From mboxrd@z Thu Jan 1 00:00:00 1970 From: Razvan Cojocaru Subject: Re: Issues with the xen-access.c model Date: Wed, 6 Apr 2016 19:08:53 +0300 Message-ID: <57053495.5010002@bitdefender.com> References: <570399A2.4090507@bitdefender.com> <5703ABF3.4040709@citrix.com> <5703DFF7.6040108@bitdefender.com> <5703E385.4060904@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <5703E385.4060904@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" To: Andrew Cooper , Tamas K Lengyel Cc: "xen-devel@lists.xen.org" List-Id: xen-devel@lists.xenproject.org T24gMDQvMDUvMjAxNiAwNzoxMCBQTSwgQW5kcmV3IENvb3BlciB3cm90ZToKPiBPbiAwNS8wNC8x NiAxNjo1NSwgUmF6dmFuIENvam9jYXJ1IHdyb3RlOgo+PiBPbiAwNC8wNS8xNiAxODozNSwgVGFt YXMgSyBMZW5neWVsIHdyb3RlOgo+Pj4KPj4+IE9uIFR1ZSwgQXByIDUsIDIwMTYgYXQgNjoxMyBB TSwgQW5kcmV3IENvb3BlciA8YW5kcmV3LmNvb3BlcjNAY2l0cml4LmNvbQo+Pj4gPG1haWx0bzph bmRyZXcuY29vcGVyM0BjaXRyaXguY29tPj4gd3JvdGU6Cj4+Pgo+Pj4gICAgIE9uIDA1LzA0LzE2 IDExOjU1LCBSYXp2YW4gQ29qb2NhcnUgd3JvdGU6Cj4+PiAgICAgPiBIZWxsbywKPj4+ICAgICA+ Cj4+PiAgICAgPiB4ZW4tYWNjZXNzLmMgZG9lcyByb3VnaGx5IHRoaXM6Cj4+PiAgICAgPgo+Pj4g ICAgID4gZm9yICg7Oykgewo+Pj4gICAgID4gICAgICAgcG9sbF9ldnRfY2hhbm5lbCgpOwo+Pj4g ICAgID4KPj4+ICAgICA+ICAgICAgIGlmIChuZXdfZXZlbnRzKSB7Cj4+PiAgICAgPiAgICAgICAg ICAgICAgIHdoaWxlIChyaW5nX2J1ZmZlcl9oYXNfcmVxdWVzdHMpIHsKPj4+ICAgICA+ICAgICAg ICAgICAgICAgICAgICAgICBwdWxsX3JlcXVlc3QoKTsKPj4+ICAgICA+ICAgICAgICAgICAgICAg ICAgICAgICBwcm9jZXNzX3JlcXVlc3QoKTsKPj4+ICAgICA+ICAgICAgICAgICAgICAgICAgICAg ICBwdXRfcmVzcG9uc2UoKTsKPj4+ICAgICA+ICAgICAgICAgICAgICAgfQo+Pj4gICAgID4KPj4+ ICAgICA+ICAgICAgICAgICAgICAgc2lnbmFsX2V2dF9jaGFubmVsKCk7Cj4+PiAgICAgPiAgICAg ICB9Cj4+PiAgICAgPiB9Cj4+PiAgICAgPgo+Pj4gICAgID4gVGhlIHByb2JsZW1zIGFyZSB0aGVz ZToKPj4+ICAgICA+Cj4+PiAgICAgPiAxLiB2bV9ldmVudF9wdXRfcmVxdWVzdCgpIGRvZXMgbm90 