Dear Maintainer,

After upgrading to Linux 5.15 random hangs have been reported. After debugging
the issue seems to be related to VMAP_STACK so a bug report upstream was
created.

http://lists.infradead.org/pipermail/linux-um/2022-January/002024.html

After disabling VMAP_STACK and testing for more than two weeks no hangs were
reported, so I propose the following fix

https://salsa.debian.org/uml-team/user-mode-linux/-/merge_requests/9