Subject: Re: [PATCH] powerpc: change rheap functions to use long integers instead of pointers

From: Timur Tabi <[email-masked]>
Date: Wed, 04 Apr 2007 13:27:56 -0500

Scott Wood wrote:

>> The same patch should be applied to rh_detach_region() and 
>> rh_alloc_fixed().
> 
> You should check "e" instead, and make sure that s < e.

Now that I look at the code, I think there's a bug in the calculation of 'e'.  'e' is 
rounded down, and it's based on the unaligned value of 'start'.  Instead, 'size' should be 
rounded up, and 'e' should be based on 's' (i.e. the aligned value of 'start').

Otherwise, if you pass an unaligned value of 'start', then the buffer you get back will be 
less than 'size'.

-- 
Timur Tabi
Linux Kernel Developer @ Freescale