From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e35.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id m56HVlGg007115 for ; Fri, 6 Jun 2008 13:31:47 -0400 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m56HVeGD085052 for ; Fri, 6 Jun 2008 11:31:40 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m56HVdI4026120 for ; Fri, 6 Jun 2008 11:31:39 -0600 Subject: [RFC][PATCH 2/2] fix large pages in pagemap From: Dave Hansen Date: Fri, 06 Jun 2008 10:31:38 -0700 References: <20080606173137.24513039@kernel> In-Reply-To: <20080606173137.24513039@kernel> Message-Id: <20080606173138.9BFE6272@kernel> Sender: owner-linux-mm@kvack.org Return-Path: To: Hans Rosenfeld Cc: Matt Mackall , linux-mm@kvack.org, Dave Hansen List-ID: We were walking right into huge page areas in the pagemap walker, and calling the pmds pmd_bad() and clearing them. That leaked huge pages. Bad. This patch at least works around that for now. It ignores huge pages in the pagemap walker for the time being, and won't leak those pages. Signed-off-by: Dave Hansen --- linux-2.6.git-dave/fs/proc/task_mmu.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff -puN fs/proc/task_mmu.c~fix-large-pages-in-pagemap fs/proc/task_mmu.c --- linux-2.6.git/fs/proc/task_mmu.c~fix-large-pages-in-pagemap 2008-06-06 09:44:45.000000000 -0700 +++ linux-2.6.git-dave/fs/proc/task_mmu.c 2008-06-06 09:48:44.000000000 -0700 @@ -567,12 +567,19 @@ static u64 swap_pte_to_pagemap_entry(pte static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { + struct vm_area_struct *vma = NULL; struct pagemapread *pm = walk->private; pte_t *pte; int err = 0; for (; addr != end; addr += PAGE_SIZE) { u64 pfn = PM_NOT_PRESENT; + + if (!vma || addr >= vma->vm_end) + vma = find_vma(walk->mm, addr); + if (vma && is_vm_hugetlb_page(vma)) { + goto add: + pte = pte_offset_map(pmd, addr); if (is_swap_pte(*pte)) pfn = PM_PFRAME(swap_pte_to_pagemap_entry(*pte)) @@ -582,6 +589,7 @@ static int pagemap_pte_range(pmd_t *pmd, | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT; /* unmap so we're not in atomic when we copy to userspace */ pte_unmap(pte); + add: err = add_to_pagemap(addr, pfn, pm); if (err) return err; diff -puN mm/pagewalk.c~fix-large-pages-in-pagemap mm/pagewalk.c _ -- 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