On Wed, Nov 29, 2017 at 11:57:30 +0100, Michal Privoznik wrote: > On 11/28/2017 02:51 PM, Ján Tomko wrote: > > For implicit controllers, we do not format user aliases on the command > > line so we provide a translation between the user alias and the qemu > > alias. > > > > However for pci-root controllers, the logic determining whether to use > > 'pci' or 'pci.0' depends on: > > * domain architecture > > * machine type > > * QEMU version (for PPC) > > > > Since we do not store the QEMU version in status XML and as of > > commit 5b783379 we no longer have the QEMU_CAPS_PCI_MULTIBUS > > capability formatted there either, we can only rely on the alias > > of the controller formatted there. > > > > Forbid user aliases for the implicit pci-root controllers so that > > we retain this information. > > > > This allows us to drop the call to virQEMUCapsHasPCIMultiBus, > > and fixing hotplug after daemon restart, since virQEMUCapsHasPCIMultiBus > > relies on qemuCaps->arch which is not filled out by reading > > the status XML either. > > > > Partially reverts commit 937f3195 which added the user alias -> > > qemu alias mapping for implicit PCI controllers. > > > > https://bugzilla.redhat.com/show_bug.cgi?id=1518148 > > --- > > > > While we cannot reliably map user aliases to qemu aliases in > > every corner case, I am not sure where to draw the line. > > > > For x86_64, HasPCIMultiBus could be fixed by using def->os.arch instead > > of qemuCaps->arch. So only PPC is unfixable, but this looked like the option > > with the least amount of exceptions. > > > > src/conf/domain_conf.c | 3 +-- > > src/conf/domain_conf.h | 2 ++ > > src/qemu/qemu_command.c | 16 +++++-------- > > src/qemu/qemu_domain.c | 26 +++++++++++++++++++++- > > .../qemuxml2argvdata/qemuxml2argv-user-aliases.xml | 4 +--- > > 5 files changed, 35 insertions(+), 16 deletions(-) > > I'm not a fan of this. If virQEMUCapsHasPCIMultiBus() returns different > results before and after libvirtd is restarted than it will bite us > again in the future. While you're fixing one instance of the bug, the > bug itself is still present. I suggest we extend our status XML to > contain all the info needed so that we can make right decision > regardless of how many times libvirtd is restarted. Which would break any running domains, because they won't have the right info there... Jirka -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
