Comment 10 for bug 1767992

Kernel from https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1767992/comments/8 solved my issues.

For reproduce on 4.15.0-50-generic
Make new raid-10, add some io fio/dd, unpack anaconda archives(lol), after minute or two deadlocked

[Mon Jul 15 19:31:11 2019] Workqueue: md md_submit_flush_data
[Mon Jul 15 19:31:11 2019] Call Trace:
[Mon Jul 15 19:31:11 2019] __schedule+0x291/0x8a0
[Mon Jul 15 19:31:11 2019] ? __switch_to_asm+0x34/0x70
[Mon Jul 15 19:31:11 2019] ? __switch_to_asm+0x40/0x70
[Mon Jul 15 19:31:11 2019] schedule+0x2c/0x80
[Mon Jul 15 19:31:11 2019] wait_barrier+0x146/0x1a0 [raid10]
[Mon Jul 15 19:31:11 2019] ? wait_woken+0x80/0x80
[Mon Jul 15 19:31:11 2019] raid10_write_request+0x77/0x950 [raid10]
[Mon Jul 15 19:31:11 2019] ? r10bio_pool_alloc+0x24/0x30 [raid10]
[Mon Jul 15 19:31:11 2019] ? mempool_alloc+0x71/0x190
[Mon Jul 15 19:31:11 2019] ? md_write_start+0xf4/0x210
[Mon Jul 15 19:31:11 2019] ? default_wake_function+0x12/0x20
[Mon Jul 15 19:31:11 2019] ? autoremove_wake_function+0x12/0x40
[Mon Jul 15 19:31:11 2019] raid10_make_request+0xcc/0x140 [raid10]
[Mon Jul 15 19:31:11 2019] md_handle_request+0x126/0x1a0
[Mon Jul 15 19:31:11 2019] md_submit_flush_data+0x54/0x70
[Mon Jul 15 19:31:11 2019] process_one_work+0x1de/0x410
[Mon Jul 15 19:31:11 2019] worker_thread+0x32/0x410
[Mon Jul 15 19:31:11 2019] kthread+0x121/0x140
[Mon Jul 15 19:31:11 2019] ? process_one_work+0x410/0x410
[Mon Jul 15 19:31:11 2019] ? kthread_create_worker_on_cpu+0x70/0x70
[Mon Jul 15 19:31:11 2019] ret_from_fork+0x35/0x40