Test Suite - KVM: Difference between revisions

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== KVM Test framework ==


Libreswan comes with an extensive test suite, written mostly in python, that uses KVM virtual machines and virtual networks. It has replaced the old UML test suite.
Libreswan's test framework can be run using KVM guests, and the kvm scripts. It is strongly recommended to run the test suite on a host machine that has a CPU wth virtualisation instructions.
Apart from KVM, the test suite uses libvirtd and qemu. It is strongly recommended to run the test suite natively on the OS (not in a VM itself) on a machine that has a CPU wth virtualization instructions.
The PLAN9 filesystem (9p) is used to mount host directories in the guests - NFS is avoided to prevent network lockups when an IPsec test case would cripple the guest's networking.  


{{ ambox | nocat=true | type=important | text = libvirt 0.9.11 and qemu 1.0 or better are required. RHEL does not support a writable 9p filesystem, so the recommended host/guest OS is Fedora 22 }}
To access files on the host file system:


[[File:testnet.png]]
* Linux guests (Fedora) use the PLAN9 filesystem (9p)
* BSD guests (FreeBSD, NetBSD, OpenBSD) use NFS via the NAT interface


== Test Frameworks ==
For an overview of the tests see [[Test_Suite]]


This page describes the make kvm framework.
== Preparing the host machine ==


Instead of using virtual machines, it is possible to use Docker instances.
=== Check Virtualization is enabled in the BIOS ===


More information is found in [[Test Suite - Docker]] in this Wiki
Virtualization needs to be enabled by the BIOS during boot.


== Preparing the host machine ==
  grep -e vmx -e svm /proc/cpuinfo


In the following it is assumed that your account is called "build".
=== Add yourself to <tt>sudo</tt> ===
 
=== Add Yourself to sudo ===


Some of the test scrips need to be run as root.  The test environment assumes this can be done using <tt>sudo</tt> without a password vis:
Some of the test scrips need to be run as root.  The test environment assumes this can be done using <tt>sudo</tt> without a password vis:


<pre>
sudo pwd
sudo pwd
</pre>


XXX: Surely qemu can be driven without root?
''XXX: Surely qemu can be driven without root?''


This is done by creating a no-pasword rule to /etc/sudoers.d/.
This is setup by adding an entry under /etc/sudoers.d/ specifying that your account does not need a password to become root:


To set this up, add your account to the wheel group and permit wheel to have no-password access. Issue the following commands as root:
echo "$(id -u -n) ALL=(ALL) NOPASSWD: ALL" | sudo dd of=/etc/sudoers.d/$(id -u -n)
 
<pre>
echo '%wheel ALL=(ALL) NOPASSWD: ALL' > /etc/sudoers.d/swantest
chmod 0440 /etc/sudoers.d/swantest
chown root.root /etc/sudoers.d/swantest
usermod -a -G wheel build
</pre>


=== Fight SELinux ===
=== Fight SELinux ===
Line 47: Line 36:
* set SELinux to permissive (recommended)
* set SELinux to permissive (recommended)


<pre>
sudo sed --in-place=.ORIG -e 's/^SELINUX=.*/SELINUX=permissive/' /etc/selinux/config
sudo sed --in-place=.ORIG -e 's/^SELINUX=.*/SELINUX=permissive/' /etc/selinux/config
sudo setenforce Permissive
sudo setenforce Permissive
</pre>


* disable SELinux
* disable SELinux


<pre>
sudo sed --in-place=.ORIG -e 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config
sudo sed --in-place=.ORIG -e 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config
sudo reboot
sudo reboot
</pre>


* (experimental) label source tree for SELinux
* (experimental) label source tree for SELinux
Line 63: Line 48:
The source tree on the host is shared with the virtual machines.  SELinux considers this a bug unless the tree is labelled with type svirt_image_t.
The source tree on the host is shared with the virtual machines.  SELinux considers this a bug unless the tree is labelled with type svirt_image_t.


<pre>
sudo dnf install policycoreutils-python-utils
sudo dnf install policycoreutils-python-utils
sudo semanage fcontext -a -t svirt_image_t "$(pwd)"'(/.*)?'
sudo semanage fcontext -a -t svirt_image_t "$(pwd)"'(/.*)?'
sudo restorecon -vR /home/build/libreswan
sudo restorecon -vR /home/build/libreswan
</pre>


There may be other things that SELinux objects to.
There may be other things that SELinux objects to.


=== Install Required Dependencies ===
=== Check that the host has enough entropy ===


Now we are ready to install the various components of libvirtd, qemu and kvm and then start the libvirtd service.
As a rough guide run:


Even virt-manager isn't strictly required.
while true ; do cat /proc/sys/kernel/random/entropy_avail ; sleep 3 ; done


On Fedora 28:
it should have values in the hundrets if not thousands.  If it is in the units or tens then see [[Entropy matters]]


<pre>
=== Install Dependencies ===
# is virt-manager really needed
sudo dnf install -y qemu virt-manager virt-install libvirt-daemon-kvm libvirt-daemon-qemu
sudo dnf install -y python3-pexpect
sudo dnf install -y make
</pre>


Once all is installed start libvirtd:
{| class="wikitable"
|-
! Why || Fedora !! Mint (debian)
|-
| Basics
|| sudo dnf install -y make git gitk patch
|| sudo apt-get install -y make make-doc git gitk
|-
| Python
|| sudo dnf install -y python3-pexpect
|| sudo apt-get install python3-pexpect
|-
| Virtulization
|| sudo dnf install -y qemu virt-install libvirt-daemon-kvm libvirt-daemon-qemu
|| sudo apt install -y qemu virtinst libvirt-clients libvirt-daemon libvirt-daemon-system libvirt-daemon-driver-qemu libosinfo-query qemu-system-x86?
|-
| Boot CDs
|| sudo dnf install -y dvd+rw-tools
|| sudo apt-get install -y dvd+rw-tools
|-
| Web Pages
|| sudo dnf install -y jq nodejs-typescript
|| sudo apt-get install -y jq node-typescript
|-
| Web Server (optional)
|| sudo dnf install -y httpd
|| sudo apt-get install -y ????
|-
| NFS
|| sudo dnf install -y nfs-utils # ???
|| sudo apt-get install -y nfs-kernel-server rpcbind
|-
| Broken makefiles
|| sudo dnf install -y nss-devel # make file invokes pkg-config nss
||
|}


<pre>
=== Enable libvirt ===
sudo systemctl enable libvirtd
sudo systemctl start libvirtd
</pre>


On Debian?
''If you're switching from the old libvirtd see https://libvirt.org/daemons.html#switching-to-modular-daemons for how to shut down the old daemons.''


=== Install Utilities (Optional) ===
Start the "collection of modular daemons that replace functionality previously provided by the monolithic libvirtd daemon":


Various tools are used or convenient to have when running tests:
for drv in qemu network nodedev nwfilter secret storage interface
do
    sudo systemctl unmask virt${drv}d.service
    sudo systemctl unmask virt${drv}d{,-ro,-admin}.socket
    sudo systemctl enable virt${drv}d.service
    sudo systemctl enable virt${drv}d{,-ro,-admin}.socket
done
for drv in qemu network nodedev nwfilter secret storage
do
    sudo systemctl start virt${drv}d{,-ro,-admin}.socket
done


Optional packages to install on Fedora
There should be no errors and warnings.


