[PATCH 2/4] winex11: move XDestroyWindow() after free_gl_drawable() in set_win_format()

[Miklós Máté]

On 04/04/17 16:06, Alexandre Julliard wrote:
> Miklós Máté <mtmkls at gmail.com> writes:
>
>> On 04/04/17 12:11, Alexandre Julliard wrote:
>>> Miklós Máté <mtmkls at gmail.com> writes:
>>>
>>>> @@ -1334,21 +1334,21 @@ static void free_gl_drawable( struct gl_drawable *gl )
>>>>    /***********************************************************************
>>>>     *              create_gl_drawable
>>>>     */
>>>> -static BOOL create_gl_drawable( HWND hwnd, struct gl_drawable *gl )
>>>> +static BOOL create_gl_drawable( HWND hwnd, struct gl_drawable *gl, struct x11drv_win_data *data )
>>>>    {
>>>>        gl->drawable = 0;
>>>>          if (GetAncestor( hwnd, GA_PARENT ) == GetDesktopWindow())
>>>> /* top-level window */
>>>>        {
>>>> -        struct x11drv_win_data *data = get_win_data( hwnd );
>>>> -
>>>>            if (data)
>>>>            {
>>>>                gl->type = DC_GL_WINDOW;
>>>>                gl->window = create_client_window( data, gl->visual );
>>>>                if (gl->window)
>>>> +            {
>>>>                    gl->drawable = pglXCreateWindow( gdi_display, gl->format->fbconfig, gl->window, NULL );
>>>> -            release_win_data( data );
>>>> +                XSync( gdi_display, False );
>>> Do you really need all the extra XSync calls?  We try to avoid server
>>> round-trips as much as possible.
>>>
>> Yes. We must ensure that glXCreateWindow() and glXDestroyWindow()
>> refer to a valid X window, so the command queue of data->display and
>> gdi_display have to be in sync around those calls.
> If the goal is that the X window is valid, I'd have expected an XSync on
> the thread display. Why is the XSync on gdi_display needed here? What is
> the scenario that fails?
>
> I'm not questioning that some XSyncs are necessary (and we already have
> a few), but I want to make sure we don't add more than needed.
>
This one prevents crash in the following scenario:

1. create_gl_drawable()

2. X11DRV_ThreadDetach() calls XCloseDisplay( data->display );

3. the Xserver processes the glXCreateWindow in the command queue of 
gdi_display -> X window is not valid

This happens sometimes during the ddraw and d3d9 tests.

MM