Re: Where does /dev get mounted?

2017-10-30 Thread Brett Neumeier
On Oct 30, 2017 1:50 PM, "Laurent Bercot"  wrote:

But I do have a question: as documented, I find that when stage1's child
> process execs into stage2, there is a devtmpfs mounted at /dev. I don't
> understand where this happens! I see where the stage 1 script mounts a
> tmpfs at /run, but I don't see anything there, or in the initial s6
> scandir, that mounts /dev. What am I missing?
>

 If you created your stage 1 script with s6-linux-init-maker, and you
see nothing in your stage 1 that mounts /dev, it means that you told
s6-linux-init-maker that your kernel automounts /dev at boot time.

 So, your /dev is already mounted when the kernel spawns init. The
kernel option triggering that behaviour is named CONFIG_DEVTMPFS_MOUNT.


Thanks Laurent! I'm sure that's how it's set up, and I just forgot I'd
enabled that configuration setting.

Cheers,

Brett


Re: Where does /dev get mounted?

2017-10-30 Thread Brett Neumeier
Hi Colin,

Thanks for your reply! This isn't a distribution, though, and has no
initramfs -- it's a system I built myself, kind of like a Linux From
Scratch.

On Oct 30, 2017 1:49 PM, "Colin Booth"  wrote:

> On Mon, Oct 30, 2017 at 12:14:50PM -0500, Brett Neumeier wrote:
> > Hi all,
> >
> > I have a system working well with the combination of
> s6/s6-rc/s6-linux-init
> > -- all of which work for me exactly as documented. So I don't have any
> > problems, really!
> >
> > But I do have a question: as documented, I find that when stage1's child
> > process execs into stage2, there is a devtmpfs mounted at /dev. I don't
> > understand where this happens! I see where the stage 1 script mounts a
> > tmpfs at /run, but I don't see anything there, or in the initial s6
> > scandir, that mounts /dev. What am I missing?
> Assuming a distro, the initramfs handles that. It also handles mounting
> /sys and running an initial udev coldplug cycle.
> >
> > Cheers!
> >
> > Brett
> >
> > --
> > Brett Neumeier (bneume...@gmail.com)
>
> --
> Colin Booth
>


Re: Where does /dev get mounted?

2017-10-30 Thread Laurent Bercot
But I do have a question: as documented, I find that when stage1's 
child

process execs into stage2, there is a devtmpfs mounted at /dev. I don't
understand where this happens! I see where the stage 1 script mounts a
tmpfs at /run, but I don't see anything there, or in the initial s6
scandir, that mounts /dev. What am I missing?


 If you created your stage 1 script with s6-linux-init-maker, and you
see nothing in your stage 1 that mounts /dev, it means that you told
s6-linux-init-maker that your kernel automounts /dev at boot time.

 So, your /dev is already mounted when the kernel spawns init. The
kernel option triggering that behaviour is named CONFIG_DEVTMPFS_MOUNT.

--
 Laurent



Where does /dev get mounted?

2017-10-30 Thread Brett Neumeier
Hi all,

I have a system working well with the combination of s6/s6-rc/s6-linux-init
-- all of which work for me exactly as documented. So I don't have any
problems, really!

But I do have a question: as documented, I find that when stage1's child
process execs into stage2, there is a devtmpfs mounted at /dev. I don't
understand where this happens! I see where the stage 1 script mounts a
tmpfs at /run, but I don't see anything there, or in the initial s6
scandir, that mounts /dev. What am I missing?

Cheers!

Brett

-- 
Brett Neumeier (bneume...@gmail.com)