Re: [Qemu-devel] [PATCH 0/4] add "make check"

From: Gerd Hoffmann <kraxel@redhat.com>
To: Kevin Wolf <kwolf@redhat.com>, Avi Kivity <avi@redhat.com>,
	Markus Armbruster <armbru@redhat.com>,
	qemu-devel@nongnu.org, Lucas Meneghel Rodrigues <lmr@redhat.com>,
	Cleber Rosa <crosa@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 0/4] add "make check"
Date: Tue, 25 Oct 2011 17:54:32 +0200	[thread overview]
Message-ID: <4EA6DBB8.4050608@redhat.com> (raw)
In-Reply-To: <20111025150302.GC29718@otherpad.lan.raisama.net>

  Hi,

> Just trying to enumerate the kind of tests somebody may need:
> 
> A) Simple unit tests for internal qemu C functions
>    - 'make check' can run them, using either libcheck or gtest.

Yes, those tests should work and succeed anywhere where qemu compiles.

> B) Functional tests that tests actual virtualization/emulation, but only
>    of some specific subsystems, not using a fully-featured qemu process.
>    - We don't have anything like that, today, right? I am not sure we
>      need it.

qemu-kvm used to have such tests.  There is no point in not using qemu
here though, thats why they where transformed into (C).

> C) Functional tests that just need to run a small binary with no OS
>    installed in the guest, but running a fully-feature qemu process.
>    - The tests in the 'tests' directory do this, right? kvm-unittests
>      does this, right?

kvm-unittests yes.

tests/ seems to be a somewhat bitrotted random collection of tests.

> D) Functional tests that need a minimal OS installed, with, e.g., at
>    least a Linux kernel and a shell.
>    - This is what Gerd's patch below does, right? Also, KVM-Autotest can
>      be used for this.

What the patch tries is to use the bits which are on the host anyway to
run guest tests (obviously linux-on-linux only), so we can do parts of
(E) with less configuration, less internet bandwith (no iso downloads),
less disk space requirements (no iso + disk storage) and faster (no
guest installs needed).  Didn't try yet to mount the host filesystem
using 9p yet, with that we could possibly take the approach quite far as
we suddenly don't have just a "minimal os" any more but alot more.

Using the host bits is at the same time a possible trouble spot.  There
are lots of different distros with more or less subtile differences out
there.  Each machine has a different set of packages installed.  So
having this "just work" everythere probably isn't that easy ...

> E) Functional tests that need a full OS installed and configured.
>    - Today we use KVM-Autotest for this.

cheers,
  Gerd