[Intel-gfx] [PATCH i-g-t 2/2] lib/igt_kms: Disable crtc in legacy path when output is unset

[Mika Kahola]

On Tue, 2017-10-03 at 16:11 +0200, Maarten Lankhorst wrote:
> When the output is unset, but the fb is still valid we still have
> to perform a disable on the crtc.
> 
> This ixes the following crash in kms_color (although previous commit
> does as well):
> 
> (gdb) bt
> 0  igt_output_get_mode (output=output at entry=0x0) at igt_kms.c:2828
> 1  0x000055555556f0d5 in igt_primary_plane_commit_legacy(..) at
> igt_kms.c:2341
> 2  igt_plane_commit (fail_on_error=true, s=COMMIT_LEGACY, ..) at
> igt_kms.c:2394
> 3  igt_pipe_commit (fail_on_error=true, s=COMMIT_LEGACY, ..) at
> igt_kms.c:2435
> 4  do_display_commit (display=0x7fffffffe5d8, s=COMMIT_LEGACY, ..) at
> igt_kms.c:2667
> 5  0x000055555556f38e in igt_display_commit2 (display=<optimized
> out>, s=<optimized out>) at igt_kms.c:2777
> 6  0x000055555555ef84 in run_tests_for_pipe (data=.., p=PIPE_B) at
> kms_color.c:1053
> 7  0x000055555555f610 in __real_main1189 () at kms_color.c:1206
> 8  0x000055555555cbc7 in main (argc=<optimized out>, argv=<optimized
> out>) at kms_color.c:1189
> 
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Reviewed-by: Mika Kahola <mika.kahola at intel.com>

> ---
>  lib/igt_kms.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index d25090b05c70..a572fc60d59d 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -2336,7 +2336,7 @@ static int
> igt_primary_plane_commit_legacy(igt_plane_t *primary,
>  		return 0;
>  
>  	crtc_id = pipe->crtc_id;
> -	fb_id = igt_plane_get_fb_id(primary);
> +	fb_id = output ? igt_plane_get_fb_id(primary) : 0;
>  	if (fb_id)
>  		mode = igt_output_get_mode(output);
>  	else