!kvm_cpu_has(feature.anti_feature);
}
+static __always_inline uint64_t kvm_cpu_supported_xcr0(void)
+{
+ if (!kvm_cpu_has_p(X86_PROPERTY_SUPPORTED_XCR0_LO))
+ return 0;
+
+ return kvm_cpu_property(X86_PROPERTY_SUPPORTED_XCR0_LO) |
+ ((uint64_t)kvm_cpu_property(X86_PROPERTY_SUPPORTED_XCR0_HI) << 32);
+}
+
static inline size_t kvm_cpuid2_size(int nr_entries)
{
return sizeof(struct kvm_cpuid2) +
int main(int argc, char *argv[])
{
+ uint64_t *xstate_bv, saved_xstate_bv;
vm_vaddr_t nested_gva = 0;
struct kvm_cpuid2 empty_cpuid = {};
struct kvm_regs regs1, regs2;
* allow KVM_SET_XSAVE regardless of guest CPUID. Manually
* load only XSAVE state, MSRs in particular have a much more
* convoluted ABI.
+ *
+ * Load two versions of XSAVE state: one with the actual guest
+ * XSAVE state, and one with all supported features forced "on"
+ * in xstate_bv, e.g. to ensure that KVM allows loading all
+ * supported features, even if something goes awry in saving
+ * the original snapshot.
*/
+ xstate_bv = (void *)&((uint8_t *)state->xsave->region)[512];
+ saved_xstate_bv = *xstate_bv;
+
vcpuN = __vm_vcpu_add(vm, vcpu->id + 1);
vcpu_xsave_set(vcpuN, state->xsave);
+ *xstate_bv = kvm_cpu_supported_xcr0();
+ vcpu_xsave_set(vcpuN, state->xsave);
vcpu_init_cpuid(vcpuN, &empty_cpuid);
vcpu_xsave_set(vcpuN, state->xsave);
+ *xstate_bv = saved_xstate_bv;
+ vcpu_xsave_set(vcpuN, state->xsave);
kvm_x86_state_cleanup(state);