On Sun, May 26, 2013 at 07:49:33AM -0400, KOSAKI Motohiro wrote: >On Sun, May 26, 2013 at 1:58 AM, Wanpeng Li <liwanp@xxxxxxxxxxxxxxxxxx> wrote: >> Changelog: >> v1 -> v2: >> * show number of HighTotal before hotremove >> * remove CONFIG_HIGHMEM >> * cc stable kernels >> * add Michal reviewed-by >> >> Logic 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. >> >> Stable for 2.6.24+. >> >> 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 >> >> Reviewed-by: Michal Hocko <mhocko@xxxxxxx> >> Signed-off-by: Wanpeng Li <liwanp@xxxxxxxxxxxxxxxxxx> >> --- >> mm/page_alloc.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index 98cbdf6..23b921f 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -6140,6 +6140,8 @@ __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--; >> + if (PageHighMem(page)) >> + totalhigh_pages -= 1 << order; >> for (i = 0; i < (1 << order); i++) >> SetPageReserved((page+i)); >> pfn += (1 << order); > >Hm. I already NAKed and you didn't answered my question. isn't it? Jiang makes his effort to support highmem for memory hotremove, he also fix this bug, http://marc.info/?l=linux-mm&m=136957578620221&w=2 -- 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>