On Wed, Jul 31, 2024 at 12:36:43 +0200, Boris Fiuczynski wrote: > Migrations of S390 domains from hosts with QEMU supporting ACPI and a > libvirt version prior 9.1.0 fail when the destination host runs a QEMU > not supporting ACPI and a libvirt version 9.1.0 or older. Actually S390 > never supported ACPI but domains were allowed to have the feature ACPI > enabled and it was silently tolerated. To allow migration from libvirt > versions prior 9.1.0 which allowed the ACPI feature to be used on S390 > tolerate ACPI by setting it to absent if specified and QEMU does not > support it. > > Resolves: https://issues.redhat.com/browse/RHEL-49516 > Signed-off-by: Boris Fiuczynski <fiuczy@xxxxxxxxxxxxx> > --- > src/qemu/qemu_domain.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) I'll be posting very soon a version that adds more explanation and has tests so please have a look at that one. It does effectively the same thing to hack around the broken s390 configs ... > > diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c > index 198ab99aef..fbc336ac66 100644 > --- a/src/qemu/qemu_domain.c > +++ b/src/qemu/qemu_domain.c > @@ -4499,6 +4499,16 @@ qemuDomainDefEnableDefaultFeatures(virDomainDef *def, ... but in a more appropriate location. > * capabilities, we still want to enable this */ > def->features[VIR_DOMAIN_FEATURE_GIC] = VIR_TRISTATE_SWITCH_ON; > } > + > + /* To support migration from libvirt versions prio 9.1.0 which allowed > + * the ACPI feature to be used on S390 tolerate ACPI by setting it to > + * absent if specified and QEMU does not support it */ ... also explaining that the configs users were providing were broken the whole time and also that some other arches may suffer from the same problem but are deliberately not fixed. > + if (ARCH_IS_S390(def->os.arch) && > + def->features[VIR_DOMAIN_FEATURE_ACPI] != VIR_TRISTATE_SWITCH_ABSENT && > + virQEMUCapsMachineSupportsACPI(qemuCaps, def->virtType, def->os.machine) == VIR_TRISTATE_BOOL_NO) { > + VIR_DEBUG("Tolerate ACPI on S390 by removing the ACPI feature"); > + def->features[VIR_DOMAIN_FEATURE_ACPI] = VIR_TRISTATE_SWITCH_ABSENT; > + } > } > > > -- > 2.45.0 >
