From: ebiederm@xmission.com (Eric W. Biederman)
To: Greg KH <greg@kroah.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>,
LSM <linux-security-module@vger.kernel.org>,
James Morris <jmorris@namei.org>,
Kees Cook <kees.cook@canonical.com>,
containers@lists.linux-foundation.org,
kernel list <linux-kernel@vger.kernel.org>,
Alexey Dobriyan <adobriyan@gmail.com>,
Michael Kerrisk <michael.kerrisk@gmail.com>
Subject: Re: [RFC 1/5] user namespaces: Add a user_namespace as creator/owner of uts_namespace
Date: Fri, 17 Dec 2010 22:32:52 -0800 [thread overview]
Message-ID: <m1vd2rlhez.fsf@fess.ebiederm.org> (raw)
In-Reply-To: <20101217231527.GA21227@kroah.com> (Greg KH's message of "Fri, 17 Dec 2010 15:15:27 -0800")
Greg KH <greg@kroah.com> writes:
> On Fri, Dec 17, 2010 at 12:40:11PM -0800, Eric W. Biederman wrote:
>> Greg KH <greg@kroah.com> writes:
>>
>> >> There are also major benefits to have the version of something that is
>> >> never freed never going away, because it means you can just reference it
>> >> in code. So while I would be happy to say this is special don't use a
>> >> kref and roll the reference counting logic by hand, we aren't
>> >> dynamically allocating init_uts_ns any time soon.
>> >
>> > Why have a reference count at all if it's not needed or used here?
>>
>> We have to reference count every other uts namespace.
>
> Ok, that makes sense, then also please dynamically create this one, do
> not create a static kref.
Nope. It's a bad idea. It messes up the kernel bootstrap if you do
that, and it makes this one structure different from every other
structure init_task uses.
Eric
next prev parent reply other threads:[~2010-12-18 6:33 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-17 15:22 [RFC 0/5] user namespaces: start clamping down Serge E. Hallyn
2010-12-17 15:24 ` [RFC 1/5] user namespaces: Add a user_namespace as creator/owner of uts_namespace Serge E. Hallyn
2010-12-17 15:25 ` [RFC 2/5] user namespaces: make capabilities relative to the user namespace Serge E. Hallyn
[not found] ` <20101217152547.GB11162-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 15:26 ` [RFC 3/5] user namespaces: allow sethostname in a container Serge E. Hallyn
2010-12-17 15:26 ` Serge E. Hallyn
[not found] ` <20101217152625.GC11162-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 15:26 ` [RFC 4/5] user namespaces: allow killing tasks in your own or child userns Serge E. Hallyn
2010-12-17 15:26 ` Serge E. Hallyn
[not found] ` <20101217152659.GD11162-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 15:27 ` [RFC 5/5] user namespaces: Allow ptrace from non-init user namespaces Serge E. Hallyn
2010-12-17 19:31 ` [RFC 4/5] user namespaces: allow killing tasks in your own or child userns Eric W. Biederman
2010-12-17 15:27 ` [RFC 5/5] user namespaces: Allow ptrace from non-init user namespaces Serge E. Hallyn
2010-12-17 19:45 ` Eric W. Biederman
[not found] ` <m1hbecqj2q.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2010-12-17 20:04 ` Serge Hallyn
2011-01-01 4:47 ` Serge E. Hallyn
2010-12-17 20:04 ` Serge Hallyn
2011-01-01 4:47 ` Serge E. Hallyn
[not found] ` <20101217152737.GE11162-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 19:45 ` Eric W. Biederman
2010-12-17 19:31 ` [RFC 4/5] user namespaces: allow killing tasks in your own or child userns Eric W. Biederman
[not found] ` <m14oacryar.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2010-12-17 20:09 ` Serge E. Hallyn
2010-12-17 20:09 ` Serge E. Hallyn
[not found] ` <20101217200903.GA15528-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 20:17 ` Eric W. Biederman
2010-12-17 20:17 ` Eric W. Biederman
2010-12-17 20:22 ` Serge E. Hallyn
[not found] ` <m1d3p0qhl5.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2010-12-17 20:22 ` Serge E. Hallyn
2011-01-01 4:45 ` Serge E. Hallyn
2011-01-01 4:45 ` Serge E. Hallyn
[not found] ` <20110101044522.GA26476-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2011-01-01 23:10 ` Eric W. Biederman
2011-01-01 23:10 ` Eric W. Biederman
[not found] ` <m1zkrkuso4.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2011-01-02 14:39 ` Serge E. Hallyn
2011-01-02 14:39 ` Serge E. Hallyn
2010-12-17 15:56 ` [RFC 1/5] user namespaces: Add a user_namespace as creator/owner of uts_namespace Alexey Dobriyan
[not found] ` <AANLkTinPBAPjeEdhn21JN6zVpAKDHR9=3gszj84CyyNx-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2010-12-17 16:00 ` Alexey Dobriyan
2010-12-17 16:12 ` Serge Hallyn
2010-12-17 16:00 ` Alexey Dobriyan
[not found] ` <AANLkTik2ry7zbRMgiwhrXMYfQ4tr07BW0ODCNbKBMWmc-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2010-12-17 16:17 ` Serge Hallyn
2010-12-17 16:17 ` Serge Hallyn
2010-12-17 16:12 ` Serge Hallyn
[not found] ` <20101217152458.GA11162-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 15:25 ` [RFC 2/5] user namespaces: make capabilities relative to the user namespace Serge E. Hallyn
2010-12-17 15:56 ` [RFC 1/5] user namespaces: Add a user_namespace as creator/owner of uts_namespace Alexey Dobriyan
2010-12-17 17:31 ` Greg KH
2010-12-17 17:31 ` Greg KH
[not found] ` <20101217173125.GA29982-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2010-12-17 19:26 ` Eric W. Biederman
2010-12-17 19:46 ` Serge Hallyn
2010-12-17 19:26 ` Eric W. Biederman
2010-12-17 19:58 ` Greg KH
[not found] ` <20101217195829.GB1410-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2010-12-17 20:40 ` Eric W. Biederman
2010-12-17 20:40 ` Eric W. Biederman
[not found] ` <m1ipysm8us.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2010-12-17 23:15 ` Greg KH
2010-12-17 23:15 ` Greg KH
[not found] ` <20101217231527.GA21227-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2010-12-18 6:32 ` Eric W. Biederman
2010-12-18 6:32 ` Eric W. Biederman [this message]
2010-12-18 17:56 ` Greg KH
[not found] ` <m1vd2rlhez.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2010-12-18 17:56 ` Greg KH
[not found] ` <m18vzoryit.fsf-+imSwln9KH6u2/kzUuoCbdi2O/JbrIOy@public.gmane.org>
2010-12-17 19:58 ` Greg KH
2010-12-17 19:46 ` Serge Hallyn
2010-12-17 19:57 ` Greg KH
2010-12-17 19:57 ` Greg KH
[not found] ` <20101217152246.GA8221-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2010-12-17 15:24 ` Serge E. Hallyn
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=m1vd2rlhez.fsf@fess.ebiederm.org \
--to=ebiederm@xmission.com \
--cc=adobriyan@gmail.com \
--cc=containers@lists.linux-foundation.org \
--cc=greg@kroah.com \
--cc=jmorris@namei.org \
--cc=kees.cook@canonical.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=michael.kerrisk@gmail.com \
--cc=serge@hallyn.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.