aWZ5X3ZpYV94ZW5fZXZlbnRfY2hhbm5lbChkLAo+Pj4gICAgID4gdmVkLT54ZW5fcG9ydCk7IGF0 IHRoZSB2ZXJ5IGVuZCwgYW5kIHdlIHNlZW0gdG8gYmUgdXNpbmcgYSBGSUZPIGV2ZW50Cj4+PiAg ICAgPiBjaGFubmVsIChpZiBJJ20gcmVhZGluZyB0aGUgY29kZSByaWdodCwgaXQncyBnZW5lcmlj IGV2ZW50IGNoYW5uZWwKPj4+ICAgICBjb2RlCj4+PiAgICAgPiB0aGF0IHByZS1kYXRlcyB0aGUg dm1fZXZlbnQgY29kZSB0aGF0IHNpdHMgb24gdG9wIG9mIGl0KS4KPj4+ICAgICA+Cj4+PiAgICAg PiBUaGlzIG1lYW5zIHRoYXQgZm9yIGEgZ3Vlc3QgdGhhdCdzIHJ1bm5pbmcgdHdvIFZDUFVzLCB0 aGUgZm9sbG93aW5nCj4+PiAgICAgPiBzY2VuYXJpbyBpcyBwb3NzaWJsZToKPj4+ICAgICA+Cj4+ PiAgICAgPiAqIFZDUFUxIHB1dHMgYW4gZXZlbnQgaW4gdGhlIHJpbmcgYnVmZmVyCj4+PiAgICAg PiAqIFZDUFUxIHNpZ25hbHMgdGhlIGV2ZW50IGNoYW5uZWwKPj4+ICAgICA+ICogcG9sbF9ldnRf Y2hhbm5lbCgpIHdha2VzIHVwCj4+PiAgICAgPiAqIFZDUFUyIHB1dHMgYW4gZXZlbnQgaW4gdGhl IHJpbmcgYnVmZmVyCj4+PiAgICAgPiAqIHRoZSBsb29wIHByb2Nlc3NlcyB0aGUgZmlyc3QgZXZl bnQKPj4+ICAgICA+ICogVkNQVTIgc2lnbmFscyB0aGUgZXZlbnQgY2hhbm5lbAo+Pj4gICAgID4g KiB0aGUgbG9vcCBwcm9jZXNzZXMgdGhlIHNlY29uZCBldmVudCAoc2luY2UgdGhlcmUgX2FyZV8g bW9yZSByZXF1ZXN0cwo+Pj4gICAgID4gaW4gdGhlIHJpbmcgYnVmZmVyKQo+Pj4gICAgID4gKiB0 aGUgbG9vcCBzaWduYWxzIHRoZSBldmVudCBjaGFubmVsIHRoYXQgcmVxdWVzdHMgaGF2ZSBiZWVu IHByb2Nlc3NlZAo+Pj4gICAgID4gKiBwb2xsX2V2dF9jaGFubmVsKCkgd2FrZXMgdXAgYWdhaW4s IGJlY2F1c2Ugb2YgdGhlIHNlY29uZCBldmVudAo+Pj4gICAgIGNoYW5uZWwKPj4+ICAgICA+IHNp Z25hbCwgYnV0IHRoaXMgaXMgcG9pbnRsZXNzIHNpbmNlIGFsbCBldmVudHMgaGF2ZSBhbHJlYWR5 IGJlZW4KPj4+ICAgICBwcm9jZXNzZWQKPj4+ICAgICA+Cj4+PiAgICAgPiBUaGlzIGNhbiBiZSBh dm9pZGVkIGJ5IGNvdW50aW5nIHRoZSByZXF1ZXN0cyBwcm9jZXNzZWQgdnMuIHRoZQo+Pj4gICAg IG51bWJlciBvZgo+Pj4gICAgID4gc3VjY2VzZnVsIHBvbGwoKXMsIGJ1dCBpdCBzdGlsbCBkb2Vz IG5vdCBzb2x2ZSB0aGUgc2Vjb25kIHByb2JsZW06Cj4+PiAgICAgPgo+Pj4gICAgID4gMi4gUmFj