From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:32960) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cZhLq-0005lz-UX for qemu-devel@nongnu.org; Fri, 03 Feb 2017 12:08:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cZhLm-0003Ls-Tu for qemu-devel@nongnu.org; Fri, 03 Feb 2017 12:08:46 -0500 Received: from mail-wm0-x242.google.com ([2a00:1450:400c:c09::242]:35839) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cZhLm-0003LW-N4 for qemu-devel@nongnu.org; Fri, 03 Feb 2017 12:08:42 -0500 Received: by mail-wm0-x242.google.com with SMTP id u63so5633693wmu.2 for ; Fri, 03 Feb 2017 09:08:42 -0800 (PST) Sender: Paolo Bonzini References: <20170202150530.1025-1-pbonzini@redhat.com> <20170203150050.GF642@stefanha-x1.localdomain> From: Paolo Bonzini Message-ID: <55b46fa3-c861-9ba4-da65-25bc392d8900@redhat.com> Date: Fri, 3 Feb 2017 09:08:36 -0800 MIME-Version: 1.0 In-Reply-To: <20170203150050.GF642@stefanha-x1.localdomain> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [RFC PATCH] configure: remove --enable-replication/--disable-replication List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: qemu-devel@nongnu.org, dgilbert@redhat.com On 03/02/2017 07:00, Stefan Hajnoczi wrote: > On Thu, Feb 02, 2017 at 07:05:30AM -0800, Paolo Bonzini wrote: >> The replication feature is a small amount of code, does not >> require any external library and unless used does not add >> anything to the guest's attack surface. Since any extra >> configure option affects maintainability on the other hand >> and is subject to bit rot, I think there is no need to >> make it configurable. > > I think the current state is good: replication is enabled by default but > can be compiled out if desired. > > Downstreams may not be comfortable supporting this feature yet since > it's incomplete. It's fair to offer an option to disable it, otherwise > downstreams will have to patch this themselves. I understand---I just am not sure where to draw the line because there's plenty of other incomplete features, hence the RFC. For example, record/replay cannot be enabled or disabled on the configure command line. That was the case even in the beginning, where it didn't support either block or character device replay. --enable-coroutine-pool is a relic of when Windows builds needed it, but all other --enable-* options require an external library or at least a specific operating system. See for example this patch: commit 52b53c04faab9f7a9879c8dc014930649a3e698d Author: Fam Zheng Date: Wed Sep 10 14:17:51 2014 +0800 block: Always compile virtio-blk dataplane Dataplane doesn't depend on linux-aio any more, so we don't need the compiling condition now. Configure options are kept but just print a message. Signed-off-by: Fam Zheng Reviewed-by: Paolo Bonzini Message-id: 1410329871-28885-4-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi I would actually prefer to remove many of the latter (--enable-vhost-net, --enable-vhost-scsi, --enable-vhost-socket) and just use default-configs. We are already doing it for ivshmem for example: CONFIG_IVSHMEM=$(CONFIG_EVENTFD) Paolo