From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58532) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a8X1u-0005nZ-Bi for qemu-devel@nongnu.org; Mon, 14 Dec 2015 12:35:23 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a8X1q-0003pU-Du for qemu-devel@nongnu.org; Mon, 14 Dec 2015 12:35:22 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48514) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a8X1q-0003oc-8c for qemu-devel@nongnu.org; Mon, 14 Dec 2015 12:35:18 -0500 Date: Mon, 14 Dec 2015 19:35:14 +0200 From: "Michael S. Tsirkin" Message-ID: <20151214193220-mutt-send-email-mst@redhat.com> References: <1449994112-7054-1-git-send-email-shmulik.ladkani@ravellosystems.com> <1449994112-7054-7-git-send-email-shmulik.ladkani@ravellosystems.com> <566EF753.4070605@redhat.com> <20151214190935-mutt-send-email-mst@redhat.com> <163895392.40236889.1450114130220.JavaMail.zimbra@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <163895392.40236889.1450114130220.JavaMail.zimbra@redhat.com> Subject: Re: [Qemu-devel] [PATCH v2 6/6] vmw_pvscsi: Introduce 'x-disable-pcie' backword compatability property List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Dmitry Fleytman , Marcel Apfelbaum , idan brown , Shmulik Ladkani , qemu-devel@nongnu.org On Mon, Dec 14, 2015 at 12:28:50PM -0500, Paolo Bonzini wrote: > > Well qapi/qmp docs say things like: > > > > Any name (command, event, type, field, or enum value) beginning with > > "x-" is marked experimental, and may be withdrawn or changed > > incompatibly in a future release. > > > > It's thus reasonable to use this for internal properties, > > that we don't want users to play with. > > What distinguishes an internal from an external property? Everything > except links to backends would be "internal". How do you mean? We have a ton of properties e.g. to control which offloads are allowed for virtio net. Internal are properties which are not there for users, performing some technical function instead. > We've used a much more restrictive definition so far than that---basically > known-broken or debugging-only---and I think it's more appropriate. > > > BTW, we probably should teach -help to hide these options by default. > > Please, no obscuring of functionality. Debugging-only functionality > definitely belongs in -help. > > Paolo Sure. This option is not for debugging though. It's set internally by machine types to avoid breaking migration. I don't see any reason for users to set it. -- MST