From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ludovic =?UTF-8?Q?Court=C3=A8s?= <ludo@gnu.org>
Subject: bug#36335: Is /dev/kvm missing ACLs?
Date: Thu, 27 Jun 2019 15:45:33 +0200
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To: Chris Marusich <cmmarusich@gmail.com>
Cc: 36335@debbugs.gnu.org

Hi Chris,

Chris Marusich <cmmarusich@gmail.com> skribis:

> Ludovic Court=C3=A8s <ludo@gnu.org> writes:
>
>> Guix System doesn=E2=80=99t use ACLs at all.
>>
>> However, the udev rule for kvm sets it up like this:
>>
>>   crw-rw---- 1 root kvm 10, 232 Jun 24 08:38 /dev/kvm
>>
>> and the build users are part of the =E2=80=98kvm=E2=80=99 group.  I pers=
onally arrange
>> to have my user account in that group too.
>
> It's good to know that the "kvm" group is the right way to grant
> permissions.  However, if Guix System doesn't use ACLs, then why do some
> of my device files have ACLs on them, such as the video device file?
>
> $ getfacl /dev/video0=20
> getfacl: Removing leading '/' from absolute path names
> # file: dev/video0
> # owner: root
> # group: video
> user::rw-
> user:marusich:rw-
> group::rw-
> mask::rw-
> other::---

Good question, I see the same thing here.

I suspected a udev rule but =E2=80=98grep=E2=80=99 didn=E2=80=99t find any =
that explicitly does
that, and there=E2=80=99s no code in eudev that fiddles with ACLs either, a=
nd
nothing obvious in devtmpfs.c in Linux.  So=E2=80=A6 it=E2=80=99s a mystery.

Ludo=E2=80=99.