From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Dong, Eddie" <eddie.dong@intel.com>
Subject: RE: [PATCH 06/16] vmx: nest: handling VMX instruction
	exits
Date: Mon, 13 Sep 2010 22:29:37 +0800
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To: Tim Deegan <Tim.Deegan@citrix.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, "Dong,
	Eddie" <eddie.dong@intel.com>, "He, Qing" <qing.he@intel.com>
List-Id: xen-devel@lists.xenproject.org

Tim Deegan wrote:
> At 08:05 +0100 on 10 Sep (1284105901), Dong, Eddie wrote:
>> Qing He wrote:
>>> +static int __clear_current_vvmcs(struct vmx_nest_struct *nest) +{
>>> +    int rc;
>>> +
>>> +    if ( nest->svmcs )
>>> +        __vmpclear(virt_to_maddr(nest->svmcs));
>>> +
>>> +#if !CONFIG_VVMCS_MAPPING
>>> +    rc =3D hvm_copy_to_guest_phys(nest->gvmcs_pa, nest->vvmcs,
>>=20
>>=20
>> Qing:
>> 	Why this may be failure? The only reason may be nest->gvmcs_pa, but
>> I guess we already verified the address.=20
>>=20
>=20
> It was verified at load time, but the guest could have ballooned it
> out in the meantime.

If the L1 guest allocated that GPA as VMCS memory, it can't balloon them ou=
t.
If L1 is a mallicious guest and ballooned the VMCS memory out, it is worthy=
 to do. Not?

>=20
> Cheers,
>=20

Thx, Eddie=