From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49433) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d5kOo-0005rN-UY for qemu-devel@nongnu.org; Tue, 02 May 2017 22:52:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d5kOl-0008VT-K7 for qemu-devel@nongnu.org; Tue, 02 May 2017 22:52:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57344) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d5kOl-0008UC-E5 for qemu-devel@nongnu.org; Tue, 02 May 2017 22:52:15 -0400 Date: Tue, 2 May 2017 20:52:11 -0600 From: Alex Williamson Message-ID: <20170502205211.5b9fd55b@t450s.home> In-Reply-To: <20170503024101.GA31494@pacoca> References: <1492631083-23965-1-git-send-email-joserz@linux.vnet.ibm.com> <20170420100301.51a7f10c@t450s.home> <07d71898-c392-c14a-9901-87ad4287bd5d@redhat.com> <20170503024101.GA31494@pacoca> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/2] VFIO: Make 8-byte accesses atomic List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: joserz@linux.vnet.ibm.com Cc: Paolo Bonzini , Richard Henderson , qemu-devel@nongnu.org, aik@ozlabs.ru, mdroth@linux.vnet.ibm.com On Tue, 2 May 2017 23:41:01 -0300 joserz@linux.vnet.ibm.com wrote: > On Fri, Apr 21, 2017 at 12:06:15PM +0200, Paolo Bonzini wrote: > > > > > > On 20/04/2017 18:03, Alex Williamson wrote: > > > On Thu, 20 Apr 2017 00:19:23 -0700 > > > Richard Henderson wrote: > > > > > >> On 04/19/2017 12:44 PM, Jose Ricardo Ziviani wrote: > > >>> This patchset has two patches: > > >>> [1] 8-byte writes to non-mapped MMIO are broken into pairs of 4-byte writes, this patch makes such pairs atomic. > > >>> > > >>> [2] Enable 8-byte accesses in vfio_region_write and vfio_region_read. > > >>> > > >>> Patches based on master. > > >>> > > >>> Jose Ricardo Ziviani (2): > > >>> vfio: Set MemoryRegionOps:max_access_size and min_access_size > > >>> vfio: enable 8-byte reads/writes to vfio > > >>> > > >>> hw/vfio/common.c | 14 ++++++++++++++ > > >>> 1 file changed, 14 insertions(+) > > >>> > > >> > > >> I think these patches need to be squashed to be bisectable. > > > > > > No, I think it's fine. The point of patch 1/2 is to indicate that the > > > hardware supports 8-byte accesses, which will still be broken into 2 > > > 4-byte accesses because we don't yet set the implemented width beyond > > > the default. The important part is that the mutex will now group the 4 > > > byte access pair together rather than letting them get re-ordered. > > > Patch 2/2 then implements native 8-byte access. I appreciate them > > > being separate for this subtle nuance, but maybe I'm not seeing the > > > same issue as you. Thanks, > > ' > > I agree, the patches looks fine as is. > > > > Paolo > > > > Hello! > > Thank you all for your review but I have a quick question: is it ok for > merge? :) Yes, I've got it in a local branch, I'll send a pull request this week. Thanks, Alex