From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman) Subject: Re: [RFC][PATCH 0/8][v2]: Enable multiple mounts of devpts Date: Thu, 21 Aug 2008 10:45:07 -0700 Message-ID: References: <20080821022126.GA29449@us.ibm.com> <48ACD6CB.5030706@zytor.com> <20080821031028.GB30205@us.ibm.com> <48ACDDC7.3000704@zytor.com> <48AD991F.9010906@fr.ibm.com> <48AD9A97.6000807@zytor.com> <48AD9DCD.3060306@fr.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <48AD9DCD.3060306-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org> (Cedric Le Goater's message of "Thu, 21 Aug 2008 18:54:37 +0200") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Cedric Le Goater Cc: kyle-hoO6YkzgTuCM0SS3m2neIg@public.gmane.org, bastian-yyjItF7Rl6lg9hUCZPvPmw@public.gmane.org, "H. Peter Anvin" , containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org, alan-qBU/x9rampVanCEyBjwyrvXRex20P6io@public.gmane.org, xemul-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org List-Id: containers.vger.kernel.org Cedric Le Goater writes: > H. Peter Anvin wrote: >> Cedric Le Goater wrote: >>>>> >>>> I suggest "newinstance", but "newns" works, too. >>> >>> Could we also use this mount option to 'unshare' a new posix message >>> queue namespace ? >> >> Sorry, I fail to see the connection with devpts here? Are you >> suggesting using the same option for another filesystem (if so, which)? > > yes. the posix message queues are also using a single superblock filesystem. > > If we want isolate them (for container needs for example), we also need to > create a new sb. The patchset I have uses a clone flag but using a mount > 'newns' really sounds like a better idea. Let's call it newinstance if we are going to use the same option for devpts. We can update "current->nsproxy->mqueuens" when the newinstance flag is passed and otherwise we can mount whatever is the current mqueue filesystem for the process. That should be simple and just work. Eric