lkml.org 
[lkml]   [2011]   [Feb]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] x86/mm/init: respect memblock reserved regions when destroying mappings
On 01/31/2011 07:18 AM, Stefano Stabellini wrote:
> x86/mm/init: respect memblock reserved regions when destroying mappings
>
> In init_memory_mapping we are destroying all the mappings between
> _brk_end and _end, no matter if some memory areas in that range have
> been reserved using memblock_x86_reserve_range.
> Besides if _end is not pmd aligned we might destroy the
> mappings for valid memory between _end and the following pmd.
>
> In order to avoid this problem, before clearing any pmds we check if the
> corresponding memory area has been reserved and we only destroy the
> mapping if it hasn't.
>
> We found this problem because under Xen we have a valid mapping at _end,
> and if _end is not pmd aligned the current code destroys the initial
> part of it.
>
> In practice this fix does not have any impact on native.
>
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

How on Earth would you end up with a reserved region *inside the BRK*?

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.



\
 
 \ /
  Last update: 2011-02-03 06:07    [W:0.060 / U:0.612 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site