffffff8e50bfa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e50bfa8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6147 #1: ffffffff8d3306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8d3306b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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+0x1ae/0x3f0 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: 6608 Comm: ext4lazyinit Not tainted 6.1.128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:__lock_acquire+0xf7f/0x1f80 kernel/locking/lockdep.c:5045 Code: 00 8b 1b 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 60 02 25 91 be 08 00 00 00 e8 89 79 77 00 48 0f a3 1d c1 4a ba 0f <0f> 83 bb 01 00 00 48 8d 04 5b 48 c1 e0 06 48 8d 98 20 81 bd 90 48 RSP: 0018:ffffc9000dc1f6a0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 00000000000004f8 RCX: ffffffff816ab797 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff912502f8 RBP: d0640d21da66df10 R08: dffffc0000000000 R09: fffffbfff224a060 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88802b674658 R13: ffff88802b673b80 R14: 0000000000000000 R15: 1ffff110056ce8da FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcaef978ab8 CR3: 000000005d4dd000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] mapping_get_entry mm/filemap.c:1878 [inline] __filemap_get_folio+0x171/0xe80 mm/filemap.c:1943 pagecache_get_page+0x28/0x250 mm/folio-compat.c:110 find_get_page_flags include/linux/pagemap.h:602 [inline] __find_get_block_slow fs/buffer.c:202 [inline] __find_get_block+0x3d8/0x1120 fs/buffer.c:1307 __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_read_block_bitmap_nowait+0x1ff/0x980 fs/ext4/balloc.c:482 ext4_mb_prefetch+0x46d/0x640 fs/ext4/mballoc.c:2587 ext4_run_li_request fs/ext4/super.c:3644 [inline] ext4_lazyinit_thread+0x54d/0x1ad0 fs/ext4/super.c:3770 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295