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: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Message-Id: <20210920235134.101970-3-krish.sadhukhan@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Krish Sadhukhan 2021-09-20 19:51:31 -04:00 committed by Paolo Bonzini
parent 78b497f2e6
commit 174a921b69

View file

@ -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;
}