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Date: Sat, 26 Apr 2008 14:11:39 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Adrian Bunk <bunk@kernel.org>
cc: Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
       "H. Peter Anvin" <hpa@zytor.com>, Yinghai Lu <yinghai.lu@sun.com>,
       Yinghai Lu <yhlu.kernel@gmail.com>, jbarnes@virtuousgeek.org
Subject: Re: [git pull] "big box" x86 changes, boot protocol
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On Sun, 27 Apr 2008, Adrian Bunk wrote:

> On Sat, Apr 26, 2008 at 01:39:28PM -0700, Andrew Morton wrote:
> > On Sat, 26 Apr 2008 21:54:07 +0200 Ingo Molnar <mingo@elte.hu> wrote:
> >...
> > > +
> > > +	memcpy(&early_res[i], &early_res[i + 1],
> > > +	       (j - 1 - i) * sizeof(struct early_res));
> > 
> > nit: memcpy() shouldn't be used for overlapping copies.  It happens to be
> > OK (for dst<src) in the kernel implementations.  We hope.
> >...
> 
> We always use the gcc builtin for memcpy() here.

It's probably hard to write a reasonable x86 memcpy() that wouldn't happen 
to do the right thing for this case, but I do agee - we should still use 
memmove() for this, just to make it clear that it does overlapping things.

		Linus