From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com (mail-pa0-f43.google.com [209.85.220.43]) by dpdk.org (Postfix) with ESMTP id 93576532C for ; Tue, 27 Sep 2016 21:48:07 +0200 (CEST) Received: by mail-pa0-f43.google.com with SMTP id cd13so5324761pac.0 for ; Tue, 27 Sep 2016 12:48:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=yXyUPX6fzg+wFE+1nAKFT/KkiiaG3X9NFLs8E3sumKM=; b=ef0rHHoqqFLYiMP+pRPQKSnkEjSZETdZq5NLg8vWaxeflTvJyQUWSppY3EWPNdCUoL TqRz5575fU/cVn8OyZfQ/SJyvGR5CrndkLbSQN0iE70kcrA0vh+QQX4x4nh1YFXwtKif oUM2rKcEPPQZekkFMjdDShroHgYE9T8wc8NdxAy98C98C8/mUWs+aKFA72dhepnEbNpd J6LGmbTfAtSdh2p/ii7SEdZnYD59FesTJ8telXCYUsud3glwwAbCQJ3odmNaCrJFTU5X TPyIRPVPDJi7XNMfduAGmCC6LiIzZq8Xldq1Ac/KaVLpQ0ofyZOYTvslkP5MCL8TPo/l hhtw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=yXyUPX6fzg+wFE+1nAKFT/KkiiaG3X9NFLs8E3sumKM=; b=hi1Xz4yWX37Ddqd4CkSmEi+HDKxHi04EKweRSM68s76vzkwj9IbhMWwXuBmtT1u+xj 46E1PbZ5RFyb8moGON4HWnnjcAOPIrc3M09TC4Bbp7wyEksZrLCuu5iwNu3BSshtZaH8 O9FGTWHIpHZykkwepVfyrxpIuqYK3jDejaA8wbSU2MaPM+1a3CFR1jXsua9VH9H7kcNr sx1UIG9THDdUvU0GC4cX5D9aZhCCjyoyUckh7iZNJo6S22fEQ4SnKATGSYMWoyhMon+p RioDgzIxthjHFeKt5art5G/9bbFvPzGLOYwhnoJHTV3c0E/1X6qDlEClasFn7+1hzh+7 S8bw== X-Gm-Message-State: AA6/9RlNR0PqwCcScGBzabwADBINGj3QApCSVExU+6qHH5FXBCF+lXUAJnZiqrS1a0ilmg== X-Received: by 10.66.173.145 with SMTP id bk17mr11168971pac.8.1475005686978; Tue, 27 Sep 2016 12:48:06 -0700 (PDT) Received: from xeon-e3 (static-50-53-69-251.bvtn.or.frontiernet.net. [50.53.69.251]) by smtp.gmail.com with ESMTPSA id o123sm6790042pfg.78.2016.09.27.12.48.06 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 27 Sep 2016 12:48:06 -0700 (PDT) Date: Tue, 27 Sep 2016 12:48:18 -0700 From: Stephen Hemminger To: Yuanhan Liu Cc: "Michael S. Tsirkin" , Maxime Coquelin , dev@dpdk.org, qemu-devel@nongnu.org Message-ID: <20160927124818.3a37c7c1@xeon-e3> In-Reply-To: <20160927031158.GA25823@yliu-dev.sh.intel.com> References: <1474872056-24665-1-git-send-email-yuanhan.liu@linux.intel.com> <1474872056-24665-2-git-send-email-yuanhan.liu@linux.intel.com> <20160926221112-mutt-send-email-mst@kernel.org> <20160927031158.GA25823@yliu-dev.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH 1/2] vhost: enable any layout feature X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Sep 2016 19:48:08 -0000 On Tue, 27 Sep 2016 11:11:58 +0800 Yuanhan Liu wrote: > On Mon, Sep 26, 2016 at 10:24:55PM +0300, Michael S. Tsirkin wrote: > > On Mon, Sep 26, 2016 at 11:01:58AM -0700, Stephen Hemminger wrote: > > > I assume that if using Version 1 that the bit will be ignored > > Yes, but I will just quote what you just said: what if the guest > virtio device is a legacy device? I also gave my reasons in another > email why I consistently set this flag: > > - we have to return all features we support to the guest. > > We don't know the guest is a modern or legacy device. That means > we should claim we support both: VERSION_1 and ANY_LAYOUT. > > Assume guest is a legacy device and we just set VERSION_1 (the current > case), ANY_LAYOUT will never be negotiated. > > - I'm following the way Linux kernel takes: it also set both features. Agreed, just do what the Linux kernel does.