Commit 174a921b authored by Krish Sadhukhan's avatar Krish Sadhukhan Committed by Paolo Bonzini
Browse files

nSVM: Check for reserved encodings of TLB_CONTROL in nested VMCB 



According to section "TLB Flush" in APM vol 2,

    "Support for TLB_CONTROL commands other than the first two, is
     optional and is indicated by CPUID Fn8000_000A_EDX[FlushByAsid].

     All encodings of TLB_CONTROL not defined in the APM are reserved."

Signed-off-by: default avatarKrish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <20210920235134.101970-3-krish.sadhukhan@oracle.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 78b497f2

arch/x86/kvm/svm/nested.c

+15 −0
Original line number Diff line number Diff line
@@ -238,6 +238,18 @@ static bool nested_svm_check_bitmap_pa(struct kvm_vcpu *vcpu, u64 pa, u32 size) 
	    kvm_vcpu_is_legal_gpa(vcpu, addr + size - 1);

}



static bool nested_svm_check_tlb_ctl(struct kvm_vcpu *vcpu, u8 tlb_ctl)

{

	/* Nested FLUSHBYASID is not supported yet.  */

	switch(tlb_ctl) {

		case TLB_CONTROL_DO_NOTHING:

		case TLB_CONTROL_FLUSH_ALL_ASID:

			return true;

		default:

			return false;

	}

}



static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu,

				       struct vmcb_control_area *control)

{
@@ -257,6 +269,9 @@ static bool nested_vmcb_check_controls(struct kvm_vcpu *vcpu, 
					   IOPM_SIZE)))

		return false;



	if (CC(!nested_svm_check_tlb_ctl(vcpu, control->tlb_ctl)))

		return false;



	return true;

}