From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Hansen Subject: Re: Banning checkpoint (was: Re: What can OpenVZ do?) Date: Mon, 23 Feb 2009 21:11:25 -0800 Message-ID: <1235452285.26788.226.camel@nimitz> References: <20090217222319.GA10546@elte.hu> <1234909849.4816.9.camel@nimitz> <20090218003217.GB25856@elte.hu> <1234917639.4816.12.camel@nimitz> <20090218051123.GA9367@x200.localdomain> <20090218181644.GD19995@elte.hu> <1234992447.26788.12.camel@nimitz> <20090218231545.GA17524@elte.hu> <20090219190637.GA4846@x200.localdomain> <1235070714.26788.56.camel@nimitz> <20090224044752.GB3202@x200.localdomain> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090224044752.GB3202-2ev+ksY9ol182hYKe6nXyg@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alexey Dobriyan Cc: Ingo Molnar , Nathan Lynch , linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, mpm-VDJrAJ4Gl5ZBDgjK7y7TUQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, Andrew Morton , torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, xemul-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org List-Id: linux-api@vger.kernel.org On Tue, 2009-02-24 at 07:47 +0300, Alexey Dobriyan wrote: > > I think what I posted is a decent compromise. It gets you those > > warnings at runtime and is a one-way trip for any given process. But, > > it does detect in certain cases (fork() and unshare(FILES)) when it is > > safe to make the trip back to the "I'm checkpointable" state again. > > "Checkpointable" is not even per-process property. > > Imagine, set of SAs (struct xfrm_state) and SPDs (struct xfrm_policy). > They are a) per-netns, b) persistent. > > You can hook into socketcalls to mark process as uncheckpointable, > but since SAs and SPDs are persistent, original process already exited. > You're going to walk every process with same netns as SA adder and mark > it as uncheckpointable. Definitely doable, but ugly, isn't it? > > Same for iptable rules. > > "Checkpointable" is container property, OK? Ideally, I completely agree. But, we don't currently have a concept of a true container in the kernel. Do you have any suggestions for any current objects that we could use in its place for a while? -- Dave -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html