<pre>
=== Stop libvirt daemons shutting down ===
sudo dnf -y install git patch tcpdump expect python-setproctitle python-ujson pyOpenSSL python3-pyOpenSSL
sudo dnf install -y python2-pexpect python3-setproctitle diffstat
</pre>


Optional packages to install on Ubuntu
By default the libvirt daemons timeout and shutdown after 120 seconds (surely systemd will restart them!).  It turns out this hasn't worked so well:


<pre>
* [https://bugzilla.redhat.com/show_bug.cgi?id=2213660 | libvirt clients hang because virtnetworkd.service misses when virtnetworkd is dead]
apt-get install python-pexpect git tcpdump  expect python-setproctitle python-ujson \
: systemd doesn't restart the daemon
        python3-pexpect python3-setproctitle
* [https://bugzilla.redhat.com/show_bug.cgi?id=2075736| error: Disconnected from qemu:///system due to keepalive timeout]
</pre>
: the restart is painfully slow with lots of networks which causes the timeout
* [https://bugzilla.redhat.com/show_bug.cgi?id=2111582 | libvirtd deadlocks] (fixed)
* [https://bugzilla.redhat.com/show_bug.cgi?id=2123828 | virtqemud gets slower and slower]


{{ ambox | nocat=true | type=important | text = do not install strongswan-libipsec because you won't be able to run non-NAT strongswan tests! }}
Disabling the timeout and just leaving the daemons running seems to help.  Add the following:


=== Setting Users and Groups ===
  echo VIRTNETWORKD_ARGS= > /etc/sysconfig/virtnetworkd
  echo VIRTQEMUD_ARGS= > /etc/sysconfig/virtqemud
  echo VIRTSTORAGED_ARGS= > /etc/sysconfig/virtstoraged


You need to add yourself to the qemu group.  For instance:
the standard libvirt systemd config files read these settings using EnvironmentFile=


<pre>
=== Add yourself to the KVM/QEMU group ===
sudo usermod -a -G qemu $(id -u -n)
</pre>


You will need to re-login for this to take effect.
You need to add yourself to the group that QEMU/KVM uses when writing to /var/lib/libvirt/qemu.  On Fedora it is 'qemu', and on Debian it is 'kvm'. Something like:


The path to your build needs to be accessible (executable) by root:
sudo usermod -a -G $(stat --format %G /var/lib/libvirt/qemu) $(id -u -n)


<pre>
After this you will will need to re-login (or run <tt>sudo su - $(id -u -n)</tt>
chmod a+x ~
 
</pre>
=== Make certain that <tt>root</tt> can access the build ===
 
The path to your build needs to be accessible (executable) by root, assuming things are under home:
 
chmod a+x $HOME


=== Fix /var/lib/libvirt/qemu ===
=== Fix /var/lib/libvirt/qemu ===
Line 135: Line 158:
{{ ambox | nocat=true | type=important | text = Because our VMs don't run as qemu, /var/lib/libvirt/qemu needs to be changed using chmod g+w to make it writable for the qemu group. This needs to be repeated if the libvirtd package is updated on the system }}
{{ ambox | nocat=true | type=important | text = Because our VMs don't run as qemu, /var/lib/libvirt/qemu needs to be changed using chmod g+w to make it writable for the qemu group. This needs to be repeated if the libvirtd package is updated on the system }}


<pre>
sudo chmod g+w /var/lib/libvirt/qemu
sudo chmod g+w /var/lib/libvirt/qemu
 
</pre>
Arguably we should run libvirt as a normal user instead.


=== Create /etc/modules-load.d/virtio.conf ===
=== Create /etc/modules-load.d/virtio.conf (obsolete since 2022 at least) ===


Several virtio modules need to be loaded into the host's kernel.  This could be done by modprobe ahead of running any virtual machines but it is easier to install them whenever the host boots.  This is arranged by listing the modules in a file within /etc/modules-load.d.  The host must be rebooted for this to take effect.
Several virtio modules need to be loaded into the host's kernel.  This could be done by modprobe ahead of running any virtual machines but it is easier to install them whenever the host boots.  This is arranged by listing the modules in a file within /etc/modules-load.d.  The host must be rebooted for this to take effect.


<pre>
sudo dd <<EOF of=/etc/modules-load.d/virtio.conf
sudo dd <<EOF of=/etc/modules-load.d/virtio.conf
virtio_blk
virtio_blk
virtio-rng
virtio-rng
virtio_console
virtio_console
virtio_net
virtio_net
virtio_scsi
virtio_scsi
virtio
virtio
virtio_balloon
virtio_balloon
virtio_input
virtio_input
virtio_pci
virtio_pci
virtio_ring
virtio_ring
9pnet_virtio
9pnet_virtio
EOF
EOF
 
</pre>
As of Fedora 28, several of these modules are built into the kernel and will not show up in /proc/modules (virtio, virtio_rng, virtio_pci, virtio_ring).
 
=== Set up a Web Server (optional) ===


As of Fedora 28, several of these modules are now built into the kernel and will not show up in /proc/modules (virtio, virtio_rng, virtio_pci, virtio_ring).
If the machine is to run nightly test runs then it can be set up as a web server.
See the [http://testing.libreswan.org nightly test results] for an example.


=== Ensure that the host has enough entropy ===
See above for dependencies.  See below for how to configure libreswan.


[[Entropy matters]]
To set up the server:


With KVM, a guest systems uses entropy from the host through the kernel module "virtio_rng" in the guest's kernel (set above).  This has advantages:
sudo mkdir /var/www/html/results/
sudo chown $(id -un) /var/www/html/results/
sudo chmod 755 /var/www/html/results/
sudo sh -c 'echo "AddType text/plain .diff" >/etc/httpd/conf.d/diff.conf'


* entropy only needs to be gathered on one machine (the host) rather than all machines (the host and the guests)
to run the web server until the next reboot:
* the host is in the Real World and thus has more sources of real entropy
* any hacking to make entropy available need only be done on one machine


To ensure the host has enough randomness, run either jitterentropy-rngd or havegd.
sudo firewall-cmd --add-service=http
  sudo systemctl start httpd
to make the web server permanent:


Fedora commands for using jitterentropy-rngd (broken on F26, service file specifies /usr/local for path):
sudo systemctl enable httpd
<pre>
sudo firewall-cmd --add-service=http --permanent
sudo dnf install jitterentropy-rngd
sudo systemctl enable jitterentropy-rngd
sudo systemctl start jitterentropy-rngd
</pre>


Fedora commands for using havegd:
If you want it to be the main page of the website, you can create the file /var/www/html/index.html containing:


<pre>
cat <<EOF
sudo dnf install haveged
<pre>
sudo systemctl enable haveged
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
sudo systemctl start haveged
<html>
</pre>
  <head>
    <meta http-equiv="REFRESH" content="0;url=/results/">
  </head>
  <BODY>
  </BODY>
</HTML>
</pre>
EOF
 
=== Debian ===
 
On Debian slack based systems (i.e., Linux Mint 20.3), the default python is too old.  Fortunately python 3.9 is also available vis:
 
sudo apt-get install python3.9
 
in addition, the make variable KVM_PYTHON will need to be added to Makefile.inc.local, see below.
 
=== BSD ===
 
Anyone?


== Download and configure libreswan ==
== Download and configure libreswan ==
Line 194: Line 239:
The libreswan source tree includes all the components that are used on the host and inside the test VMs. To get the latest source code using git:
The libreswan source tree includes all the components that are used on the host and inside the test VMs. To get the latest source code using git:


<pre>
git clone https://github.com/libreswan/libreswan
git clone https://github.com/libreswan/libreswan
cd libreswan
cd libreswan
 
</pre>
Developers can use Makefile.inc.local to override default build setttings.  Create the file:
 
touch Makefile.inc.local
 
(packaging systems should not use this, and instead explicitly pass the make variables to the make command)
 
=== (optional) Override python ===
 
See above.  If pthon isn't new enough (for instance on Debian) set KVM_PYTHON in Makefile.inc.local vis:
 
echo KVM_PYTHON=python3.9 >> Makefile.inc.local
 
=== Create the Pool directory for storing VM disk images - $(KVM_POOLDIR) ===
 
The pool directory is used used to store:
 
* VM disk images
* install CD/DVD images
* downloaded packages installed into the VMs
* other files
 
and can get quite large.  It can and should be shared between build trees (this reflects libvirt which has a single name space for domains).  KVM_PREFIXES (see further down) addresses the lack of name spaces.
 
