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Date:   Thu, 23 Jun 2022 13:17:30 +0200
From:   Andi Shyti <andi.shyti@linux.intel.com>
To:     Mauro Carvalho Chehab <mchehab@kernel.org>
Cc:     Chris Wilson <chris.p.wilson@intel.com>,
        Fei Yang <fei.yang@intel.com>,
        Thomas Hellstrom <thomas.hellstrom@intel.com>,
        Bruce Chang <yu.bruce.chang@intel.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Dave Airlie <airlied@redhat.com>,
        David Airlie <airlied@linux.ie>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        John Harrison <John.C.Harrison@intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Matt Roper <matthew.d.roper@intel.com>,
        Matthew Brost <matthew.brost@intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com>,
        Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
        Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>,
        dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, mauro.chehab@linux.intel.com,
        Mika Kuoppala <mika.kuoppala@linux.intel.com>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        stable@vger.kernel.org,
        Thomas =?iso-8859-15?Q?Hellstr=F6m?= 
        <thomas.hellstrom@linux.intel.com>
Subject: Re: [PATCH 5/6] drm/i915/gt: Serialize GRDOM access between multiple
 engine resets
Message-ID: <YrRLyg1IJoZpVGfg@intel.intel>
References: <cover.1655306128.git.mchehab@kernel.org>
 <5ee647f243a774927ec328bfca8212abc4957909.1655306128.git.mchehab@kernel.org>
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Hi Mauro,

On Wed, Jun 15, 2022 at 04:27:39PM +0100, Mauro Carvalho Chehab wrote:
> From: Chris Wilson <chris.p.wilson@intel.com>
> 
> Don't allow two engines to be reset in parallel, as they would both
> try to select a reset bit (and send requests to common registers)
> and wait on that register, at the same time. Serialize control of
> the reset requests/acks using the uncore->lock, which will also ensure
> that no other GT state changes at the same time as the actual reset.
> 
> Fixes: 7938d61591d3 ("drm/i915: Flush TLBs before releasing backing store")
> 
> Reported-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
> Cc: Andi Shyti <andi.shyti@intel.com>
> Cc: stable@vger.kernel.org
> Acked-by: Thomas Hellstr?m <thomas.hellstrom@linux.intel.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

Thanks,
Andi