[lxc-devel] [PATCH] Support MS_SHARED / - issues calling MAKEDEV

[Alexander Vladimirov]

2013/1/9 Michael H. Warfield <mhw at wittsend.com>:
> On Tue, 2013-01-08 at 15:40 -0500, Michael H. Warfield wrote:
>> On Wed, 2013-01-09 at 04:31 +0800, Alexander Vladimirov wrote:
>> > Well, properly placed hook could do all the things MAKEDEV supposed to do.
>>
>> And would give us the flexibility to worry about things like serial
>> devices or some USB devices or a few other things that would ordinarily
>> be populated by udev but don't vary over the life of the container.
>>
>> > 2013/1/9 Serge Hallyn <serge.hallyn at canonical.com>:
>> > > Quoting Michael H. Warfield (mhw at WittsEnd.com):
>> > >> More on the MAKEDEV debacle...
>> > > ...
>> > >> This whole thing with MAKEDEV is looking more and more like a morass
>> > >> with no way to cleanly resolve it.
>> > >
>> > > It sounds like consensus is it should be dropped from staging?
>
>> +1 for dropping the call to MAKEDEV, yeah.
>
> Looking at the sources now, removing run_makedev() and the call to is is
> pretty trivial.  I've already got a patch for that.
>
> WRT Alexander's suggestion for a hook...  I like that idea but a
> question comes up.  I've already got a patch for that hook,
> lxc.hook.autodev, as well and it's very close to where the
> lxc.hook.mount hooks is located only this one only gets invoked if
> autodev=1.  I'm still doing some testing but it looks like this could be
> done with the mount hook if we don't care for an isolated autodev one.
> OTOH, I can see some value in having a separate hook that only gets
> called if autodev is enabled.
>
> Next thought...  I dawns on me that many of these scripts could use some
> environment variables, such as the container name, the location of the
> rootfs, the location of the conf file, etc, etc.  That way, you could
> make the scripts a little more generic.  Problem is that we clear the
> environment and set "container=lxc" very early on in the process of
> starting up lxc-start.  Wouldn't that be just as effective if both where
> done just before execing the container and giving us the ability to pass
> environment variables to the hook scripts?  Maybe just AFTER
> lxc.hook.start?

Maybe we could just provide some environment configuration option in
container config to extend basic env with required values?

>> Regards,
>> Mike
>
> Regards,
> Mike
> --
> Michael H. Warfield (AI4NB) | (770) 985-6132 |  mhw at WittsEnd.com
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