[PATCH 2/6] MMU: don't bail on PAT bits in PTE

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A 64bit PTE can have bit7 set to 1 which means "Use this bit for the PAT".
Currently KVM's MMU code treats this bit as reserved, even though it's not.

As long as we're not required to make use of the PAT bits which is only
required for DMA/MMIO from my understanding, we can safely ignore it.

Hyper-V uses this bit for kernel PTEs.

Signed-off-by: Alexander Graf <agraf@xxxxxxx>
---
 arch/x86/kvm/mmu.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 8fcdae9..cce055a 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2169,7 +2169,7 @@ 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] = ~0ull;
+		context->rsvd_bits_mask[1][0] = 0ull;
 		break;
 	}
 }
-- 
1.6.0.2

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