Hi Arnd, Thanks for your patch. It would be good to improve the patch's head line to something like: drm/imx: imx-ldb: fix out of bounds array access warning Regards, Liu Ying On Tue, 2021-03-23 at 14:05 +0100, Arnd Bergmann wrote: > From: Arnd Bergmann <arnd@xxxxxxxx> > > When CONFIG_OF is disabled, building with 'make W=1' produces warnings > about out of bounds array access: > > drivers/gpu/drm/imx/imx-ldb.c: In function 'imx_ldb_set_clock.constprop': > drivers/gpu/drm/imx/imx-ldb.c:186:8: error: array subscript -22 is below array bounds of 'struct clk *[4]' [-Werror=array-bounds] > > Add an error check before the index is used, which helps with the > warning, as well as any possible other error condition that may be > triggered at runtime. > > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> > --- > drivers/gpu/drm/imx/imx-ldb.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c > index dbfe39e2f7f6..1210360cec8a 100644 > --- a/drivers/gpu/drm/imx/imx-ldb.c > +++ b/drivers/gpu/drm/imx/imx-ldb.c > @@ -197,6 +197,12 @@ static void imx_ldb_encoder_enable(struct drm_encoder *encoder) > int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN; > int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder); > > + if (mux < 0) { > + dev_warn(ldb->dev, > + "%s: invalid mux\n", __func__); > + return; > + } > + > drm_panel_prepare(imx_ldb_ch->panel); > > if (dual) { > @@ -255,6 +261,12 @@ imx_ldb_encoder_atomic_mode_set(struct drm_encoder *encoder, > int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder); > u32 bus_format = imx_ldb_ch->bus_format; > > + if (mux < 0) { > + dev_warn(ldb->dev, > + "%s: invalid mux\n", __func__); > + return; > + } > + > if (mode->clock > 170000) { > dev_warn(ldb->dev, > "%s: mode exceeds 170 MHz pixel clock\n", __func__); _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel