Return-Path: Message-Id: <20130813155837.694628223@goodmis.org> Date: Tue, 13 Aug 2013 11:58:21 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Wanpeng Li , Michal Hocko , KAMEZAWA Hiroyuki , David Rientjes , Andrew Morton Subject: [87/88] mm/memory-hotplug: fix lowmem count overflow when offline pages References: <20130813155654.069291373@goodmis.org> Content-Disposition: inline; filename=0087-mm-memory-hotplug-fix-lowmem-count-overflow-when-off.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.6.11.7-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Wanpeng Li [ Upstream commit cea27eb2a202959783f81254c48c250ddd80e129 ] The logic for the memory-remove code fails to correctly account the Total High Memory when a memory block which contains High Memory is offlined as shown in the example below. The following patch fixes it. Before logic memory remove: MemTotal: 7603740 kB MemFree: 6329612 kB Buffers: 94352 kB Cached: 872008 kB SwapCached: 0 kB Active: 626932 kB Inactive: 519216 kB Active(anon): 180776 kB Inactive(anon): 222944 kB Active(file): 446156 kB Inactive(file): 296272 kB Unevictable: 0 kB Mlocked: 0 kB HighTotal: 7294672 kB HighFree: 5704696 kB LowTotal: 309068 kB LowFree: 624916 kB After logic memory remove: MemTotal: 7079452 kB MemFree: 5805976 kB Buffers: 94372 kB Cached: 872000 kB SwapCached: 0 kB Active: 626936 kB Inactive: 519236 kB Active(anon): 180780 kB Inactive(anon): 222944 kB Active(file): 446156 kB Inactive(file): 296292 kB Unevictable: 0 kB Mlocked: 0 kB HighTotal: 7294672 kB HighFree: 5181024 kB LowTotal: 4294752076 kB LowFree: 624952 kB [mhocko@suse.cz: fix CONFIG_HIGHMEM=n build] Signed-off-by: Wanpeng Li Reviewed-by: Michal Hocko Cc: KAMEZAWA Hiroyuki Cc: David Rientjes Cc: [2.6.24+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Steven Rostedt --- mm/page_alloc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d2d8f54..74ebc00 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5936,6 +5936,10 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) list_del(&page->lru); rmv_page_order(page); zone->free_area[order].nr_free--; +#ifdef CONFIG_HIGHMEM + if (PageHighMem(page)) + totalhigh_pages -= 1 << order; +#endif __mod_zone_page_state(zone, NR_FREE_PAGES, - (1UL << order)); for (i = 0; i < (1 << order); i++) -- 1.7.10.4