From 678ff896a37afdbca292c7846ec895463aed35a5 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Thu, 10 Feb 2011 15:01:36 -0800 Subject: [PATCH] memcg: fix leak of accounting at failure path of hugepage collapsing mem_cgroup_uncharge_page() should be called in all failure cases after mem_cgroup_charge_newpage() is called in huge_memory.c::collapse_huge_page() [ 4209.076861] BUG: Bad page state in process khugepaged pfn:1e9800 [ 4209.077601] page:ffffea0006b14000 count:0 mapcount:0 mapping: (null) index:0x2800 [ 4209.078674] page flags: 0x40000000004000(head) [ 4209.079294] pc:ffff880214a30000 pc->flags:2146246697418756 pc->mem_cgroup:ffffc9000177a000 [ 4209.082177] (/A) [ 4209.082500] Pid: 31, comm: khugepaged Not tainted 2.6.38-rc3-mm1 #1 [ 4209.083412] Call Trace: [ 4209.083678] [] ? bad_page+0xe4/0x140 [ 4209.084240] [] ? free_pages_prepare+0xd6/0x120 [ 4209.084837] [] ? rwsem_down_failed_common+0xbd/0x150 [ 4209.085509] [] ? __free_pages_ok+0x32/0xe0 [ 4209.086110] [] ? free_compound_page+0x1b/0x20 [ 4209.086699] [] ? __put_compound_page+0x1c/0x30 [ 4209.087333] [] ? put_compound_page+0x4d/0x200 [ 4209.087935] [] ? put_page+0x45/0x50 [ 4209.097361] [] ? khugepaged+0x9e9/0x1430 [ 4209.098364] [] ? autoremove_wake_function+0x0/0x40 [ 4209.099121] [] ? khugepaged+0x0/0x1430 [ 4209.099780] [] ? kthread+0x96/0xa0 [ 4209.100452] [] ? kernel_thread_helper+0x4/0x10 [ 4209.101214] [] ? kthread+0x0/0xa0 [ 4209.101842] [] ? kernel_thread_helper+0x0/0x10 Signed-off-by: KAMEZAWA Hiroyuki Acked-by: Daisuke Nishimura Reviewed-by: Johannes Weiner Cc: Andrea Arcangeli Reviewed-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/huge_memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index b6c1ce3..e62ddb8 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1852,7 +1852,6 @@ static void collapse_huge_page(struct mm_struct *mm, set_pmd_at(mm, address, pmd, _pmd); spin_unlock(&mm->page_table_lock); anon_vma_unlock(vma->anon_vma); - mem_cgroup_uncharge_page(new_page); goto out; } @@ -1898,6 +1897,7 @@ out_up_write: return; out: + mem_cgroup_uncharge_page(new_page); #ifdef CONFIG_NUMA put_page(new_page); #endif -- 2.7.4