From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42557) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VOOQB-0001Fb-4h for qemu-devel@nongnu.org; Tue, 24 Sep 2013 04:56:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VOOQ5-0007FA-5U for qemu-devel@nongnu.org; Tue, 24 Sep 2013 04:56:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:16691) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VOOQ4-0007F0-Tv for qemu-devel@nongnu.org; Tue, 24 Sep 2013 04:56:33 -0400 Date: Tue, 24 Sep 2013 11:58:45 +0300 From: "Michael S. Tsirkin" Message-ID: <20130924085845.GA18980@redhat.com> References: <20130923112744.GC544@redhat.com> <1379939863.2050.35.camel@localhost.localdomain> <20130923134512.GD1278@redhat.com> <1379947418.2050.47.camel@localhost.localdomain> <20130923151014.GB2899@redhat.com> <1379958593.2050.58.camel@localhost.localdomain> <20130923184513.GB8717@redhat.com> <1380010039.2050.69.camel@localhost.localdomain> <20130924082936.GA18673@redhat.com> <1380012297.2050.78.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1380012297.2050.78.camel@localhost.localdomain> Subject: Re: [Qemu-devel] [PATCH] hw/pci: completed master-abort emulation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Marcel Apfelbaum Cc: peter.maydell@linaro.org, qemu-devel@nongnu.org, Anthony Liguori corrected Anthony's mail. On Tue, Sep 24, 2013 at 11:44:57AM +0300, Marcel Apfelbaum wrote: > > Not necessarily. Another bridge can claim it then > > terminate with MA. > > > > Example: > > > > -[0000:00]-+-00.0 > > +-02.0 > > +-16.0 > > +-16.3 > > +-19.0 > > +-1a.0 > > +-1b.0 > > +-1c.0-[02]-- > > +-1c.1-[03]----00.0 > > +-1c.3-[05-0c]-- > > +-1c.4-[0d]--+-00.0 > > | \-00.3 > > > > > > > > Device 03:00.0 writes to within memory window of 00:1c.4, > > but outside BARs of both 0d:00.0 and 0d:00.3. > > > > On PCI, I think MA is set in sec status register of 00:1c.4. > You are right, my code will work only under the assumption > that the devices do not communicate between them. > I will state the above in the next version. > > Thanks, > Marcel How hard is it to fix properly? If that's hard, would it be easier to implement express semantics unconditionally?