syzbot

INFO: task syz-executor.4:11534 blocked for more than 143 seconds.
      Not tainted 5.15.111-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:    0 pid:11534 ppid:  4012 flags:0x00000009
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0xf10/0x1e38 kernel/sched/core.c:6372
 schedule+0x11c/0x1c8 kernel/sched/core.c:6455
 io_schedule+0x8c/0x194 kernel/sched/core.c:8472
 bit_wait_io+0x1c/0xac kernel/sched/wait_bit.c:209
 __wait_on_bit_lock+0xcc/0x1f0 kernel/sched/wait_bit.c:90
 out_of_line_wait_on_bit_lock+0x194/0x21c kernel/sched/wait_bit.c:117
 wait_on_bit_lock_io include/linux/wait_bit.h:208 [inline]
 __lock_buffer fs/buffer.c:69 [inline]
 lock_buffer+0x108/0x174 include/linux/buffer_head.h:402
 __sync_dirty_buffer+0x6c/0x350 fs/buffer.c:3144
 sync_dirty_buffer+0x24/0x34 fs/buffer.c:3170
 __ext4_handle_dirty_metadata+0x198/0x740 fs/ext4/ext4_jbd2.c:381
 ext4_convert_inline_data_nolock+0x680/0xc18 fs/ext4/inline.c:1262
 ext4_convert_inline_data+0x390/0x53c fs/ext4/inline.c:2045
 ext4_fallocate+0x124/0x1cb4 fs/ext4/extents.c:4705
 vfs_fallocate+0x478/0x5b4 fs/open.c:308
 ioctl_preallocate+0x2a0/0x34c fs/ioctl.c:294
 do_vfs_ioctl+0x1d00/0x2a38 fs/ioctl.c:853
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0xe4/0x1c8 fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffff800014aa19e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:268
3 locks held by kworker/u4:3/153:
2 locks held by getty/3725:
 #0: ffff0000d319a098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001a27b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1200 drivers/tty/n_tty.c:2147
2 locks held by syz-executor.2/4021:
 #0: ffff0000cbc64918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912
 #1: ffff0000cbc5c468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa8/0x9b8 drivers/block/loop.c:1365
3 locks held by syz-executor.4/11534:
 #0: ffff00010eb18460 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2966 [inline]
 #0: ffff00010eb18460 (sb_writers#3){.+.+}-{0:0}, at: vfs_fallocate+0x404/0x5b4 fs/open.c:307
 #1: ffff0000d4cd21d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff0000d4cd21d8 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_fallocate+0x11c/0x1cb4 fs/ext4/extents.c:4704
 #2: ffff0000d4cd1eb0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline]
 #2: ffff0000d4cd1eb0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_convert_inline_data+0x2dc/0x53c fs/ext4/inline.c:2043
1 lock held by udevd/12596:
 #0: ffff0000cbc64918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x12c/0x89c block/bdev.c:817
1 lock held by syz-executor.5/16378:
 #0: ffff000121600120 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1649 [inline]
 #0: ffff000121600120 (sk_lock-AF_INET6){+.+.}-{0:0}, at: mptcp_stream_connect+0x68/0x958 net/mptcp/protocol.c:3292

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