By default $(top_srcdir)/../pool (../pool) is used (that is, adjacent to your source tree).  It will need to be created.


=== Create the Pool directory - KVM_POOLDIR ===
Alternatively the shared pool directory can be specified explicitly by setting the make variable KVM_POOLDIR in Makefile.inc.local vis:


The pool directory is used used to store KVM disk images and other configuration files. By default $(top_srcdir)/../pool is used (that is, adjacent to your source tree).
mkdir KVM_POOLDIR=/home/libreswan/pool
  echo KVM_POOLDIR=/home/libreswan/pool >> Makefile.inc.local


To change the location of the pool directory, set the KVM_POOLDIR make variable in Makefile.inc.local.  For instance:
=== (optional) Use /tmp/pool (tmpfs) to store test VM disk images - $(KVM_LOCALDIR) ===


<pre>
By default, all disk mages are stored in $(KVM_POOLDIR) (see above). Since the test VM disk images do not need long-term storage (i.e., survive a reboot), $(KVM_LOCALDIR) can be used to specify that test VM disk images are stored in /tmp vis:
$ grep KVM_POOLDIR Makefile.inc.local
KVM_POOLDIR=/home/libreswan/pool
</pre>


=== Make tests run in parallel - KVM_PREFIXES ===
echo KVM_LOCALDIR=/tmp/pool >> Makefile.inc.local
This has the advantage of eliminating physical disk I/O as a bottle neck when accessing VM disk images; but the disadvantage of needing to re-build the test disk images after a reboot.


By default only one test is run at a time.  This can be changed using KVM_PREFIXES make variable which specifies the prefix to prepend to test domains.  The default value is:
=== (optional) Define test groups and run tests in parallel - $(KVM_PREFIXES) ===


<pre>
By default there is only one set of build and test domains.  This means that a host can only support one build tree, and that tests are run sequentially.
KVM_PREFIXES=''
</pre>


which creates the domains ''east, ''west, et.al. (i.e., after expansion east, west, et.al.).
This can be changed by setting the KVM_PREFIXES make variable in Makefile.inc.local. This specifies a list of prefixes to be pretended to build and test domains creating multiple test groups.


Multiple tests can be run in parallel by specifying more prefixes - a rule of thumb is one prefix per two CPU cores.  For instance, on a 4-core machine, two prefixes can be specified using:
The default value is:


<pre>
KVM_PREFIXES=''
KVM_PREFIXES='' 1.
</pre>


which creates, after expansion, the domains east, west, et.al. and 1.east, 1.west, et.al.
which creates the build domains ''fedora-base, ''fedora-upgrade, ''fedora, et.al., and the test domains ''east, ''west, et.al. (i.e., after expansion fedora-base, fedora-upgrade, fedora, east, west, et.al.).


=== Serve test results as HTML pages on the test server (optional) ===
To run tests in parallel and assign unique domains to the build directory, specify multiple prefixes.  For instance a build tree can be given unique domains and run two tests in parallel by specifying:


If you want to be able to see the results of testruns in HTML, you can enable a webserver:
KVM_PREFIXES=t1 t2


<pre>
This will create the build domains t1fedora-base, t1fedora-upgrade, t1fedora, et.al., and the test domains t1east, t2east, et.al.
dnf install httpd
systemctl enable httpd
systemctl start httpd
mkdir /var/www/html/results/
chown build /var/www/html/results/
chmod 755 /var/www/html/results/
cd ~
ln -s /var/www/html/results
</pre>


If you want it to be the main page of the website, you can create the file /var/www/html/index.html containing:
Due to limitations in the network stack (networks with prefix t. and t2. are also created) the prefix needs to be short.
 
{{ ambox | nocat=true | type=important | text = TODO: generate $(KVM_PREFIXES) from $(KVM_PREFIX) and $(KVM_WORKERS) so that the build domains are prefixed by $(KVM_PREFIX) and the test domains are prefixed by $(KVM_PREFIX), $(KVM_PREFIX)2, ..., $(KVM_PREFIX)$(KVM_WORKERS); only create the first test domains and then create the rest as runtime snapshots. }}
 
=== (optional) Parallel builds - $(KVM_WORKERS) ===
 
By default, build domains only have on virtual CPU.  Since building is very CPU intensive, this can be increased using $(KVM_WORKERS).
 
KVM_WORKERS=2


<pre>
{{ ambox | nocat=true | type=important | text = In the past, because many tests were racy (results were sensitive to CPU load) KVM_WORKERS was used throttle the number of domains been booted in parallel (it is very CPU intensive).  That is no longer true.  See notes under KVM_PREFIXES above. }}
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<meta http-equiv="REFRESH" content="0;url=/results/"></HEAD>
<BODY>
</BODY>
</HTML>
</pre>


and then add:
=== (optional) Generate a web page of the test results ===


<pre>
See the [http://testing.libreswan.org nightly test results] for an example and how to set up a web server so results can be viewed remotely.
WEB_SUMMARYDIR=/var/www/html/results
</pre>


To Makefile.inc.local
To initially create the web directory <tt>RESULTS/</tt> and populate it with the current test results use:


== Set up KVM and run the Testsuite (for the impatient) ==
make web


If you're impatient, and want to just run the testsuite using kvm then:
Further test runs will update the <tt>RESULTS/</tt> directory.  The files can the be viewed using http://file.


* install (or update) libreswan (if needed this will create the test domains):
To disable web page generation, delete the directory <tt>RESULTS/</tt>.
: <tt>make kvm-install</tt>
* run the testsuite:
: <tt>make kvm-test</tt>
* list the kvm make targets:
: <tt>make kvm-help</tt>


After that, the following make targets are useful:
To instead publish the results on the web, point <tt>$(WEB_SUMMARYDIR)</tt> at the web directory:


* clean the kvm build tree
$ WEB_SUMMARYDIR=/var/www/html/results >> Makefile.inc.local
: <tt>make kvm-clean</tt>
* clean the kvm build tree and all kvm domains
: <tt>make kvm-purge</tt>


== Running the testsuite ==
== Running the testsuite ==


=== Generating Certificates ===
In the past, the testsuite was driven using <tt>make kvm-...</tt> commands.  That's largely been replaced by the top-level wrapper script <tt>./kvm</tt> which has several advantages over make:
 
* it is file (file) completion friendly
* it is shell script friendly
 
=== For the impatient: <tt>./kvm install check</tt>  ===


The full testsuite requires a number of certificates.  The virtual domains are configured for this purpose.  Just use:
To build the VMs, and build and install (or update) libreswan, and then run the tests, use:


<pre>
./kvm install check
make kvm-keys
</pre>


( ''Before pyOpenSSL version 0.15 you couldn't run dist_certs.py without a patch to support creating SHA1 CRLs.
=== Setting up <tt>./kvm</tt> (tab completion) ===
A patch for this can be found at'' https://github.com/pyca/pyopenssl/pull/161 )


=== Run the testsuite ===
If this:


To run all test cases (which include compiling and installing it on all vms, and non-VM based test cases), run:
complete -o filenames -C './kvm' ./kvm


<pre>
is added to  <tt>.bashrc</tt> then tab completion with <tt>./kvm</tt> will include both commands and directories.
make kvm-install kvm-test
</pre>


=== Stopping pluto tests (gracefully) ===
=== Running the testsuite ===


If you used "make kvm-test", type control-C; possibly repeatedly.
; ./kvm install
: update the KVMs ready for a new test run
 
; ./kvm check
: run the testsuite, previous results are saved in <tt>BACKUP/-date-</tt>
 
; ./kvm recheck
: run the testsuite, but skip tests that already passed
 
; ./kvm results
: list the results from the test run
 
; ./kvm diffs
: display differences between the test results and the expected results, exit non-zero if there are any
 
the operations can be combined on a single line:
 
./kvm install check recheck diff
 
and individual tests can be selected (see Running a Single Test, below):
 
./kvm install check diff testing/pluto/*ikev2*
 
To stop <tt>./kvm</tt> use control-c.
 
