From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Wondering about cirris and stdvga Date: Fri, 18 Nov 2016 19:04:15 +0100 Message-ID: <1479492255.3832.52.camel@citrix.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1955171946076683883==" Return-path: Received: from mail6.bemta6.messagelabs.com ([193.109.254.103]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c7nWR-0000nV-Gf for xen-devel@lists.xenproject.org; Fri, 18 Nov 2016 18:04:23 +0000 List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" To: Konrad Rzeszutek Wilk , Paul Durrant Cc: "anthony.perard" , xen-devel , Stefano Stabellini , Ian Jackson , Roger Pau Monne List-Id: xen-devel@lists.xenproject.org --===============1955171946076683883== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="=-742CU0/4J3I4lirhyDGZ" --=-742CU0/4J3I4lirhyDGZ Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sending again, this time, with Anthony's and xen-devel address spelled right. Sorry!! :-( ------------------------------------------- Hello to you, various pseudo-random people, It's not my field of expertise, so bear with me, at least a little bit (and, Konrad, you help me, or there will be consequences! :-D) So, I and Konrad recently discovered --while testing the about to be released Fedora 25 as a Xen guest-- that the Cirrus emulated graphic card that we consume from QEMU for HVM guests is broken on Wayland. We just discovered it because Fedora 25 uses Wayland by default, but it appears not to be something new: https://bugzilla.redhat.com/show_bug.cgi?id=3D1227770 And at least from what we see in that bugreport, not much has happened so far. Using "vga=3D'stdvga'" in the config file, or even "vga=3D'qxl'" make things work again. Disabling Wayland in the guest also works (i.e., if not using Wayland, Cirrus is ok). And that's what made us think that it's probably a Wayland issue. I've tried the same on KVM, and the situation is identical (Cirrus+Wayland=3Dbreaks, whatever-else+Wayland=3Dworks, Cirrus+Xorg=3Dworks). I've also read around that these days, e.g., stdvga is at least as good as cirrus, performance wise, that cirrus is broken and impossible to fix (because it is the hardware that it's emulating that was broken), that stdvga enables better screen resolution in guests, etc. I'm not sure about these claims, in particular the performance one, is probably pretty hard to verify. And as I said, it's not my field. Still I thought it could be worthwhile to at least bring this up: should we start to consider changing the default from cirrus to stdvga (or something else)? Thanks for your time and Regards, Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-742CU0/4J3I4lirhyDGZ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABCAAGBQJYL0KfAAoJEBZCeImluHPuYEIP/3nRyhVqBXj44MCppMPyjGCd kUe3E7U/rthpeoqmAZhdmfRbWNZK+MJo8m9QTCs4ukMK7EB3VTrDvu27NVinihUq 8LStGEW8y6EWRAY9D9O8+6qEqyDeuMr7cYVxAotaoNdi0zCXXPF+RPeQ5QXc0aX+ 6lNLxrcQnrITHfZyVm0g386f8ZGneKz9I9FBpgXn8rHX0i/Fx+AprpldGBkCsvBV jV0Om6fpOB3qQ+gi8tee3/p+sJ8SXK94xyv0eRoYkMwIJguZj0bypgACyAcZb8mi ROAa0BSuYTb2VqeXoz6o9bCDVXFhrYAYvp0xqNQ2veEvWVslKkQ1iqCCPAk5lzQg 4GRbQ96ruJwPR7doBB7nM6pYL6v/Mu0bbgd2NoNHo2M3F4tgGyVUOe0QmCf+HCkR bbs3aghrqyRm25ye+GNzIDH9GJmPcYpmfioZhc4bCWX9qt9RKsvJ6uX9T1KzopjA iXQ07OmiTWQA4bPPa/4Gd4ynVpQL+S53HqAlmfBgFV94OZKhePUSTMXkqFD33E7G 2NNIwfq1NA7U35lLKCkQ+llvhGXf5Byn9SqKhHQY904HNVwqw4vFSmtQ3npqR8CD 3lN0YUTKYcigS0qfRwkVYORXEEwTsQ5v1sDbHLeKDu9/euqs26ck5Tu0vZ5/y0mo uKWlnK/sK0tUwVcHV205 =KiJP -----END PGP SIGNATURE----- --=-742CU0/4J3I4lirhyDGZ-- --===============1955171946076683883== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KWGVuLWRldmVs IG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVuLm9yZwpodHRwczovL2xpc3RzLnhlbi5v cmcveGVuLWRldmVsCg== --===============1955171946076683883==--