From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44575) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f49O2-00071r-HU for qemu-devel@nongnu.org; Thu, 05 Apr 2018 14:13:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f49Nz-00048T-6O for qemu-devel@nongnu.org; Thu, 05 Apr 2018 14:13:26 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:50540 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f49Nz-00047w-2N for qemu-devel@nongnu.org; Thu, 05 Apr 2018 14:13:23 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E6F1B8182D0C for ; Thu, 5 Apr 2018 18:13:16 +0000 (UTC) Date: Thu, 5 Apr 2018 12:13:13 -0600 From: Alex Williamson Message-ID: <20180405121313.3bf29ca8@w520.home> In-Reply-To: <20180323153939.16684-1-dgilbert@redhat.com> References: <20180323153939.16684-1-dgilbert@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] vhost: Allow adjoining regions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert (git)" Cc: qemu-devel@nongnu.org, mst@redhat.com On Fri, 23 Mar 2018 15:39:39 +0000 "Dr. David Alan Gilbert (git)" wrote: > From: "Dr. David Alan Gilbert" > > My rework of section adding combines overlapping or adjoining regions, > but checks they're actually the same underlying RAM block. > Fix the case where two blocks adjoin but don't overlap; that new region > should get added (but not combined), but my previous patch was disallowing it. > > Fixes: c1ece84e7c9 > > Reported-by: Alex Williamson > Signed-off-by: Dr. David Alan Gilbert > --- Ping? This error report is a regression and should be considered for 2.12. Tested-by: Alex Williamson > hw/virtio/vhost.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > index 250f886acb..2a720cca3d 100644 > --- a/hw/virtio/vhost.c > +++ b/hw/virtio/vhost.c > @@ -595,10 +595,15 @@ static void vhost_region_add_section(struct vhost_dev *dev, > prev_sec->offset_within_address_space, > prev_sec->offset_within_region); > } else { > - error_report("%s: Overlapping but not coherent sections " > - "at %"PRIx64, > - __func__, mrs_gpa); > - return; > + /* adjoining regions are fine, but overlapping ones with > + * different blocks/offsets shouldn't happen > + */ > + if (mrs_gpa != prev_gpa_end + 1) { > + error_report("%s: Overlapping but not coherent sections " > + "at %"PRIx64, > + __func__, mrs_gpa); > + return; > + } > } > } > }