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Date: Wed, 02 Nov 2011 19:09:55 -0400 (EDT)
Message-Id: <20111102.190955.1902322759075682192.davem@davemloft.net>
To: eric.dumazet@gmail.com
Cc: tony@atomide.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-omap@vger.kernel.org
Subject: Re: [PATCH] net: Add back alignment for size for __alloc_skb
From: David Miller <davem@davemloft.net>
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References: <20111102224317.GM31337@atomide.com>
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 02 Nov 2011 23:55:11 +0100

> There is a problem with your kmalloc() or alignments on your architecture.
> 
> What is the SMP_CACHE_BYTES value ?

kmalloc() behavior doesn't have anything to do with this bug.

The issue is calculation of skb->end, which is based upon calculated
'size' variable.

skb->end determines alignment of skb_shared_info, which is where the
alignment problem is occuring for Tony.