Re: Can we kill f inb_p, outb_p and other random I/O on port 0x80, in 2.6?

[Jamie Lokier]

Eric W. Biederman wrote:
> Alan, can you describe a little more what the original delay is needed
> for?  I don't see it documented in my 8254 data sheet.  The better I
> can understand the problem the better I can write the comments on this
> magic bit of code as I fix it.
> 
> The oldest machine I have is a 386 MCA system.  Any chance of the bug
> showing up there?  I'd love to have a test case.
> 
> Another reason for fixing this is we are killing who knows how much
> I/O bandwidth with this stream of failing writes to port 0x80.

Unfortunately, a lot of drivers use the _p operators so if the delay
is simply removed, it may take a while before the ill effects of that
are discovered.

-- Jamie
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