[PATCH 05/15] KVM: VMX: Add and use X86_CR4_PDPTR_BITS when !enable_ept

Lai Jiangshan
2021-11-08T12:44:48Z

From: Lai Jiangshan <laijs@linux.alibaba.com>

In set_cr4_guest_host_mask(), all cr4 pdptr bits are already set to be
intercepted in an unclear way.

Add X86_CR4_PDPTR_BITS to make it clear and self-documented.

No functionality changed.

Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
---
arch/x86/kvm/kvm_cache_regs.h | 1 +
arch/x86/kvm/vmx/vmx.c | 4 +++-
arch/x86/kvm/x86.c | 4 +---
3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 8fe036efa654..592f9eb9753b 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -10,6 +10,7 @@
| X86_CR4_OSXMMEXCPT | X86_CR4_PGE | X86_CR4_TSD | X86_CR4_FSGSBASE)

#define X86_CR4_TLB_BITS (X86_CR4_PGE | X86_CR4_PCIDE | X86_CR4_PAE | X86_CR4_SMEP)
+#define X86_CR4_PDPTR_BITS (X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_SMEP)

#define BUILD_KVM_GPR_ACCESSORS(lname, uname) \
static __always_inline unsigned long kvm_##lname##_read(struct kvm_vcpu *vcpu)\
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 1795702dc6de..d94e51e9c08f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4106,8 +4106,10 @@ void set_cr4_guest_host_mask(struct vcpu_vmx *vmx)

vcpu->arch.cr4_guest_owned_bits = KVM_POSSIBLE_CR4_GUEST_BITS &
~vcpu->arch.cr4_guest_rsvd_bits;
- if (!enable_ept)
+ if (!enable_ept) {
vcpu->arch.cr4_guest_owned_bits &= ~X86_CR4_TLB_BITS;
+ vcpu->arch.cr4_guest_owned_bits &= ~X86_CR4_PDPTR_BITS;
+ }
if (is_guest_mode(&vmx->vcpu))
vcpu->arch.cr4_guest_owned_bits &=
~get_vmcs12(vcpu)->cr4_guest_host_mask;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 034c233ea5a1..b92d4241b4d9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1052,8 +1052,6 @@ EXPORT_SYMBOL_GPL(kvm_post_set_cr4);
int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
{
unsigned long old_cr4 = kvm_read_cr4(vcpu);
- unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE |
- X86_CR4_SMEP;

if (!kvm_is_valid_cr4(vcpu, cr4))
return 1;
@@ -1064,7 +1062,7 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
if ((cr4 ^ old_cr4) & X86_CR4_LA57)
return 1;
} else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
- && ((cr4 ^ old_cr4) & pdptr_bits)
+ && ((cr4 ^ old_cr4) & X86_CR4_PDPTR_BITS)
&& !load_pdptrs(vcpu, vcpu->arch.walk_mmu,
kvm_read_cr3(vcpu)))
return 1;
--
2.19.1.6.gb485710b