=== Updating Certificates ===
 
The full testsuite requires a number of certificates.  If not present, then <tt>./kvm check</tt> will automatically generate them using the domain <tt>build</tt>.  Just note that the certificates have a limited lifetime.  Should the test system detects out-of-date certificates then <tt>./kvm check</tt> will barf.
 
To rebuild the certificates:
 
; ./kvm keys
 
can be used to force the generation of new certificates.
 
=== Cleaning up (and general maintenance) ===
 
; ./kvm check-clean
: delete the test results
 
; ./kvm uninstall
; delete the KVM build and test domains (but don't touch the build tree or test results)
 
; ./kvm clean
: delete the test results, the KVM build and test domains, the build tree, and the certificates
 
; ./kvm purge
: also delete the test networks (is purge still useful?)
 
; ./kvm demolish
: also delete the KVM base domain that was used to create the other domains
 
; ./kvm upgrade
: delete all KVM build and test domains, and then upgrade and transmogrify the base domain ready for a fresh install
 
; ./kvm transmogrify
: run a fresh transmogrify on the base domain (the base domain is reverted to before the last transmogrify)
 
; ./kvm downgrade
: revert the base domain back to before it was upgraded (useful when debugging upgrade and transmogrify)


== Shell and Console Access (Logging In) ==
== Shell and Console Access (Logging In) ==
Line 315: Line 419:
* while SSH takes more to set up, it supports things like proper terminal configuration and file copy
* while SSH takes more to set up, it supports things like proper terminal configuration and file copy


=== Serial Console access using "make kvmsh-HOST" (kvmsh.py) ===
=== Serial Console access using <tt>./kvm sh HOST</tt> (kvmsh.py) ===


"kvmsh", is a wrapper around "virsh".  It automatically handles things like booting the machine, logging in, and correctly configuring the terminal:
<tt>./kvm sh HOST</tt> is a wrapper around "virsh" that automatically handles things like booting the machine, logging in, and correctly configuring the terminal.  It's big advantage is that it always works.  For instance:


<pre>
$ ./testing/utils/kvmsh.py east
$ ./testing/utils/kvmsh.py east
[...]
[...]
Escape character is ^]
Escape character is ^]
[root@east ~]# printenv TERM
[root@east ~]# printenv TERM
xterm
xterm
[root@east ~]# stty -a
[root@east ~]# stty -a
...; rows 52; columns 185; ...  
...; rows 52; columns 185; ...  
[root@east ~]#
[root@east ~]#
</pre>


"kvmsh.py" can also be used to script remote commands (for instance, it is used to run "make" on the build domain):
The script "kvmsh.py" can also be used directly to invoke commands on a guest (this is how <tt>./kvm install</tt> works):


<pre>
$ ./testing/utils/kvmsh.py east ls
$ ./testing/utils/kvmsh.py east ls
[root@east ~]# ls
[root@east ~]# ls
anaconda-ks.cfg
anaconda-ks.cfg
</pre>


Finally, "make kvmsh-HOST" provides a short cut for the above; and if your using multiple build trees (see further down), it will connect to the DOMAIN that corresponds to HOST.  For instance, notice how the domain "a.east" is passed to kvmsh.py in the below:
When $(KVM_PREFIXES) contains multiple prefixes, <tt>./kvm sh east</tt> always logs into the first prefixe's domain.
 
<pre>
$ make kvmsh-east
/home/libreswan/pools/testing/utils/kvmsh.py --output ++compile-log.txt --chdir . a.east
Escape character is ^]
[root@east source]#
</pre>


Limitations:
Limitations:


* no file transfer but files can be accessed via /testing
* no file transfer but files can be accessed via <tt>/pool</tt> and </tt>/testing</tt>


=== Graphical Console access using virt-manager ===
=== Graphical Console access using virt-manager ===
Line 357: Line 449:


While easy to use, it doesn't support cut/paste or mechanisms for copying files.
While easy to use, it doesn't support cut/paste or mechanisms for copying files.


=== Shell access using SSH ===
=== Shell access using SSH ===


While requiring slightly more effort to set up, it provides full shell access to the domains.
While requiring more effort to set up, it provides full shell access to the domains.


Since you will be using ssh a lot to login to these machines, it is recommended to either put their names in /etc/hosts:
Since you will be using ssh a lot to login to these machines, it is recommended to either put their names in /etc/hosts:


<pre>
# /etc/hosts entries for libreswan test suite
# /etc/hosts entries for libreswan test suite
192.1.2.45 west
192.1.2.45 west
192.1.2.23 east
192.1.2.23 east
192.0.3.254 north
192.0.3.254 north
192.1.3.209 road
192.1.3.209 road
192.1.2.254 nic
192.1.2.254 nic
</pre>


or add entries to .ssh/config such as:
or add entries to .ssh/config such as:


<pre>
Host west
Host west
         Hostname 192.1.2.45
         Hostname 192.1.2.45
</pre>


If you wish to be able to ssh into all the VMs created without using a password, add your ssh public key to '''testing/baseconfigs/all/etc/ssh/authorized_keys'''. This file is installed as /root/.ssh/authorized_keys on all VMs
If you wish to be able to ssh into all the VMs created without using a password, add your ssh public key to '''testing/baseconfigs/all/etc/ssh/authorized_keys'''. This file is installed as /root/.ssh/authorized_keys on all VMs


Using ssh becomes easier if you are running ssh-agent (you probably are) and your public key is known to the virtual machine.  This command, run on the host, installs your public key on the root account of the guest machines west.  This assumes that west is up (it might not be, but you can put this off until you actually need ssh, at which time the machine would need to be up anyway).  Remember that the root password on each guest machine is "swan".
Using ssh becomes easier if you are running ssh-agent (you probably are) and your public key is known to the virtual machine.  This command, run on the host, installs your public key on the root account of the guest machines west.  This assumes that west is up (it might not be, but you can put this off until you actually need ssh, at which time the machine would need to be up anyway).  Remember that the root password on each guest machine is "swan".
<pre>
 
ssh-copy-id root@west
ssh-copy-id root@west
</pre>
 
You can use ssh-copy for any VM.  Unfortunately, the key is forgotten when the VM is restarted.
You can use ssh-copy for any VM.  Unfortunately, the key is forgotten when the VM is restarted.


