From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olivier Matz <olivier.matz@6wind.com>
Subject: Re: [PATCH] mempool: adjust name string size in related
	data types
Date: Tue, 19 Jul 2016 17:37:28 +0200
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References: <1468939061-19734-1-git-send-email-zoltan.kiss@schaman.hu>
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To: Zoltan Kiss <zoltan.kiss@schaman.hu>, dev@dpdk.org
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Hi Zoltan,

On 07/19/2016 04:37 PM, Zoltan Kiss wrote:
> A recent fix brought up an issue about the size of the 'name' fields:
> 
> 85cf0079 mem: avoid memzone/mempool/ring name truncation
> 
> These relations should be observed:
> 
> RTE_RING_NAMESIZE <= RTE_MEMZONE_NAMESIZE - strlen(RTE_RING_MZ_PREFIX)
> RTE_MEMPOOL_NAMESIZE <= RTE_RING_NAMESIZE - strlen(RTE_MEMPOOL_MZ_PREFIX)
> 
> Setting all of them to 32 hides this restriction from the application.
> This patch increases the memzone string size to accomodate for these
> prefixes, and the same happens with the ring name string. The ABI needs to
> be broken to fix this API issue, this way doesn't break applications
> previously not failing due to the truncating bug now fixed.
> 
> Signed-off-by: Zoltan Kiss <zoltan.kiss@schaman.hu>

I agree it is a problem for an application because it cannot know what
is the maximum name length. On the other hand, breaking the ABI for this
looks a bit overkill. Maybe we could reduce RTE_MEMPOOL_NAMESIZE and
RTE_RING_NAMESIZE instead of increasing RTE_MEMZONE_NAMESIZE? That way,
we could keep the ABI as is.

It would even be better to get rid of this static char[] for the
structure names and replace it by an allocated const char *. I didn't
check it's feasible for memzones. What do you think?

In any case, I think it's a bit late for 16.07 for this kind of fix.

Regards,
Olivier