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 ESMTP id 310DA6B00EE for ; Wed, 8 Jun 2011 06:15:28 -0400 (EDT) Date: Wed, 8 Jun 2011 12:15:11 +0200 From: Johannes Weiner Subject: Re: [Bugme-new] [Bug 36192] New: Kernel panic when boot the 2.6.39+ kernel based off of 2.6.32 kernel Message-ID: <20110608101511.GD17886@cmpxchg.org> References: <20110607084530.8ee571aa.kamezawa.hiroyu@jp.fujitsu.com> <20110607084530.GI5247@suse.de> <20110607174355.fde99297.kamezawa.hiroyu@jp.fujitsu.com> <20110607090900.GK5247@suse.de> <20110607183302.666115f1.kamezawa.hiroyu@jp.fujitsu.com> <20110607101857.GM5247@suse.de> <20110608084034.29f25764.kamezawa.hiroyu@jp.fujitsu.com> <20110608094219.823c24f7.kamezawa.hiroyu@jp.fujitsu.com> <20110608074350.GP5247@suse.de> <20110608174505.e4be46d6.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110608174505.e4be46d6.kamezawa.hiroyu@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org List-ID: To: KAMEZAWA Hiroyuki Cc: Mel Gorman , Andrew Morton , linux-mm@kvack.org, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, qcui@redhat.com, Daisuke Nishimura , Li Zefan On Wed, Jun 08, 2011 at 05:45:05PM +0900, KAMEZAWA Hiroyuki wrote: > @@ -196,7 +195,11 @@ static int __meminit init_section_page_cgroup(unsigned long pfn) > pc = base + index; > init_page_cgroup(pc, nr); > } > - > + /* > + * Even if passed 'pfn' is not aligned to section, we need to align > + * it to section boundary because of SPARSEMEM pfn calculation. > + */ > + pfn = pfn & ~(PAGES_PER_SECTION - 1); PAGE_SECTION_MASK? > section->page_cgroup = base - pfn; > total_usage += table_size; > return 0; > @@ -228,7 +231,7 @@ int __meminit online_page_cgroup(unsigned long start_pfn, > for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) { > if (!pfn_present(pfn)) > continue; > - fail = init_section_page_cgroup(pfn); > + fail = init_section_page_cgroup(pfn, nid); AFAICS, nid can be -1 in the hotplug callbacks when there is a new section added to a node that already has memory, and then the allocation will fall back to numa_node_id(). So I think we either need to trust start_pfn has valid mem map backing it (ARM has no memory hotplug support) and use pfn_to_nid(start_pfn), or find another way to the right node, no? > @@ -285,14 +288,36 @@ void __init page_cgroup_init(void) > { > unsigned long pfn; > int fail = 0; > + int nid; > > if (mem_cgroup_disabled()) > return; > > - for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) { > - if (!pfn_present(pfn)) > - continue; > - fail = init_section_page_cgroup(pfn); > + for_each_node_state(nid, N_HIGH_MEMORY) { > + unsigned long start_pfn, end_pfn; > + > + start_pfn = NODE_DATA(nid)->node_start_pfn; > + end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages; > + /* > + * Because we cannot trust page->flags of page out of node > + * boundary, we skip pfn < start_pfn. > + */ > + for (pfn = start_pfn; > + !fail && (pfn < end_pfn); > + pfn = ALIGN(pfn + 1, PAGES_PER_SECTION)) { If we don't bother to align the pfn on the first iteration, I don't think we should for subsequent iterations. init_section_page_cgroup() has to be able to cope anyway. How about pfn += PAGES_PER_SECTION instead? -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org