| Message ID | 20220624013159.88646-1-jiapeng.chong@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/ingenic: Use resource_size function on resource object | expand |
Hi Jiapeng, On Fri, Jun 24, 2022 at 09:31:59AM +0800, Jiapeng Chong wrote: > This was found by coccicheck: > > ./drivers/gpu/drm/ingenic/ingenic-drm-drv.c:1149:35-38: WARNING: Suspicious code. resource_size is maybe missing with res. > Nice one, now I have to go back and fix my code as well. > Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Hi, Le ven., juin 24 2022 at 09:31:59 +0800, Jiapeng Chong <jiapeng.chong@linux.alibaba.com> a écrit : > This was found by coccicheck: > > ./drivers/gpu/drm/ingenic/ingenic-drm-drv.c:1149:35-38: WARNING: > Suspicious code. resource_size is maybe missing with res. > > Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> > --- > drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > index 2c559885347a..5514b163999f 100644 > --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > @@ -1146,7 +1146,7 @@ static int ingenic_drm_bind(struct device *dev, > bool has_components) > } > > regmap_config = ingenic_drm_regmap_config; > - regmap_config.max_register = res->end - res->start; > + regmap_config.max_register = resource_size(res); These two are not equivalent. resource_size() is (res->end - res->start + 1). If the memory resource has a size of 0x10 bytes, then using resource_size() will set .max_register == 0x10, which is invalid, as it is already outside the memory resource. Cheers, -Paul > priv->map = devm_regmap_init_mmio(dev, base, > ®map_config); > if (IS_ERR(priv->map)) { > -- > 2.20.1.7.g153144c >
diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c index 2c559885347a..5514b163999f 100644 --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c @@ -1146,7 +1146,7 @@ static int ingenic_drm_bind(struct device *dev, bool has_components) } regmap_config = ingenic_drm_regmap_config; - regmap_config.max_register = res->end - res->start; + regmap_config.max_register = resource_size(res); priv->map = devm_regmap_init_mmio(dev, base, ®map_config); if (IS_ERR(priv->map)) {
This was found by coccicheck: ./drivers/gpu/drm/ingenic/ingenic-drm-drv.c:1149:35-38: WARNING: Suspicious code. resource_size is maybe missing with res. Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> --- drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)