On Wed, 7 Jun 2023 10:26:59 +0200 Philippe Mathieu-Daudé <phi...@linaro.org> wrote:
> On 7/6/23 04:49, Suravee Suthikulpanit wrote: > > Since KVM_MAX_VCPUS is currently defined to 1024 for x86 as shown in > > arch/x86/include/asm/kvm_host.h, update QEMU limits to the same number. > > > > In case KVM could not support the specified number of vcpus, QEMU would > > return the following error message: > > > > qemu-system-x86_64: kvm_init_vcpu: kvm_get_vcpu failed (xxx): Invalid > > argument > > Odd, we already check the upper limit with KVM_CAP_NR_VCPUS. > See in kvm_init(): > > /* check the vcpu limits */ > soft_vcpus_limit = kvm_recommended_vcpus(s); > hard_vcpus_limit = kvm_max_vcpus(s); > > When testing your series I get: > > qemu-system-x86_64: -accel kvm: warning: Number of SMP cpus requested > (1024) exceeds the recommended cpus supported by KVM (710) Also do not forget about TCG where KVM accel is not even in the picture. > $ uname -srvp > Linux 5.15.0-71-generic #78-Ubuntu SMP Tue Apr 18 09:00:29 UTC 2023 x86_64 > > > Also, keep max_cpus at 288 for machine version 8.0 and older. > > > > Cc: Igor Mammedov <imamm...@redhat.com> > > Cc: Daniel P. Berrangé <berra...@redhat.com> > > Cc: Michael S. Tsirkin <m...@redhat.com> > > Cc: Julia Suvorova <jus...@redhat.com> > > Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com> > > --- > > hw/i386/pc_q35.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) >
