Re: device namespaces

From: Hannes Reinecke
Date: Wed Jun 09 2021 - 03:02:57 EST


On 6/9/21 8:38 AM, Christian Brauner wrote:
On Tue, Jun 08, 2021 at 12:16:43PM -0500, Eric W. Biederman wrote:
Hannes Reinecke <hare@xxxxxxx> writes:

On 6/8/21 4:29 PM, Christian Brauner wrote:
On Tue, Jun 08, 2021 at 04:10:08PM +0200, Hannes Reinecke wrote:
[ .. ]
Granted, modifying sysfs layout is not something for the faint-hearted,
and one really has to look closely to ensure you end up with a
consistent layout afterwards.

But let's see how things go; might well be that it turns out to be too
complex to consider. Can't tell yet.

I would suggest aiming for something like devptsfs without the
complication of /dev/ptmx.

That is a pseudo filesystem that has a control node and virtual block
devices that were created using that control node.

Also see android/binder/binderfs.c

Ah. Will have a look.


That is the cleanest solution I know and is not strictly limited to use
with containers so it can also gain greater traction. The interaction
with devtmpfs should be simply having devtmpfs create a mount point for
that filesystem.

This could be a new cleaner api for things like loopback devices.

I sent a patchset that implemented this last year.

Do you have a pointer/commit hash for this?

Cheers,

Hannes
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Dr. Hannes Reinecke Kernel Storage Architect
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