diff options
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rm_mmu.c | 44 |
1 files changed, 17 insertions, 27 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c index 084ad54c73cd..411720f59643 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c +++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c @@ -667,40 +667,30 @@ long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags, rev->guest_rpte = r; note_hpte_modification(kvm, rev); } - r = (be64_to_cpu(hpte[1]) & ~mask) | bits; /* Update HPTE */ if (v & HPTE_V_VALID) { - rb = compute_tlbie_rb(v, r, pte_index); - hpte[0] = cpu_to_be64(v & ~HPTE_V_VALID); - do_tlbies(kvm, &rb, 1, global_invalidates(kvm, flags), true); /* - * If the host has this page as readonly but the guest - * wants to make it read/write, reduce the permissions. - * Checking the host permissions involves finding the - * memslot and then the Linux PTE for the page. + * If the page is valid, don't let it transition from + * readonly to writable. If it should be writable, we'll + * take a trap and let the page fault code sort it out. */ - if (hpte_is_writable(r) && kvm->arch.using_mmu_notifiers) { - unsigned long psize, gfn, hva; - struct kvm_memory_slot *memslot; - pgd_t *pgdir = vcpu->arch.pgdir; - pte_t pte; - - psize = hpte_page_size(v, r); - gfn = ((r & HPTE_R_RPN) & ~(psize - 1)) >> PAGE_SHIFT; - memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn); - if (memslot) { - hva = __gfn_to_hva_memslot(memslot, gfn); - pte = lookup_linux_pte_and_update(pgdir, hva, - 1, &psize); - if (pte_present(pte) && !pte_write(pte)) - r = hpte_make_readonly(r); - } + pte = be64_to_cpu(hpte[1]); + r = (pte & ~mask) | bits; + if (hpte_is_writable(r) && kvm->arch.using_mmu_notifiers && + !hpte_is_writable(pte)) + r = hpte_make_readonly(r); + /* If the PTE is changing, invalidate it first */ + if (r != pte) { + rb = compute_tlbie_rb(v, r, pte_index); + hpte[0] = cpu_to_be64((v & ~HPTE_V_VALID) | + HPTE_V_ABSENT); + do_tlbies(kvm, &rb, 1, global_invalidates(kvm, flags), + true); + hpte[1] = cpu_to_be64(r); } } - hpte[1] = cpu_to_be64(r); - eieio(); - hpte[0] = cpu_to_be64(v & ~HPTE_V_HVLOCK); + unlock_hpte(hpte, v & ~HPTE_V_HVLOCK); asm volatile("ptesync" : : : "memory"); return H_SUCCESS; } |