== Run an individual test (or tests) ==
Limitations:
 
* this only works with the default east, et.al. (it does not work with KVM_PREFIXES and/or multiple test directories)
 
== kvm workflows ==
 
(seeing as everyone has a "flow", why not kvm) here are some common workflows, the following commands are used:
 
; ./kvm modified
: list the test directories that have been modified
; ./kvm baseline
: compare test results against a baseline
; ./kvm patch
: update the expected test results
; ./kvm add
: <tt>git add</tt> the modified test results
; ./kvm status
: show the status of the currently running testsuite
; ./kvm kill
: kill the currently running testsuite
 
=== Running a single test ===
 
There are two ways to run an individual test:


All the test cases involving VMs are located in the libreswan directory under testing/pluto/ . The most basic test case is called basic-pluto-01. Each test case consists of a few files:
# the test to run can be specified on the command line:
#: kvm check testing/pluto/basic-pluto-01
# the test is implied when running <tt>kvm</tt> from a test directory:
#: cd testing/pluto/basic-pluto-01
#: ../../../kvm
#: ../../../kvm diff


* description.txt to explain what this test case actually tests
But there's a catch:
* ipsec.conf files - for host west is called west.conf. This can also include configuration files for strongswan or racoon2 for interop testig
* ipsec.secret files - if non-default configurations are used. also uses the host syntax, eg west.secrets, east.secrets.
* An init.sh file for each VM that needs to start (eg westinit.sh, eastinit.sh, etc)
* One run.sh file for the host that is the initiator (eg westrun.sh)
* Known good (sanitized) output for each VM (eg west.console.txt, east.console.txt)
* testparams.sh if there are any non-default test parameters


You can run this test case by issuing the following command on the host:
* in batch mode <tt>pluto</tt> is shutdown at the end of the test
: this way additional post-mortem checks, such as for memory leaks and core dumps that rely on <tt>pluto</tt> being stopped, can be performed
* in single test mode the system is left running
: this way it is possible to log in and look around the running system and attach a debugger to <tt>pluto</tt> before it is shutdown


Either:
To instead force post-mortem, add:


<pre>
KVMRUNNER_FLAGS += --run-post-mortem
make kvm-test KVM_TESTS+=testing/pluto/basic-pluto-01/
</pre>


or:
to <tt>Makefile.inc.local</tt>.


<pre>
=== Working on individual tests ===
./testing/utils/kvmtest.py testing/pluto/basic-pluto-01
</pre>


multiple tests can be selected with:
The <tt>modified</tt> command can be used to limit the test run to just tests with modified files (according to git):


<pre>
; ./kvm modified install check diff
make kvm-test KVM_TESTS+=testing/pluto/basic-pluto-*
: install libreswan and then run the testsuite against just the modified tests, display differences differences
</pre>
; ./kvm modified recheck diff
: re-run the modified tests that are failing, display differences
; ./kvm modified patch add
: update the modified tests applying the latest output and add them to git


or:
this workflow comes into its own, when updating tests en-mass using sed, for instance:


<pre>
sed -i -e 's/PARENT_//' testing/pluto/*/*.console.txt
./testing/utils/kvmresults.py testing/pluto/basic-pluto-*
./kvm modified check
</pre>


Once the test run has completed, you will see an OUTPUT/ directory in the test case directory:
=== Comparing results to a baseline ===


<pre>
Note: since all "good" tests should pass, this workflow is largely redundant.
$ ls OUTPUT/
east.console.diff  east.console.verbose.txt  RESULT      west.console.txt          west.pluto.log
east.console.txt  east.pluto.log            swan12.pcap  west.console.diff  west.console.verbose.txt
</pre>


* RESULT is a text file (whose format is sure to change in the next few months) stating whether the test succeeded or failed.
Start by setting up a baseline directoryGive the KVMs unique bN prefixes (only "b1" is needed, but we're in a hurry so add "b2 b3 b4", 4 boot workers, and /tmp/pool for KVM disk images) and kick off a test run:
* The diff files show the differences between this testrun and the last known good output.
* Each VM's serial (sanitized) console log (eg west.console.txt)
* Each VM's unsanitized verbose console output (eg west.console.verbose.txt)
* A network capture from the bridge device (eg swan12.pcap)
* Each VM's pluto log, created with plutodebug=all (eg west.pluto.log)
* Any core dumps generated if a pluto daemon crashed


== Debugging inside the VM ==
$ git clone https://github.com/libreswan/libreswan baseline
$ cd baseline
baseline$ # baseline - use bN as the prefix
baseline$ echo KVM_PREFIXES=b1 b2 b3 b4 >> base/Makefile.inc.local
baseline$ echo KVM_WORKERS=4            >> base/Makefile.inc.local
baseline$ echo KVM_LOCALDIR=/tmp/pool  >> base/Makefile.inc.local
baseline$ mkdir -p ../pool
baseline$ nohup ./kvm install check &
baseline$ tail -f nohup.out


=== Debugging pluto on east ===
Next, set up a working directory.  This time the KVMs are given the unique wN prefix, and point KVM_BASELINE back at the baseline/ directory:
 
$ git clone https://github.com/libreswan/libreswan work
$ cd work
work$ # work - use wN as the prefix
work$ echo KVM_PREFIXES=w1 w2 w3 w4 >> work/Makefile.inc.local
work$ echo KVM_WORKERS=4            >> work/Makefile.inc.local
work$ echo KVM_BASELINE=../baseline >> work/Makefile.inc.local
work$ echo KVM_LOCALDIR=/tmp/pool  >> work/Makefile.inc.local
work$ mkdir -p ../pool
 
work then then progress in the work directory, and when ready the test run started (here in the background):
 
work$ ed programs/pluto/plutomain.c
/static bool selftest_only = false/ s/false/true/
w
q
work$ gmake && nohup ./kvm install check &
 
as the tests progress, the results can be monitored:
 
work$ ./kvm baseline results
testing/pluto/basic-pluto-01 failed east:baseline-passed,output-different west:baseline-passed,output-different
...
work$ ./kvm baseline diffs testing/pluto/basic-pluto-01
+whack: Pluto is not running (no "/run/pluto/pluto.ctl")
 
and then the test run aborted, and the problem fixed and tested, and the test run restarted:
 
work$ ./kvm kill
work$ git checkout -- programs/pluto/plutomain.c
work$ ./kvm install check diff testing/pluto/basic-pluto-01
work$ nohup recheck &
 
The output can be fine tuned using baseline-failed (show differences when the baseline failed, ignoring passed and unresolved) baseline-passed (show differences when the baseline passed, ignoring failed and unresolved).
 
To override the KVM_BASELINE make variable, use <tt>--baseline DIRECTORY</tt>
 
=== Controlling a test run remotely ===
 
Start the testsuite in the background:
 
nohup ./kvm install check &
 
To determine if the testsuite is still running:
 
./kvm status
 
and to stop the running testsuite:
 
./kvm kill
 
=== Debugging inside the VM (pluto on east) ===


Terminal 1 - east: log into east, start pluto, and attach gdb
Terminal 1 - east: log into east, start pluto, and attach gdb


<pre>
./kvm sh east
make kvmsh-east
east# cd /testing/pluto/basic-pluto-01
east# cd /testing/pluto/basic-pluto-01
east# sh -x ./eastinit.sh
east# sh -x ./eastinit.sh
east# gdb /usr/local/libexec/ipsec/pluto $(pidof pluto)
east# gdb /usr/local/libexec/ipsec/pluto $(pidof pluto)
(gdb) c
(gdb) c
 
</pre>
If pluto isn't running then gdb will complain with: ''<code>--p requires an argument</code>''


Terminal 2 - west: log into west, start pluto and the test
Terminal 2 - west: log into west, start pluto and the test


<pre>
./kvm sh west
make kvmsh-west
west# sh -x ./westinit.sh ; sh -x westrun.sh
west# sh -x ./westinit.sh ; sh -x westrun.sh
 
</pre>
When pluto crashes, gdb will show that and await commands.  For example, the <tt>bt</tt> command will show a backtrace.
If pluto wasn't running, gdb would complain: ''<code>--p requires an argument</code>''
 
TODO:
 
* stop watchdog eventually killing pluto
* notes for west
 
=== Installing a custom Fedora kernel ===
 
Assuming the kernel RPMs are in the directory <tt>$(KVM_POOLDIR)/kernel-ipsec/ say, add the following to <tt>Makefile.inc.local</tt>:
KVM_FEDORA_KERNEL_RPMDIR = /pool/kernel-ipsec/
KVM_FEDORA_KERNEL_ARCH = x86_64
KVM_FEDORA_KERNEL_VERSION = -5.18.7-100.aiven_ipsec.fc35.$(KVM_FEDORA_KERNEL_ARCH).rpm
and then run:
./kvm upgrade-fedora
(should, like for NetBSD do this during transmogrify?)
 
