@pandusen, I understand your frustration, but please focus on the content, not the person. Also, note that the request for dmesg output came from @MajorP93. @john.c, if you use a tool, please check its commands before posting, and try to keep your posts shorter. On the content: step 1 of @john.c's advice is xen-cmdline --set-xen "pci=realloc", and that part is wrong. AFAIK, Xen's pci= option only accepts serr, perr and quirks (Xen command line docs); realloc isn't a valid Xen option. pci=realloc is a Linux kernel option, right? It's okay to be wrong; I often am too. The important thing is not to be overly assertive when you're not sure you have the right answer. Teddy's answer is sound, which is why I marked this thread as solved. However, the thread isn't locked, so it remains open for the Arc and ReBAR follow-up. Thanks, folks, let's keep a friendly and helpful atmosphere.