From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758672Ab2EOLr2 (ORCPT ); Tue, 15 May 2012 07:47:28 -0400 Received: from zene.cmpxchg.org ([85.214.230.12]:59661 "EHLO zene.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758518Ab2EOLr1 (ORCPT ); Tue, 15 May 2012 07:47:27 -0400 Date: Tue, 15 May 2012 13:47:16 +0200 From: Johannes Weiner To: Andrew Morton Cc: Gavin Shan , David Miller , Yinghai Lu , Tejun Heo , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch 10/10] mm: remove sparsemem allocation details from the bootmem allocator Message-ID: <20120515114716.GI1406@cmpxchg.org> References: <1336390672-14421-1-git-send-email-hannes@cmpxchg.org> <1336390672-14421-11-git-send-email-hannes@cmpxchg.org> <20120510144439.eba9c486.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120510144439.eba9c486.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 10, 2012 at 02:44:39PM -0700, Andrew Morton wrote: > On Mon, 7 May 2012 13:37:52 +0200 > Johannes Weiner wrote: > > > alloc_bootmem_section() derives allocation area constraints from the > > specified sparsemem section. This is a bit specific for a generic > > memory allocator like bootmem, though, so move it over to sparsemem. > > > > As __alloc_bootmem_node_nopanic() already retries failed allocations > > with relaxed area constraints, the fallback code in sparsemem.c can be > > removed and the code becomes a bit more compact overall. > > > > ... > > > > @@ -332,9 +334,9 @@ static void __init check_usemap_section_nr(int nid, unsigned long *usemap) > > #else > > static unsigned long * __init > > sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat, > > - unsigned long count) > > + unsigned long size) > > { > > - return NULL; > > + return alloc_bootmem_node_nopanic(pgdat, size) > > You've been bad. Your penance is to runtime test this code with > CONFIG_MEMORY_HOTREMOVE=n! I did now. See, but I DID test the =y case, missed an obvious bug and even considered the particular node-section dependency warnings to be expected in the setup configuration. Testing is no way around being a cretin :( So here is another fix: --- From: Johannes Weiner Subject: [patch] mm: remove sparsemem allocation details from the bootmem allocator fix Don't confuse an address with a pfn. Signed-off-by: Johannes Weiner --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/sparse.c b/mm/sparse.c index 2192b67..66d1845 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -288,7 +288,7 @@ sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat, * this problem. */ goal = __pa(pgdat) & PAGE_SECTION_MASK; - host_pgdat = NODE_DATA(early_pfn_to_nid(goal)); + host_pgdat = NODE_DATA(early_pfn_to_nid(goal >> PAGE_SHIFT)); printk("allocating usemap for node %d on node %d (goal=%lu)\n", pgdat->node_id, host_pgdat->node_id, goal); return __alloc_bootmem_node_nopanic(host_pgdat, size, -- 1.7.10.1