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Date: Mon, 9 Feb 2026 18:04:15 -0500
From: Hamza Mahfooz <someguy@effective-light.com>
To: Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig@amd.com>
Cc: dri-devel@lists.freedesktop.org,
	Timur =?iso-8859-1?Q?Krist=F3f?= <timur.kristof@gmail.com>,
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	Xaver Hugl <xaver.hugl@kde.org>,
	Harry Wentland <harry.wentland@amd.com>,
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	Fangzhi Zuo <Jerry.Zuo@amd.com>, amd-gfx@lists.freedesktop.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] drm: introduce KMS recovery mechanism
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 <2ac2dc2f-552c-4084-872b-179a1e489156@amd.com>
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On Mon, Feb 09, 2026 at 10:35:05AM +0100, Christian König wrote:
> > +	/**
> > +	 * @page_flip_timeout:
> > +	 *
> > +	 * This optional hook is called if &drm_crtc_commit.flip_done times out,
> > +	 * and can be used by drivers to attempt to recover from a page flip
> > +	 * timeout.
> > +	 */
> > +	void (*page_flip_timeout)(struct drm_crtc *crtc);
> 
> As far as I can see a callback is clearly not the right approach.
> 
> The drm_atomic_helper_wait_for_flip_done() helper is called by the driver, isn't it?
> 
> So what we need is just to give an error code back to the driver.
> 

I guess we could just have the function return -ETIMEOUT, but then
drivers wouldn't know which crtc is timing out and AFAIK drivers aren't
supposed to touch `drm_crtc_commit`s so they don't really have a
sanctioned means to figure that out on their own.