From 6081460291017b1f01a282e85ec1c80ffb695e8a Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti <mtosatti@redhat.com> Date: Mon, 15 Jun 2009 17:01:53 -0300 Subject: [PATCH 2/3] KVM: MMU: protect kvm_mmu_change_mmu_pages with mmu_lock KVM: MMU: protect kvm_mmu_change_mmu_pages with mmu_lock kvm_handle_hva, called by MMU notifiers, manipulates mmu data only with the protection of mmu_lock. Update kvm_mmu_change_mmu_pages callers to take mmu_lock, thus protecting against kvm_handle_hva. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com> Message-ID: <20090615200153.GA22097@amt.cnet> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Acked-by: john cooper <john.cooper@redhat.com> Acked-by: Avi Kivity <avi@redhat.com> Acked-by: Andrea Arcangeli <aarcange@redhat.com> Bugzilla: 504237 --- arch/x86/kvm/mmu.c | 2 -- arch/x86/kvm/x86.c | 6 ++++++ 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 247dca3..c36a9d4 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2808,7 +2808,6 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) { struct kvm_mmu_page *sp; - spin_lock(&kvm->mmu_lock); list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) { int i; u64 *pt; @@ -2823,7 +2822,6 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) pt[i] &= ~PT_WRITABLE_MASK; } kvm_flush_remote_tlbs(kvm); - spin_unlock(&kvm->mmu_lock); } void kvm_mmu_zap_all(struct kvm *kvm) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e91482a..0cbdf14 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1570,10 +1570,12 @@ static int kvm_vm_ioctl_set_nr_mmu_pages(struct kvm *kvm, return -EINVAL; down_write(&kvm->slots_lock); + spin_lock(&kvm->mmu_lock); kvm_mmu_change_mmu_pages(kvm, kvm_nr_mmu_pages); kvm->arch.n_requested_mmu_pages = kvm_nr_mmu_pages; + spin_unlock(&kvm->mmu_lock); up_write(&kvm->slots_lock); return 0; } @@ -1749,7 +1751,9 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, /* If nothing is dirty, don't bother messing with page tables. */ if (is_dirty) { + spin_lock(&kvm->mmu_lock); kvm_mmu_slot_remove_write_access(kvm, log->slot); + spin_unlock(&kvm->mmu_lock); kvm_flush_remote_tlbs(kvm); memslot = &kvm->memslots[log->slot]; n = ALIGN(memslot->npages, BITS_PER_LONG) / 8; @@ -4343,12 +4347,14 @@ int kvm_arch_set_memory_region(struct kvm *kvm, } } + spin_lock(&kvm->mmu_lock); if (!kvm->arch.n_requested_mmu_pages) { unsigned int nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm); kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages); } kvm_mmu_slot_remove_write_access(kvm, mem->slot); + spin_unlock(&kvm->mmu_lock); kvm_flush_remote_tlbs(kvm); return 0; -- 1.6.3.rc4.29.g8146