Re: [PATCH 3/4] drm/i915/contexts: Serialize default context init

[Ben Widawsky <ben@bwidawsk.net>]

On 2012-08-14 00:41, Chris Wilson wrote:
> On Mon, 13 Aug 2012 22:41:10 -0700, Ben Widawsky <ben@bwidawsk.net> 
> wrote:
>> This is possible with the new force paramter in do_switch. As stated 
>> in
>> that patch, the goal is to get a real context stored at the time of
>> initialization.
>>
>> References: https://bugs.freedesktop.org/show_bug.cgi?id=52429
>> Tested-by: Guang A Yang <guang.a.yang@intel.com>
>> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
>
> I'm missing the rationalisation for this pair of patches... For
> instance, I can't see how this closes the hole we have upon resume 
> where
> ring->context_obj == DEFAULT_CONTEXT but CCID is 0.
> -Chris

Yeah this doesn't fix that problem. The problem this is trying to solve 
is suspend/resume before any context switch actually occurs. Basically 
jam the default context obj in, and this allows us to force restore it 
on resume. However, as you point out, I guess that force restore is 
missing. Let me think a bit more/chat on IRC.

-- 
Ben Widawsky, Intel Open Source Technology Center