Re: [Xen-devel] [PATCH v2] x86/hvmloader: round up memory BAR size to 4K

[Jan Beulich <jbeulich@xxxxxxxx>]

On 17.01.2020 12:08, Roger Pau Monne wrote:
> When placing memory BARs with sizes smaller than 4K multiple memory
> BARs can end up mapped to the same guest physical address, and thus
> won't work correctly.

Thinking about it again, aren't you fixing one possible case by
breaking the opposite one: What you fix is when the two distinct
BARs (of the same or different devices) map to distinct MFNs
(which would have required a single GFN to map to both of these
MFNs). But don't you, at the same time, break the case of two
BARs (perhaps, but not necessarily, of the same physical device)
mapping both to the same MFN, i.e. requiring to have two distinct
GFNs map to one MFN? (At least for the moment I can't see a way
for hvmloader to distinguish the two cases.)

Jan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel