From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44509) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzrmV-0000zT-A1 for qemu-devel@nongnu.org; Wed, 25 Jun 2014 14:19:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WzrmD-0004eE-6D for qemu-devel@nongnu.org; Wed, 25 Jun 2014 14:18:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55087) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzrmC-0004dn-Sl for qemu-devel@nongnu.org; Wed, 25 Jun 2014 14:18:33 -0400 Date: Wed, 25 Jun 2014 21:18:55 +0300 From: "Michael S. Tsirkin" Message-ID: <20140625181855.GF16636@redhat.com> References: <20140625142704.GC15277@redhat.com> <7B7FFD16-82ED-4D0E-8B83-A6448DC9A344@cisco.com> <20140625152936.GB15720@redhat.com> <20140625155038.GG15720@redhat.com> <7760835F-C1F1-4023-960D-A70096465EBD@cisco.com> <122055914.32517283.1403714698790.JavaMail.zimbra@redhat.com> <20140625180718.GB16636@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] vhost-user: broken mem regions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Nikolay Nikolaev Cc: Paolo Bonzini , "Damjan Marion (damarion)" , qemu-devel On Wed, Jun 25, 2014 at 09:13:36PM +0300, Nikolay Nikolaev wrote: > On Wed, Jun 25, 2014 at 9:07 PM, Michael S. Tsirkin wr= ote: > > On Wed, Jun 25, 2014 at 07:56:46PM +0300, Nikolay Nikolaev wrote: > >> On Wed, Jun 25, 2014 at 7:44 PM, Paolo Bonzini = wrote: > >> >> nregions: 4 > >> >> region: > >> >> gpa =3D 0x100000000 > >> >> size =3D 3221225472 > >> >> ua =3D 0x2aab6ac00000 > >> > > >> > High memory, above 3 gigabytes. > >> > > >> >> region: > >> >> gpa =3D 0xFFFC0000 > >> >> size =3D 262144 > >> >> ua =3D 0x7fc13d200000 > >> > > >> > This is the BIOS. There shouldn't be any FD for this one, it > >> > is not allocated in hugetlbfs. > >> > > >> >> region: > >> >> gpa =3D 0x0 > >> >> size =3D 655360 > >> >> ua =3D 0x2aaaaac00000 > >> >> region: > >> >> gpa =3D 0xC0000 > >> >> size =3D 3220439040 > >> >> ua =3D 0x2aaaaacc0000 > >> > > >> > Together, it's the first 3 GB of memory. > >> > > >> > I understand now what you mean. Yeah, the format should be change= d > >> > to include the offset (why does vhost-user need the ua at all? > >> The vring addresses are QEMU UA addresses. Of course vhost-user can > >> translate them to guest physical before sending the message. > > > > It seems useful to have them as QEMU UA, this will allow > > frontends other than virtio where QEMU operates the > > ring. >=20 > OK - so there will be a new offset field. That's fine with me. What > would be the deadline for such change? > It's not exactly bugfix. On the other hand there's no wide adoption of > the protocol so it's still not critical to change it. Right. So you have to do this before the hard freeze. And don't cut it too fine either :) > > > >> > perhaps the offset can replace the ua). > >> > > >> >> BTW Any idea what to do with region 2, it doesn=E2=80=99t look li= ke the one belonging > >> >> to the same place, but qemu_get_ram_fd() returns same FD for it. > >> > > >> > This must be a bug. I would have expected qemu_get_ram_fd to retu= rn -1 > >> > here, so no descriptor should be passed to vhost-user. > >> > > >> > Paolo