From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 0E12F6B004D for ; Tue, 7 Jul 2009 18:06:30 -0400 (EDT) Subject: Re: [RFC PATCH 2/3] kmemleak: Add callbacks to the bootmem allocator From: Catalin Marinas In-Reply-To: <20090707165350.GA2782@cmpxchg.org> References: <20090706104654.16051.44029.stgit@pc1117.cambridge.arm.com> <20090706105155.16051.59597.stgit@pc1117.cambridge.arm.com> <1246950530.24285.7.camel@penberg-laptop> <20090707165350.GA2782@cmpxchg.org> Content-Type: text/plain Date: Tue, 07 Jul 2009 23:09:46 +0100 Message-Id: <1247004586.5710.16.camel@pc1117.cambridge.arm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Johannes Weiner Cc: Pekka Enberg , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ingo Molnar List-ID: On Tue, 2009-07-07 at 18:53 +0200, Johannes Weiner wrote: > On Tue, Jul 07, 2009 at 10:08:50AM +0300, Pekka Enberg wrote: > > On Mon, 2009-07-06 at 11:51 +0100, Catalin Marinas wrote: > > > @@ -597,7 +601,9 @@ restart: > > > void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align, > > > unsigned long goal) > > > { > > > - return ___alloc_bootmem_nopanic(size, align, goal, 0); > > > + void *ptr = ___alloc_bootmem_nopanic(size, align, goal, 0); > > > + kmemleak_alloc(ptr, size, 1, GFP_KERNEL); > > > + return ptr; > > You may get an object from kzalloc() here, I don't think you want to > track that (again), right? You are write, I missed the alloc_arch_preferred_bootmem() function which may call kzalloc(). > Pekka already worked out all the central places to catch 'slab already > available' allocations, they can probably help you place the hooks. It seems that alloc_bootmem_core() is central to all the bootmem allocations. Is it OK to place the kmemleak_alloc hook only in this function? diff --git a/mm/bootmem.c b/mm/bootmem.c index 5a649a0..74cbb34 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -520,6 +520,7 @@ find_block: region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) + start_off); memset(region, 0, size); + kmemleak_alloc(region, size, 1, 0); return region; } > > > + kmemleak_alloc(ptr, size, 1, GFP_KERNEL); > > These GFP_KERNEL startled me. We know for sure that this code runs in > earlylog mode only and gfp is unused, right? Can you perhaps just > pass 0 for gfp instead? Yes, indeed. Thanks for your comments. -- Catalin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org