From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53260) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7jx8-0008Hh-MS for qemu-devel@nongnu.org; Fri, 09 Aug 2013 06:30:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V7jx0-00020x-AI for qemu-devel@nongnu.org; Fri, 09 Aug 2013 06:29:50 -0400 Received: from mail-ee0-x233.google.com ([2a00:1450:4013:c00::233]:65086) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V7jx0-00020p-4d for qemu-devel@nongnu.org; Fri, 09 Aug 2013 06:29:42 -0400 Received: by mail-ee0-f51.google.com with SMTP id c1so2007874eek.38 for ; Fri, 09 Aug 2013 03:29:41 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <5204C475.2040905@redhat.com> Date: Fri, 09 Aug 2013 12:29:09 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1376038150-14527-1-git-send-email-aik@ozlabs.ru> <5204B8F9.5050201@redhat.com> <1376043659.32100.37.camel@pasglop> In-Reply-To: <1376043659.32100.37.camel@pasglop> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] pci: Introduce helper to retrieve a PCI device's DMA address space List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Benjamin Herrenschmidt Cc: Alexey Kardashevskiy , Anthony Liguori , David Gibson , qemu-devel@nongnu.org, "Michael S . Tsirkin" Il 09/08/2013 12:20, Benjamin Herrenschmidt ha scritto: > On Fri, 2013-08-09 at 11:40 +0200, Paolo Bonzini wrote: >> (BTW, do you need to enable bus-master DMA on PCI bridges, to do DMA >> for devices sitting on the secondary bus?) > > In theory yes though I have seen bridges who ignore it... And we would need a compatibility property anyway. So let's choose to be among the ones who ignore it (i.e. the same as this patch). But it needs a comment. Paolo