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Date: Mon, 29 Jun 2026 14:09:30 +0200
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Subject: Re: [PATCH 1/2] drm/sched: Guard sched->ready with ACCESS_ONCE()
To: Philipp Stanner <phasta@kernel.org>
Cc: Matthew Brost <matthew.brost@intel.com>,
 =?UTF-8?Q?Christian_K=C3=B6nig?= <ckoenig.leichtzumerken@gmail.com>,
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 David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>,
 dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
References: <20260629104040.2695163-2-phasta@kernel.org>
From: Danilo Krummrich <dakr@kernel.org>
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> +	WRITE_ONCE(sched->ready, false);

Don't we need smp_store_release() here and

> +	return READ_ONCE(sched->ready);
smp_load_acquire() here?

Also, what about drm_sched_init()? It also seems that this is accessed from
amdgpu without the drm_sched_wqueue_ready() helper about a million times. :)

	$ grep -Rin "sched\.ready" drivers/gpu/drm/amd | wc
	$     119     544   10320

There may be false positives, but from a quick glance at least most of them seem
to actually come from the scheduler.