doc: Clarify /dev/kvm setup.

Reported by myglc2 <myglc2@gmail.com>.

* doc/guix.texi (Build Environment Setup): Mention the "kvm" group.
(Invoking guix system): Use "@quotation Note" for the note about KVM;
make it clear that KVM is optional.
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Ludovic Courtès 2016-06-26 12:16:07 +02:00
parent 4b67053962
commit eca69fc0d6
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@ -708,8 +708,13 @@ Bash syntax and the @code{shadow} commands):
@noindent
The number of build users determines how many build jobs may run in
parallel, as specified by the @option{--max-jobs} option
(@pxref{Invoking guix-daemon, @option{--max-jobs}}). The
@code{guix-daemon} program may then be run as @code{root} with the
(@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
@command{guix system vm} and related commands, you may need to add the
build users to the @code{kvm} group so they can access @file{/dev/kvm},
using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
(@pxref{Invoking guix system}).
The @code{guix-daemon} program may then be run as @code{root} with the
following command@footnote{If your machine uses the systemd init system,
dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
file in @file{/etc/systemd/system} will ensure that
@ -10224,12 +10229,14 @@ a list of available debugging commands.
@end table
@end table
Note that all the actions above, except @code{build} and @code{init},
rely on KVM support in the Linux-Libre kernel. Specifically, the
machine should have hardware virtualization support, the corresponding
@quotation Note
All the actions above, except @code{build} and @code{init},
can use KVM support in the Linux-libre kernel. Specifically, if the
machine has hardware virtualization support, the corresponding
KVM kernel module should be loaded, and the @file{/dev/kvm} device node
must exist and be readable and writable by the user and by the
build users of the daemon.
build users of the daemon (@pxref{Build Environment Setup}).
@end quotation
Once you have built, configured, re-configured, and re-re-configured
your GuixSD installation, you may find it useful to list the operating