Re: [Qemu-devel] [PATCH v2 2/5] tests/docker: add podman support

[Debarshi Ray]

Hey,

Sorry for the late response. I was on vacation and away from my keyboard.

On Tue, Jul 9, 2019 at 9:44 PM Marc-André Lureau
<address@hidden> wrote:
> With current podman, we have to use a uidmap trick in order to be able
> to rw-share the ccache directory with the container user.
>
> With a user 1000, the default mapping is:
> 1000 (host) -> 0 (container).
>
> So write access to /var/tmp/ccache ends will end with permission
> denied error.
>
> With "--uidmap 1000:0:1 --uidmap 0:1:1000", the mapping is:
> 1000 (host) -> 0 (container, 1st namespace) -> 1000 (container, 2nd 
> namespace).
>
> (the rest is mumbo jumbo to avoid holes in the range of UIDs)
>
> A future podman version may have an option such as --userns-keep-uid.

The future is here! :)

Since Podman 1.4.0, released on 7th June 2019, you can use
--userns=keep-id instead of typing out the entire UID mapping. The
relevant Podman pull request is:
https://github.com/containers/libpod/pull/3196

Cheers,
Rishi