ZSBjb25kaXRpb25zLiBBdCBsZWFzdCBpbiB0aGVvcnksIHRoZXJlJ3Mgbm90aGluZyB0byBzdG9w IHRoZQo+Pj4gICAgID4gc2Vjb25kIGl0ZXJhdGlvbiBvZiB0aGUgcmVxdWVzdCBwcm9jZXNzaW5n IGxvb3AgdG8gcmVhZCBhIHBhcnRpYWxseQo+Pj4gICAgID4gd3JpdHRlbiByZXF1ZXN0IGZyb20g dGhlIHJpbmcgYnVmZmVyLCBvciBnYXJiYWdlIGxlZnQgb3ZlciBmcm9tIGEKPj4+ICAgICA+IHBy ZXZpb3VzIHJlcXVlc3QsIGlmIGl0IGhpdHMgaXQgImp1c3QgcmlnaHQiIChpLmUuIHRoZSAiVkNQ VTIgcHV0cyBhbgo+Pj4gICAgID4gZXZlbnQgaW4gdGhlIHJpbmcgYnVmZmVyIiBwYXJ0IGNhbiBy dW4gb24gdG9wIG9mIHRoZSAidGhlIGxvb3AKPj4+ICAgICBwcm9jZXNzZXMKPj4+ICAgICA+IHRo ZSBzZWNvbmQgZXZlbnQiKS4KPj4+ICAgICA+Cj4+PiAgICAgPiBBbGwgdGhpcyBkb2Vzbid0IHJl YWxseSBzaG93IHVwIHVubGVzcyB3ZSdyZSBpbiBoZWF2eSBwcm9jZXNzaW5nCj4+PiAgICAgPiBz Y2VuYXJpb3MsIGJ1dCB0aGV5IGNhbiBvY2N1ciwgZXNwZWNpYWxseSBpbiBzeW5jZWQgdm1fZXZl bnQKPj4+ICAgICBzY2VuYXJpb3MuCj4+PiAgICAgPgo+Pj4gICAgID4gVGhlIHByb2JsZW1zIHNl ZW1zIHRvIGJlIGFsbGV2aWF0ZWQgYnkgY2hhbmdpbmcgdGhlIGxvb3AgdG8gdGhpczoKPj4+ICAg ICA+Cj4+PiAgICAgPiBmb3IgKDs7KSB7Cj4+PiAgICAgPiAgICAgICBwb2xsX2V2dF9jaGFubmVs KCk7Cj4+PiAgICAgPgo+Pj4gICAgID4gICAgICAgaWYgKG5ld19ldmVudHMpIHsKPj4+ICAgICA+ ICAgICAgICAgICAgICAgd2hpbGUgKHJpbmdfYnVmZmVyX2hhc19yZXF1ZXN0cykgewo+Pj4gICAg ID4gICAgICAgICAgICAgICAgICAgICAgIHB1bGxfcmVxdWVzdCgpOwo+Pj4gICAgID4gICAgICAg ICAgICAgICAgICAgICAgIHByb2Nlc3NfcmVxdWVzdCgpOwo+Pj4gICAgID4gICAgICAgICAgICAg ICAgICAgICAgIHB1dF9yZXNwb25zZSgpOwo+Pj4gICAgID4KPj4+ICAgICA+ICAgICAgICAgICAg ICAgICAgICAgICAvKiBNb3ZlZCBoZXJlLiAqLwo+Pj4gICAgID4gICAgICAgICAgICAgICAgICAg ICAgIHNpZ25hbF9ldnRfY2hhbm5lbCgpOwo+Pj4KPj4+Cj4+PiBUaGF0IHdhcyB0aGUgb3JpZ2lu YWwgc2V0dXAsIEkndmUgY2hhbmdlZCBpdCBhIHdoaWxlIGJhY2sgYnkgbW92aW5nIGl0Cj4+PiBv dXRzaWRlIHRoZSBsb29wLiBNeSByZWFzb25pbmcgd2FzIHRoYXQgdGhlcmUgaXMgbm8gcG9pbnQg aW4gZ29pbmcKPj4+IGxvY2tzdGVwIHdpdGggZXZlbnRzIGFuZCBpc3N1aW5nIGEgaHlwZXJjYWxs