[PATCH v2] KVM MMU: check reserved bits only when CR4.PSE=1 or CR4.PAE=1
From: Xiao Guangrong
Date: Tue Mar 16 2010 - 23:45:16 EST
- The RSV bit is possibility set in error code when #PF occurred
only if CR4.PSE=1 or CR4.PAE=1
- context->rsvd_bits_mask[1][0] is always 0
Changlog:
Move this operation to reset_rsvds_bits_mask() address Avi Kivity's suggestion
Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 12 +++++++++---
1 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index b137515..c49f8ec 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2288,18 +2288,26 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
if (!is_nx(vcpu))
exb_bit_rsvd = rsvd_bits(63, 63);
+
+ context->rsvd_bits_mask[1][0] = 0;
switch (level) {
case PT32_ROOT_LEVEL:
/* no rsvd bits for 2 level 4K page table entries */
context->rsvd_bits_mask[0][1] = 0;
context->rsvd_bits_mask[0][0] = 0;
+
+ /* check rsvd bits only when CR4.PSE=1 or CR4.PAE=1 */
+ if (!is_pse(vcpu)) {
+ context->rsvd_bits_mask[1][1] = 0;
+ break;
+ }
+
if (is_cpuid_PSE36())
/* 36bits PSE 4MB page */
context->rsvd_bits_mask[1][1] = rsvd_bits(17, 21);
else
/* 32 bits PSE 4MB page */
context->rsvd_bits_mask[1][1] = rsvd_bits(13, 21);
- context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
break;
case PT32E_ROOT_LEVEL:
context->rsvd_bits_mask[0][2] =
@@ -2312,7 +2320,6 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
context->rsvd_bits_mask[1][1] = exb_bit_rsvd |
rsvd_bits(maxphyaddr, 62) |
rsvd_bits(13, 20); /* large page */
- context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
break;
case PT64_ROOT_LEVEL:
context->rsvd_bits_mask[0][3] = exb_bit_rsvd |
@@ -2330,7 +2337,6 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
context->rsvd_bits_mask[1][1] = exb_bit_rsvd |
rsvd_bits(maxphyaddr, 51) |
rsvd_bits(13, 20); /* large page */
- context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
break;
}
}
--
1.6.1.2
--
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