From: Andrei Vagin <avagin@virtuozzo.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>,
agruenba@redhat.com, keescook@chromium.org,
linux-api@vger.kernel.org, linux-kernel@vger.kernel.org,
viro@zeniv.linux.org.uk, oleg@redhat.com, paul@paul-moore.com,
ebiederm@xmission.com, avagin@openvz.org,
linux-fsdevel@vger.kernel.org, mtk.manpages@gmail.com,
luto@amacapital.net, mingo@kernel.org, serge@hallyn.com
Subject: Re: [PATCH RESEND 2/2] pidns: Expose task pid_ns_for_children to userspace
Date: Thu, 30 Mar 2017 18:04:10 -0700 [thread overview]
Message-ID: <20170331010409.GA22895@outlook.office365.com> (raw)
In-Reply-To: <20170330150520.1bdf20e599ff464bda0776b9@linux-foundation.org>
On Thu, Mar 30, 2017 at 03:05:20PM -0700, Andrew Morton wrote:
> On Thu, 30 Mar 2017 13:27:59 +0300 Kirill Tkhai <ktkhai@virtuozzo.com> wrote:
>
> > pid_ns_for_children set by a task is known only to the task itself,
> > and it's impossible to identify it from outside.
> >
> > It's a big problem for checkpoint/restore software like CRIU,
> > because it can't correctly handle tasks, that do setns(CLONE_NEWPID)
> > in proccess of their work.
> >
> > This patch solves the problem, and it exposes pid_ns_for_children
> > to ns directory in standard way with the name "pid_for_children":
> >
> > ~# ls /proc/5531/ns -l | grep pid
> > lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid -> pid:[4026531836]
> > lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid_for_children -> pid:[4026532286]
> >
> > --- a/fs/proc/namespaces.c
> > +++ b/fs/proc/namespaces.c
> > @@ -23,6 +23,7 @@ static const struct proc_ns_operations *ns_entries[] = {
> > #endif
> > #ifdef CONFIG_PID_NS
> > &pidns_operations,
> > + &pidns_for_children_operations,
> > #endif
>
> This interface should be documented somewhere under Documentation/.
> But I can't immediately find where the /proc/pid/ns/ pseudo-files are
> documented...
I know that they are documented in man7/namespaces.7
https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/man7/namespaces.7#n187
>
>
next prev parent reply other threads:[~2017-03-31 1:04 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-03-30 10:27 [PATCH RESEND 0/2] Expose task pid_ns_for_children to userspace Kirill Tkhai
2017-03-30 10:27 ` [PATCH RESEND 1/2] ns: Allow ns_entries to have custom symlink content Kirill Tkhai
[not found] ` <149086931397.4388.9604947335273204415.stgit-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2017-03-30 10:27 ` [PATCH RESEND 2/2] pidns: Expose task pid_ns_for_children to userspace Kirill Tkhai
[not found] ` <149086967937.4388.471494976517194744.stgit-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org>
2017-03-30 22:05 ` Andrew Morton
2017-03-31 1:04 ` Andrei Vagin [this message]
[not found] ` <20170331010409.GA22895-1ViLX0X+lBJGNQ1M2rI3KwRV3xvJKrda@public.gmane.org>
2017-03-31 9:45 ` Kirill Tkhai
[not found] ` <0825f166-6f20-59a9-45a9-5ffe9009150e-5HdwGun5lf+gSpxsJD1C4w@public.gmane.org>
2017-03-31 15:06 ` Kees Cook
[not found] ` <CAGXu5jJYTrOB1A0V9V8NOtLUF_D52RwtqFUcfsCiC-Jm3Z5G2w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2017-03-31 15:25 ` Kirill Tkhai
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=20170331010409.GA22895@outlook.office365.com \
--to=avagin@virtuozzo.com \
--cc=agruenba@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=avagin@openvz.org \
--cc=ebiederm@xmission.com \
--cc=keescook@chromium.org \
--cc=ktkhai@virtuozzo.com \
--cc=linux-api@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=mingo@kernel.org \
--cc=mtk.manpages@gmail.com \
--cc=oleg@redhat.com \
--cc=paul@paul-moore.com \
--cc=serge@hallyn.com \
--cc=viro@zeniv.linux.org.uk \
/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).