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Date: Thu, 12 Jan 2023 08:56:57 -0700
From: Nathan Chancellor <nathan@kernel.org>
To: Jocelyn Falempe <jfalempe@redhat.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>,
	Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
	Rodrigo Vivi <rodrigo.vivi@intel.com>,
	Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
	Kees Cook <keescook@chromium.org>, Tom Rix <trix@redhat.com>,
	intel-gfx@lists.freedesktop.org, llvm@lists.linux.dev,
	Nick Desaulniers <ndesaulniers@google.com>, patches@lists.linux.dev,
	dri-devel@lists.freedesktop.org,
	Andrzej Hajda <andrzej.hajda@intel.com>,
	Sami Tolvanen <samitolvanen@google.com>,
	Andi Shyti <andi.shyti@linux.intel.com>
Subject: Re: [PATCH v2] drm/i915: Fix CFI violations in gt_sysfs
Message-ID: <Y8Atycuni0bl8std@dev-arch.thelio-3990X>
References: <20221013205909.1282545-1-nathan@kernel.org>
 <4dcf830e-62a5-837b-7590-ac5395f84c14@redhat.com>
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In-Reply-To: <4dcf830e-62a5-837b-7590-ac5395f84c14@redhat.com>

Hi Jocelyn,

On Thu, Jan 12, 2023 at 11:08:17AM +0100, Jocelyn Falempe wrote:
> This patch does also solve a kernel crash when reading
> /sys/class/drm/card1/gt/gt0/* on a skylake machine:
> https://bugzilla.redhat.com/show_bug.cgi?id=2154880

Interesting, I wonder what aspect of this patch fixes this because I am
not sure that is an intended consequence of this change but that is
still good to hear!

For the record, this is commit a8a4f0467d70 ("drm/i915: Fix CFI
violations in gt_sysfs") in mainline.

> Do you think it can be backported to stable releases ?
> Conflicts are trivial on top of v6.0 at least.

I had a report from another user of this crash affecting them with kCFI
so it is on my TODO to backport it to 6.1 (6.0 just went EOL) but I am
currently out of the office until next Wednesday so I won't be able to
get to it until then (as I would like to test the backport on affected
hardware). If someone wants to beat me to it, I won't complain ;)

Cheers,
Nathan