Message ID | 54f7d42e07eca2a2f13669575a9de88023ebc1ac.1603788512.git.yepeilin.cs@gmail.com (mailing list archive) |
---|---|
State | Not Applicable |
Headers | show |
Series | None | expand |
On Tue, Oct 27, 2020 at 12:33:05PM -0400, Peilin Ye wrote: > It is improper to define `width` and `height` as signed in `struct > font_desc`. Make them unsigned. Also, change the corresponding printk() > format identifiers from `%d` to `%u`, in sti_select_fbfont(). > > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> I'm not entirely sure of the motivation here ... height/width should never ever be even close to the limit here. Or have you seen integer math that could potentially go wrong if we go with unsigned instead of int? -Daniel > --- > Build-tested. > > drivers/video/console/sticore.c | 2 +- > include/linux/font.h | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/video/console/sticore.c b/drivers/video/console/sticore.c > index 6a26a364f9bd..d1bb5915082b 100644 > --- a/drivers/video/console/sticore.c > +++ b/drivers/video/console/sticore.c > @@ -502,7 +502,7 @@ sti_select_fbfont(struct sti_cooked_rom *cooked_rom, const char *fbfont_name) > if (!fbfont) > return NULL; > > - pr_info("STI selected %dx%d framebuffer font %s for sticon\n", > + pr_info("STI selected %ux%u framebuffer font %s for sticon\n", > fbfont->width, fbfont->height, fbfont->name); > > bpc = ((fbfont->width+7)/8) * fbfont->height; > diff --git a/include/linux/font.h b/include/linux/font.h > index b5b312c19e46..4f50d736ea72 100644 > --- a/include/linux/font.h > +++ b/include/linux/font.h > @@ -16,7 +16,7 @@ > struct font_desc { > int idx; > const char *name; > - int width, height; > + unsigned int width, height; > const void *data; > int pref; > }; > -- > 2.25.1 >
On Tue, Oct 27, 2020 at 07:50:58PM +0100, Daniel Vetter wrote: > On Tue, Oct 27, 2020 at 12:33:05PM -0400, Peilin Ye wrote: > > It is improper to define `width` and `height` as signed in `struct > > font_desc`. Make them unsigned. Also, change the corresponding printk() > > format identifiers from `%d` to `%u`, in sti_select_fbfont(). > > > > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> > > I'm not entirely sure of the motivation here ... height/width should never > ever be even close to the limit here. Or have you seen integer math that > could potentially go wrong if we go with unsigned instead of int? Oh... No, I have not. I just thought we shouldn't represent a length using a signed value. Also, width and height in console_font are unsigned int - that shouldn't matter that much though. [3/5] doesn't hunk properly without this patch, I'll send a v2 for [3/5] soon. Peilin
On Wed, Oct 28, 2020 at 01:43:07AM -0400, Peilin Ye wrote: > On Tue, Oct 27, 2020 at 07:50:58PM +0100, Daniel Vetter wrote: > > On Tue, Oct 27, 2020 at 12:33:05PM -0400, Peilin Ye wrote: > > > It is improper to define `width` and `height` as signed in `struct > > > font_desc`. Make them unsigned. Also, change the corresponding printk() > > > format identifiers from `%d` to `%u`, in sti_select_fbfont(). > > > > > > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> > > > > I'm not entirely sure of the motivation here ... height/width should never > > ever be even close to the limit here. Or have you seen integer math that > > could potentially go wrong if we go with unsigned instead of int? > > Oh... No, I have not. I just thought we shouldn't represent a length > using a signed value. Also, width and height in console_font are > unsigned int - that shouldn't matter that much though. Oh this is actually a good reason, since that's the uapi structure. And so using the exact same signedness should help a bit with accidental casting bugs. If you mention this in the commit message I think this is good to go. -Daniel > > [3/5] doesn't hunk properly without this patch, I'll send a v2 for [3/5] > soon. > > Peilin >
