7 On 03/06/2018 02:29 PM, Cornelia Huck wrote: > On Tue, 6 Mar 2018 14:27:58 +0100 > David Hildenbrand <david@xxxxxxxxxx> wrote: > >> Even if we don't have extended SCA support, we can have more than 64 CPUs >> if we don't enable any HW features that might use the SCA entries. >> >> Now, this works just fine, but we missed a return, which is why we >> would actually store the SCA entries. If we have more than 64 CPUs, this >> means writing outside of the basic SCA - bad. >> >> Let's fix this. This allows > 64 CPUs when running nested (under vSIE) >> without random crashes. >> >> Fixes: a6940674c384 ("KVM: s390: allow 255 VCPUs when sca entries aren't used") > > cc: stable? yes. >> Reported-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> >> Tested-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> >> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> >> --- >> arch/s390/kvm/kvm-s390.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >> index 77d7818130db..321bfbc67d3d 100644 >> --- a/arch/s390/kvm/kvm-s390.c >> +++ b/arch/s390/kvm/kvm-s390.c >> @@ -2146,6 +2146,7 @@ static void sca_add_vcpu(struct kvm_vcpu *vcpu) >> /* we still need the basic sca for the ipte control */ >> vcpu->arch.sie_block->scaoh = (__u32)(((__u64)sca) >> 32); >> vcpu->arch.sie_block->scaol = (__u32)(__u64)sca; >> + return; >> } >> read_lock(&vcpu->kvm->arch.sca_lock); >> if (vcpu->kvm->arch.use_esca) { > > Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> Thanks applied and queued for master. -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html