Commit 37687c40 authored by Maxim Levitsky's avatar Maxim Levitsky Committed by Paolo Bonzini
Browse files

KVM: x86: reset pdptrs_from_userspace when exiting smm 



When exiting SMM, pdpts are loaded again from the guest memory.

This fixes a theoretical bug, when exit from SMM triggers entry to the
nested guest which re-uses some of the migration
code which uses this flag as a workaround for a legacy userspace.

Signed-off-by: default avatarMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210913140954.165665-4-mlevitsk@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent e2e6e449

arch/x86/kvm/x86.c

+7 −0
Original line number Diff line number Diff line
@@ -7658,6 +7658,13 @@ static void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm) 


		/* Process a latched INIT or SMI, if any.  */

		kvm_make_request(KVM_REQ_EVENT, vcpu);



		/*

		 * Even if KVM_SET_SREGS2 loaded PDPTRs out of band,

		 * on SMM exit we still need to reload them from

		 * guest memory

		 */

		vcpu->arch.pdptrs_from_userspace = false;

	}



	kvm_mmu_reset_context(vcpu);