On Wed, Oct 28, 2020 at 09:18:44AM +0100, Daniel Vetter wrote: > On Wed, Oct 28, 2020 at 01:43:07AM -0400, Peilin Ye wrote: > > On Tue, Oct 27, 2020 at 07:50:58PM +0100, Daniel Vetter wrote: > > > On Tue, Oct 27, 2020 at 12:33:05PM -0400, Peilin Ye wrote: > > > > It is improper to define `width` and `height` as signed in `struct > > > > font_desc`. Make them unsigned. Also, change the corresponding printk() > > > > format identifiers from `%d` to `%u`, in sti_select_fbfont(). > > > > > > > > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> > > > > > > I'm not entirely sure of the motivation here ... height/width should never > > > ever be even close to the limit here. Or have you seen integer math that > > > could potentially go wrong if we go with unsigned instead of int? > > > > Oh... No, I have not. I just thought we shouldn't represent a length > > using a signed value. Also, width and height in console_font are > > unsigned int - that shouldn't matter that much though. > > Oh this is actually a good reason, since that's the uapi structure. And so > using the exact same signedness should help a bit with accidental casting > bugs. > > If you mention this in the commit message I think this is good to go. Ah, I see, v2 on the way. Please ignore [v2 3/5], that doesn't hunk with this patch in effect... One newbie question, should I mention in the commit message, if a patch depends on another patch in the series in order to hunk properly? Peilin
On Wed, Oct 28, 2020 at 06:56:47AM -0400, Peilin Ye wrote: > `width` and `height` are defined as unsigned in our UAPI font descriptor > `struct console_font`. Make them unsigned in our kernel font descriptor > `struct font_desc`, too. > > Also, change the corresponding printk() format identifiers from `%d` to > `%u`, in sti_select_fbfont(). > > Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> Pushed to drm-misc-next, thanks for the patch. -Daniel > --- > Change in v2: > - Mention `struct console_font` in the commit message. (Suggested by > Daniel Vetter <daniel@ffwll.ch>) > > drivers/video/console/sticore.c | 2 +- > include/linux/font.h | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/video/console/sticore.c b/drivers/video/console/sticore.c > index 6a26a364f9bd..d1bb5915082b 100644 > --- a/drivers/video/console/sticore.c > +++ b/drivers/video/console/sticore.c > @@ -502,7 +502,7 @@ sti_select_fbfont(struct sti_cooked_rom *cooked_rom, const char *fbfont_name) > if (!fbfont) > return NULL; > > - pr_info("STI selected %dx%d framebuffer font %s for sticon\n", > + pr_info("STI selected %ux%u framebuffer font %s for sticon\n", > fbfont->width, fbfont->height, fbfont->name); > > bpc = ((fbfont->width+7)/8) * fbfont->height; > diff --git a/include/linux/font.h b/include/linux/font.h > index b5b312c19e46..4f50d736ea72 100644 > --- a/include/linux/font.h > +++ b/include/linux/font.h > @@ -16,7 +16,7 @@ > struct font_desc { > int idx; > const char *name; > - int width, height; > + unsigned int width, height; > const void *data; > int pref; > }; > -- > 2.25.1 >
diff --git a/drivers/video/console/sticore.c b/drivers/video/console/sticore.c index 6a26a364f9bd..d1bb5915082b 100644 --- a/drivers/video/console/sticore.c +++ b/drivers/video/console/sticore.c @@ -502,7 +502,7 @@ sti_select_fbfont(struct sti_cooked_rom *cooked_rom, const char *fbfont_name) if (!fbfont) return NULL; - pr_info("STI selected %dx%d framebuffer font %s for sticon\n", + pr_info("STI selected %ux%u framebuffer font %s for sticon\n", fbfont->width, fbfont->height, fbfont->name); bpc = ((fbfont->width+7)/8) * fbfont->height; diff --git a/include/linux/font.h b/include/linux/font.h index b5b312c19e46..4f50d736ea72 100644 --- a/include/linux/font.h +++ b/include/linux/font.h @@ -16,7 +16,7 @@ struct font_desc { int idx; const char *name; - int width, height; + unsigned int width, height; const void *data; int pref; };
It is improper to define `width` and `height` as signed in `struct font_desc`. Make them unsigned. Also, change the corresponding printk() format identifiers from `%d` to `%u`, in sti_select_fbfont(). Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> --- Build-tested. drivers/video/console/sticore.c | 2 +- include/linux/font.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)