[Mesa-dev] [PATCH] gallium: Correctly handle no config context creation

[Elie Tournier]

This patch fixes the following Piglit test:
spec at egl_mesa_configless_context@basic
It also fixes few test in a virgl guest.

Suggested-by: Emil Velikov <emil.velikov at collabora.com>
Signed-off-by: Elie Tournier <elie.tournier at collabora.com>
---
I cc'ed some Gallium driver people.
Can you check if this patch doesn't introduce any bug on your HW?
Sorry for the spam.
Cheers.
 src/gallium/include/state_tracker/st_api.h  | 2 ++
 src/gallium/state_trackers/dri/dri_screen.c | 4 +++-
 src/mesa/state_tracker/st_manager.c         | 9 ++++++++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/gallium/include/state_tracker/st_api.h b/src/gallium/include/state_tracker/st_api.h
index 61152e3546..2b63b8a3d2 100644
--- a/src/gallium/include/state_tracker/st_api.h
+++ b/src/gallium/include/state_tracker/st_api.h
@@ -190,6 +190,8 @@ struct st_egl_image
  */
 struct st_visual
 {
+   bool no_config;
+
    /**
     * Available buffers.  Bitfield of ST_ATTACHMENT_*_MASK bits.
     */
diff --git a/src/gallium/state_trackers/dri/dri_screen.c b/src/gallium/state_trackers/dri/dri_screen.c
index 027e85024f..308e23685e 100644
--- a/src/gallium/state_trackers/dri/dri_screen.c
+++ b/src/gallium/state_trackers/dri/dri_screen.c
@@ -308,8 +308,10 @@ dri_fill_st_visual(struct st_visual *stvis,
 {
    memset(stvis, 0, sizeof(*stvis));
 
-   if (!mode)
+   if (!mode) {
+      stvis->no_config = true;
       return;
+   }
 
    /* Deduce the color format. */
    switch (mode->redMask) {
diff --git a/src/mesa/state_tracker/st_manager.c b/src/mesa/state_tracker/st_manager.c
index 69286b5791..c1e647b30e 100644
--- a/src/mesa/state_tracker/st_manager.c
+++ b/src/mesa/state_tracker/st_manager.c
@@ -834,6 +834,7 @@ st_api_create_context(struct st_api *stapi, struct st_manager *smapi,
    struct st_context *shared_ctx = (struct st_context *) shared_stctxi;
    struct st_context *st;
    struct pipe_context *pipe;
+   struct gl_config* mode_ptr;
    struct gl_config mode;
    gl_api api;
    bool no_error = false;
@@ -893,7 +894,13 @@ st_api_create_context(struct st_api *stapi, struct st_manager *smapi,
    }
 
    st_visual_to_context_mode(&attribs->visual, &mode);
-   st = st_create_context(api, pipe, &mode, shared_ctx,
+
+   if (&attribs->visual.no_config)
+      mode_ptr = NULL;
+   else
+      mode_ptr = &mode;
+
+   st = st_create_context(api, pipe, mode_ptr, shared_ctx,
                           &attribs->options, no_error);
    if (!st) {
       *error = ST_CONTEXT_ERROR_NO_MEMORY;
-- 
2.18.0