[PATCH 06/10] KVM: emulate: add get_xcr callback

Paolo Bonzini
2025-11-14T00:36:44Z

This will be necessary in order to check whether AVX is enabled.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/kvm_emulate.h | 1 +
arch/x86/kvm/x86.c | 9 +++++++++
2 files changed, 10 insertions(+)

diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index 83af019620e3..5f9d69c64cd5 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -237,6 +237,7 @@ struct x86_emulate_ops {
bool (*is_smm)(struct x86_emulate_ctxt *ctxt);
int (*leave_smm)(struct x86_emulate_ctxt *ctxt);
void (*triple_fault)(struct x86_emulate_ctxt *ctxt);
+ int (*get_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 *xcr);
int (*set_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr);

gva_t (*get_untagged_addr)(struct x86_emulate_ctxt *ctxt, gva_t addr,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c9c2aa6f4705..cfce7c120215 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8842,6 +8842,14 @@ static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt)
kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt));
}

+static int emulator_get_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 *xcr)
+{
+ if (index != XCR_XFEATURE_ENABLED_MASK)
+ return 1;
+ *xcr = emul_to_vcpu(ctxt)->arch.xcr0;
+ return 0;
+}
+
static int emulator_set_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr)
{
return __kvm_set_xcr(emul_to_vcpu(ctxt), index, xcr);
@@ -8914,6 +8922,7 @@ static const struct x86_emulate_ops emulate_ops = {
.is_smm = emulator_is_smm,
.leave_smm = emulator_leave_smm,
.triple_fault = emulator_triple_fault,
+ .get_xcr = emulator_get_xcr,
.set_xcr = emulator_set_xcr,
.get_untagged_addr = emulator_get_untagged_addr,
.is_canonical_addr = emulator_is_canonical_addr,
--
2.43.5