From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55137) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c6BUH-0004fK-HX for qemu-devel@nongnu.org; Mon, 14 Nov 2016 02:15:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c6BUE-0000e6-9B for qemu-devel@nongnu.org; Mon, 14 Nov 2016 02:15:29 -0500 Received: from mail-pg0-f66.google.com ([74.125.83.66]:33367) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1c6BUE-0000du-0M for qemu-devel@nongnu.org; Mon, 14 Nov 2016 02:15:26 -0500 Received: by mail-pg0-f66.google.com with SMTP id 3so8249965pgd.0 for ; Sun, 13 Nov 2016 23:15:25 -0800 (PST) Date: Mon, 14 Nov 2016 15:14:46 +0800 From: "zhunxun@gmail.com" References: <201611051850530152761@gmail.com>, , , , <201611091858142738325@gmail.com>, <20161110103253.GC17332@stefanha-x1.localdomain>, <2016111020163477037720@gmail.com>, <20161111120347.GB8930@stefanha-x1.localdomain> Mime-Version: 1.0 Message-ID: <201611141514445356426@gmail.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: base64 Subject: Re: [Qemu-devel] virtIO question List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi , qemu SGVsbG/vvIx0ZWFjaGVyLEkgbWF5IGJlIGZvdW5kIHdoZXJlIHRoZSBkcml2ZXIgYWRkIG11dGlw bGUgYnVmZmVyIHRvIHZpcnRxdWV1ZSBhbmQgdGhlbiBraWNrIHFlbXUgc2lkZS4gSXQgaXMgd2hl biBkcml2ZXIgdXNlIE5BUEkgdG8gcG9sbCB0aGUgZGV2aWNlIHRvIGdldCBidWZmZXJzLGFuZCBp dCBpcyBpbiByZWNlaXZlIHF1ZXVlLmJ1dCBpbiB0cmFuc21pdCBxdWV1ZSxldmVyeSB0aW1lIGRy aXZlciBhZGQgYSBidWZmZXIgdG8gdmlydHF1ZXVlLHRoZW4ga2ljayBmdW5jdGlvbiBpcyBjYWxs ZWQhISF3aHkgPz9pcyBxZW11IGhhbmRsZSBidWZmZXIgZmFzdGVyIHRoYW4gZHJpdmVyIGFkZCBp dD8/DQoNCnRoYW5rIHlvdSB2ZXJ5IG11Y2ghDQoNCg0KDQp6aHVueHVuQGdtYWlsLmNvbQ0KIA0K RnJvbTogU3RlZmFuIEhham5vY3ppDQpEYXRlOiAyMDE2LTExLTExIDIwOjAzDQpUbzogemh1bnh1 bkBnbWFpbC5jb20NCkNDOiBxZW11DQpTdWJqZWN0OiBSZTogUmU6IFtRZW11LWRldmVsXSB2aXJ0 SU8gcXVlc3Rpb24NCk9uIFRodSwgTm92IDEwLCAyMDE2IGF0IDA4OjE2OjM4UE0gKzA4MDAsIHpo dW54dW5AZ21haWwuY29tIHdyb3RlOg0KPiBGcm9tIHRoaXMgcG9pbnQgb2YgdmlldyAsSSB0aGlu ayBpdCBtYWtlIHNlbnNlIHdlbGwsIHRoYW5rIHlvdSB2ZXJ5IG11Y2ghDQo+ICBidXQgSSBoYXZl IGFub3RoZXIgcXVlc3Rpb24gYWJvdXQgbm90aWZ5IG1lY2hhbmlzbSBiZXR3ZWVuIHZpcnRJTyBk cml2ZXIgYW5kIHFlbXUuDQo+IGFjY29yZGluZyB0aGUgc291cmNlIGNvZGUgb2YgTGludXggYW5k IHFlbXUsDQo+IHdoZW4gZHJpdmVyIGFkZCBhIHNnIGJ1ZmZlciB0byBzZW5kIHF1ZXVlIG5hbWVk IHNxLA0KPiBzcS0+dnEtPnZyaW5nLmF2YWlsLT5pZHgrKw0KPiB2cS0+bnVtX2FkZGVkKysNCj4g