From: Paolo Bonzini pbonzini@redhat.com
Upstream commit bf03d4f9334728bf7c8ffc7de787df48abd6340e.
Checking for 32-bit PAE is quite common around code that fiddles with the PDPTRs. Add a function to compress all checks into a single invocation.
Moving to the common helper also fixes a subtle bug in kvm_set_cr3() where it fails to check is_long_mode() and results in KVM incorrectly attempting to load PDPTRs for a 64-bit guest.
Reviewed-by: Sean Christopherson sean.j.christopherson@intel.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com [sean: backport to 4.x; handle vmx.c split in 5.x, call out the bugfix] Signed-off-by: Sean Christopherson sean.j.christopherson@intel.com --- arch/x86/kvm/vmx.c | 7 +++---- arch/x86/kvm/x86.c | 8 ++++---- arch/x86/kvm/x86.h | 5 +++++ 3 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 6f7b3acdab26..83acaed244ba 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5181,7 +5181,7 @@ static void ept_load_pdptrs(struct kvm_vcpu *vcpu) (unsigned long *)&vcpu->arch.regs_dirty)) return;
- if (is_paging(vcpu) && is_pae(vcpu) && !is_long_mode(vcpu)) { + if (is_pae_paging(vcpu)) { vmcs_write64(GUEST_PDPTR0, mmu->pdptrs[0]); vmcs_write64(GUEST_PDPTR1, mmu->pdptrs[1]); vmcs_write64(GUEST_PDPTR2, mmu->pdptrs[2]); @@ -5193,7 +5193,7 @@ static void ept_save_pdptrs(struct kvm_vcpu *vcpu) { struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
- if (is_paging(vcpu) && is_pae(vcpu) && !is_long_mode(vcpu)) { + if (is_pae_paging(vcpu)) { mmu->pdptrs[0] = vmcs_read64(GUEST_PDPTR0); mmu->pdptrs[1] = vmcs_read64(GUEST_PDPTR1); mmu->pdptrs[2] = vmcs_read64(GUEST_PDPTR2); @@ -12021,8 +12021,7 @@ static int nested_vmx_load_cr3(struct kvm_vcpu *vcpu, unsigned long cr3, bool ne * If PAE paging and EPT are both on, CR3 is not used by the CPU and * must not be dereferenced. */ - if (!is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu) && - !nested_ept) { + if (is_pae_paging(vcpu) && !nested_ept) { if (!load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)) { *entry_failure_code = ENTRY_FAIL_PDPTE; return 1; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6ae8a013af31..b9b87fb75ac0 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -633,7 +633,7 @@ bool pdptrs_changed(struct kvm_vcpu *vcpu) gfn_t gfn; int r;
- if (is_long_mode(vcpu) || !is_pae(vcpu) || !is_paging(vcpu)) + if (!is_pae_paging(vcpu)) return false;
if (!test_bit(VCPU_EXREG_PDPTR, @@ -884,8 +884,8 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) if (is_long_mode(vcpu) && (cr3 & rsvd_bits(cpuid_maxphyaddr(vcpu), 63))) return 1; - else if (is_pae(vcpu) && is_paging(vcpu) && - !load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)) + else if (is_pae_paging(vcpu) && + !load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)) return 1;
kvm_mmu_new_cr3(vcpu, cr3, skip_tlb_flush); @@ -8312,7 +8312,7 @@ static int __set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs) kvm_update_cpuid(vcpu);
idx = srcu_read_lock(&vcpu->kvm->srcu); - if (!is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu)) { + if (is_pae_paging(vcpu)) { load_pdptrs(vcpu, vcpu->arch.walk_mmu, kvm_read_cr3(vcpu)); mmu_reset_needed = 1; } diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 3a91ea760f07..608e5f8c5d0a 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -139,6 +139,11 @@ static inline int is_paging(struct kvm_vcpu *vcpu) return likely(kvm_read_cr0_bits(vcpu, X86_CR0_PG)); }
+static inline bool is_pae_paging(struct kvm_vcpu *vcpu) +{ + return !is_long_mode(vcpu) && is_pae(vcpu) && is_paging(vcpu); +} + static inline u32 bit(int bitno) { return 1 << (bitno & 31);