linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Michal Hocko <mhocko@kernel.org>
To: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>,
	willy@infradead.org, akpm@linux-foundation.org,
	peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
	alexander.shishkin@linux.intel.com, jolsa@redhat.com,
	namhyung@kernel.org, tglx@linutronix.de, hpa@zytor.com,
	linux-mm@kvack.org, x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC v3 PATCH 5/5] x86: check VM_DEAD flag in page fault
Date: Mon, 2 Jul 2018 15:37:33 +0200	[thread overview]
Message-ID: <20180702133733.GU19043@dhcp22.suse.cz> (raw)
In-Reply-To: <e6f8d0e2-48c1-f610-c00b-d05d4bd0d9eb@linux.vnet.ibm.com>

On Mon 02-07-18 15:33:11, Laurent Dufour wrote:
> 
> 
> On 02/07/2018 14:45, Michal Hocko wrote:
> > On Mon 02-07-18 14:26:09, Laurent Dufour wrote:
> >> On 02/07/2018 14:15, Michal Hocko wrote:
[...]
> >>> We already do have a model for that. Have a look at MMF_UNSTABLE.
> >>
> >> MMF_UNSTABLE is a mm's flag, here this is a VMA's flag which is checked.
> > 
> > Yeah, and we have the VMA ready for all places where we do check the
> > flag. check_stable_address_space can be made to get vma rather than mm.
> 
> Yeah, this would have been more efficient to check that flag at the beginning
> of the page fault handler rather than the end, but this way it will be easier
> to handle the speculative page fault too ;)

The thing is that it doesn't really need to be called earlier. You are
not risking data corruption on file backed mappings.

-- 
Michal Hocko
SUSE Labs

  reply	other threads:[~2018-07-02 13:37 UTC|newest]

Thread overview: 48+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-29 22:39 [RFC v3 PATCH 0/5] mm: zap pages with read mmap_sem in munmap for large mapping Yang Shi
2018-06-29 22:39 ` [RFC v3 PATCH 1/5] uprobes: make vma_has_uprobes non-static Yang Shi
2018-06-29 22:39 ` [RFC v3 PATCH 2/5] mm: introduce VM_DEAD flag Yang Shi
2018-07-02 13:40   ` Michal Hocko
2018-06-29 22:39 ` [RFC v3 PATCH 3/5] mm: refactor do_munmap() to extract the common part Yang Shi
2018-07-02 13:42   ` Michal Hocko
2018-07-02 16:59     ` Yang Shi
2018-07-02 17:58       ` Michal Hocko
2018-07-02 18:02         ` Yang Shi
2018-06-29 22:39 ` [RFC v3 PATCH 4/5] mm: mmap: zap pages with read mmap_sem for large mapping Yang Shi
2018-06-30  1:28   ` Andrew Morton
2018-06-30  2:10     ` Yang Shi
2018-06-30  1:35   ` Andrew Morton
2018-06-30  2:28     ` Yang Shi
2018-06-30  3:15       ` Andrew Morton
2018-06-30  4:26         ` Yang Shi
2018-07-03  0:01           ` Yang Shi
2018-07-02 14:05         ` Michal Hocko
2018-07-02 20:48           ` Andrew Morton
2018-07-03  6:09             ` Michal Hocko
2018-07-03 16:53               ` Yang Shi
2018-07-03 18:22               ` Yang Shi
2018-07-04  8:13                 ` Michal Hocko
2018-07-02 12:33   ` Kirill A. Shutemov
2018-07-02 12:49     ` Michal Hocko
2018-07-03  8:12       ` Kirill A. Shutemov
2018-07-03  8:27         ` Michal Hocko
2018-07-03  9:19           ` Kirill A. Shutemov
2018-07-03 11:34             ` Michal Hocko
2018-07-03 12:14               ` Kirill A. Shutemov
2018-07-03 17:00                 ` Yang Shi
2018-07-02 17:19     ` Yang Shi
2018-07-03  8:07       ` Kirill A. Shutemov
2018-07-02 13:53   ` Michal Hocko
2018-07-02 17:07     ` Yang Shi
2018-06-29 22:39 ` [RFC v3 PATCH 5/5] x86: check VM_DEAD flag in page fault Yang Shi
2018-07-02  8:45   ` Laurent Dufour
2018-07-02 12:15     ` Michal Hocko
2018-07-02 12:26       ` Laurent Dufour
2018-07-02 12:45         ` Michal Hocko
2018-07-02 13:33           ` Laurent Dufour
2018-07-02 13:37             ` Michal Hocko [this message]
2018-07-02 17:24               ` Yang Shi
2018-07-02 17:57                 ` Michal Hocko
2018-07-02 18:10                   ` Yang Shi
2018-07-03  6:17                     ` Michal Hocko
2018-07-03 16:50                       ` Yang Shi
2018-07-02 13:39 ` [RFC v3 PATCH 0/5] mm: zap pages with read mmap_sem in munmap for large mapping Michal Hocko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180702133733.GU19043@dhcp22.suse.cz \
    --to=mhocko@kernel.org \
    --cc=acme@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=jolsa@redhat.com \
    --cc=ldufour@linux.vnet.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=willy@infradead.org \
    --cc=x86@kernel.org \
    --cc=yang.shi@linux.alibaba.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).