Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

[linux-2.6-microblaze.git] / arch / x86 / kvm / mmu.h

diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index bf8dbc4..e6cae6f 100644 (file)
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -214,27 +214,27 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
  */
 static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
                                  unsigned pte_access, unsigned pte_pkey,
-                                 unsigned pfec)
+                                 u64 access)
 {
-       int cpl = static_call(kvm_x86_get_cpl)(vcpu);
+       /* strip nested paging fault error codes */
+       unsigned int pfec = access;
        unsigned long rflags = static_call(kvm_x86_get_rflags)(vcpu);
 
        /*
-        * If CPL < 3, SMAP prevention are disabled if EFLAGS.AC = 1.
+        * For explicit supervisor accesses, SMAP is disabled if EFLAGS.AC = 1.
+        * For implicit supervisor accesses, SMAP cannot be overridden.
         *
-        * If CPL = 3, SMAP applies to all supervisor-mode data accesses
-        * (these are implicit supervisor accesses) regardless of the value
-        * of EFLAGS.AC.
+        * SMAP works on supervisor accesses only, and not_smap can
+        * be set or not set when user access with neither has any bearing
+        * on the result.
         *
-        * This computes (cpl < 3) && (rflags & X86_EFLAGS_AC), leaving
-        * the result in X86_EFLAGS_AC. We then insert it in place of
-        * the PFERR_RSVD_MASK bit; this bit will always be zero in pfec,
-        * but it will be one in index if SMAP checks are being overridden.
-        * It is important to keep this branchless.
+        * We put the SMAP checking bit in place of the PFERR_RSVD_MASK bit;
+        * this bit will always be zero in pfec, but it will be one in index
+        * if SMAP checks are being disabled.
         */
-       unsigned long smap = (cpl - 3) & (rflags & X86_EFLAGS_AC);
-       int index = (pfec >> 1) +
-                   (smap >> (X86_EFLAGS_AC_BIT - PFERR_RSVD_BIT + 1));
+       u64 implicit_access = access & PFERR_IMPLICIT_ACCESS;
+       bool not_smap = ((rflags & X86_EFLAGS_AC) | implicit_access) == X86_EFLAGS_AC;
+       int index = (pfec + (not_smap << PFERR_RSVD_BIT)) >> 1;
        bool fault = (mmu->permissions[index] >> pte_access) & 1;
        u32 errcode = PFERR_PRESENT_MASK;
 
@@ -317,12 +317,12 @@ static inline void kvm_update_page_stats(struct kvm *kvm, int level, int count)
        atomic64_add(count, &kvm->stat.pages[level - 1]);
 }
 
-gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
+gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
                           struct x86_exception *exception);
 
 static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu,
                                      struct kvm_mmu *mmu,
-                                     gpa_t gpa, u32 access,
+                                     gpa_t gpa, u64 access,
                                      struct x86_exception *exception)
 {
        if (mmu != &vcpu->arch.nested_mmu)