On 06.11.25 14:15, Jan Beulich wrote:> On 24.09.2025 09:59, Mykyta Poturai wrote: >> From: Stefano Stabellini <[email protected]> >> >> has_vpci_bridge is a macro to check if the domain is a domU or is dom0 >> with vPCI (pci-scan=yes) enabled. > > Hmm. Why would DomU-s, now and forever, not have (virtual) bridges? Wasn't them > gaining (virtual) bridges actually the longer-term plan? >
Seems like there is a misunderstanding here. Indeed it is the plan for DomUs to have virtual bridges and this check is designed to differentiate two categories of domains. 1. All DomUs + Dom0 with the virtual bridge. 2. Dom0 with HW bridge. I will try to rephrase the commit message to be more clear. >> @@ -866,7 +866,7 @@ int vpci_init_header(struct pci_dev *pdev) >> struct vpci_header *header = &pdev->vpci->header; >> struct vpci_bar *bars = header->bars; >> int rc; >> - bool is_hwdom = is_hardware_domain(pdev->domain); >> + bool is_hwdom = !has_vpci_bridge(pdev->domain); >> >> ASSERT(rw_is_write_locked(&pdev->domain->pci_lock)); > > For none of the changes (also further ones) it is clear (to me) why the > substitution is (logically) correct. For this last instance the variable > name also ends up wrong after the replacement. >> Jan The general logic for this change is that before it we assumed that hwdom always uses HW bridge. Now it is not always true and hwdom can also use a virtual bridge, so it needs to be treated the same way as DomUs are. You also mentioned on a previous series > Here and perhaps everywhere else I wonder: Is this really an appropriately > named predicate for the purpose / context? Maybe you have some ideas of a better name? From what I came up with this seems like the best one. -- Mykyta
