Hi

Am 03.05.23 um 11:51 schrieb Geert Uytterhoeven:

On Fri, Apr 28, 2023 at 2:26 PM Thomas Zimmermann [off-list ref] wrote:

quoted

Push the test for info->screen_base from fb_read() and fb_write() into
the implementations of struct fb_ops.{fb_read,fb_write}. In cases where
the driver operates on info->screen_buffer, test this field instead.

While bothi fields, screen_base and screen_buffer, are stored in the

both

quoted

same location, they refer to different address spaces. For correctness,
we want to test each field in exactly the code that uses it.

Not a direct comment for this patch: and later the union can be split
in two separate fields, to protect against misuse?

No idea. Currently we have sparse that warns about mismatching address 
spaces if the fields are mixed up. That's good enough, as far I'm concerned.

Best regards
Thomas

Gr{oetje,eeting}s,

                         Geert


--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@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

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
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