Commit 82cc27ef authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
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KVM: s390: Cap KVM_CAP_NR_VCPUS by num_online_cpus() 



KVM_CAP_NR_VCPUS is a legacy advisory value which on other architectures
return num_online_cpus() caped by KVM_CAP_NR_VCPUS or something else
(ppc and arm64 are special cases). On s390, KVM_CAP_NR_VCPUS returns
the same as KVM_CAP_MAX_VCPUS and this may turn out to be a bad
'advice'. Switch s390 to returning caped num_online_cpus() too.

Acked-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: default avatarChristian Borntraeger <borntraeger@linux.ibm.com>
Message-Id: <20211116163443.88707-6-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 37fd3ce1

arch/s390/kvm/kvm-s390.c

+2 −0
Original line number Diff line number Diff line
@@ -585,6 +585,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 
			r = KVM_MAX_VCPUS;

		else if (sclp.has_esca && sclp.has_64bscao)

			r = KVM_S390_ESCA_CPU_SLOTS;

		if (ext == KVM_CAP_NR_VCPUS)

			r = min_t(unsigned int, num_online_cpus(), r);

		break;

	case KVM_CAP_S390_COW:

		r = MACHINE_HAS_ESOP;