Re: mlockall and mmap of IO devices don't mix

[Russell King]

On Sat, Oct 04, 2003 at 11:17:03AM +0200, Andi Kleen wrote:
> > This check is only done, if it is a valid pfn (pfn_valid()) of a present
> > pte.
> 
> pfn_valid is useless, it doesn't handle all IO holes on x86 for examples.

Sounds like pfn_valid() is buggy on x86.  It's supposed to definitively
indicate whether the PFN is a valid page of ram (and has a valid struct
page entry.)  If it doesn't do that, the architecture implementation is
wrong.

-- 
Russell King (rmk@xxxxxxxxxxxxxxxx)	http://www.arm.linux.org.uk/personal/
      Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
      maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                      2.6 Serial core
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