From: "Chang S. Bae" <chang.seok.bae@intel.com>
To: pbonzini@redhat.com, seanjc@google.com
Cc: kvm@vger.kernel.org, x86@kernel.org,
linux-kernel@vger.kernel.org, chao.gao@intel.com,
chang.seok.bae@intel.com
Subject: [PATCH v4 10/21] KVM: VMX: Refactor register index retrieval from exit qualification
Date: Tue, 12 May 2026 01:14:51 +0000 [thread overview]
Message-ID: <20260512011502.53072-11-chang.seok.bae@intel.com> (raw)
In-Reply-To: <20260512011502.53072-1-chang.seok.bae@intel.com>
Introduce a helper to extract the register index from the VMX exit
qualification field.
In addition to the VMX instruction information field, exit qualification
also encodes a register index. This field will expand into the previously
reserved bit for extended register IDs. This refactoring will simplify
the extended register handling without code duplication.
Since the VMCS exit qualification is cached in VCPU state, the helper can
reference it efficiently via vmx_get_exit_qual().
No functional change intended.
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
---
arch/x86/kvm/vmx/nested.c | 2 +-
arch/x86/kvm/vmx/vmx.c | 2 +-
arch/x86/kvm/vmx/vmx.h | 5 +++++
3 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index bf2fe6a034aa..cc804a843e76 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -6345,7 +6345,7 @@ static bool nested_vmx_exit_handled_cr(struct kvm_vcpu *vcpu,
switch ((exit_qualification >> 4) & 3) {
case 0: /* mov to cr */
- reg = (exit_qualification >> 8) & 15;
+ reg = vmx_get_exit_qual_reg(vcpu);
val = kvm_register_read(vcpu, reg);
switch (cr) {
case 0:
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 10724b7fd405..f13d56bc32d1 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -5670,7 +5670,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
exit_qualification = vmx_get_exit_qual(vcpu);
cr = exit_qualification & 15;
- reg = (exit_qualification >> 8) & 15;
+ reg = vmx_get_exit_qual_reg(vcpu);
switch ((exit_qualification >> 4) & 3) {
case 0: /* mov to cr */
val = kvm_register_read(vcpu, reg);
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 345b10d28231..f71ae8d2c338 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -323,6 +323,11 @@ static __always_inline unsigned long vmx_get_exit_qual(struct kvm_vcpu *vcpu)
return vt->exit_qualification;
}
+static inline int vmx_get_exit_qual_reg(struct kvm_vcpu *vcpu)
+{
+ return (vmx_get_exit_qual(vcpu) >> 8) & 0xf;
+}
+
static __always_inline u32 vmx_get_intr_info(struct kvm_vcpu *vcpu)
{
struct vcpu_vt *vt = to_vt(vcpu);
--
2.51.0
next prev parent reply other threads:[~2026-05-12 1:40 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-12 1:14 [PATCH v4 00/21] KVM: x86: Enable APX for guests Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 01/21] KVM: VMX: Macrofy GPR swapping in __vmx_vcpu_run() Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 02/21] KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run() Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 03/21] KVM: SEV: Macrofy GPR swapping in __svm_sev_es_vcpu_run() Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 04/21] KVM: x86: Extend VCPU registers for EGPRs Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 05/21] KVM: VMX: Save guest EGPRs in VCPU cache Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 06/21] x86/fpu: Ignore APX when copying from/to guest FPU Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 07/21] KVM: x86: Support APX state for XSAVE ABI Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 08/21] KVM: VMX: Refactor VMX instruction information access Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 09/21] KVM: VMX: Refactor instruction information decoding Chang S. Bae
2026-05-12 1:14 ` Chang S. Bae [this message]
2026-05-12 1:14 ` [PATCH v4 11/21] KVM: VMX: Support instruction information extension Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 12/21] KVM: nVMX: Propagate the extended instruction info field Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 13/21] KVM: x86: Support EGPR accessing and tracking for emulator Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 14/21] KVM: x86: Handle EGPR index and REX2-incompatible opcodes Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 15/21] KVM: x86: Support REX2-prefixed opcode decode Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 16/21] KVM: x86: Reject EVEX-prefixed instructions Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 17/21] KVM: x86: Guard valid XCR0.APX settings Chang S. Bae
2026-05-12 1:14 ` [PATCH v4 18/21] KVM: x86: Expose APX foundation feature to guests Chang S. Bae
2026-05-12 1:15 ` [PATCH v4 19/21] KVM: x86: Expose APX sub-features " Chang S. Bae
2026-05-12 1:15 ` [PATCH v4 20/21] KVM: x86: selftests: Add APX state and ABI test Chang S. Bae
2026-05-12 1:15 ` [PATCH v4 21/21] KVM: x86: selftests: Add APX state handling and XCR0 sanity checks Chang S. Bae
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