diff options
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 17 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/paging_tmpl.h | 3 |
2 files changed, 19 insertions, 1 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 2360d33a27b1..7ec3d057e8e0 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -2985,6 +2985,7 @@ static bool kvm_is_mmio_pfn(kvm_pfn_t pfn) /* Bits which may be returned by set_spte() */ #define SET_SPTE_WRITE_PROTECTED_PT BIT(0) #define SET_SPTE_NEED_REMOTE_TLB_FLUSH BIT(1) +#define SET_SPTE_SPURIOUS BIT(2) static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned int pte_access, int level, @@ -3073,7 +3074,9 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, spte = mark_spte_for_access_track(spte); set_pte: - if (mmu_spte_update(sptep, spte)) + if (*sptep == spte) + ret |= SET_SPTE_SPURIOUS; + else if (mmu_spte_update(sptep, spte)) ret |= SET_SPTE_NEED_REMOTE_TLB_FLUSH; return ret; } @@ -3128,6 +3131,15 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, if (unlikely(is_mmio_spte(*sptep))) ret = RET_PF_EMULATE; + /* + * The fault is fully spurious if and only if the new SPTE and old SPTE + * are identical, and emulation is not required. + */ + if ((set_spte_ret & SET_SPTE_SPURIOUS) && ret == RET_PF_FIXED) { + WARN_ON_ONCE(!was_rmapped); + return RET_PF_SPURIOUS; + } + pgprintk("%s: setting spte %llx\n", __func__, *sptep); trace_kvm_mmu_set_spte(level, gfn, sptep); if (!was_rmapped && is_large_pte(*sptep)) @@ -3364,6 +3376,9 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, int write, ret = mmu_set_spte(vcpu, it.sptep, ACC_ALL, write, level, base_gfn, pfn, prefault, map_writable); + if (ret == RET_PF_SPURIOUS) + return ret; + direct_pte_prefetch(vcpu, it.sptep); ++vcpu->stat.pf_fixed; return ret; diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index e1066226b8f0..188ec2633bc5 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -711,6 +711,9 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gpa_t addr, ret = mmu_set_spte(vcpu, it.sptep, gw->pte_access, write_fault, it.level, base_gfn, pfn, prefault, map_writable); + if (ret == RET_PF_SPURIOUS) + return ret; + FNAME(pte_prefetch)(vcpu, gw, it.sptep); ++vcpu->stat.pf_fixed; return ret; |