Subject: bug#41189: closed (Re: [bug#41189] [PATCH v2 0/4] Add Fakechroot engine for 'guix pack -RR')

From: [email-masked] (GNU bug Tracking System)
Date: Thu, 14 May 2020 15:25:02 +0000

Your bug report

#41189: [PATCH 0/3] Add Fakechroot engine for 'guix pack -RR'

which was filed against the guix-patches package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
41189: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=41189
GNU Bug Tracking System
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Subject: Re: [bug#41189] [PATCH v2 0/4] Add Fakechroot engine for 'guix pack -RR'
From: Ludovic Courtès <[email-masked]>
To: [email-masked]
Date: Thu, 14 May 2020 17:24:04 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

Ludovic Courtès <[email-masked]> skribis:

>   pack: Wrapper honors 'GUIX_EXECUTION_ENGINE' environment variable.
>   pack: Factorize store references in wrapper.
>   gnu: Add fakechroot.
>   pack: Add relocation via ld.so and fakechroot.

Pushed as 6456232164890dbf5aa20394ee24637feb4b7b9e!

Ludo’.

Subject: [PATCH 0/3] Add Fakechroot engine for 'guix pack -RR'
From: Ludovic Courtès <[email-masked]>
To: [email-masked]
Cc: Ludovic Courtès <[email-masked]>
Date: Mon, 11 May 2020 19:05:54 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

Hello Guix!

‘guix pack -RR’ is wonderful, as we know ;-), because it produces
binaries that work everywhere.

However, the overhead of PRoot is sometimes inappropriate, in
particular for those who want to run packed software on
high-performance computers, the very kind of machine that lacks
Guix and unprivileged user namespaces.

This patch series adds an optional “execution engine” to wrappers
that uses ld.so and fakechroot LD_PRELOAD trickery.  Since it’s
just LD_PRELOAD, there’s very little overhead, unlike PRoot.
On the flip side, it doesn’t work as well as PRoot, because it’s
“just” LD_PRELOAD.

For example, some of the ‘open’ calls made in libc are not
intercepted; on such call is in ‘__gconv_load_cache’, which makes
it fail, and in turn makes Guile fail to start in its first
‘scm_to_locale_string’ call.  Things that work well include Bash
and Python 3.  Let me know how well it works for your favorite
application!

The execution engine can now be chosen at run time by setting the
‘GUIX_EXECUTION_ENGINE’.

For the record, tools like udocker support a similar range of
execution engines: <https://github.com/indigo-dc/udocker/>.

Feedback welcome!

Thanks,
Ludo’.

Ludovic Courtès (3):
  pack: Wrapper honors 'GUIX_EXECUTION_ENGINE' environment variable.
  gnu: Add fakechroot.
  pack: Add relocation via ld.so and fakechroot.

 doc/guix.texi                             |  43 +++-
 gnu/packages/aux-files/run-in-namespace.c | 250 ++++++++++++++++++++--
 gnu/packages/linux.scm                    |  30 +++
 guix/scripts/pack.scm                     |  65 +++++-
 tests/guix-pack-relocatable.sh            |  23 ++
 5 files changed, 376 insertions(+), 35 deletions(-)

-- 
2.26.2