YW5kIHRoZW4gdXNlIHZpcnRxdWV1ZV9raWNrX3ByZXBhcmUgdG8gbWFrZSBzdXJlIGlmIG5lZWQg bm90aWZ5IHFlbXUuDQo+IGl0IChuZXdfaWR4LWV2ZW50X2lkeCk8KG5ld19pZHgtb2xkX2lkeCkN CiANClRoaXMgZXhwcmVzc2lvbiBpcyB3cm9uZy4gIFRoZSBzcGVjaWZpY2F0aW9uIGFuZCBMaW51 eCBjb2RlIGJvdGggc2F5Og0KIA0KICAodTE2KShuZXdfaWR4IC0gZXZlbnRfaWR4IC0gMSkgPCAo dTE2KShuZXdfaWR4IC0gb2xkX2lkeCkNCiANCkJvdGggdGhlICh1MTYpIGFuZCB0aGUgLTEgbWF0 dGVyLiAgTWF5YmUgdGhhdCdzIHdoeSB5b3UgYXJlIGNvbmZ1c2VkIGJ5DQp0aGlzPw0KIA0KPiBp ZiBpdCBpcyB0cnVlLHRoZW4gbm90aWZ5IG90aGVyIHNpZGUuDQo+IEhvd2V2ZXIsZXZlcnkgdGlt ZSBkcml2ZXIgYWRkIGEgc2csdGhlbiB2aXJ0cXVldWVfa2lja19wcmVwYXJlIGlzIGNhbGxlZCxh bmQgdnEtPm51bV9hZGRlZCAgaXMgcmVzZXRlZCB0byAwLHNvIGluIGZhY3QgLEkgdGhpbmsgdnEt Pm51bV9hZGRlZCBpcyBhbHdheXMgMCBvciAx44CCDQogDQpBIGRyaXZlciBtYXkgYWRkIG11bHRp cGxlIGJ1ZmZlcnMgdG8gdGhlIHZpcnRxdWV1ZSBieSBjYWxsaW5nDQp2aXJ0cXVldWVfYWRkX3Nn cygpIG9yIHNpbWlsYXIgZnVuY3Rpb25zIG11bHRpcGxlIHRpbWVzIGJlZm9yZSBraWNraW5nLg0K VGhlcmVmb3JlIHZxLT5udW1fYWRkZWQgPiAxIGlzIHBvc3NpYmxlLg0KIA0KPiBhcyB0byBxZW11 IHNpZGUsZXZlcnkgdGltZSB3aGVuIHBvcCBhIGVsZW0gZnJvbSB2aXJ0cXVldWUsaXQgc2V0IFZS aW5nVXNlZC5yaW5nW3ZyaW5nLm51bV0gdG8gdGhlIGxhc3Rlc3QgVlJpbmdBdmFpbC5pZHgsIHRo aXMgYWNjb3JkaW5nIHRoZSBhcml0aG1ldGljICgobmV3X2lkeC1ldmVudF9pZHgpPChuZXdfaWR4 LW9sZF9pZHgpKSxpdCBzZWVtcyB0aGF0IHRoaXMgbWVjaGFuaXNtIGRvZXMgbm90IG1ha2Ugc2Vu c2UNCiANCllvdSBhcmUgYmFzaWNhbGx5IGFza2luZyAiaG93IGRvZXMgZXZlbnRfaWR4IHdvcms/ Ii4gIFRoZSBzcGVjaWZpY2F0aW9uDQpzYXlzOg0KIA0KICAiVGhlIGRyaXZlciBjYW4gYXNrIHRo ZSBkZXZpY2UgdG8gZGVsYXkgaW50ZXJydXB0cyB1bnRpbCBhbiBlbnRyeSB3aXRoDQogIGFuIGlu ZGV4IHNwZWNpZmllZCBieSB0aGUg4oCcdXNlZF9ldmVudOKAnSBmaWVsZCBpcyB3cml0dGVuIGlu IHRoZSB1c2VkIHJpbmcNCiAgKGVxdWl2YWxlbnRseSwgdW50aWwgdGhlIGlkeCBmaWVsZCBpbiB0 aGUgdXNlZCByaW5nIHdpbGwgcmVhY2ggdGhlDQogIHZhbHVlIHVzZWRfZXZlbnQgKyAxKS4iDQog DQphbmQ6DQogDQogICJUaGUgZGV2aWNlIGNhbiBhc2sgdGhlIGRyaXZlciB0byBkZWxheSBub3Rp 76yBY2F0aW9ucyB1bnRpbCBhbiBlbnRyeQ0KICB3aXRoIGFuIGluZGV4IHNwZWNpZmllZCBieSB0 aGUg4oCcYXZhaWxfZXZlbnTigJ0gZmllbGQgaXMgd3JpdHRlbiBpbiB0aGUNCiAgYXZhaWxhYmxl IHJpbmcgKGVxdWl2YWxlbnRseSwgdW50aWwgdGhlIGlkeCBmaWVsZCBpbiB0aGUgdXNlZCByaW5n IHdpbGwNCiAgcmVhY2ggdGhlIHZhbHVlIGF2YWlsX2V2ZW50ICsgMSkuIg0KIA0KV2hlbmV2ZXIg dGhlIGRldmljZSBvciBkcml2ZXIgd2FudHMgdG8gbm90aWZ5LCBpdCBmaXJzdCBjaGVja3MgaWYg dGhlDQppbmRleCB1cGRhdGUgY3Jvc3NlZCB0aGUgZXZlbnQgaW5kZXggc2V0IGJ5IHRoZSBvdGhl ciBzaWRlLg0K