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Date: Mon, 13 Jun 2016 17:21:01 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Jianfeng Tan <jianfeng.tan@intel.com>
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Subject: Re: [dpdk-dev] [PATCH] virtio: fix allocating virtnet_rx not mem
	aligned
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On Sun, Jun 12, 2016 at 02:29:42PM +0000, Jianfeng Tan wrote:
> Compile DPDK with clang, below line in virtio_rxtx.c could be
> optimized with four "VMOVAPS ymm, m256".
>   memset(&rxvq->fake_mbuf, 0, sizeof(rxvq->fake_mbuf));
> 
> This instruction requires memory address is 32-byte aligned.
> Or, it leads to segfault.

That looks like a dangerous optimization to me. If that's the case,
doesn't it mean we have to make sure the address is always aligned
properly while calling memset?

	--yliu