From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@suse.com>
Subject: Re: [PATCH 1/2] VMX: fix VMCS race on context-switch
	paths
Date: Wed, 15 Feb 2017 04:00:18 -0700
Message-ID: <58A442D2020000780013A17B@prv-mh.provo.novell.com>
References: <58A2E8B70200007800139946@prv-mh.provo.novell.com>
 <58A2E9F9020000780013995D@prv-mh.provo.novell.com>
 <1487154433.3588.1.camel@citrix.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
Return-path: <xen-devel-bounces@lists.xen.org>
Received: from mail6.bemta6.messagelabs.com ([193.109.254.103])
 by lists.xenproject.org with esmtp (Exim 4.84_2)
 (envelope-from <JBeulich@suse.com>) id 1cdxJv-0007wC-Hb
 for xen-devel@lists.xenproject.org; Wed, 15 Feb 2017 11:00:23 +0000
In-Reply-To: <1487154433.3588.1.camel@citrix.com>
Content-Disposition: inline
List-Unsubscribe: <https://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
 <mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <https://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
 <mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Errors-To: xen-devel-bounces@lists.xen.org
Sender: "Xen-devel" <xen-devel-bounces@lists.xen.org>
To: Sergey Dyasli <sergey.dyasli@citrix.com>
Cc: Kevin Tian <kevin.tian@intel.com>, "Kevin.Mayer@gdata.de" <Kevin.Mayer@gdata.de>, Andrew Cooper <Andrew.Cooper3@citrix.com>, Anshul Makkar <anshul.makkar@citrix.com>, "jun.nakajima@intel.com" <jun.nakajima@intel.com>, "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>
List-Id: xen-devel@lists.xenproject.org

Pj4+IE9uIDE1LjAyLjE3IGF0IDExOjI3LCA8c2VyZ2V5LmR5YXNsaUBjaXRyaXguY29tPiB3cm90
ZToKPiBUaGlzIGlzIHdoYXQgSSdtIGdldHRpbmcgZHVyaW5nIHRoZSBvcmlnaW5hbCB0ZXN0IGNh
c2UgKDMyIFZNcyByZWJvb3QpOgo+IAo+IChYRU4pIFsgMTQwNy43ODkzMjldIFdhdGNoZG9nIHRp
bWVyIGRldGVjdHMgdGhhdCBDUFUxMiBpcyBzdHVjayEKPiAoWEVOKSBbIDE0MDcuNzk1NzI2XSAt
LS0tWyBYZW4tNC42LjEteHMtbG9jYWwgIHg4Nl82NCAgZGVidWc9biAgTm90IHRhaW50ZWQgXS0t
