On Mon, May 25, 2026 at 08:19:56AM +0200, Walter Alejandro Iglesias wrote:
> Does your machine have an intel gpu?
> 
> When you run zzz or ZZZ from wscons, do you experience "ghosting" after
> resuming?
> 
> By ghosting I mean the same valid output that was there before suspend
> or hibernate but partially printed again, overlapping valid output, in
> the form of characters scattered here and there or black squares which
> size can vary from 4x4 characters to half screen.  And when you switch
> to and back from another virtual terminal[1] (Ctrl+Alt+F?) all that
> ghost goes away.
> 
> If that's also your case, try the diff below please.  Your feedback will
> be useful.  (Include dmesg to let developers know your hardware.)
> 
> [1] This last test is important, since in some cases the ghosting can
>     be subtle and go unnoticed.  Also, try with different contents in
>     the console before zzz or ZZZ, like the output of 'cal -y' which
>     is easily recognizable.
> 
> 

Sorry for breaking your thread, but I have the same problem with wscons
screen burner on my GEMINILAKE. The following diff fixes it to me. I'm
not very close to DRM, so this could be not the right place.

I also have the problem with wscons screen burner on ALDERLAKE. I don't
know how describe it, so the screeshot [1]. After screen unblan, the
output happens only in upper left corner, the upper half of the first
line. The other screen contains garbage.

The diff below doesn't fixes the problem, but at least I see no garbage
on the screen.

1. https://ibb.co/DHWcWNx5

Index: sys/dev/pci/drm/i915/i915_driver.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/drm/i915/i915_driver.c,v
retrieving revision 1.30
diff -u -p -r1.30 i915_driver.c
--- sys/dev/pci/drm/i915/i915_driver.c	30 Apr 2026 04:33:06 -0000	1.30
+++ sys/dev/pci/drm/i915/i915_driver.c	25 May 2026 18:53:02 -0000
@@ -2154,8 +2154,10 @@ inteldrm_burner_cb(void *arg1)
 	struct drm_i915_private *dev_priv = arg1;
 	struct drm_device *dev = &dev_priv->drm;
 	struct drm_fb_helper *helper = dev->fb_helper;
+	struct rasops_info *ri = &dev_priv->ro;
 
 	drm_fb_helper_blank(dev_priv->burner_fblank, helper->info);
+	rasops_show_screen(ri, ri->ri_active, 0, NULL, NULL);
 }
 
 int