Re: bootmem: Double freeing a PFN on nodes spanning other nodes

From: Johannes Weiner
Date: Sun May 18 2008 - 21:31:43 EST


KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> writes:

> On Sat, 17 May 2008 00:30:55 +0200
> Johannes Weiner <hannes@xxxxxxxxxxxx> wrote:
>
>> Hi,
>>
>> When memory nodes overlap each other, the bootmem allocator is not aware
>> of this and might pass the same page twice to __free_pages_bootmem().
>>
>
> 1. init_bootmem_node() is called against a node, [start, end). After this,
> all pages are 'allocated'.
> 2. free_bootmem_node() is called against available memory in a node.
> 3. bootmem allocator is ready.
>
> memory overlap seems not to be trouble while an arch's code calls
> free_bootmem_node() correctly.

Ah, I totally overlooked that one. Thank you very much!

Hannes
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