From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753892Ab3C2FaY (ORCPT ); Fri, 29 Mar 2013 01:30:24 -0400 Received: from mail-lb0-f173.google.com ([209.85.217.173]:43695 "EHLO mail-lb0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752165Ab3C2FaX (ORCPT ); Fri, 29 Mar 2013 01:30:23 -0400 Message-ID: <515526EA.3090807@openvz.org> Date: Fri, 29 Mar 2013 09:30:18 +0400 From: Konstantin Khlebnikov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130119 Firefox/10.0.11esrpre Iceape/2.7.12 MIME-Version: 1.0 To: Naoya Horiguchi CC: Andrew Morton , Mel Gorman , Hugh Dickins , Rik van Riel , KOSAKI Motohiro , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] hugetlbfs: stop setting VM_DONTDUMP in initializing vma(VM_HUGETLB) References: <1364485358-8745-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1364485358-8745-2-git-send-email-n-horiguchi@ah.jp.nec.com> <515477D4.1060206@openvz.org> <1364495358-2gnie765-mutt-n-horiguchi@ah.jp.nec.com> In-Reply-To: <1364495358-2gnie765-mutt-n-horiguchi@ah.jp.nec.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Naoya Horiguchi wrote: > On Thu, Mar 28, 2013 at 09:03:16PM +0400, Konstantin Khlebnikov wrote: >> Naoya Horiguchi wrote: >>> Currently we fail to include any data on hugepages into coredump, >>> because VM_DONTDUMP is set on hugetlbfs's vma. This behavior was recently >>> introduced by commit 314e51b98 "mm: kill vma flag VM_RESERVED and >>> mm->reserved_vm counter". This looks to me a serious regression, >>> so let's fix it. >> >> That was introduced in my patch? Really? >> Here was VM_RESERVED and it had the same effect as VM_DONTDUMP. At least I thought so. > > vma_dump_size() does like this (the diff is the one in 314e51b98): > > static unsigned long vma_dump_size(struct vm_area_struct *vma, > unsigned long mm_flags) > { > #define FILTER(type) (mm_flags& (1UL<< MMF_DUMP_##type)) > > /* always dump the vdso and vsyscall sections */ > if (always_dump_vma(vma)) > goto whole; > > if (vma->vm_flags& VM_DONTDUMP) > return 0; > > /* Hugetlb memory check */ > if (vma->vm_flags& VM_HUGETLB) { > if ((vma->vm_flags& VM_SHARED)&& FILTER(HUGETLB_SHARED)) > goto whole; > if (!(vma->vm_flags& VM_SHARED)&& FILTER(HUGETLB_PRIVATE)) > goto whole; > } > > /* Do not dump I/O mapped devices or special mappings */ > - if (vma->vm_flags& (VM_IO | VM_RESERVED)) > + if (vma->vm_flags& VM_IO) > return 0; > > We have hugetlb memory check after VM_DONTDUMP check, so the following > changed the behavior. Ok, I missed this in my patch. > > --- a/fs/hugetlbfs/inode.c > +++ b/fs/hugetlbfs/inode.c > @@ -110,7 +110,7 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) > * way when do_mmap_pgoff unwinds (may be important on powerpc > * and ia64). > */ > - vma->vm_flags |= VM_HUGETLB | VM_RESERVED; > + vma->vm_flags |= VM_HUGETLB | VM_DONTEXPAND | VM_DONTDUMP; > vma->vm_ops =&hugetlb_vm_ops; > > if (vma->vm_pgoff& (~huge_page_mask(h)>> PAGE_SHIFT)) > > I think we don't have to set VM_DONTDUMP on hugetlbfs's vma. Acked-by: Konstantin Khlebnikov > > Thanks, > Naoya From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx119.postini.com [74.125.245.119]) by kanga.kvack.org (Postfix) with SMTP id DCFFE6B0002 for ; Fri, 29 Mar 2013 01:30:23 -0400 (EDT) Received: by mail-lb0-f177.google.com with SMTP id r10so68992lbi.36 for ; Thu, 28 Mar 2013 22:30:21 -0700 (PDT) Message-ID: <515526EA.3090807@openvz.org> Date: Fri, 29 Mar 2013 09:30:18 +0400 From: Konstantin Khlebnikov MIME-Version: 1.0 Subject: Re: [PATCH 1/2] hugetlbfs: stop setting VM_DONTDUMP in initializing vma(VM_HUGETLB) References: <1364485358-8745-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1364485358-8745-2-git-send-email-n-horiguchi@ah.jp.nec.com> <515477D4.1060206@openvz.org> <1364495358-2gnie765-mutt-n-horiguchi@ah.jp.nec.com> In-Reply-To: <1364495358-2gnie765-mutt-n-horiguchi@ah.jp.nec.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Naoya Horiguchi Cc: Andrew Morton , Mel Gorman , Hugh Dickins , Rik van Riel , KOSAKI Motohiro , linux-mm@kvack.org, linux-kernel@vger.kernel.org Naoya Horiguchi wrote: > On Thu, Mar 28, 2013 at 09:03:16PM +0400, Konstantin Khlebnikov wrote: >> Naoya Horiguchi wrote: >>> Currently we fail to include any data on hugepages into coredump, >>> because VM_DONTDUMP is set on hugetlbfs's vma. This behavior was recently >>> introduced by commit 314e51b98 "mm: kill vma flag VM_RESERVED and >>> mm->reserved_vm counter". This looks to me a serious regression, >>> so let's fix it. >> >> That was introduced in my patch? Really? >> Here was VM_RESERVED and it had the same effect as VM_DONTDUMP. At least I thought so. > > vma_dump_size() does like this (the diff is the one in 314e51b98): > > static unsigned long vma_dump_size(struct vm_area_struct *vma, > unsigned long mm_flags) > { > #define FILTER(type) (mm_flags& (1UL<< MMF_DUMP_##type)) > > /* always dump the vdso and vsyscall sections */ > if (always_dump_vma(vma)) > goto whole; > > if (vma->vm_flags& VM_DONTDUMP) > return 0; > > /* Hugetlb memory check */ > if (vma->vm_flags& VM_HUGETLB) { > if ((vma->vm_flags& VM_SHARED)&& FILTER(HUGETLB_SHARED)) > goto whole; > if (!(vma->vm_flags& VM_SHARED)&& FILTER(HUGETLB_PRIVATE)) > goto whole; > } > > /* Do not dump I/O mapped devices or special mappings */ > - if (vma->vm_flags& (VM_IO | VM_RESERVED)) > + if (vma->vm_flags& VM_IO) > return 0; > > We have hugetlb memory check after VM_DONTDUMP check, so the following > changed the behavior. Ok, I missed this in my patch. > > --- a/fs/hugetlbfs/inode.c > +++ b/fs/hugetlbfs/inode.c > @@ -110,7 +110,7 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) > * way when do_mmap_pgoff unwinds (may be important on powerpc > * and ia64). > */ > - vma->vm_flags |= VM_HUGETLB | VM_RESERVED; > + vma->vm_flags |= VM_HUGETLB | VM_DONTEXPAND | VM_DONTDUMP; > vma->vm_ops =&hugetlb_vm_ops; > > if (vma->vm_pgoff& (~huge_page_mask(h)>> PAGE_SHIFT)) > > I think we don't have to set VM_DONTDUMP on hugetlbfs's vma. Acked-by: Konstantin Khlebnikov > > Thanks, > Naoya -- 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