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Date: Mon, 08 Sep 2014 19:27:14 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: James Bottomley <James.Bottomley@HansenPartnership.com>,
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Subject: Re: bit fields && data tearing
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On 09/08/2014 03:43 PM, James Bottomley wrote:
> 
> This was years ago (possibly decades).  We had to implement in-kernel
> unaligned traps for the networking layer because it could access short
> and int fields that weren't of the correct alignment when processing
> packets.  It that's all corrected now, we wouldn't really notice (except
> a bit of a speed up since an unaligned trap effectively places the
> broken out instructions into the bit stream).
> 
> James
> 

Well, ARM doesn't trap, it just silently gives garbage on unaligned
memory references.

	-hpa