linux framebuffer ioctls

[Alexander Shishkin]

Hi,

I've just stumbled upon a funny issue regarding FBIOGET_FSCREENINFO
ioctl command. What it does is filling in a structure called
fb_fix_screeninfo (fb.h) and passes it to userspace. Now the problem
is that if you run 32-bit userspace with a 64-bit kernel, you have
problems because of 2 unsigned long fields in the abovementioned
structure:

unsigned long smem_start; /* Start of frame buffer mem */
...
unsigned long mmio_start; /* Start of Memory Mapped I/O */

Most of the structure fields that follow smem_start get screwed from
32-bit userspace point.
I take it that applications somehow make use of these fields (at least
kdrive's fbdev does, from what I see).
Now the question is, how do we get around this situation?

--
I am free of all prejudices. I hate every one equally.
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