IGFmdGVyIGVhY2ggaXMgcHJvY2Vzc2VkLgo+Pj4gV2l0aCBvbmx5IGEgaGFuZGZ1bCBvZiBldmVu dHMgb24gdGhlIHJpbmcgdGhlIGNvbnRleHQgc3dpdGNoIGlzIHByb2JhYmx5Cj4+PiBtb3JlIHRh eGluZyB0aGVuIGhhdmluZyBhbGwgcmVxdWVzdHMgYW5kIHJlc3BvbnNlcyBwcm9jZXNzZWQgaW4g b25lCj4+PiBzd2lwZS4gT2YgY291cnNlLCBkZXBlbmRpbmcgb24gdGhlIGFwcGxpY2F0aW9uIHRo aXMgbWF5IG5vdCBiZSB0aGUKPj4+IG9wdGltYWwgY2FzZSBhbmQgdGhlIHNpZ25hbCBjYW4gYmUg bW92ZWQgYmFjayB0byB0aGUgbG9vcCAod2l0aCBsb3RzIG9mCj4+PiB2Q1BVcyBpdCBtYXkgYmUg dGhlIGNhc2UgdGhhdCB0aGUgZmlyc3QgdkNQVSByZW1haW5zIHBhdXNlZCB3aGlsZSBhbGwKPj4+ IGV2ZW50cyBhcmUgcHJvY2Vzc2VkIGZvciB0aGUgb3RoZXIgdkNQVXMsIHdoaWNoIG9mIGNvdXJz ZSB3b3VsZCBiZSBiYWQpLgo+Pj4gIAo+Pj4KPj4+ICAgICA+ICAgICAgICAgICAgICAgfQo+Pj4g ICAgID4gICAgICAgfQo+Pj4gICAgID4gfQo+Pj4gICAgID4KPj4+ICAgICA+IGJ1dCBpdCdzIG9i dmlvdXNseSBub3QgZm9vbHByb29mLCB0aGUgbWFpbiBwcm9ibGVtIHJlbWFpbmluZyB0aGUKPj4+ ICAgICA+IHN5bmNocm9uaXphdGlvbiBvZiB0aGUgcmluZyBidWZmZXIgZnJvbSBib3RoIHRoZSBo eXBlcnZpc29yIHNpZGUgYW5kCj4+PiAgICAgPiB1c2Vyc3BhY2UuCj4+PiAgICAgPgo+Pj4gICAg ID4gSG93IHNob3VsZCB3ZSBwcm9jZWVkIHRvIGZpeCB0aGlzPwo+Pj4KPj4+ICAgICBUaGUgdm1f ZXZlbnQgY29kZSBpbiBYZW4gbXVzdCBpbmNyZW1lbnQgdGhlIHByb2R1Y2VyIGluZGV4IGFzIHRo ZSBmaW5hbAo+Pj4gICAgIGFjdGlvbiBvZiBwdXR0aW5nIGEgcmVxdWVzdCBvbiB0aGUgcmluZy4g IElmIGl0IGRvZXNuJ3QgdGhlbiBpdCBpcwo+Pj4gICAgIHNpbXBseSBicm9rZW4gYW5kIG5lZWRz IGZpeGluZy4KPj4+Cj4+PiAgICAgVGhpcyB3aWxsIGVuc3VyZSB0aGF0IHRoZSBjb25zdW1lciBu ZXZlciBzZWVzIGEgcGFydGlhbCByZXF1ZXN0IG9uIHRoZQo+Pj4gICAgIHJpbmc7IGJ5IHRoZSB0 aW1lIGl0IG9ic2VydmVzIGEgbmV3ZXIgcHJvZHVjZXIgaW5kZXgsIGFsbCBkYXRhIGlzCj4+PiAg ICAgYWxyZWFkeSB3cml0dGVuLgo+Pj4KPj4+Cj4+PiBJdCBtYXkgd29ydGggZG91YmxlLWNoZWNr aW5nIGJ1dCBJJ20gcHJldHR5IHN1cmUgdGhhdCdzIGhvdyBpdCB3b3Jrcwo+Pj4gcmlnaHQgbm93 IGFzIHRoYXQgcGFydCBvZiB0aGUgY29kZSBoYXMgYmVlbiBwcmV0dHkgbXVjaCBqdXN0IGJlZW4K