[PATCH] fbmem: don't allow too huge resolutions

[Geert Uytterhoeven]

Hi Daniel,

On Tue, Aug 31, 2021 at 8:53 PM Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
> On Tue, Aug 31, 2021 at 7:19 PM Geert Uytterhoeven <geert at linux-m68k.org> wrote:
> > On Tue, Aug 31, 2021 at 5:24 PM Tetsuo Handa
> > <penguin-kernel at i-love.sakura.ne.jp> wrote:
> > > On 2021/08/31 15:48, Geert Uytterhoeven wrote:
> > > > Furthermore, this restricts the virtual frame buffer size on 64-bit,
> > > > too, while graphics cards can have much more than 4 GiB of RAM.
> > >
> > > Excuse me, but do you mean that some hardware allows allocating more than
> > > UINT_MAX bytes of memory for kernel frame buffer drivers?
> >
> > While smem_len is u32 (there have been complaints about such
> > limitations on 64-bit platforms as far as 10 years ago), I see no
> > reason why a graphics card with more than 4 GiB of RAM would not be
> > able to provide a very large virtual screen.
> >
> > Of course e.g. vga16fb cannot, as it is limited to 64 KiB.
>
> The first gpus with 4GB or more memory started shipping in 2012. We're
> not going to have fbdev drivers for these, so let's not invent code
> for use-cases that aren't please.

This code path is used with fbdev emulation for drm drivers, too,
right?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds