Subject: Re: [RFC v6][PATCH 0/9] Kernel based checkpoint/restart
From: Dave Hansen <dave@linux.vnet.ibm.com>
To: Cedric Le Goater <clg@fr.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, jeremy@goop.org, arnd@arndb.de,
       containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
       linux-mm@kvack.org, Alexander Viro <viro@zeniv.linux.org.uk>,
       "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
       Andrey Mirkin <major@openvz.org>
In-Reply-To: <48F30315.1070909@fr.ibm.com>
References: <1223461197-11513-1-git-send-email-orenl@cs.columbia.edu>
	 <20081009124658.GE2952@elte.hu> <1223557122.11830.14.camel@nimitz>
	 <20081009131701.GA21112@elte.hu> <1223559246.11830.23.camel@nimitz>
	 <20081009134415.GA12135@elte.hu> <1223571036.11830.32.camel@nimitz>
	 <20081010153951.GD28977@elte.hu>  <48F30315.1070909@fr.ibm.com>
Content-Type: text/plain
Date: Mon, 13 Oct 2008 09:43:43 -0700
Message-Id: <1223916223.29877.14.camel@nimitz>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 858
Lines: 22

On Mon, 2008-10-13 at 10:13 +0200, Cedric Le Goater wrote:
> hmm, that's rather complex, because we have to take into account the 
> kernel stack, no ? This is what Andrey was trying to solve in his patchset 
> back in September :
> 
>         http://lkml.org/lkml/2008/9/3/96
> 
> the restart phase simulates a clone and switch_to to (not) restore the kernel 
> stack. right ? 

Do we ever have to worry about the kernel stack if we simply say that
tasks have to be *in* userspace when we checkpoint them.  If a task is
in an uninterruptable wait state, I'm not sure it's safe to checkpoint
it anyway.

-- Dave

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/