On 10/23/23 06:27, Anthony PERARD wrote: > On Mon, Oct 09, 2023 at 03:57:44PM -0400, Stewart Hildebrand wrote: >> Select HAS_VPCI_GUEST_SUPPORT in Kconfig for enabling vPCI in domUs. >> >> Set the pci flags in xen_arch_domainconfig to enable vPCI if a pci device has >> been specified in the xl domain config file. >> >> Signed-off-by: Stewart Hildebrand <stewart.hildebr...@amd.com> >> --- >> As the tag implies, this patch is not intended to be merged (yet). >> >> Note that CONFIG_HAS_VPCI_GUEST_SUPPORT is not currently used in the upstream >> code base. It will be used by the vPCI series [1]. This patch is intended to >> be >> merged as part of the vPCI series. I'll coordinate with Volodymyr to include >> this in the vPCI series or resend afterwards. Meanwhile, I'll include it here >> until the Kconfig and xen_arch_domainconfig prerequisites have been >> committed. >> >> v2->v3: >> * set pci flags in toolstack >> >> v1->v2: >> * new patch >> >> [1] >> https://lists.xenproject.org/archives/html/xen-devel/2023-08/msg02361.html >> --- >> tools/libs/light/libxl_arm.c | 3 +++ >> xen/arch/arm/Kconfig | 1 + > > Can we have two different patch? One for the hypervisor, one for the > tools.
Yes. > Or does the both depends on each other, somehow? They will both be needed for enabling vPCI in a domU on ARM with assigned PCI device(s). > > Is guest creation going to fails if we set XEN_DOMCTL_CONFIG_PCI_VPCI > without HAS_VPCI_GUEST_SUPPORT ? No, currently the guest will still run, it just won't be able to probe any assigned PCI devices. > > Is the guest is going to fail to run, or fail at creation if the > hypervisor HAS_VPCI_GUEST_SUPPORT, but we didn't set > XEN_DOMCTL_CONFIG_PCI_VPCI? Assuming num_pcidevs > 0, the guest will be created but fail to boot as it will try to access the vPCI configuration space, but it will trap and panic. In both cases, I think I can do more on the hypervisor side to check for an invalid configuration and refuse the domain creation with a helpful error message. In either case, if a user does not try to assign a PCI device (i.e. num_pcidevs == 0), then the guest will run fine. > > Thanks, > > -- > Anthony PERARD
