From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33897) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8STj-0005aD-Se for qemu-devel@nongnu.org; Fri, 26 Jun 2015 08:11:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z8STe-0005N9-OB for qemu-devel@nongnu.org; Fri, 26 Jun 2015 08:11:31 -0400 Received: from e06smtp14.uk.ibm.com ([195.75.94.110]:60596) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8STe-0005Mn-Ej for qemu-devel@nongnu.org; Fri, 26 Jun 2015 08:11:26 -0400 Received: from /spool/local by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 26 Jun 2015 13:11:25 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (d06relay10.portsmouth.uk.ibm.com [9.149.109.195]) by d06dlp02.portsmouth.uk.ibm.com (Postfix) with ESMTP id 641D92190066 for ; Fri, 26 Jun 2015 13:11:01 +0100 (BST) Received: from d06av02.portsmouth.uk.ibm.com (d06av02.portsmouth.uk.ibm.com [9.149.37.228]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t5QCBNJB30736410 for ; Fri, 26 Jun 2015 12:11:23 GMT Received: from d06av02.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av02.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t5QCBNnJ021366 for ; Fri, 26 Jun 2015 06:11:23 -0600 Date: Fri, 26 Jun 2015 14:11:12 +0200 From: Greg Kurz Message-ID: <20150626141112.7a92aa82@bahia.local> In-Reply-To: <20150626100045.GJ15457@stefanha-thinkpad.redhat.com> References: <20150625152609.16840.52299.stgit@bahia.lab.toulouse-stg.fr.ibm.com> <20150626100045.GJ15457@stefanha-thinkpad.redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/UM1Jfz7XN+wBXzd1=gjOBRJ"; protocol="application/pgp-signature" Subject: Re: [Qemu-devel] [PATCH] dataplane: drop copy_in_vring_desc() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: Cornelia Huck , qemu-devel@nongnu.org, "Michael S. Tsirkin" --Sig_/UM1Jfz7XN+wBXzd1=gjOBRJ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Fri, 26 Jun 2015 11:00:45 +0100 Stefan Hajnoczi wrote: > On Thu, Jun 25, 2015 at 05:26:09PM +0200, Greg Kurz wrote: > > During early virtio 1.0 devel, there were several proposals about how to > > deal endianness of the vring descriptor fields: > > - convert the decriptor to host endianness in a single place, and use i= ts > > fields directly in the code > > - keep the descriptor untouched and use virtio memory helpers to access= its > > fields with the appropriate endianness > >=20 > > It seems like both approaches got merged: commit f5a5628cf0b6 introduces > > an extra swap that negates the one brought by commit b0e5d90ebc3e. This > > breaks cross-endian setups with the following error: > >=20 > > Failed to map descriptor addr 0x18e2517e00000000 len 268435456 > >=20 > > A solution could be to revert f5a5628cf0b6, but dropping copy_in_vring_= desc() > > is equivalent and gives a smaller patch. >=20 > Cornelia already sent "[PATCH] Revert "dataplane: allow virtio-1 > devices" to revert f5a5628cf0b. I acked it but the patch is going > through Michael Tsirkin. Indeed... my bad, I overlooked that thread... -- G --Sig_/UM1Jfz7XN+wBXzd1=gjOBRJ Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAlWNQWAACgkQAvw66wEB28IGzACdGhz6mR/7tXJJGx98p3fT7ZEC feQAn02pehROhOlw+IIJhBIBDaPjaEVM =Yu+k -----END PGP SIGNATURE----- --Sig_/UM1Jfz7XN+wBXzd1=gjOBRJ--