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Subject: Re: [PATCH 19/25] lmb: Add array resizing support
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Yinghai Lu <yhlu.kernel@gmail.com>
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Date: Tue, 11 May 2010 14:56:05 +1000
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On Mon, 2010-05-10 at 16:59 -0700, Yinghai Lu wrote:
> you need to pass base, base+size with lmb_double_array()
> 
> otherwise when you are using lmb_reserve(base, size), double_array()
> array could have chance to get
> new buffer that is overlapped with [base, base + size).
> 
> to keep it simple, should check_double_array() after lmb_reserve,
> lmb_add, lmb_free (yes, that need it too).
> that was suggested by Michael Ellerman.
> 

No. You may notice that I addressed this problem by moving the
call to lmb_double_array() to -after- we record the entry in
the array, so it shouldn't be able to pickup the same one.

I dislike the idea of sprinkling the check for resize everywhere at the
top level.

Cheers,
Ben.