diff options
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 92ff15969a36..53be6c2a5b0c 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4653,10 +4653,16 @@ static int kvm_mmu_faultin_pfn(struct kvm_vcpu *vcpu, /* * Retry the page fault if the gfn hit a memslot that is being deleted * or moved. This ensures any existing SPTEs for the old memslot will - * be zapped before KVM inserts a new MMIO SPTE for the gfn. + * be zapped before KVM inserts a new MMIO SPTE for the gfn. Punt the + * error to userspace if this is a prefault, as KVM's prefaulting ABI + * doesn't provide the same forward progress guarantees as KVM_RUN. */ - if (slot->flags & KVM_MEMSLOT_INVALID) + if (slot->flags & KVM_MEMSLOT_INVALID) { + if (fault->prefetch) + return -EAGAIN; + return RET_PF_RETRY; + } if (slot->id == APIC_ACCESS_PAGE_PRIVATE_MEMSLOT) { /* |