On Fri, Sep 19, 2025 at 07:00:17PM +0200, Peter Krempa wrote:
On Fri, Sep 19, 2025 at 10:34:39 -0500, Andrea Bolognani wrote:
On Fri, Sep 19, 2025 at 11:39:05AM +0200, Peter Krempa wrote:
On Tue, Aug 19, 2025 at 18:22:34 +0200, Andrea Bolognani via Devel wrote:
+++ b/tests/qemuxmlconfdata/armv7l-versatilepb-minimal.armv7l-latest.args @@ -26,7 +26,7 @@ XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain--1-armv7ltest/.config \ -rtc base=utc \ -no-shutdown \ -boot strict=on \ --device '{"driver":"pci-ohci","id":"usb","bus":"pci","addr":"0x1"}' \ +-device '{"driver":"qemu-xhci","id":"usb","bus":"pci","addr":"0x1"}' \
This change seems to have happened also in code paths not allowing ABI update at least according to the filename.
It only affects domains for which a model was not picked in the past. So effectively only new domains, regardless of the flags. Existing domains will keep using whatever model they're configured to use.
Beware that we historically considered also virDomainCreateXML (transient wit possibly not fully filled XML) to be compatible across runs. I know that we already didn't obey this in some cases but we should consider this every time.
Fair point. I feel that the actual impact on users is going to be basically zero in this case, so I'm inclined to focus more on reaching well-defined, reasonably consistent behavior across the board that's implemented in a maintainable manner rather than necessarily preserving the existing behavior for all niche machine types in all niche scenarios.
Especially in case of these limited boards the hardware you'd normally built in will certainly not be XHCI
I'd be fine using pci-ohci as the baseline for everything that is not one of the "explicitly supported" machines (that is, virt across architectures, i440fx and q35 on x86, pseries on ppc64 and s390-ccw-virtio on s390x). That's pretty much exactly how things look once this series has been applied. In this case, however, I'm simply extending the existing default for 64-bit Arm machines to 32-bit ones. I don't think it makes sense to differentiate the model based on the number of bits - QEMU doesn't. So either we downgrade the 64-bit machines or upgrade the 32-bit ones. Looking at what QEMU does, the default for this machine type is pci-ohci. So I'd say let's go with that. -- Andrea Bolognani / Red Hat / Virtualization