Re: [patch, 2.5] __vmalloc allocates spurious page?

Russell King (rmk@arm.linux.org.uk)
Tue, 15 Oct 2002 23:05:06 +0100


On Wed, Oct 16, 2002 at 12:58:12AM +0300, Marcus Alanen wrote:
> >The unnecessary page is allocated only if size is initially a multiple
> >of PAGE_SIZE, which sounds like a common case.
>
> Actually, size is already PAGE_ALIGNed, so we get the amount of pages
> even easier.

IIRC, back in the dim and distant past, the extra page was originally to
catch things running off the end of their space (eg, modules). The
idea was that modules (and other vmalloc'd areas) would be separated
by one unmapped page.

It looks like this got broken recently though.

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html

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