Re: Cannot boot PVH dom0 with big initrd

[Jan Beulich <jbeulich@suse.com>]

On 13.02.2026 05:02, Marek Marczykowski-Górecki wrote:
> After fixing the xhci crash, I hit another issue - booting with 236MB
> initrd doesn't work, I get:
> 
>     (XEN) [    3.151856] *** Building a PVH Dom0 ***
>     ...
>     (XEN) [    3.593940] Unable to allocate memory with order 0!
>     (XEN) [    3.597110] Failed to setup Dom0 physical memory map
>     (XEN) [    3.599884] 
>     (XEN) [    3.602482] ****************************************
>     (XEN) [    3.605272] Panic on CPU 0:
>     (XEN) [    3.607928] Could not construct d0
>     (XEN) [    3.610692] ****************************************
>     (XEN) [    3.613463] 
>     (XEN) [    3.616035] Reboot in five seconds...
>     (XEN) [    8.626565] Resetting with ACPI MEMORY or I/O RESET_REG.
> 
> Full console log: https://gist.github.com/marmarek/c9dbc87bf07b76f2899781755762f565
> 
> If I skip initrd, then it boots just fine (but dom0 is not happy about
> that). 164MB initrd failed too, but 13MB started ok.
> Just in case, I tried skipping XHCI console, but it didn't change
> anything.

You may want to give [1] a try, minimally up to patch 11 (patches 01
and 02 are unrelated, so could be omitted as well).

> Interestingly, this appear to have worked on Xen 4.19.3.

If so, then - judging from the changes which needed making - only out of
luck.

Jan

[1] https://lists.xen.org/archives/html/xen-devel/2026-10/msg00491.html