From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757553AbYLKRp2 (ORCPT ); Thu, 11 Dec 2008 12:45:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756687AbYLKRpN (ORCPT ); Thu, 11 Dec 2008 12:45:13 -0500 Received: from e38.co.us.ibm.com ([32.97.110.159]:53782 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756592AbYLKRpL (ORCPT ); Thu, 11 Dec 2008 12:45:11 -0500 Subject: Re: [PATCH 07/15] kmemleak: Add memleak_alloc callback from alloc_large_system_hash From: Dave Hansen To: Catalin Marinas Cc: linux-kernel@vger.kernel.org In-Reply-To: <1229017098.332.45.camel@pc1117.cambridge.arm.com> References: <20081210182652.30323.4594.stgit@pc1117.cambridge.arm.com> <20081210182732.30323.39834.stgit@pc1117.cambridge.arm.com> <1228935860.9737.98.camel@nimitz> <1228989052.332.12.camel@pc1117.cambridge.arm.com> <1229016618.17206.2.camel@nimitz> <1229017098.332.45.camel@pc1117.cambridge.arm.com> Content-Type: text/plain Date: Thu, 11 Dec 2008 09:45:06 -0800 Message-Id: <1229017506.17206.7.camel@nimitz> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2008-12-11 at 17:38 +0000, Catalin Marinas wrote: > On Thu, 2008-12-11 at 09:30 -0800, Dave Hansen wrote: > > On Thu, 2008-12-11 at 09:50 +0000, Catalin Marinas wrote: > > > > Since alloc_large_system_hash() is using bootmem (and is called early), > > > > I'm a little surprised that it is OK to call into memleak_alloc() which > > > > uses kmem_cache_alloc(). Is the slab even set up at this point? > > > > > > It doesn't need to be. Early callbacks like this are logged by kmemleak > > > in a buffer and properly registered once the slab allocator is fully > > > initialised (slab initialisation needs to allocate some memory for > > > itself as well). > > > > Ahh, thanks for the clarification. Could you add something to the code > > to this effect? > > Do you mean a comment? I can do this. Yeah, something like /* * kmemleak doesn't actually allocate memory when called this early * so the GFP_ATOMIC here is actually meaningless, but consistent * with the rest of this function. */ Maybe that's too verbose. :) -- Dave