[FIX] Re: 2.5.66 new fbcon oops while loading X

[bert hubert <ahu@ds9a.nl>]

On Tue, Mar 25, 2003 at 05:23:07PM +0000, James Simmons wrote:
> > While loading X, I get this oops. The weird thing is that I don't use
> > framebuffer. I compiled with gcc 3.2.2 but the code generated looks weird.
> > Virgin gcc 3.2.2 on a pentium III.
> 
> You don't use framebuffer? Can you send me your config. 

Ok, I've found the bug, it is in fb_open() in drivers/video/fbmem.c, it
needs this addition:

        if(fbidx >= FB_MAX)
                return -ENODEV;

Without it, large minor numbers result in access beyond the end of
registered_fb.

On Debian, ls /dev/fb[67] results in:
crw--w--w-    1 root     tty       29, 192 Nov 30  2000 /dev/fb6
crw--w--w-    1 root     tty       29, 224 Nov 30  2000 /dev/fb7

On Red Hat this is: 
crw-------    1 root     root      29,   7 Apr 11  2002 /dev/fb7
crw-------    1 root     root      29,   8 Apr 11  2002 /dev/fb8

Which explains why many don't see this bug.

Regards,

bert

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