Pj4+IHJlY3ljbGVkIGZyb20gdGhlIG90aGVyIFhlbiByaW5nIGltcGxlbWVudGF0aW9ucy4KPj4g SSB1bmRlcnN0YW5kLiBXZSBzaG91bGRuJ3QgZm9yZ2V0IHRoYXQgdGhlIGNvbnN1bWVyIGFsc28g bW9kaWZpZXMgdGhlCj4+IHJpbmcgaW4gdXNlcnNwYWNlLCBhbmQgdGhlIGh5cGVydmlzb3IgdGhl biBiZWNvbWVzIGEgY29uc3VtZXIgb2YKPj4gcmVzcG9uc2VzLCBhbmQgdGhlIHNhbWUgaXNzdWVz IGFwcGx5IHRvIGl0ICh3b3VsZCBjb21waWxlciBvcHRpbWl6YXRpb25zCj4+IGJlIGEgcHJvYmxl bSBoZXJlPykuCj4gCj4gUXVpdGUgcG9zc2libHkuICBTZWUgWFNBLTE1NQo+IAo+PiBCdXQgdW5s ZXNzIHRoYXQncyB0aGUgY2FzZSwgdGhlbiBJJ20gcHJvYmFibHkgc2VlaW5nIGEgZGlmZmVyZW50 IGlzc3VlIGFuZCBBbmRyZXcgaXMgcmlnaHQuCj4+Cj4+IFRoYW5rIHlvdSBib3RoIGZvciB0aGUg cHJvbXB0IHJlcGxpZXMhCj4gCj4gWW91IG5lZWQgdG8gbWFrZSBjZXJ0YWluIHRoYXQgZm9yIGJv dGggcHJvZHVjZXIvY29uc3VtZXIgcGFpcnMsIHRoZQo+IGZvbGxvd2luZyBpcyB0cnVlOgo+IAo+ IFRoZSBwcm9kdWNlciBhbmQgY29uc3VtZXIgaW5kaWNlcyBhcmUgcmVhZCB1c2luZyBzb21lIGZv cm0gb2YgYXRvbWljCj4gb3BlcmF0aW9uIChBQ0NFU1NfT05DRSgpIG1vc3QgbGlrZWx5LCBvciBy ZWFkX2F0b21pYygpKSwgZm9sbG93ZWQgYnkgYW4KPiBzbWJfcm1iKCkgdG8gZ3VhcmFudGVlIHRo YXQgdGhlIHJlYWQgY29tcGxldGVzIGFuZCBpcyBpbiBhIGxvY2FsCj4gdmFyaWFibGUgYmVmb3Jl IGFueSBjYWxjdWxhdGlvbiBpcyBwZXJmb3JtZWQgYmFzZWQgb24gdGhlIHZhbHVlLiAgKFRoaXMK PiBwcmV2ZW50cyB0aGUgY29tcGlsZXIgIm9wdGltaXNpbmciIHRvIG11bHRpcGxlIHJlYWRzIG9m IHRoZSBzaGFyZWQgcmluZykuCj4gCj4gVGhlbiwgbWVtY3B5KCkgKG9yIHN1aXRhYmxlIGFsdGVy bmF0aXZlKSB0byBnZXQgdGhlIGNvbnRlbnRzIG9mIHRoZQo+IHJlcXVlc3QgaW4vb3V0IG9mIHRo ZSByaW5nLgo+IAo+IEZvciB0aGUgcHJvZHVjZXIgc2lkZSwgYW4gc21wX3dtYigpIGJldHdlZW4g dGhlIG1lbWNweSgpIGludG8gdGhlIHJpbmcsCj4gYW5kIHRoZSB3cml0ZSB0byB0aGUgcHJvZHVj ZXIgaW5kZXguCj4gRm9yIHRoZSBjb25zdW1lciBzaWRlLCBhbiBzbXBfbWIoKSBiZXR3ZWVuIHRo ZSBtZW1jcHkoKSBvdXQgb2YgdGhlIHJpbmcsCj4gYW5kIHRoZSB3cml0ZSB0byB0aGUgY29uc3Vt ZXIgaW5kZXguCgpEaWQgYWxsIG9mIHRoYXQsIHRvIG5vIGF2YWlsIC0gYnV0IHRoZSBpc3N1ZSBt