From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f180.google.com ([209.85.212.180]:33903 "EHLO mail-wi0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751588AbbG3Owi (ORCPT ); Thu, 30 Jul 2015 10:52:38 -0400 Received: by wibud3 with SMTP id ud3so24471039wib.1 for ; Thu, 30 Jul 2015 07:52:37 -0700 (PDT) Date: Thu, 30 Jul 2015 16:52:33 +0200 From: Daniel Vetter To: Chris Wilson , intel-gfx@lists.freedesktop.org, Daniel Vetter , stable@vger.kernel.org Subject: Re: [PATCH] drm/i915: Declare the swizzling unknown for L-shaped configurations Message-ID: <20150730145233.GA16722@phenom.ffwll.local> References: <1435479566-25065-1-git-send-email-chris@chris-wilson.co.uk> <20150730070507.GG6035@nuc-i3427.alporthouse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150730070507.GG6035@nuc-i3427.alporthouse.com> Sender: stable-owner@vger.kernel.org List-ID: On Thu, Jul 30, 2015 at 08:05:07AM +0100, Chris Wilson wrote: > On Sun, Jun 28, 2015 at 09:19:26AM +0100, Chris Wilson wrote: > > The old style of memory interleaving swizzled upto the end of the > > first even bank of memory, and then used the remainder as unswizzled on > > the unpaired bank - i.e. swizzling is not constant for all memory. This > > causes problems when we try to migrate memory and so the kernel prevents > > migration at all when we detect L-shaped inconsistent swizzling. > > However, this issue also extends to userspace who try to manually detile > > into memory as the swizzling for an individual page is unknown (it > > depends on its physical address only known to the kernel), userspace > > cannot correctly swizzle. > > > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91105 > > Signed-off-by: Chris Wilson > > Cc: Daniel Vetter > > Cc: stable@vger.kernel.org > > Daniel since you dropped v2 and had already reviewed this version, it > would have been useful had you done the swap... Simply forgot, sorry. I added a note about the earlier attempt and also one to explain that cc: stable is for fixing up wc mmaps. Picked up for -fixes, thanks for the patch. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch