[PATCH v3 3/4] fbmem: Check screen resolution change against font size

[Daniel Vetter]

On Sun, Jun 26, 2022 at 12:33:53AM +0200, Daniel Vetter wrote:
> On Sun, Jun 26, 2022 at 12:06:29AM +0200, Helge Deller wrote:
> > Enhance the check in the FBIOPUT_VSCREENINFO ioctl handler to verify if the
> > user-provided new screen size is bigger than the current font size.
> > 
> > Signed-off-by: Helge Deller <deller at gmx.de>
> > Cc: stable at vger.kernel.org # v5.4+
> 
> Please squash with previous patch. You might also want to add a note there
> that on older kernels backporters need to open-code
> fbcon_info_from_console instead, since it only exists since 
> 409d6c95f9c6 ("fbcon: Introduce wrapper for console->fb_info lookup")

Maybe easier would be to include that patch in the backports instead of
open coding. I think that's what Greg generally prefers at least, less
divergence between stable kernels.
-Daniel

> 
> With these two nits: Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> 
> > ---
> >  drivers/video/fbdev/core/fbmem.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
> > index afa2863670f3..160389365a36 100644
> > --- a/drivers/video/fbdev/core/fbmem.c
> > +++ b/drivers/video/fbdev/core/fbmem.c
> > @@ -1106,7 +1106,9 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
> >  			return -EFAULT;
> >  		console_lock();
> >  		lock_fb_info(info);
> > -		ret = fb_set_var(info, &var);
> > +		ret = fbcon_modechange_possible(info, &var);
> > +		if (!ret)
> > +			ret = fb_set_var(info, &var);
> >  		if (!ret)
> >  			fbcon_update_vcs(info, var.activate & FB_ACTIVATE_ALL);
> >  		unlock_fb_info(info);
> > --
> > 2.35.3
> > 
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch