From 22d95b1282810f5af599ee292b3fc443aefbdad0 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Fri, 14 Sep 2007 20:26:06 +0300 Subject: KVM: MMU: Fix rare oops on guest context switch A guest context switch to an uncached cr3 can require allocation of shadow pages, but we only recycle shadow pages in kvm_mmu_page_fault(). Move shadow page recycling to mmu_topup_memory_caches(), which is called from both the page fault handler and from guest cr3 reload. Signed-off-by: Avi Kivity Signed-off-by: Linus Torvalds --- drivers/kvm/mmu.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/kvm/mmu.c') diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index 1a87ba9..23965aa 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -273,12 +273,14 @@ static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu) int r; r = __mmu_topup_memory_caches(vcpu, GFP_NOWAIT); + kvm_mmu_free_some_pages(vcpu); if (r < 0) { spin_unlock(&vcpu->kvm->lock); kvm_arch_ops->vcpu_put(vcpu); r = __mmu_topup_memory_caches(vcpu, GFP_KERNEL); kvm_arch_ops->vcpu_load(vcpu); spin_lock(&vcpu->kvm->lock); + kvm_mmu_free_some_pages(vcpu); } return r; } @@ -1208,7 +1210,7 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) return kvm_mmu_unprotect_page(vcpu, gpa >> PAGE_SHIFT); } -void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) +void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) { while (vcpu->kvm->n_free_mmu_pages < KVM_REFILL_PAGES) { struct kvm_mmu_page *page; @@ -1218,7 +1220,6 @@ void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) kvm_mmu_zap_page(vcpu->kvm, page); } } -EXPORT_SYMBOL_GPL(kvm_mmu_free_some_pages); static void free_mmu_pages(struct kvm_vcpu *vcpu) { -- cgit v1.1