KVM: VMX: give unrestricted guest full control of CR3

Now CR3 is not forced to a host-controlled value when paging is
disabled in an unrestricted guest, CR3 load/store exiting can be
left disabled (for an unrestricted guest).  And because CR0.WP
and CR4.PAE/PSE are also not force to host-controlled values,
all of ept_update_paging_mode_cr0() is no longer needed, i.e.
skip ept_update_paging_mode_cr0() for an unrestricted guest.

Because MOV CR3 no longer exits when paging is disabled for an
unrestricted guest, vmx_decache_cr3() must always read GUEST_CR3
from the VMCS for an unrestricted guest.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
This commit is contained in:
Sean Christopherson 2018-03-05 12:04:40 -08:00 committed by Paolo Bonzini
parent 5dc1f044a3
commit b4d185175b
1 changed files with 2 additions and 2 deletions

View File

@ -4314,7 +4314,7 @@ static void vmx_decache_cr0_guest_bits(struct kvm_vcpu *vcpu)
static void vmx_decache_cr3(struct kvm_vcpu *vcpu)
{
if (enable_ept && is_paging(vcpu))
if (enable_unrestricted_guest || (enable_ept && is_paging(vcpu)))
vcpu->arch.cr3 = vmcs_readl(GUEST_CR3);
__set_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail);
}
@ -4451,7 +4451,7 @@ static void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
}
#endif
if (enable_ept)
if (enable_ept && !enable_unrestricted_guest)
ept_update_paging_mode_cr0(&hw_cr0, cr0, vcpu);
vmcs_writel(CR0_READ_SHADOW, cr0);