| Message ID | 20181002215917.1849-1-giulio.benetti@micronovasrl.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] drm/sun4i: tcon: fix check of tcon->panel null pointer | expand |
Sorry for sending twice(and top posting), but I was not subscribed to dri-devel ML, so patchwork was not aware of these 2 patches. Best regards
On Wed, Oct 3, 2018 at 5:59 AM Giulio Benetti <giulio.benetti@micronovasrl.com> wrote: > > At the moment, the check of tcon->panel to be valid is wrong. IS_ERR() > has been used, but that macro doesn't check if tcon->panel pointer is > null or not, but check if tcon->panel is between -1 and -4095(MAX_ERRNO). > > Remove IS_ERR() from tcon->panel checking and let "if (tcon->panel)" as > condition to check if it's a pointer not null. There's actually more than one occurance of this error: drivers/gpu/drm/sun4i/sun4i_lvds.c: if (!IS_ERR(tcon->panel)) { drivers/gpu/drm/sun4i/sun4i_lvds.c: if (!IS_ERR(tcon->panel)) { drivers/gpu/drm/sun4i/sun4i_rgb.c: if (!IS_ERR(tcon->panel)) { drivers/gpu/drm/sun4i/sun4i_rgb.c: if (!IS_ERR(tcon->panel)) { These four are responsible for enabling and disabling the panel. drivers/gpu/drm/sun4i/sun4i_tcon.c: if (!IS_ERR(tcon->panel)) { All this looks like it was left over from commit ebc9446135671 ("drm: convert drivers to use drm_of_find_panel_or_bridge"). We have checks against tcon->panel in several places and not all of them were converted. ChenYu > Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com> > --- > drivers/gpu/drm/sun4i/sun4i_tcon.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c > index c78cd35a1294..e4b3bd0307ef 100644 > --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c > +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c > @@ -555,7 +555,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, > * Following code is a way to avoid quirks all around TCON > * and DOTCLOCK drivers. > */ > - if (!IS_ERR(tcon->panel)) { > + if (tcon->panel) { > struct drm_panel *panel = tcon->panel; > struct drm_connector *connector = panel->connector; > struct drm_display_info display_info = connector->display_info; > -- > 2.17.1 >
Il 03/10/2018 11:43, Chen-Yu Tsai ha scritto: > On Wed, Oct 3, 2018 at 5:59 AM Giulio Benetti > <giulio.benetti@micronovasrl.com> wrote: >> >> At the moment, the check of tcon->panel to be valid is wrong. IS_ERR() >> has been used, but that macro doesn't check if tcon->panel pointer is >> null or not, but check if tcon->panel is between -1 and -4095(MAX_ERRNO). >> >> Remove IS_ERR() from tcon->panel checking and let "if (tcon->panel)" as >> condition to check if it's a pointer not null. > > There's actually more than one occurance of this error: > > drivers/gpu/drm/sun4i/sun4i_lvds.c: if (!IS_ERR(tcon->panel)) { > drivers/gpu/drm/sun4i/sun4i_lvds.c: if (!IS_ERR(tcon->panel)) { > drivers/gpu/drm/sun4i/sun4i_rgb.c: if (!IS_ERR(tcon->panel)) { > drivers/gpu/drm/sun4i/sun4i_rgb.c: if (!IS_ERR(tcon->panel)) { > > These four are responsible for enabling and disabling the panel. > > drivers/gpu/drm/sun4i/sun4i_tcon.c: if (!IS_ERR(tcon->panel)) { > > All this looks like it was left over from commit ebc9446135671 ("drm: convert > drivers to use drm_of_find_panel_or_bridge"). We have checks against tcon->panel > in several places and not all of them were converted. > Then, I'm going to send a patchset to correct them. Best regards
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c index c78cd35a1294..e4b3bd0307ef 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -555,7 +555,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, * Following code is a way to avoid quirks all around TCON * and DOTCLOCK drivers. */ - if (!IS_ERR(tcon->panel)) { + if (tcon->panel) { struct drm_panel *panel = tcon->panel; struct drm_connector *connector = panel->connector; struct drm_display_info display_info = connector->display_info;
At the moment, the check of tcon->panel to be valid is wrong. IS_ERR() has been used, but that macro doesn't check if tcon->panel pointer is null or not, but check if tcon->panel is between -1 and -4095(MAX_ERRNO). Remove IS_ERR() from tcon->panel checking and let "if (tcon->panel)" as condition to check if it's a pointer not null. Signed-off-by: Giulio Benetti <giulio.benetti@micronovasrl.com> --- drivers/gpu/drm/sun4i/sun4i_tcon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)