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Date: Wed, 21 Feb 2007 12:36:11 -0800 (PST)
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH]add epoll compat code to fsl/compat.c
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To: Davide Libenzi <davidel@xmailserver.org>
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On Wed, 21 Feb 2007, Davide Libenzi wrote:
> 
> I don't think we can safely assume that we can access a potentially 
> 4-bytes aligned u64 on 64 bit architectures that require compat:
> 
> 	put_user(ev.data, &events->data);

Oh, we can. "put_user()" and "get_user()" already have to work on totally 
unaligned data. If some architecture has problems with that, they have 
bigger issues, methinks.

We can't trust user pointers, and that includes not trusting them being 
aligned. 

		Linus