LS0KPiAoWEVOKSBbIDE0MDcuODAzNzc0XSBDUFU6ICAgIDEyCj4gKFhFTikgWyAxNDA3LjgwNjk3
NV0gUklQOiAgICBlMDA4Ols8ZmZmZjgyZDA4MDFlYTJhMj5dIAo+IHZteF92bWNzX3JlbG9hZCsw
eDMyLzB4NTAKPiAoWEVOKSBbIDE0MDcuODE0OTI2XSBSRkxBR1M6IDAwMDAwMDAwMDAwMDAwMTMg
ICBDT05URVhUOiBoeXBlcnZpc29yIChkMjMwdjApCj4gKFhFTikgWyAxNDA3LjgyMjQ4Nl0gcmF4
OiAwMDAwMDAwMDAwMDAwMDAwICAgcmJ4OiBmZmZmODMwMDc5ZWU3MDAwICAgcmN4OiAwMDAwMDAw
MDAwMDAwMDAwCj4gKFhFTikgWyAxNDA3LjgzMTQwN10gcmR4OiAwMDAwMDA2ZjhmNzJjZTAwICAg
cnNpOiBmZmZmODMyOWIzZWZiZmU4ICAgcmRpOiBmZmZmODMwMDc5ZWU3MDAwCj4gKFhFTikgWyAx
NDA3Ljg0MDMyNl0gcmJwOiBmZmZmODMwMDdiYWI3MDAwICAgcnNwOiBmZmZmODM0MDBmYWI3ZGM4
ICAgcjg6IDAwMDAwMTQ2OGU5ZTNjY2MKPiAoWEVOKSBbIDE0MDcuODQ5MjQ2XSByOTogIGZmZmY4
MzQwM2ZmZTcwMDAgICByMTA6IDAwMDAwMTQ2YzkxYzE3MzcgICByMTE6IGZmZmY4MzNhOTU1OGMz
MTAKPiAoWEVOKSBbIDE0MDcuODU4MTY2XSByMTI6IGZmZmY4MzNhOTU1OGMwMDAgICByMTM6IDAw
MDAwMDAwMDAwMDAwMGMgICByMTQ6IGZmZmY4MzQwM2ZmZTcwMDAKPiAoWEVOKSBbIDE0MDcuODY3
MDg1XSByMTU6IGZmZmY4MmQwODAzNjQ2NDAgICBjcjA6IDAwMDAwMDAwODAwNTAwMzMgICBjcjQ6
IDAwMDAwMDAwMDAzNTI2ZTAKPiAoWEVOKSBbIDE0MDcuODc2MDA1XSBjcjM6IDAwMDAwMDI5NGIw
NzQwMDAgICBjcjI6IDAwMDAwN2ZlZmQ3Y2UxNTAKPiAoWEVOKSBbIDE0MDcuODgyNTk5XSBkczog
MDAwMCAgIGVzOiAwMDAwICAgZnM6IDAwMDAgICBnczogMDAwMCAgIHNzOiAwMDAwICAgY3M6IGUw
MDgKPiAoWEVOKSBbIDE0MDcuODkwOTM4XSBYZW4gY29kZSBhcm91bmQgPGZmZmY4MmQwODAxZWEy
YTI+ICh2bXhfdm1jc19yZWxvYWQrMHgzMi8weDUwKToKPiAoWEVOKSBbIDE0MDcuODk5Mjc3XSAg
ODQgMDAgMDAgMDAgMDAgMDAgZjMgOTAgPDgzPiBiZiBlOCAwNSAwMCAwMCBmZiA3NSBmNSBlOSBh
MCBmYSBmZiBmZiBmMyBjMwo+IChYRU4pIFsgMTQwNy45MDg2NzldIFhlbiBzdGFjayB0cmFjZSBm
cm9tIHJzcD1mZmZmODM0MDBmYWI3ZGM4Ogo+IChYRU4pIFsgMTQwNy45MTQ5ODJdICAgIGZmZmY4
MmQwODAxNmM1OGQgMDAwMDAwMDAwMDAwMTAwMCAwMDAwMDAwMDAwMDAwMDAwIDAwMDAwMDAwMDAw
MDAwMDAKPiAoWEVOKSBbIDE0MDcuOTIzOTk4XSAgICAwMDAwMDAwMDAwMDAwMjA2IDAwMDAwMDAw
MDAwMDAwODYgMDAwMDAwMDAwMDAwMDI4NiAwMDAwMDAwMDAwMDAwMDBjCj4gKFhFTikgWyAxNDA3
LjkzMzAxN10gICAgZmZmZjgzMDA3YmFiNzA1OCBmZmZmODJkMDgwMzY0NjQwIGZmZmY4MzAwN2Jh
