[PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'

[Dan Carpenter]

On Mon, Mar 09, 2020 at 08:24:04AM +0000, Walter Harms wrote:
> 
> ________________________________________
> Von: kernel-janitors-owner at vger.kernel.org <kernel-janitors-owner at vger.kernel.org> im Auftrag von Christophe JAILLET <christophe.jaillet at wanadoo.fr>
> Gesendet: Sonntag, 8. März 2020 10:26
> An: harry.wentland at amd.com; sunpeng.li at amd.com; alexander.deucher at amd.com; christian.koenig at amd.com; David1.Zhou at amd.com; airlied at linux.ie; daniel at ffwll.ch; nicholas.kazlauskas at amd.com; Bhawanpreet.Lakha at amd.com; mario.kleiner.de at gmail.com; David.Francis at amd.com
> Cc: amd-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org; linux-kernel at vger.kernel.org; kernel-janitors at vger.kernel.org; Christophe JAILLET
> Betreff: [PATCH] drm/amdgpu/display: Fix an error handling path in 'dm_update_crtc_state()'
> 
> 'dc_stream_release()' may be called twice. Once here, and once below in the
> error handling path if we branch to the 'fail' label.
> 
> Set 'new_stream' to NULL, once released to avoid the duplicated release
> function call.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet at wanadoo.fr>
> ---
> Maybe the 'goto fail' at line 7745 should be turned into a 'return ret'
> instead. Could be clearer.
> 
> No Fixes tag provided because I've not been able to dig deep enough in the
> git history.
> ---
>  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 97c1b01c0fc1..9d7773a77c4f 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -7704,8 +7704,10 @@ static int dm_update_crtc_state(struct amdgpu_display_manager *dm,
> 
>  skip_modeset:
>         /* Release extra reference */
> -       if (new_stream)
> -                dc_stream_release(new_stream);
> +       if (new_stream) {
> +               dc_stream_release(new_stream);
> +               new_stream = NULL;
> +       }
> 
> 
> dc_stream_release() is NULL-checked, so the if can be dropped.
> 
> re,
>  wh

Walter, it's really hard to separate your reply from the quoted email.
What's going on with that?  Could you configure your email client to
use "> " for the quoted bit?

regards,
dan carpenter