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KVM: SVM: Fix CPL updates
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Keep CPL at 0 in real mode and at 3 in VM86. In protected/long mode, use
RPL rather than DPL of the code segment.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
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Kevin Wolf authored and Avi Kivity committed Mar 8, 2012
1 parent 66b0ab8 commit ea5e97e
Showing 1 changed file with 16 additions and 3 deletions.
19 changes: 16 additions & 3 deletions arch/x86/kvm/svm.c
Original file line number Diff line number Diff line change
Expand Up @@ -1332,6 +1332,21 @@ static void svm_vcpu_put(struct kvm_vcpu *vcpu)
wrmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]);
}

static void svm_update_cpl(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
int cpl;

if (!is_protmode(vcpu))
cpl = 0;
else if (svm->vmcb->save.rflags & X86_EFLAGS_VM)
cpl = 3;
else
cpl = svm->vmcb->save.cs.selector & 0x3;

svm->vmcb->save.cpl = cpl;
}

static unsigned long svm_get_rflags(struct kvm_vcpu *vcpu)
{
return to_svm(vcpu)->vmcb->save.rflags;
Expand Down Expand Up @@ -1607,9 +1622,7 @@ static void svm_set_segment(struct kvm_vcpu *vcpu,
s->attrib |= (var->g & 1) << SVM_SELECTOR_G_SHIFT;
}
if (seg == VCPU_SREG_CS)
svm->vmcb->save.cpl
= (svm->vmcb->save.cs.attrib
>> SVM_SELECTOR_DPL_SHIFT) & 3;
svm_update_cpl(vcpu);

mark_dirty(svm->vmcb, VMCB_SEG);
}
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