YjcwMDAgMDAwMDAxNDZhN2YyNjQ5NQo+IChYRU4pIFsgMTQwNy45NDIwMzJdICAgIGZmZmY4MzAw
NzllZTcwMDAgZmZmZjgzM2E5NTU4Y2Y4NCBmZmZmODMzYTk1NThjMDAwIGZmZmY4MmQwODAzNjQ2
NDAKPiAoWEVOKSBbIDE0MDcuOTUxMDQ4XSAgICBmZmZmODJkMDgwMTJmYjhlIGZmZmY4MzQwMGZh
YmRhOTggZmZmZjgzNDAwZmFiYTE0OCBmZmZmODM0MDNmZmU3MDAwCj4gKFhFTikgWyAxNDA3Ljk2
MDA2N10gICAgZmZmZjgzNDAwZmFiYTE2MCBmZmZmODM0MDBmYWJkYTQwIGZmZmY4MmQwODAxNjQz
MDUgMDAwMDAwMDAwMDAwMDAwYwo+IChYRU4pIFsgMTQwNy45NjkwODNdICAgIGZmZmY4MzAwNzll
ZTcwMDAgMDAwMDAwMDAwMWM5YzM4MCBmZmZmODJkMDgwMTM2NDAwIDAwMDAwMDQ0MDAwMDAxMWQK
PiAoWEVOKSBbIDE0MDcuOTc4MTAxXSAgICAwMDAwMDAwMGZmZmZmZmZmIGZmZmZmZmZmZmZmZmZm
ZmYgZmZmZjgzNDAwZmFiMDAwMCBmZmZmODJkMDgwMzQ4ZDAwCj4gKFhFTikgWyAxNDA3Ljk4NzEx
Nl0gICAgZmZmZjgzM2E5NTU4YzAwMCBmZmZmODJkMDgwMzY0NjQwIGZmZmY4MmQwODAxMzMxMWMg
ZmZmZjgzMDA3OWVlNzAwMAo+IChYRU4pIFsgMTQwNy45OTYxMzRdICAgIGZmZmY4MzQwMGZhYjAw
MDAgZmZmZjgzMDA3OWVlNzAwMCBmZmZmODM0MDNmZmU3MDAwIDAwMDAwMDAwZmZmZmZmZmYKPiAo
WEVOKSBbIDE0MDguMDA1MTUxXSAgICBmZmZmODJkMDgwMTY3ZDM1IGZmZmY4MzAwN2JhYjcwMDAg
MDAwMDAwMDAwMDAwMDAwMSBmZmZmZmE4MDA3N2Y5NzAwCj4gKFhFTikgWyAxNDA4LjAxNDE2N10g
ICAgZmZmZmZhODAwNzViZjkwMCBmZmZmZmE4MDA3N2Y5ODIwIDAwMDAwMDAwMDAwMDAwMDAgMDAw
MDAwMDAwMDAwMDAwMAo+IChYRU4pIFsgMTQwOC4wMjMxODRdICAgIGZmZmZmYTgwMDg4ODljMDAg
MDAwMDAwMDAwMmZhMWU3OCAwMDAwMDAzYjZlZDE4ZDc4IDAwMDAwMDAwMDAwMDAwMDAKPiAoWEVO
KSBbIDE0MDguMDMyMjAyXSAgICAwMDAwMDAwMDA2OGU3NzgwIGZmZmZmYTgwMDc1YmE3OTAgZmZm
ZmZhODAwNzdmOTg0OCBmZmZmZjgwMDAyN2Y5ZTgwCj4gKFhFTikgWyAxNDA4LjA0MTIyMF0gICAg
MDAwMDAwMDAwMDAwMDAwMSAwMDAwMDBmYzAwMDAwMDAwIGZmZmZmODgwMDQyNDk5YzIgMDAwMDAw
MDAwMDAwMDAwMAo+IChYRU4pIFsgMTQwOC4wNTAyMzVdICAgIDAwMDAwMDAwMDAwMDAyNDYgZmZm
ZmY4MDAwMGI5Y2I1OCAwMDAwMDAwMDAwMDAwMDAwIDgwMjQ4ZTAwZTAwOGUxZjAKPiAoWEVOKSBb
IDE0MDguMDU5MjUzXSAgICAwMDAwMDAwMGZmZmY4MmQwIDgwMjQ4ZTAwZTAwOGUyMDAgMDAwMDAw
MDBmZmZmODJkMCA4MDI0OGUwMDAwMDAwMDBjCj4gKFhFTikgWyAxNDA4LjA2ODI2OF0gICAgZmZm
ZjgzMDA3OWVlNzAwMCAwMDAwMDA2ZjhmNzJjZTAwIDAwMDAwMDAwZmZmZjgyZDAKPiAoWEVOKSBb
