[mutter/wip/rstrode/rhel-8.0.0: 17/117] native/gpu: Handle drmModeSetCrtc() failing gracefully

[Ray Strode <halfline src gnome org>]

commit a54976da155f6148d9ee0b500d8401a7acba26ef
Author: Jonas Ådahl <jadahl gmail com>
Date:   Tue Apr 24 09:26:33 2018 +0000

    native/gpu: Handle drmModeSetCrtc() failing gracefully
    
    If drmModeSetCrtc() is called with no fb, mode or connectors for some
    CRTC it may still fail, and we should handle that gracefully instead of
    assuming it failed to set a non-disabled state.
    
    Closes https://gitlab.gnome.org/GNOME/mutter/issues/70
    
    (cherry picked from commit 6e953e2725d5d5b10d14c7bd479bd99f6853addc)

 src/backends/native/meta-gpu-kms.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/src/backends/native/meta-gpu-kms.c b/src/backends/native/meta-gpu-kms.c
index 613a60705..c4a6fb051 100644
--- a/src/backends/native/meta-gpu-kms.c
+++ b/src/backends/native/meta-gpu-kms.c
@@ -143,7 +143,10 @@ meta_gpu_kms_apply_crtc_mode (MetaGpuKms *gpu_kms,
                       connectors, n_connectors,
                       mode) != 0)
     {
-      g_warning ("Failed to set CRTC mode %s: %m", crtc->current_mode->name);
+      if (mode)
+        g_warning ("Failed to set CRTC mode %s: %m", crtc->current_mode->name);
+      else
+        g_warning ("Failed to disable CRTC");
       g_free (connectors);
       return FALSE;
     }