Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753580Ab0DGCmG (ORCPT ); Tue, 6 Apr 2010 22:42:06 -0400 Received: from mga11.intel.com ([192.55.52.93]:54736 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212Ab0DGCl5 convert rfc822-to-8bit (ORCPT ); Tue, 6 Apr 2010 22:41:57 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.51,376,1267430400"; d="scan'208";a="555624365" From: "Xin, Xiaohui" To: "Michael S. Tsirkin" CC: "netdev@vger.kernel.org" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "mingo@elte.hu" , "jdike@c2.user-mode-linux.org" , "yzhao81@gmail.com" Date: Wed, 7 Apr 2010 10:41:08 +0800 Subject: RE: [PATCH 1/3] A device for zero-copy based on KVM virtio-net. Thread-Topic: [PATCH 1/3] A device for zero-copy based on KVM virtio-net. Thread-Index: AcrRjDzWloLq/tseTwCC82REc7j2hQEbxINg Message-ID: <97F6D3BD476C464182C1B7BABF0B0AF5C183234A@shzsmsx502.ccr.corp.intel.com> References: <20100308112849.GI7482@redhat.com> <1270114038-5048-1-git-send-email-xiaohui.xin@intel.com> <20100401110841.GE3323@redhat.com> In-Reply-To: <20100401110841.GE3323@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 550 Lines: 16 Michael, >> Qemu needs a userspace write, is that a synchronous one or >>asynchronous one? >It's a synchronous non-blocking write. Sorry, why the Qemu live migration needs the device have a userspace write? how does the write operation work? And why a read operation is not cared here? Thanks Xiaohui -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/