From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754409AbdJSPK4 (ORCPT ); Thu, 19 Oct 2017 11:10:56 -0400 Received: from mga05.intel.com ([192.55.52.43]:34779 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751626AbdJSPKz (ORCPT ); Thu, 19 Oct 2017 11:10:55 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.43,402,1503385200"; d="scan'208";a="165047998" From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Michal Hocko , "Kirill A. Shutemov" , David Rientjes , Arnd Bergmann , Hugh Dickins , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Daniel Colascione , Zi Yan , Naoya Horiguchi Subject: [PATCH -mm -V2] mm, pagemap: Fix soft dirty marking for PMD migration entry Date: Thu, 19 Oct 2017 23:10:46 +0800 Message-Id: <20171019151046.3443-1-ying.huang@intel.com> X-Mailer: git-send-email 2.14.2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huang Ying Now, when the page table is walked in the implementation of /proc//pagemap, pmd_soft_dirty() is used for both the PMD huge page map and the PMD migration entries. That is wrong, pmd_swp_soft_dirty() should be used for the PMD migration entries instead because the different page table entry flag is used. Otherwise, the soft dirty information in /proc//pagemap may be wrong. Cc: Michal Hocko Cc: "Kirill A. Shutemov" Cc: David Rientjes Cc: Arnd Bergmann Cc: Hugh Dickins Cc: "Jérôme Glisse" Cc: Daniel Colascione Cc: Zi Yan Cc: Naoya Horiguchi Signed-off-by: "Huang, Ying" Fixes: 84c3fc4e9c56 ("mm: thp: check pmd migration entry in common path") --- fs/proc/task_mmu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 2593a0c609d7..01aad772f8db 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1311,13 +1311,15 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, pmd_t pmd = *pmdp; struct page *page = NULL; - if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd)) + if (vma->vm_flags & VM_SOFTDIRTY) flags |= PM_SOFT_DIRTY; if (pmd_present(pmd)) { page = pmd_page(pmd); flags |= PM_PRESENT; + if (pmd_soft_dirty(pmd)) + flags |= PM_SOFT_DIRTY; if (pm->show_pfn) frame = pmd_pfn(pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT); @@ -1329,6 +1331,8 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, frame = swp_type(entry) | (swp_offset(entry) << MAX_SWAPFILES_SHIFT); flags |= PM_SWAP; + if (pmd_swp_soft_dirty(pmd)) + flags |= PM_SOFT_DIRTY; VM_BUG_ON(!is_pmd_migration_entry(pmd)); page = migration_entry_to_page(entry); } -- 2.14.2