There is a new pull request by ahesford against master on the void-packages repository

https://github.com/ahesford/void-packages lxc
https://github.com/void-linux/void-packages/pull/27352

lxc: fix config parsing with linux5.10
When upgrading to `linux5.10`, I noticed that LXC failed to parse configs, complaining about a failure in `sendfile(2)`. I was unable to start existing containers or create new ones. Upstream commit lxc/lxc@26dffd825842edf019bc17da24a6809ed51c048c already addresses this, dropping use of `sendfile` in the config parser altogether.

@CameronNemo, do you have any objections to including this patch?

A patch file from https://github.com/void-linux/void-packages/pull/27352.patch is attached