[Mesa-dev] [PATCH 2/2] drisw: Use separate drisw_loader_funcs for shm

[Emil Velikov]

Hi Michal,

On 2018/11/23, Michal Srb wrote:
> The original code was modifying the global drisw_lf variable, which is bad
> when there are multiple contexts in single process, each initialized with
> different loader. One may support put_image_shm and the other not.
> 
> Since there are currently only two possible combinations, lets create two
> global tables, one for each. Lets make them const, since we won't change them
> and they can be shared.
> 
When possible, please mention the commit which "breaks" things, like
below. It helps highlight exactly where a backport/cherry-pick is
applicable.

Fixes: 63c427fa71a ("drisw: use putImageShm if available")

> Signed-off-by: Michal Srb <msrb at suse.com>
> ---
> This fixes crash in VLC. It used two GL contexts (each in different thread), one
> was initialized by its Qt GUI, the other by its video output plugin. The first
> one set the put_image_shm=drisw_put_image_shm, the second did not, but
> since the same structure was used, the drisw_put_image_shm was used too. Then
> it crashed because the second loader did not have putImageShm set.
> 
> Downstream bug:
> https://bugzilla.opensuse.org/show_bug.cgi?id=1113533
> 
Personally, I'd keep the extra note about VLC and downstream bug in the
commit message. Although if you prefer let's keep it as-is.

For the series:
Reviewed-by: Emil Velikov <emil.velikov at collabora.com>

I'll push this early/mid next weeks, unless someone beats me to it.

Thanks
Emil