From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 61F0C6B0281 for ; Sun, 29 Jan 2017 12:39:12 -0500 (EST) Received: by mail-pf0-f199.google.com with SMTP id 201so426143337pfw.5 for ; Sun, 29 Jan 2017 09:39:12 -0800 (PST) Received: from mga05.intel.com (mga05.intel.com. [192.55.52.43]) by mx.google.com with ESMTPS id 32si10216990plf.34.2017.01.29.09.39.11 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 29 Jan 2017 09:39:11 -0800 (PST) From: "Kirill A. Shutemov" Subject: [PATCHv3 05/12] mm, rmap: check all VMAs that PTE-mapped THP can be part of Date: Sun, 29 Jan 2017 20:38:51 +0300 Message-Id: <20170129173858.45174-6-kirill.shutemov@linux.intel.com> In-Reply-To: <20170129173858.45174-1-kirill.shutemov@linux.intel.com> References: <20170129173858.45174-1-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Arcangeli , Hugh Dickins , Rik van Riel , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Current rmap code can miss a VMA that maps PTE-mapped THP if the first suppage of the THP was unmapped from the VMA. We need to walk rmap for the whole range of offsets that THP covers, not only the first one. vma_address() also need to be corrected to check the range instead of the first subpage. Signed-off-by: Kirill A. Shutemov Acked-by: Hillf Danton --- mm/internal.h | 9 ++++++--- mm/rmap.c | 16 ++++++++++------ 2 files changed, 16 insertions(+), 9 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 03763f5c42c5..1f90c65df7fb 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -333,12 +333,15 @@ __vma_address(struct page *page, struct vm_area_struct *vma) static inline unsigned long vma_address(struct page *page, struct vm_area_struct *vma) { - unsigned long address = __vma_address(page, vma); + unsigned long start, end; + + start = __vma_address(page, vma); + end = start + PAGE_SIZE * (hpage_nr_pages(page) - 1); /* page should be within @vma mapping range */ - VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); + VM_BUG_ON_VMA(end < vma->vm_start || start >= vma->vm_end, vma); - return address; + return max(start, vma->vm_start); } #else /* !CONFIG_MMU */ diff --git a/mm/rmap.c b/mm/rmap.c index 0dff8accd629..c4bad599cc7b 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1757,7 +1757,7 @@ static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc, bool locked) { struct anon_vma *anon_vma; - pgoff_t pgoff; + pgoff_t pgoff_start, pgoff_end; struct anon_vma_chain *avc; int ret = SWAP_AGAIN; @@ -1771,8 +1771,10 @@ static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc, if (!anon_vma) return ret; - pgoff = page_to_pgoff(page); - anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) { + pgoff_start = page_to_pgoff(page); + pgoff_end = pgoff_start + hpage_nr_pages(page) - 1; + anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, + pgoff_start, pgoff_end) { struct vm_area_struct *vma = avc->vma; unsigned long address = vma_address(page, vma); @@ -1810,7 +1812,7 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc, bool locked) { struct address_space *mapping = page_mapping(page); - pgoff_t pgoff; + pgoff_t pgoff_start, pgoff_end; struct vm_area_struct *vma; int ret = SWAP_AGAIN; @@ -1825,10 +1827,12 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc, if (!mapping) return ret; - pgoff = page_to_pgoff(page); + pgoff_start = page_to_pgoff(page); + pgoff_end = pgoff_start + hpage_nr_pages(page) - 1; if (!locked) i_mmap_lock_read(mapping); - vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { + vma_interval_tree_foreach(vma, &mapping->i_mmap, + pgoff_start, pgoff_end) { unsigned long address = vma_address(page, vma); cond_resched(); -- 2.11.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org