INFO: task kworker/1:4:5837 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:22504 pid:5837 tgid:5837 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: gfs2_recovery gfs2_recover_func Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1848/0x4ec0 kernel/sched/core.c:6872 __schedule_loop kernel/sched/core.c:6954 [inline] schedule+0x165/0x360 kernel/sched/core.c:6969 io_schedule+0x80/0xd0 kernel/sched/core.c:7801 folio_wait_bit_common+0x6b0/0xb80 mm/filemap.c:1323 folio_wait_locked include/linux/pagemap.h:1234 [inline] gfs2_jhead_process_page+0x171/0x650 fs/gfs2/lops.c:469 gfs2_find_jhead+0xcf9/0xe40 fs/gfs2/lops.c:583 gfs2_recover_func+0x5f5/0x1c90 fs/gfs2/recovery.c:459 process_one_work+0x94a/0x15d0 kernel/workqueue.c:3267 process_scheduled_works kernel/workqueue.c:3350 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3431 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.1.1058:10018 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1058 state:D stack:24840 pid:10018 tgid:10014 ppid:5833 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1848/0x4ec0 kernel/sched/core.c:6872 __schedule_loop kernel/sched/core.c:6954 [inline] schedule+0x165/0x360 kernel/sched/core.c:6969 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:240 __wait_on_bit+0xb9/0x310 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:67 wait_on_bit include/linux/wait_bit.h:77 [inline] gfs2_recover_journal+0xda/0x140 fs/gfs2/recovery.c:579 init_journal+0x1987/0x2180 fs/gfs2/ops_fstype.c:794 init_inodes+0xdb/0x320 fs/gfs2/ops_fstype.c:844 gfs2_fill_super+0x1aaa/0x2270 fs/gfs2/ops_fstype.c:1254 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1336 vfs_get_tree+0x92/0x2b0 fs/super.c:1752 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3641 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3717 do_mount fs/namespace.c:4040 [inline] __do_sys_mount fs/namespace.c:4228 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4205 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc0fb190e6a RSP: 002b:00007fc0fbf7de68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc0fbf7def0 RCX: 00007fc0fb190e6a RDX: 0000200000000300 RSI: 0000200000000500 RDI: 00007fc0fbf7deb0 RBP: 0000200000000300 R08: 00007fc0fbf7def0 R09: 0000000002810000 R10: 0000000002810000 R11: 0000000000000246 R12: 0000200000000500 R13: 00007fc0fbf7deb0 R14: 0000000000038046 R15: 0000200000000580 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3b720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3b720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5584: #0: ffff888033be50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5821: #0: ffff88806cd000e0 (&type->s_umount_key#84){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88806cd000e0 (&type->s_umount_key#84){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88806cd000e0 (&type->s_umount_key#84){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff88801c6f8188 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_remove+0x30/0x60 fs/kernfs/dir.c:1549 2 locks held by kworker/1:4/5837: #0: ffff88801afaa548 ((wq_completion)gfs2_recovery){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242 #1: ffffc900045efb80 ((work_completion)(&jd->jd_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243 1 lock held by syz.1.1058/10018: #0: ffff88807c7940e0 (&type->s_umount_key#96/1){+.+.}-{4:4}, at: alloc_super+0x1bb/0x960 fs/super.c:344 6 locks held by kworker/1:2/10305: #0: ffff88801d6dbd48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242 #1: ffffc9000b107b80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243 #2: ffff888027fc8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888027fc8198 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4ef0 drivers/usb/core/hub.c:5899 #3: ffff88804d89d198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #3: ffff88804d89d198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006 #4: ffff888027da4160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #4: ffff888027da4160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x430 drivers/base/dd.c:1006 #5: ffff888035754f98 (&d->usb_mutex){+.+.}-{4:4}, at: az6027_usb_out_op drivers/media/usb/dvb-usb/az6027.c:340 [inline] #5: ffff888035754f98 (&d->usb_mutex){+.+.}-{4:4}, at: az6027_frontend_poweron drivers/media/usb/dvb-usb/az6027.c:834 [inline] #5: ffff888035754f98 (&d->usb_mutex){+.+.}-{4:4}, at: az6027_frontend_attach+0x4b/0x560 drivers/media/usb/dvb-usb/az6027.c:907 2 locks held by kworker/u8:32/10498: #0: ffff88801bfe3948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x841/0x15d0 kernel/workqueue.c:3242 #1: ffffc90003c17b80 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15d0 kernel/workqueue.c:3243 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:336 [inline] watchdog+0xfa9/0xff0 kernel/hung_task.c:499 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 13 f1 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 0a 0c 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c2 RAX: 1ea610e47ff42400 RBX: ffffffff81976627 RCX: 1ea610e47ff42400 RDX: 0000000000000001 RSI: ffffffff8d786e5e RDI: ffffffff8bbf41e0 RBP: ffffffff8dc07ea8 R08: ffff8880b863339b R09: 1ffff110170c6673 R10: dffffc0000000000 R11: ffffed10170c6674 R12: ffffffff8f7da970 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b92660 FS: 0000000000000000(0000) GS:ffff888125ec2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffd325aed8 CR3: 0000000078ae4000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e7/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:758 start_kernel+0x3ac/0x410 init/main.c:1208 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147