It seems the patch you mentioned was merged to upstream Linux here:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i
d=71472fa9c52b1da27663c275d416d8654b905f05
and then reverted/removed here:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i
d=896d81fefe5d1919537db2c2150ab6384e4a6610
Do you know if there has been proper/fixed patch after that? has it been merged to upstream Linux kernel already?
Interesting! I didn't come across that when digging into this.
It looks like this hasn't been followed up on at all since April: https://lists.gt.net/engine?list=linux;do=search_results;search_type=AND;sea rch_forum=forum_1;search_string=ldisc%20reopened&sb=post_time
Currently I've got ~40 dom0's running with the patch on 4.9.44-39 and it's resolved all stability issues, previously I was seeing multiple crashes a week.
Cheers, Nathan