KVM: x86: do not load vmcs12 pages while still in SMM

If the vCPU enters system management mode while running a nested guest,
RSM starts processing the vmentry while still in SMM.  In that case,
however, the pages pointed to by the vmcs12 might be incorrectly
loaded from SMRAM.  To avoid this, delay the handling of the pages
until just before the next vmentry.  This is done with a new request
and a new entry in kvm_x86_ops, which we will be able to reuse for
nested VMX state migration.

Extracted from a patch by Jim Mattson and KarimAllah Ahmed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini
2018-07-18 18:49:01 +02:00
parent fa3899add1
commit 7f7f1ba33c
3 changed files with 41 additions and 18 deletions

View File

@@ -7260,6 +7260,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
bool req_immediate_exit = false;
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_GET_VMCS12_PAGES, vcpu))
kvm_x86_ops->get_vmcs12_pages(vcpu);
if (kvm_check_request(KVM_REQ_MMU_RELOAD, vcpu))
kvm_mmu_unload(vcpu);
if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu))