KVM: s390: Sanitize fpc registers for KVM_SET_FPU

(cherry picked from commit 851755871c1f3184f4124c466e85881f17fa3226)

commit 7eef87dc99e419b1cc051e4417c37e4744d7b661 (KVM: s390: fix
register setting) added a load of the floating point control register
to the KVM_SET_FPU path. Lets make sure that the fpc is valid.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index d1c4457..d3cb86c 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -418,7 +418,7 @@ int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
        memcpy(&vcpu->arch.guest_fpregs.fprs, &fpu->fprs, sizeof(fpu->fprs));
-       vcpu->arch.guest_fpregs.fpc = fpu->fpc;
+       vcpu->arch.guest_fpregs.fpc = fpu->fpc & FPC_VALID_MASK;
        restore_fp_regs(&vcpu->arch.guest_fpregs);
        return 0;
 }