From 2843099fee32a6020e1caa95c6026f28b5d43bff Mon Sep 17 00:00:00 2001 From: Izik Eidus Date: Fri, 3 Oct 2008 17:40:32 +0300 Subject: [PATCH] KVM: MMU: Fix aliased gfns treated as unaliased Some areas of kvm x86 mmu are using gfn offset inside a slot without unaliasing the gfn first. This patch makes sure that the gfn will be unaliased and add gfn_to_memslot_unaliased() to save the calculating of the gfn unaliasing in case we have it unaliased already. Signed-off-by: Izik Eidus Acked-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/mmu.c | 14 ++++++++++---- virt/kvm/kvm_main.c | 9 +++++---- 3 files changed, 17 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 09e6c56..99e3cc1 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -617,6 +617,8 @@ void kvm_disable_tdp(void); int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3); int complete_pio(struct kvm_vcpu *vcpu); +struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn); + static inline struct kvm_mmu_page *page_header(hpa_t shadow_page) { struct page *page = pfn_to_page(shadow_page >> PAGE_SHIFT); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8687758..8904e8a 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -386,7 +386,9 @@ static void account_shadowed(struct kvm *kvm, gfn_t gfn) { int *write_count; - write_count = slot_largepage_idx(gfn, gfn_to_memslot(kvm, gfn)); + gfn = unalias_gfn(kvm, gfn); + write_count = slot_largepage_idx(gfn, + gfn_to_memslot_unaliased(kvm, gfn)); *write_count += 1; } @@ -394,16 +396,20 @@ static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn) { int *write_count; - write_count = slot_largepage_idx(gfn, gfn_to_memslot(kvm, gfn)); + gfn = unalias_gfn(kvm, gfn); + write_count = slot_largepage_idx(gfn, + gfn_to_memslot_unaliased(kvm, gfn)); *write_count -= 1; WARN_ON(*write_count < 0); } static int has_wrprotected_page(struct kvm *kvm, gfn_t gfn) { - struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); + struct kvm_memory_slot *slot; int *largepage_idx; + gfn = unalias_gfn(kvm, gfn); + slot = gfn_to_memslot_unaliased(kvm, gfn); if (slot) { largepage_idx = slot_largepage_idx(gfn, slot); return *largepage_idx; @@ -2973,8 +2979,8 @@ static void audit_write_protection(struct kvm_vcpu *vcpu) if (sp->role.metaphysical) continue; - slot = gfn_to_memslot(vcpu->kvm, sp->gfn); gfn = unalias_gfn(vcpu->kvm, sp->gfn); + slot = gfn_to_memslot_unaliased(vcpu->kvm, sp->gfn); rmapp = &slot->rmap[gfn - slot->base_gfn]; if (*rmapp) printk(KERN_ERR "%s: (%s) shadow page has writable" diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1838052..a65baa9 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -923,7 +923,7 @@ int kvm_is_error_hva(unsigned long addr) } EXPORT_SYMBOL_GPL(kvm_is_error_hva); -static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn) +struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn) { int i; @@ -936,11 +936,12 @@ static struct kvm_memory_slot *__gfn_to_memslot(struct kvm *kvm, gfn_t gfn) } return NULL; } +EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased); struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn) { gfn = unalias_gfn(kvm, gfn); - return __gfn_to_memslot(kvm, gfn); + return gfn_to_memslot_unaliased(kvm, gfn); } int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn) @@ -964,7 +965,7 @@ unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn) struct kvm_memory_slot *slot; gfn = unalias_gfn(kvm, gfn); - slot = __gfn_to_memslot(kvm, gfn); + slot = gfn_to_memslot_unaliased(kvm, gfn); if (!slot) return bad_hva(); return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE); @@ -1215,7 +1216,7 @@ void mark_page_dirty(struct kvm *kvm, gfn_t gfn) struct kvm_memory_slot *memslot; gfn = unalias_gfn(kvm, gfn); - memslot = __gfn_to_memslot(kvm, gfn); + memslot = gfn_to_memslot_unaliased(kvm, gfn); if (memslot && memslot->dirty_bitmap) { unsigned long rel_gfn = gfn - memslot->base_gfn; -- 1.8.2.3