mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: Andrey Vagin <avagin@openvz.org>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
	Cyrill Gorcunov <gorcunov@openvz.org>,
	criu@openvz.org, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	Pavel Emelyanov <xemul@parallels.com>,
	Borislav Petkov <bp@suse.de>, Wen Congyang <wency@cn.fujitsu.com>
Subject: Re: [PATCH] mm: don't lose the SOFT_DIRTY flag on mprotect
Date: Wed, 29 Jan 2014 12:18:59 -0800	[thread overview]
Message-ID: <20140129121859.07da0df20daea6a1581e709a@linux-foundation.org> (raw)
In-Reply-To: <1391025899-25299-1-git-send-email-avagin@openvz.org>

On Thu, 30 Jan 2014 00:04:59 +0400 Andrey Vagin <avagin@openvz.org> wrote:

> The SOFT_DIRTY bit shows that the content of memory was changed
> after a defined point in the past. mprotect() doesn't change the
> content of memory, so it must not change the SOFT_DIRTY bit.
> 
> This patch does nothing with _PAGE_SWP_SOFT_DIRTY, becase pte_modify()
> is called only for present pages.

Standard complaint: when fixing a bug, please describe the end-user
visible effects of that bug.

afaict the effects are minor: snapshotting will save/copy more pages
than it needs to, but there will be no malfunction.  Hence a -stable
backport is unneeded.  Agree?



  reply	other threads:[~2014-01-29 20:19 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-29 20:04 Andrey Vagin
2014-01-29 20:18 ` Andrew Morton [this message]
2014-01-29 20:48   ` Andrew Vagin

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=20140129121859.07da0df20daea6a1581e709a@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=avagin@openvz.org \
    --cc=bp@suse.de \
    --cc=criu@openvz.org \
    --cc=gorcunov@openvz.org \
    --cc=hpa@zytor.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=wency@cn.fujitsu.com \
    --cc=x86@kernel.org \
    --cc=xemul@parallels.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

Powered by JetHome