Re: bit fields && data tearing

From: H. Peter Anvin
Date: Mon Sep 08 2014 - 22:33:41 EST


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


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