From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: INDIRECT and NEXT Date: Fri, 23 Oct 2009 11:30:21 +0200 Message-ID: <20091023093021.GB13401@redhat.com> References: <20091004143734.GB17578@redhat.com> <200910231401.24419.rusty@rustcorp.com.au> <20091023063648.GC10821@redhat.com> <200910231950.31241.rusty@rustcorp.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <200910231950.31241.rusty@rustcorp.com.au> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Rusty Russell Cc: virtualization@lists.osdl.org List-Id: virtualization@lists.linuxfoundation.org On Fri, Oct 23, 2009 at 07:50:31PM +1030, Rusty Russell wrote: > On Fri, 23 Oct 2009 05:06:48 pm Michael S. Tsirkin wrote: > > On Fri, Oct 23, 2009 at 02:01:23PM +1030, Rusty Russell wrote: > > > Also, we have a limitation that you can't have more descriptors than the ring > > > size, even with indirect, due to overzealous checks... > > > > Yes ... so I wonder: do we want to fix all this and add a feature bit, > > or wait until some guest actually wants to use such descriptors? > > Yes, we wait until someone wants it. Then (1) we have a test case, and > (2) we can make sure we don't do those (bogus, frankly) >= ringsize checks. OK. But for vhost, there's no reason not to do it right directly, right? guests won't depend on undefined behaviour. -- MST