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To: Olivier Matz <olivier.matz@6wind.com>, dev@dpdk.org
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From: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
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Date: Thu, 9 Jun 2016 08:57:02 +0100
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Subject: Re: [dpdk-dev] [PATCH] mempool: fix local cache initialization
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Hi Olivier,

On 08/06/2016 20:14, Olivier Matz wrote:
> Hi Sergio,
>
> Good catch, thanks. The patch looks ok, just few comments
> on the commit log:
>
> On 06/08/2016 05:10 PM, Sergio Gonzalez Monroy wrote:
>> The mempool local cache is not being initialize properly leading to
> 'initialize' -> 'initialized' ?
> and maybe 'is not being' -> 'was not' ?
>
>> undefined behavior in cases where the allocated memory was used and left
>> with data.
>>
>> Fixes: af75078fece3 ("first public release")
> I think it fixes this one instead:
>
> 213af31e0960 ("mempool: reduce structure size if no cache needed")

Fair enough, I thought the issue was there as we never 
initialized/zeroed the local cache
on mempool creation. Usually we would have allocated all mempools on 
init (or close)
and that would be it (initially all memory would be zeroed), but I think 
you could still
manage to reproduce the problem if somehow you where to do something like:
rte_malloc(), rte_free(), rte_mempool_create() and the memory was the 
one we got
with malloc and never gets zeroed again.

Sergio