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Date: Fri, 23 May 2008 08:50:32 +0900
From: Paul Mundt <lethal@linux-sh.org>
To: Christoph Lameter <clameter@sgi.com>
Cc: Pekka J Enberg <penberg@cs.helsinki.fi>, dhowells@redhat.com,
       mpm@selenic.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] nommu: fix kobjsize() for SLOB and SLUB
Message-ID: <20080522235032.GA22697@linux-sh.org>
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	Christoph Lameter <clameter@sgi.com>,
	Pekka J Enberg <penberg@cs.helsinki.fi>, dhowells@redhat.com,
	mpm@selenic.com, linux-kernel@vger.kernel.org
References: <Pine.LNX.4.64.0805221907250.4056@sbz-30.cs.Helsinki.FI> <20080522234036.GA18434@linux-sh.org> <Pine.LNX.4.64.0805221644470.30217@schroedinger.engr.sgi.com>
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On Thu, May 22, 2008 at 04:45:55PM -0700, Christoph Lameter wrote:
> On Fri, 23 May 2008, Paul Mundt wrote:
> > Is ksize() happy with taking the head page instead of virt_to_page(objp)?
> 
> ksize() takes a pointer to an object. ksize() cannot take a the pointer to 
> a page struct.
> 
Ah, so it does. In that case, we still need to kill off the page->index
BUG_ON() bits, while PageCompound() will take care of the compound order
bits that the page->index shifting seems to have been trying to
implement, the BUG_ON() will still trigger for PAGE_SIZE page cache
pages.