KVM: Fix vcpu freeing for guest smp

A vcpu can pin up to four mmu shadow pages, which means the freeing
loop will never terminate.  Fix by first unpinning shadow pages on
all vcpus, then freeing shadow pages.

Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Avi Kivity 2007-06-05 12:17:03 +03:00
parent 313899477f
commit 7b53aa5650
2 changed files with 17 additions and 2 deletions

View File

@ -381,6 +381,16 @@ static void free_pio_guest_pages(struct kvm_vcpu *vcpu)
}
}
static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu)
{
if (!vcpu->vmcs)
return;
vcpu_load(vcpu);
kvm_mmu_unload(vcpu);
vcpu_put(vcpu);
}
static void kvm_free_vcpu(struct kvm_vcpu *vcpu)
{
if (!vcpu->vmcs)
@ -401,6 +411,11 @@ static void kvm_free_vcpus(struct kvm *kvm)
{
unsigned int i;
/*
* Unpin any mmu pages first.
*/
for (i = 0; i < KVM_MAX_VCPUS; ++i)
kvm_unload_vcpu_mmu(&kvm->vcpus[i]);
for (i = 0; i < KVM_MAX_VCPUS; ++i)
kvm_free_vcpu(&kvm->vcpus[i]);
}

View File

@ -838,11 +838,12 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
int i;
struct kvm_mmu_page *page;
if (!VALID_PAGE(vcpu->mmu.root_hpa))
return;
#ifdef CONFIG_X86_64
if (vcpu->mmu.shadow_root_level == PT64_ROOT_LEVEL) {
hpa_t root = vcpu->mmu.root_hpa;
ASSERT(VALID_PAGE(root));
page = page_header(root);
--page->root_count;
vcpu->mmu.root_hpa = INVALID_PAGE;
@ -853,7 +854,6 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
hpa_t root = vcpu->mmu.pae_root[i];
if (root) {
ASSERT(VALID_PAGE(root));
root &= PT64_BASE_ADDR_MASK;
page = page_header(root);
--page->root_count;