=== Installing a custom NetBSD kernel ===
 
Copy the kernel to:
$(KVM_POOLDIR)/$(KVM_PREFIX)netbsd-kernel
and then run:
./kvm transmogrify-netbsd
 
=== Building and testing an old branch ===
 
Old branches have two problems:
 
* the KVM codebase is out-of-date
* the OS releases are gone
 
Here are two ways to get around it:
 
==== Using a test-bench ====
 
This workflow works best when working on an old branch (lets say v4.11)
 
Two repositories are used:
 
# repo under test aka <tt>RUTDIR</tt>
#: this contains both the sources and the tests
# <tt>testbench</tt>
#: this contains the test scripts used to drive <tt>${RUT}</tt>
 
Start by checking out the two repositories (existing repositories can also be used, carefully):
 
RUTDIR=$PWD/v4_maint ; export RUTDIR
git clone https://github.com/libreswan/libreswan.git -r v4_maint ${RUTDIR}
git clone https://github.com/libreswan/libreswan.git testbench
 
Next, configure <tt>testbench</tt> so that it compiles, installs, and runs tests from <tt>${RUTDIR}</tt> by setting the <tt>$(KVM_RUTDIR)</tt> make variable:
 
echo KVM_RUTDIR=$(realpath $RUTDIR)          >> testbench/Makefile.inc.local
 
(<tt>$(KVM_SOURCEDIR)</tt> and <tt>$(KVM_TESTINGDIR)</tt> default to <tt>$(KVM_RUTDIR)</tt>; you can also set $(KVM_SOURCEDIR)</tt> and <tt>$(KVM_TESTINGDIR)</tt> explicitly).
 
Now, (re-)transmogrify the <tt>testbench</tt> so that, within the domains, <tt>/source</tt> points at <tt>${RUT}</tt> and <tt>/testing</tt> points at <tt>${RUT}/testing</tt>:
 
./testbench/kvm transmogrify
 
in the command building the fedora domain look for output like:
 
--filesystem=target=bench,type=mount,accessmode=squash,source=/.../testbench \
--filesystem=target=source,type=mount,accessmode=squash,source=${RUTDIR} \
--filesystem=target=testing,type=mount,accessmode=squash,source=${RUTDIR}/testing \
 
Finally install and then run a test:
 
./testbench/kvm install check diff $RUT/testing/pluto/basic-pluto-01
 
If you prefer you can run <tt>testbench/kvm</tt>:
 
* from the <tt>testbench</tt> directory as <tt>./kvm</tt>
* from the <tt>${RUTDIR}</tt> directory as <tt>../testbench/kvm</tt>
 
just do not run $RUTDIR/kvm.
 
==== Reviving the dead OS ====
 
Again looking at v4_maint branch.  Check it out:
 
  git checkout ... -b v4_maint
 
add the following to Makefile.inc.local:
 
  KVM_PREFIX=v4
  KVM_FEDORA_ISO_URL = https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Server/x86_64/iso/Fedora-Server-dvd-x86_64-35-1.2.iso
 
build fedora-base:
 
  ./kvm base-fedora
 
login to the base domain:
 
  ./kvm sh fedora-base
 
and edit the repos per:
 
  /etc/yum.repos.d/fedora.repo:name=Fedora $releasever - $basearch
  /etc/yum.repos.d/fedora.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Everything/x86_64/os
  /etc/yum.repos.d/fedora.repo:name=Fedora $releasever - $basearch - Debug
  /etc/yum.repos.d/fedora.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Everything/x86_64/debug/tree/
  /etc/yum.repos.d/fedora.repo:name=Fedora $releasever - Source
  /etc/yum.repos.d/fedora.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Everything/source/tree/
  /etc/yum.repos.d/fedora-updates.repo:name=Fedora $releasever - $basearch - Updates
  /etc/yum.repos.d/fedora-updates.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/updates/35/Everything/x86_64/
  /etc/yum.repos.d/fedora-updates.repo:name=Fedora $releasever - $basearch - Updates - Debug
  /etc/yum.repos.d/fedora-updates.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/updates/35/Everything/x86_64/debug/
  /etc/yum.repos.d/fedora-updates.repo:name=Fedora $releasever - Updates Source
  /etc/yum.repos.d/fedora-updates.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/updates/35/Everything/source/tree/
 
after that:
 
  ./kvm install check
 
might work
 
=== Tracking down regressions (using git bisect) ===
 
==== The easy way ====
 
This workflow works best when the regression is recent (i.e., the last few commits) and nothing significant has happened in the meantime (for instance, os upgrade, test rename, ...).
 
The command <tt>./kvm install check diff</tt> exits with a <tt>git bisect</tt> friendly status codes which means it can be combined with <tt>git bisect run</tt> to automate regression testing.
 
For instance:
 
git bisect start main ^<suspect-commit>
git bisect run ./kvm install check diff testing/pluto/basic-pluto-01
git bisect visualize
# finally
git bisect reset
 
==== The hard way ====
 
This workflow works best when trying to track down a regression in an older version of libreswan.
 
Two repositories are used:
 
#  <tt>repo-under-test</tt>
#: this contains the sources that will be built and installed into the test domains and is what git bisect will manipulate
# <tt>testbench</tt>
#: this contains the test scripts used to drive <tt>repo-under-test</tt>


When pluto crashes, gdb will show that and await commands.  For example, the bt command will show a backtrace.
Start by checking out the two repositories (existing repositories can also be used, carefully):


=== Debugging pluto on west ===
git clone https://github.com/libreswan/libreswan.git repo-under-test
git clone https://github.com/libreswan/libreswan.git testbench


See above, but also use virt as a terminal.
and then cd to the <tt>repo-under-test</tt> directory:


=== /root/.gdbinit ===
  cd repo-under-test


If you want to get rid of the warning "warning: File "/testing/pluto/ikev2-dpd-01/.gdbinit" auto-loading has been declined by your `auto-load safe-path'"
Next, configure <tt>testbench</tt> so that it compiles and installs libreswan from <tt>repo-under-test</tt> but runs tests from <tt>testbench</tt>. Do this by pointing the <tt>testbench</tt> <tt>KVM_SOURCEDIR</tt> (<tt>/source</tt>) at <tt>repo-under-test</tt> vis:


<pre>
# remember $PWD is repo-under-test
echo "set auto-load safe-path /" >> /root/.gdbinit
echo KVM_SOURCEDIR=$(realpath ../repo-under-test)    >>../testbench/Makefile.inc.local
</pre>
echo KVM_TESTINGDIR=$(realpath ../testbench/testing) >>../testbench/Makefile.inc.local


== Updating the VMs ==
Now, (re-)transmogrify the <tt>testbench</tt> so that, within the domains, <tt>/source</tt> points at <tt>repo-under-test</tt>:


# delete all the copies of the base VM:
../testbench/kvm transmogrify
#: <tt>$ make kvm-purge</tt>
# install again
#: <tt>$ make kvm-install</tt>


== Publishing Results on the web: http://testing.libreswan.org/results/ ==
in the command building the fedora domain look for output like:


This is experimental and uses:
--filesystem=target=bench,type=mount,accessmode=squash,source=/.../testbench \
--filesystem=target=source,type=mount,accessmode=squash,source=/.../repo-under-test \
--filesystem=target=testing,type=mount,accessmode=squash,source=/.../testbench/testing \


