From: Tom Lendacky <thomas.lenda...@amd.com>

Currently the nested_ctl variable in the vmcb_control_area structure is
used to indicate nested paging support. The nested paging support field
is actually defined as bit 0 of the this field. In order to support a new
feature flag the usage of the nested_ctl and nested paging support must
be converted to operate on a single bit.

Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com>
---
 arch/x86/include/asm/svm.h |    2 ++
 arch/x86/kvm/svm.c         |    7 ++++---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h
index 14824fc..2aca535 100644
--- a/arch/x86/include/asm/svm.h
+++ b/arch/x86/include/asm/svm.h
@@ -136,6 +136,8 @@ struct __attribute__ ((__packed__)) vmcb_control_area {
 #define SVM_VM_CR_SVM_LOCK_MASK 0x0008ULL
 #define SVM_VM_CR_SVM_DIS_MASK  0x0010ULL
 
+#define SVM_NESTED_CTL_NP_ENABLE       BIT(0)
+
 struct __attribute__ ((__packed__)) vmcb_seg {
        u16 selector;
        u16 attrib;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 9b2de7c..9b59260 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1177,7 +1177,7 @@ static void init_vmcb(struct vcpu_svm *svm)
 
        if (npt_enabled) {
                /* Setup VMCB for Nested Paging */
-               control->nested_ctl = 1;
+               control->nested_ctl |= SVM_NESTED_CTL_NP_ENABLE;
                clr_intercept(svm, INTERCEPT_INVLPG);
                clr_exception_intercept(svm, PF_VECTOR);
                clr_cr_intercept(svm, INTERCEPT_CR3_READ);
@@ -2701,7 +2701,8 @@ static bool nested_vmcb_checks(struct vmcb *vmcb)
        if (vmcb->control.asid == 0)
                return false;
 
-       if (vmcb->control.nested_ctl && !npt_enabled)
+       if ((vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) &&
+           !npt_enabled)
                return false;
 
        return true;
@@ -2776,7 +2777,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
        else
                svm->vcpu.arch.hflags &= ~HF_HIF_MASK;
 
-       if (nested_vmcb->control.nested_ctl) {
+       if (nested_vmcb->control.nested_ctl & SVM_NESTED_CTL_NP_ENABLE) {
                kvm_mmu_unload(&svm->vcpu);
                svm->nested.nested_cr3 = nested_vmcb->control.nested_cr3;
                nested_svm_init_mmu_context(&svm->vcpu);

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