YXkgaW5kZWVkIGJlIHNvbWV3aGVyZSBlbHNlLgoKV2hhdCBJJ20gc2VlaW5nIGlzIHRoYXQgb24g V2luZG93cyA3IHg4NiBib290LCBhdCB0aGUgcG9pbnQgb2YgbG9hZGluZwpzb21lIGRyaXZlcnMg KG1vc3Qgb2Z0ZW4gYXJvdW5kIHVzYnBvcnQuc3lzKSwgaWYgSSBnZXQgcGFnZSBmYXVsdHMgaW4K cXVpY2sgc3VjY2Vzc2lvbiBhbmQgdHJ5IHRvIGVtdWxhdGUgdGhlIG9mZmVuZGluZyBpbnN0cnVj dGlvbiB3aXRoIGNvZGUKc2ltaWxhciB0byB0aGUgeGVuLWFjY2Vzcy5jICJvdXRzaWRlLXRoZS1s b29wIHJlc3VtZSIgbW9kZWwsIHRoZSBkb21VCmFwcGVhcnMgdG8gZnJlZXplIChhbHRob3VnaCBp dCdzIHN0aWxsIHJ1bm5pbmcgYW5kIG5vdGhpbmcgY3Jhc2hlcykuIHg2NApndWVzdHMgc2VlbSB1 bmFmZmVjdGVkIGJ5IHRoaXMsIGFuZCB4ODYgZ3Vlc3RzIGFsbW9zdCBuZXZlciBoYW5nIGlmIEkK cHV0IHRoZSByZXN1bWUgY29kZSBpbnNpZGUgdGhlIGxvb3AuCgpUaGlzIGJlaGF2aW91ciBpcyBh bHdheXMgYWNjb21wYW5pZWQgYnkgcWVtdS1kbSBnb2luZyB0byAxMDAlIENQVSBmb3IgYQpmZXcg bWludXRlcy4gSXQgZXZlbnR1YWxseSBzdWJzaWRlcywgYnV0IHRoZSBndWVzdCByZW1haW5zIHVu dXNhYmxlCmFsdGhvdWdoIGl0J3Mgbm90IGRlYWQuCgpUaGlzIGdvZXMgYXdheSBpZiBJIGp1c3Qg cnVuIHRoZSBpbnN0cnVjdGlvbiAod2l0aCBhIHNpbmdsZS1zdGVwLWxpa2UKbW9kZWwpIGluc2lk ZSB0aGUgaHlwZXJ2aXNvciBpbnN0ZWFkIG9mIHRyeWluZyB0byBlbXVsYXRlIGl0LCB0aGlzIGJl aW5nCnRoZSBvbmx5IGNoYW5nZS4KClVuZm9ydHVuYXRlbHkgdGhpcyBpcyBub3QgdHJpdmlhbCB0 byBkZW1vbnN0cmF0ZSB3aXRoIHNtYWxsCm1vZGlmaWNhdGlvbnMgdG8gdGhlIFhlbiBpbi10cmVl IGNvZGUgKHNlZSB0aGUgQ0xJIGVtdWxhdGlvbiBpc3N1ZSwgZm9yCmV4YW1wbGUpLgoKV291bGQg dHJ5aW5nIHRvIGVtdWxhdGUgYW4gaW5zdHJ1Y3Rpb24gZnJvbSBhIGRyaXZlciB3b3JraW5nIHdp dGggcWVtdQpjYXVzZSB0aGlzPyBObyBlbXVsYXRpb24gZmFpbHVyZXMgYXJlIHJlcG9ydGVkLCBi dXQgdGhlIGF0dGVtcHQKYXBwYXJlbnRseSBsZWFkcyB0byBhKG4gSU8/KSBsb29wIG9mIHNvbWUg a2luZC4KCgpUaGFua3MsClJhenZhbgoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18KWGVuLWRldmVsIG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVu Lm9yZwpodHRwOi8vbGlzdHMueGVuLm9yZy94ZW4tZGV2ZWwK