IDE0MDguMDc1NjM4XSBYZW4gY2FsbCB0cmFjZToKPiAoWEVOKSBbIDE0MDguMDc5MzIyXSAgICBb
PGZmZmY4MmQwODAxZWEyYTI+XSB2bXhfdm1jc19yZWxvYWQrMHgzMi8weDUwCj4gKFhFTikgWyAx
NDA4LjA4NjMwM10gICAgWzxmZmZmODJkMDgwMTZjNThkPl0gY29udGV4dF9zd2l0Y2grMHg4NWQv
MHhlYjAKPiAoWEVOKSBbIDE0MDguMDkzMzgwXSAgICBbPGZmZmY4MmQwODAxMmZiOGU+XSBzY2hl
ZHVsZS5jI3NjaGVkdWxlKzB4NDZlLzB4N2QwCj4gKFhFTikgWyAxNDA4LjEwMDk0Ml0gICAgWzxm
ZmZmODJkMDgwMTY0MzA1Pl0gcmVwcm9ncmFtX3RpbWVyKzB4NzUvMHhlMAo+IChYRU4pIFsgMTQw
OC4xMDc5MjVdICAgIFs8ZmZmZjgyZDA4MDEzNjQwMD5dIHRpbWVyLmMjdGltZXJfc29mdGlycV9h
Y3Rpb24rMHg5MC8weDIxMAo+IChYRU4pIFsgMTQwOC4xMTYyNjNdICAgIFs8ZmZmZjgyZDA4MDEz
MzExYz5dIHNvZnRpcnEuYyNfX2RvX3NvZnRpcnErMHg1Yy8weDkwCj4gKFhFTikgWyAxNDA4LjEy
MzkyMV0gICAgWzxmZmZmODJkMDgwMTY3ZDM1Pl0gZG9tYWluLmMjaWRsZV9sb29wKzB4MjUvMHg2
MAo+IAo+IEN1cnJlbnRseSBJJ20gdGVzdGluZyB0aGUgZm9sbG93aW5nIHBhdGNoIHRoYXQgZml4
ZXMgYXQgbGVhc3Qgb25lIHBvc3NpYmxlIAo+IHNjZW5hcmlvOgo+IAo+IGNvbW1pdCBmNzZkYzgz
MmMyZGU0OTUwODcyZmMyNzk2MmM1NmM2MDljZmYxMTYwCj4gQXV0aG9yOiBTZXJnZXkgRHlhc2xp
IDxzZXJnZXkuZHlhc2xpQGNpdHJpeC5jb20+Cj4gRGF0ZTogICBUdWUgRmViIDE0IDE1OjIzOjU0
IDIwMTcgKzAwMDAKPiAKPiAgICAgeDg2L3ZteDogdXNlIGN1cnJfdmNwdSBpbiB2bXhfdm1jc19l
eGl0KCkKPiAgICAgCj4gICAgIER1cmluZyBjb250ZXh0X3N3aXRjaCgpIGZyb20gYSBIVk0gdkNQ
VSB0byB0aGUgaWRsZSB2Q1BVLCBjdXJyZW50IGlzCj4gICAgIHVwZGF0ZWQgYnV0IGN1cnJfdmNw
dSByZXRhaW5zIHRoZSBITVYgdkNQVSdzIHZhbHVlLiAgSWYgYWZ0ZXIgdGhhdCwKPiAgICAgZm9y
IHNvbWUgcmVhc29uLCB2bXhfdm1jc19lbnRlcigpICsgdm14X3ZtY3NfZXhpdCgpIHBhaXIgd2ls
bCBiZQo+ICAgICBleGVjdXRlZCwgdGhlIHRlc3QgZm9yIGhhc19odm1fY29udGFpbmVyX3ZjcHUo
Y3VycmVudCkgd2lsbCBmYWlsIGFuZAo+ICAgICB2bWNzIGZvciBjdXJyX3ZjcHUgd2lsbCBub3Qg
YmUgbG9hZGVkLgoKSSdtIG5vdCBzZWVpbmcgdGhlIGNvbm5lY3Rpb24gdG8gdGhlIHdhdGNoZG9n
IGludm9jYXRpb24gYWJvdmU6CkkgdGFrZSBpdCB0aGF0IHZteF92bWNzX3JlbG9hZCgpIHdhcyBj
YXVnaHQgd2hpbGUgd2FpdGluZyBmb3IKYWN0aXZlX2NwdSB0byBiZWNvbWUgLTEuIFlldCB0aGF0
J3Mgd2hhdCB2bXhfY2xlYXJfdm1jcygpCmFjaGlldmVzLCBub3Qgdm14X2xvYWRfdm1jcygpLgoK
