On Mon, May 09, 2022 at 09:12:49AM +0200, Igor Mammedov wrote: > On Wed, 4 May 2022 08:16:39 -0500 > Suravee Suthikulpanit <[email protected]> wrote: > > > This is the maximum number of vCPU supported by > > the AMD x2APIC virtualization. > > > > Signed-off-by: Suravee Suthikulpanit <[email protected]> > > --- > > hw/i386/pc_q35.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c > > index 302288342a..e82b1c690d 100644 > > --- a/hw/i386/pc_q35.c > > +++ b/hw/i386/pc_q35.c > > @@ -357,7 +357,7 @@ static void pc_q35_machine_options(MachineClass *m) > > machine_class_allow_dynamic_sysbus_dev(m, TYPE_INTEL_IOMMU_DEVICE); > > machine_class_allow_dynamic_sysbus_dev(m, TYPE_RAMFB_DEVICE); > > machine_class_allow_dynamic_sysbus_dev(m, TYPE_VMBUS_BRIDGE); > > - m->max_cpus = 288; > > + m->max_cpus = 512; > > Maybe we should bump it to KVM VCPU maximum, > and make sure we error out if asked for combination of > hardware/irqchip is not usable.
In RHEL downstream we currently bump this to 710 CPUs, because you overflow the SMBIOS 2.1 tables at approx 720 CPUs (give/take a little depending on other config options). Going beyond 710 CPUs value requires using the SMBIOS 3 entry point. AFAIK, the x86 machine types still default to SMBIOS 2.1, so that would need changing too. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