* CSS
Finally run the tests (remember testing/pluto/basic-pluto-01 is the test that started failing):
* javascript


Two scripts are available:
# start with the bad commit
git bisect start main
# next checkout and confirm the good commit
# NOTE: run testbench/kvm from repo-under-test directory
git checkout <good-commit>
../testbench/kvm install check diff testing/pluto/basic-pluto-01
git bisect good


* <tt>testing/web/setup.sh</tt>
if you're lucky, the test requires no manual intervention and:
: sets up the directory <tt>~/results</tt> adding any dependencies
* <tt>testing/web/publish.sh</tt>
: runs the testsuite and then copies the results to <tt>~/results</tt>


To view this, use file:///.
git bisect run ../testbench/kvm install check diff testing/pluto/basic-pluto-01


To get this working with httpd (Apache web server):
also works:


<pre>
# finally
sudo systemctl enable httpd
git bisect visualize
sudo systemctl start httpd
git bisect reset
sudo ln -s ~/results /var/www/html/
sudo sh -c 'echo "AddType text/plain .diff" >/etc/httpd/conf.d/diff.conf'
</pre>


To view the results, use http://localhost/results.
TODO: figure out how to get ../testbench/kvm diff to honour KVM_TESTINGDIR so that it can handle a test somewhere other than in <tt?testbench</tt>

Latest revision as of 18:59, 20 December 2023

KVM Test framework

Libreswan's test framework can be run using KVM guests, and the kvm scripts. It is strongly recommended to run the test suite on a host machine that has a CPU wth virtualisation instructions.

To access files on the host file system:

  • Linux guests (Fedora) use the PLAN9 filesystem (9p)
  • BSD guests (FreeBSD, NetBSD, OpenBSD) use NFS via the NAT interface

For an overview of the tests see Test_Suite

Preparing the host machine

Check Virtualization is enabled in the BIOS

Virtualization needs to be enabled by the BIOS during boot.

 grep -e vmx -e svm /proc/cpuinfo

Add yourself to sudo

Some of the test scrips need to be run as root. The test environment assumes this can be done using sudo without a password vis:

sudo pwd

XXX: Surely qemu can be driven without root?

This is setup by adding an entry under /etc/sudoers.d/ specifying that your account does not need a password to become root:

echo "$(id -u -n) ALL=(ALL) NOPASSWD: ALL" | sudo dd of=/etc/sudoers.d/$(id -u -n)

Fight SELinux

SELinux blocks some actions that we need. We have not created any SELinux rules to avoid this. The options are:

  • set SELinux to permissive (recommended)
sudo sed --in-place=.ORIG -e 's/^SELINUX=.*/SELINUX=permissive/' /etc/selinux/config
sudo setenforce Permissive
  • disable SELinux
sudo sed --in-place=.ORIG -e 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config
sudo reboot
  • (experimental) label source tree for SELinux

The source tree on the host is shared with the virtual machines. SELinux considers this a bug unless the tree is labelled with type svirt_image_t.

sudo dnf install policycoreutils-python-utils
sudo semanage fcontext -a -t svirt_image_t "$(pwd)"'(/.*)?'
sudo restorecon -vR /home/build/libreswan

There may be other things that SELinux objects to.

Check that the host has enough entropy

As a rough guide run:

while true ; do cat /proc/sys/kernel/random/entropy_avail ; sleep 3 ; done

it should have values in the hundrets if not thousands. If it is in the units or tens then see Entropy matters

Install Dependencies

Why Fedora Mint (debian)
Basics sudo dnf install -y make git gitk patch sudo apt-get install -y make make-doc git gitk
Python sudo dnf install -y python3-pexpect sudo apt-get install python3-pexpect
Virtulization sudo dnf install -y qemu virt-install libvirt-daemon-kvm libvirt-daemon-qemu sudo apt install -y qemu virtinst libvirt-clients libvirt-daemon libvirt-daemon-system libvirt-daemon-driver-qemu libosinfo-query qemu-system-x86?
Boot CDs sudo dnf install -y dvd+rw-tools sudo apt-get install -y dvd+rw-tools
Web Pages sudo dnf install -y jq nodejs-typescript sudo apt-get install -y jq node-typescript
Web Server (optional) sudo dnf install -y httpd sudo apt-get install -y ????
NFS sudo dnf install -y nfs-utils # ??? sudo apt-get install -y nfs-kernel-server rpcbind
Broken makefiles sudo dnf install -y nss-devel # make file invokes pkg-config nss

Enable libvirt

If you're switching from the old libvirtd see https://libvirt.org/daemons.html#switching-to-modular-daemons for how to shut down the old daemons.

Start the "collection of modular daemons that replace functionality previously provided by the monolithic libvirtd daemon":

for drv in qemu network nodedev nwfilter secret storage interface
do
   sudo systemctl unmask virt${drv}d.service
   sudo systemctl unmask virt${drv}d{,-ro,-admin}.socket
   sudo systemctl enable virt${drv}d.service
   sudo systemctl enable virt${drv}d{,-ro,-admin}.socket
done
for drv in qemu network nodedev nwfilter secret storage
do
   sudo systemctl start virt${drv}d{,-ro,-admin}.socket
done

There should be no errors and warnings.

Stop libvirt daemons shutting down

By default the libvirt daemons timeout and shutdown after 120 seconds (surely systemd will restart them!). It turns out this hasn't worked so well:

systemd doesn't restart the daemon
the restart is painfully slow with lots of networks which causes the timeout

Disabling the timeout and just leaving the daemons running seems to help. Add the following:

 echo VIRTNETWORKD_ARGS= > /etc/sysconfig/virtnetworkd
 echo VIRTQEMUD_ARGS= > /etc/sysconfig/virtqemud
 echo VIRTSTORAGED_ARGS= > /etc/sysconfig/virtstoraged

the standard libvirt systemd config files read these settings using EnvironmentFile=

Add yourself to the KVM/QEMU group

You need to add yourself to the group that QEMU/KVM uses when writing to /var/lib/libvirt/qemu. On Fedora it is 'qemu', and on Debian it is 'kvm'. Something like:

sudo usermod -a -G $(stat --format %G /var/lib/libvirt/qemu) $(id -u -n)

After this you will will need to re-login (or run sudo su - $(id -u -n)

Make certain that root can access the build

The path to your build needs to be accessible (executable) by root, assuming things are under home:

chmod a+x $HOME

Fix /var/lib/libvirt/qemu

sudo chmod g+w /var/lib/libvirt/qemu

Arguably we should run libvirt as a normal user instead.

Create /etc/modules-load.d/virtio.conf (obsolete since 2022 at least)

Several virtio modules need to be loaded into the host's kernel. This could be done by modprobe ahead of running any virtual machines but it is easier to install them whenever the host boots. This is arranged by listing the modules in a file within /etc/modules-load.d. The host must be rebooted for this to take effect.

sudo dd <<EOF of=/etc/modules-load.d/virtio.conf
virtio_blk
virtio-rng
virtio_console
virtio_net
virtio_scsi
virtio
virtio_balloon
virtio_input
virtio_pci
virtio_ring
9pnet_virtio
EOF

As of Fedora 28, several of these modules are built into the kernel and will not show up in /proc/modules (virtio, virtio_rng, virtio_pci, virtio_ring).

Set up a Web Server (optional)

If the machine is to run nightly test runs then it can be set up as a web server. See the nightly test results for an example.

See above for dependencies. See below for how to configure libreswan.

