Re: [PATCH 0/6][v3][lxc] Link LXC with USERCR

[Sukadev Bhattiprolu <sukadev-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>]

Cedric Le Goater [clg-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org] wrote:
> Hello Suka,
>
> On 04/01/2010 03:55 AM, Sukadev Bhattiprolu wrote:
>
>> Resending patches after fixing whitespace damage and the typo in
>> configure.ac. Add a section to patch-0 (below) to describe the
>> kernel build (commit-id, config tokens etc).
>
> we plan to mergepatch 2,3,4 in lxc mainline real soon, maybe not as such,
> but they won't be in the way anymore. For the moment, please keep 1,5,6 but
> make it one patch. no need to resend them in a scattered mode.

Ok. Can you apply 1,5,6 to a separate branch, say usercr-v1, so its easier
for others to pull ? When I have some major changes I can resend the patches
merged up to latest LXC and maybe we can then have usercr-v2 and so on.

>
>> 1. Build C/R-enabled Linux kernel
>>
>> 	$ cd /root
>>
>> 	$ git-clone  git://www.linux-cr.org/pub/git/linux-cr.git linux-cr
>>
>> 	$ cd linux-cr
>>
>> 	$ git-checkout ckpt-v20-dev
>>
>> 		I tested with commit 3522c57a9ec6f08a129a78322318abcb4467db28
>> 		as HEAD.
>
> we need to work on a better delivery scheme. I don't think a commit id is not
> the most efficient way to dialog when integrating components. We'd rather use
> a tarball or a patch on an identified kernel.

Hmm, I thought we could just make a branch on the commit-id and apply
any additional patches there and build.

I will base it on a closed-release next time like ckpt-v20-rc1 rather
than an open one like ckpt-v20-dev.

>
>> 	# After every reboot, ensure '-o newinstance' mount option to /dev/pts
>> 	  works (see Documentation/filesystems/devpts.txt for details). In
>> 	  short, run following commands on each reboot:
>>
>> 		$ rm /dev/ptmx
>>
>> 		$ ln -s pts/ptmx /dev/ptmx
>>
>> 		$ chmod 666 /dev/pts/ptmx
>
> can not it be integrated in lxc as a patch ?

This is an OS boot/setup issue, so its probably easier to put this in
/etc/rc.local or some such file.

>
>> 1. Build USERCR
>>
>> 	$ cd /root
>>
>> 	$ git-clone git://git.ncl.cs.columbia.edu/pub/git/user-cr.git user-cr
>>
>> 	$ cd user-cr
>>
>> 	$ git-checkout ckpt-v20-dev
>>
>> 	  	Tested with commit e275f77e4a82d228c1df14dbeb691342e32cdac2
>> 		as HEAD.
>
> IMO, tarball and version would be better.
>
>> 	# Apply following two patches:
>>
>> 	https://lists.linux-foundation.org/pipermail/containers/2010-March/024037.html
>> 	https://lists.linux-foundation.org/pipermail/containers/2010-March/024038.html
>
> do you plan to merge them ? if not why ?

Yes. They have been merged now. There maybe a few days delay between my
posting and the merging and I pointed to the link in case someone wants
to try before they are merged.
>
>> 	$ KERNELSRC=/root/linux-cr make
>>
>> 		Build USERCR by pointing to corresponding kernel-source.
>> 		This should create restart.o and checkpoint.o needed by LXC.
>>
>> 		I did not need to, but you may need to compile checkpoint.o
>> 		and restart.o with -fPIC compiler option.
>
> this needs to be worked out also to be more developer friendly.
>
> if compilation is a pain, we will put some effort into it once but be reluctant to
> do it twice. That's what happened to me this time. I didn't compile and let daniel
> spent nearly one day to make your environment work ...

Agree and am planning to write up these instructions in a wiki and
hopefully we can simplify the process over time. I tested several times
on my environment before posting :-) 

BTW, Is fPIC needed always ?

Sukadev