From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [PATCH] KVM: x86: Fix page-tables reserved bits
Date: Wed, 16 Apr 2014 19:04:09 -0300
Message-ID: <20140416220409.GB15155@amt.cnet>
References: <1396582264-9864-1-git-send-email-namit@cs.technion.ac.il>
 <20140416190329.GB8773@amt.cnet>
 <534EF354.3090204@zytor.com>
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Cc: Nadav Amit <namit@cs.technion.ac.il>, gleb@kernel.org,
	pbonzini@redhat.com, tglx@linutronix.de, mingo@redhat.com,
	x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org
To: "H. Peter Anvin" <hpa@zytor.com>
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On Wed, Apr 16, 2014 at 02:17:08PM -0700, H. Peter Anvin wrote:
> On 04/16/2014 12:03 PM, Marcelo Tosatti wrote:
> >> @@ -3550,9 +3550,9 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu,
> >>  		break;
> >>  	case PT64_ROOT_LEVEL:
> >>  		context->rsvd_bits_mask[0][3] = exb_bit_rsvd |
> >> -			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8);
> >> +			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 7);
> >>  		context->rsvd_bits_mask[0][2] = exb_bit_rsvd |
> >> -			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8);
> >> +			rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 7);
> > 
> > Bit 7 is not reserved either, for the PDPTE (its PageSize bit).
> > 
> 
> In long mode (IA-32e), bit 7 is definitely reserved.
> 
> 	-hpa

There is a separate reserved mask for PS=1, nevermind.