From: Xishi Qiu <qiuxishi@xxxxxxxxxx> Hi all, There may be have a bug when register section info. For example, on an Itanium platform, the pfn range of node0 includes the other nodes. So when hot remove memory, we can't free the memmap's page because page_count() is 2 after put_page_bootmem(). sparse_remove_one_section()->free_section_usemap()->free_map_bootmem() ->put_page_bootmem() pgdat0: start_pfn=0x100, spanned_pfn=0x20fb00, present_pfn=0x7f8a3, => 0x100-0x20fc00 pgdat1: start_pfn=0x80000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x80000-0x100000 pgdat2: start_pfn=0x100000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x100000-0x180000 pgdat3: start_pfn=0x180000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x180000-0x200000 Signed-off-by: Xishi Qiu <qiuxishi@xxxxxxxxxx> --- mm/memory_hotplug.c | 10 ++++------ 1 files changed, 4 insertions(+), 6 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 2adbcac..cf493c7 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -126,9 +126,6 @@ static void register_page_bootmem_info_section(unsigned long start_pfn) struct mem_section *ms; struct page *page, *memmap; - if (!pfn_valid(start_pfn)) - return; - section_nr = pfn_to_section_nr(start_pfn); ms = __nr_to_section(section_nr); @@ -187,9 +184,10 @@ void register_page_bootmem_info_node(struct pglist_data *pgdat) end_pfn = pfn + pgdat->node_spanned_pages; /* register_section info */ - for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) - register_page_bootmem_info_section(pfn); - + for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) { + if (pfn_valid(pfn) && (pfn_to_nid(pfn) == node)) + register_page_bootmem_info_section(pfn); + } } #endif /* !CONFIG_SPARSEMEM_VMEMMAP */ -- 1.7.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>