On 2/25/26 10:37, Jan Beulich wrote: > On 25.02.2026 00:12, Ariadne Conill wrote: >> From: Steven Noonan <[email protected]> >> >> If we just use the host's BAR addresses, the domU might not attempt to >> reconfigure the BAR ranges and may never try to map them with the IOMMU. >> Zeroing them ensures the guest kernel knows the BARs are not configured >> and needs to make its own choices about where to map the BARs. > > Yet for this, don't we first need to expose a full topology to the guest, > i.e. at least a host bridge, and maybe further bridges? While we eventually do want to expose (a) virtual bridge(s) to vPCI domUs (this work is currently in development), I don't think it's pre-requisite for the code change herein: clearly, leaking host BAR addresses to domUs isn't right, and there's no need to wait to address that.
With that said, the commit title/description don't align well with the code change. Assuming we want to move the code change forward, for v2 of the patch I suggest dropping the 2nd half of the title, and reworking the commit description to focus on describing the code change at hand and less on what the domU might do.
