From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesse Barnes <jbarnes@virtuousgeek.org>
Subject: Re: [PATCH] drm/i915: Kill dangerous pending-flip
	debugging
Date: Sat, 15 May 2010 09:31:17 -0700
Message-ID: <20100515093117.254dfb1b@blake>
References: <1273913823-29591-1-git-send-email-chris@chris-wilson.co.uk>
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To: Chris Wilson <chris@chris-wilson.co.uk>
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On Sat, 15 May 2010 09:57:03 +0100
Chris Wilson <chris@chris-wilson.co.uk> wrote:

> We can, by virtue of a vblank interrupt firing in the middle of
> setting up the unpin work (i.e. after we set the unpin_work field and
> before we write to the ringbuffer) enter intel_finish_page_flip()
> prior to receiving the pending flip notification. Therefore we can
> expect to hit intel_finish_page_flip() under normal circumstances
> without a pending flip and even without installing the
> pending_flip_obj. This is exacerbated by aperture thrashing whilst
> binding the framebuffer
> 
> References:
> 
>   Bug 28079 - "glresize" causes kernel panic in
> intel_finish_page_flip.
> https://bugs.freedesktop.org/show_bug.cgi?id=28079

Yeah, that's true.  Good catch.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>