Re: BUG: fb_imageblit called before fb_check_var and fb_set_par function

["Antonino A. Daplas" <adaplas@gmail.com>]

Knut Petersen wrote:
> Hi Antonino,
> 
>> ...and the driver happily draws to the screen. No bug.
>> I believe, from here on, everything will work as expected.
>>
>> So it seems that when kdm loads the first time, it failed to set the
>> mode to KD_GRAPHICS which triggered the bug. Maybe it's a bug in
>> kdm then?
> 
> Well, it might be a kdm bug, but that bug is widely spread then. SuSE 
> 9.2 and Debian Sarge
> are affected at least. I would call it a kernel design flaw / bug if we 
> allow this kind of
> situation to happen.

Well, that's why X runs as root, and the kernel will practically do anything
for root.
 
>  But why does this happen only if kdm is started early?

I don't know. The kdm I in suse 9.0 seems not to exhibit this behavior.

> This question
> must be answered. Even if the answer is that kdm does something wrong, 
> it would be
> a good idea to call e.g. *fb_set_par() unconditionally for every console 
> switch ...

This has been discussed before.  Not all hardware can do a set_par()
instantaneously, some may require seconds.  And that will become a usability
problem. Just imagine switching from one console to another and it takes
5 seconds.

Tony



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