The issue is described at https://lore.kernel.org/xen-devel/3a8f54cf631e0342b144935950c853d1884a7eac.1680752649.git-series.marmarek@invisiblethingslab.com/

Xen 4.17 crashes the domain on write to MSI-X page. Upcoming fix for
that coincides with re-enabling MSI-X support with HVM, so before
writing, check if MSI-X is enabled.

Fixes QubesOS/qubes-issues#8339