PiAgICAgVGhpcyB3aWxsIGxlYWQgdG8gQlVHKCkgZHVyaW5nIHRoZSBuZXh0IF9fY29udGV4dF9z
d2l0Y2goKSB3aGVuCj4gICAgIHZteF9jdHh0X3N3aXRjaF9mcm9tKCkgd2lsbCBiZSBleGVjdXRl
ZCBhbmQgX192bXdyaXRlKCkgd2lsbCBmYWlsLgoKQnV0IHRoYXQgY2FzZSBpcyBzcGVjaWZpY2Fs
bHkgKHN1cHBvc2VkIHRvIGJlKSB0YWtlbiBjYXJlIG9mIGJ5CmNhbGxpbmcgdm14X3ZtY3NfcmVs
b2FkKCkgZnJvbSB2bXhfY3R4dF9zd2l0Y2hfZnJvbSgpLgoKPiAgICAgRml4IHRoaXMgYnkgdGVz
dGluZyBoYXNfaHZtX2NvbnRhaW5lcl92Y3B1KCkgYWdhaW5zdCBjdXJyX3ZjcHUuCgpJZiBhdCBh
bGwgcG9zc2libGUsIEkgbGlrZSB0byBhdm9pZCBoYXZpbmcgdG8gdXNlIGN1cnJfdmNwdSBpbiB0
aGUgZml4aW5nCm9mIHRoaXMgKHdob2xlKSBpc3N1ZS4KCj4gLS0tIGEveGVuL2FyY2gveDg2L2h2
bS92bXgvdm1jcy5jCj4gKysrIGIveGVuL2FyY2gveDg2L2h2bS92bXgvdm1jcy5jCj4gQEAgLTc0
Miw2ICs3NDIsOCBAQCB2b2lkIHZteF92bWNzX2VudGVyKHN0cnVjdCB2Y3B1ICp2KQo+ICB2b2lk
IHZteF92bWNzX2V4aXQoc3RydWN0IHZjcHUgKnYpCj4gIHsKPiAgICAgIHN0cnVjdCBmb3JlaWdu
X3ZtY3MgKmZ2Owo+ICsgICAgdW5zaWduZWQgaW50IGNwdSA9IHNtcF9wcm9jZXNzb3JfaWQoKTsK
PiArICAgIHN0cnVjdCB2Y3B1ICpwID0gcGVyX2NwdShjdXJyX3ZjcHUsIGNwdSk7Cj4gIAo+ICAg
ICAgaWYgKCBsaWtlbHkodiA9PSBjdXJyZW50KSApCj4gICAgICAgICAgcmV0dXJuOwo+IEBAIC03
NTQsOCArNzU2LDggQEAgdm9pZCB2bXhfdm1jc19leGl0KHN0cnVjdCB2Y3B1ICp2KQo+ICAgICAg
ewo+ICAgICAgICAgIC8qIERvbid0IGNvbmZ1c2Ugdm14X2RvX3Jlc3VtZSAoZm9yIEB2IG9yIEBj
dXJyZW50ISkgKi8KPiAgICAgICAgICB2bXhfY2xlYXJfdm1jcyh2KTsKPiAtICAgICAgICBpZiAo
IGhhc19odm1fY29udGFpbmVyX3ZjcHUoY3VycmVudCkgKQo+IC0gICAgICAgICAgICB2bXhfbG9h
ZF92bWNzKGN1cnJlbnQpOwo+ICsgICAgICAgIGlmICggaGFzX2h2bV9jb250YWluZXJfdmNwdShw
KSApCj4gKyAgICAgICAgICAgIHZteF9sb2FkX3ZtY3MocCk7CgpJZiB0aGlzIGNoYW5nZSAob3Ig
c29tZXRoaW5nIHNpbWlsYXIpIHJlYWxseSB0dXJuZWQgb3V0IHRvIGJlCm5lY2Vzc2FyeSwgdGhl
IHZhcmlhYmxlIGRlY2xhcmF0aW9ucyBzaG91bGQgYmUgbW92ZWQgaW50byB0aGlzCm1vcmUgbmFy
cm93IHNjb3BlIChhbmQgSSdkIHByZWZlciB0aGUgImNwdSIgb25lIHRvIGJlIGRyb3BwZWQKYWx0
b2dldGhlcikuCgpKYW4KCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f
X19fX19fClhlbi1kZXZlbCBtYWlsaW5nIGxpc3QKWGVuLWRldmVsQGxpc3RzLnhlbi5vcmcKaHR0
cHM6Ly9saXN0cy54ZW4ub3JnL3hlbi1kZXZlbAo=