To set up the server:

sudo mkdir /var/www/html/results/
sudo chown $(id -un) /var/www/html/results/
sudo chmod 755 /var/www/html/results/
sudo sh -c 'echo "AddType text/plain .diff" >/etc/httpd/conf.d/diff.conf'

to run the web server until the next reboot:

sudo firewall-cmd --add-service=http
sudo systemctl start httpd

to make the web server permanent:

sudo systemctl enable httpd
sudo firewall-cmd --add-service=http --permanent

If you want it to be the main page of the website, you can create the file /var/www/html/index.html containing:

cat <<EOF
 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
   <head>
     <meta http-equiv="REFRESH" content="0;url=/results/">
  </head>
   <BODY>
  </BODY>
 </HTML>
 
EOF

Debian

On Debian slack based systems (i.e., Linux Mint 20.3), the default python is too old. Fortunately python 3.9 is also available vis:

sudo apt-get install python3.9

in addition, the make variable KVM_PYTHON will need to be added to Makefile.inc.local, see below.

BSD

Anyone?

Download and configure libreswan

Fetch Libreswan

The libreswan source tree includes all the components that are used on the host and inside the test VMs. To get the latest source code using git:

git clone https://github.com/libreswan/libreswan
cd libreswan

Developers can use Makefile.inc.local to override default build setttings. Create the file:

touch Makefile.inc.local

(packaging systems should not use this, and instead explicitly pass the make variables to the make command)

(optional) Override python

See above. If pthon isn't new enough (for instance on Debian) set KVM_PYTHON in Makefile.inc.local vis:

echo KVM_PYTHON=python3.9 >> Makefile.inc.local

Create the Pool directory for storing VM disk images - $(KVM_POOLDIR)

The pool directory is used used to store:

  • VM disk images
  • install CD/DVD images
  • downloaded packages installed into the VMs
  • other files

and can get quite large. It can and should be shared between build trees (this reflects libvirt which has a single name space for domains). KVM_PREFIXES (see further down) addresses the lack of name spaces.

By default $(top_srcdir)/../pool (../pool) is used (that is, adjacent to your source tree). It will need to be created.

Alternatively the shared pool directory can be specified explicitly by setting the make variable KVM_POOLDIR in Makefile.inc.local vis:

mkdir KVM_POOLDIR=/home/libreswan/pool
echo KVM_POOLDIR=/home/libreswan/pool >> Makefile.inc.local

(optional) Use /tmp/pool (tmpfs) to store test VM disk images - $(KVM_LOCALDIR)

By default, all disk mages are stored in $(KVM_POOLDIR) (see above). Since the test VM disk images do not need long-term storage (i.e., survive a reboot), $(KVM_LOCALDIR) can be used to specify that test VM disk images are stored in /tmp vis:

echo KVM_LOCALDIR=/tmp/pool >> Makefile.inc.local

This has the advantage of eliminating physical disk I/O as a bottle neck when accessing VM disk images; but the disadvantage of needing to re-build the test disk images after a reboot.

(optional) Define test groups and run tests in parallel - $(KVM_PREFIXES)

By default there is only one set of build and test domains. This means that a host can only support one build tree, and that tests are run sequentially.

This can be changed by setting the KVM_PREFIXES make variable in Makefile.inc.local. This specifies a list of prefixes to be pretended to build and test domains creating multiple test groups.

The default value is:

KVM_PREFIXES=

which creates the build domains fedora-base, fedora-upgrade, fedora, et.al., and the test domains east, west, et.al. (i.e., after expansion fedora-base, fedora-upgrade, fedora, east, west, et.al.).

To run tests in parallel and assign unique domains to the build directory, specify multiple prefixes. For instance a build tree can be given unique domains and run two tests in parallel by specifying:

KVM_PREFIXES=t1 t2

This will create the build domains t1fedora-base, t1fedora-upgrade, t1fedora, et.al., and the test domains t1east, t2east, et.al.

Due to limitations in the network stack (networks with prefix t. and t2. are also created) the prefix needs to be short.

(optional) Parallel builds - $(KVM_WORKERS)

By default, build domains only have on virtual CPU. Since building is very CPU intensive, this can be increased using $(KVM_WORKERS).

KVM_WORKERS=2

(optional) Generate a web page of the test results

See the nightly test results for an example and how to set up a web server so results can be viewed remotely.

To initially create the web directory RESULTS/ and populate it with the current test results use:

make web

Further test runs will update the RESULTS/ directory. The files can the be viewed using http://file.

To disable web page generation, delete the directory RESULTS/.

To instead publish the results on the web, point $(WEB_SUMMARYDIR) at the web directory:

$ WEB_SUMMARYDIR=/var/www/html/results >> Makefile.inc.local

Running the testsuite

In the past, the testsuite was driven using make kvm-... commands. That's largely been replaced by the top-level wrapper script ./kvm which has several advantages over make:

  • it is file (file) completion friendly
  • it is shell script friendly

For the impatient: ./kvm install check

To build the VMs, and build and install (or update) libreswan, and then run the tests, use:

./kvm install check

Setting up ./kvm (tab completion)

If this:

complete -o filenames -C './kvm' ./kvm

is added to .bashrc then tab completion with ./kvm will include both commands and directories.

Running the testsuite

./kvm install
update the KVMs ready for a new test run
./kvm check
run the testsuite, previous results are saved in BACKUP/-date-
./kvm recheck
run the testsuite, but skip tests that already passed
./kvm results
list the results from the test run
./kvm diffs
display differences between the test results and the expected results, exit non-zero if there are any

the operations can be combined on a single line:

./kvm install check recheck diff

and individual tests can be selected (see Running a Single Test, below):

./kvm install check diff testing/pluto/*ikev2*

To stop ./kvm use control-c.

Updating Certificates

The full testsuite requires a number of certificates. If not present, then ./kvm check will automatically generate them using the domain build. Just note that the certificates have a limited lifetime. Should the test system detects out-of-date certificates then ./kvm check will barf.

To rebuild the certificates:

./kvm keys

can be used to force the generation of new certificates.

Cleaning up (and general maintenance)

./kvm check-clean
delete the test results
./kvm uninstall
delete the KVM build and test domains (but don't touch the build tree or test results)
./kvm clean
delete the test results, the KVM build and test domains, the build tree, and the certificates
./kvm purge
also delete the test networks (is purge still useful?)
./kvm demolish
also delete the KVM base domain that was used to create the other domains
./kvm upgrade
delete all KVM build and test domains, and then upgrade and transmogrify the base domain ready for a fresh install
./kvm transmogrify
run a fresh transmogrify on the base domain (the base domain is reverted to before the last transmogrify)
./kvm downgrade
revert the base domain back to before it was upgraded (useful when debugging upgrade and transmogrify)

Shell and Console Access (Logging In)

There are several different ways to gain shell access to the domains.

Each method, depending on the situation, has both advantages and disadvantages. For instance:

  • while make kvmsh-host provide quick access to the console, it doesn't support file copy
  • while SSH takes more to set up, it supports things like proper terminal configuration and file copy

Serial Console access using ./kvm sh HOST (kvmsh.py)

./kvm sh HOST is a wrapper around "virsh" that automatically handles things like booting the machine, logging in, and correctly configuring the terminal. It's big advantage is that it always works. For instance:

$ ./testing/utils/kvmsh.py east
[...]
Escape character is ^]
[root@east ~]# printenv TERM
xterm
[root@east ~]# stty -a
...; rows 52; columns 185; ... 
[root@east ~]#

The script "kvmsh.py" can also be used directly to invoke commands on a guest (this is how ./kvm install works):

$ ./testing/utils/kvmsh.py east ls
[root@east ~]# ls
anaconda-ks.cfg

When $(KVM_PREFIXES) contains multiple prefixes, ./kvm sh east always logs into the first prefixe's domain.

Limitations:

  • no file transfer but files can be accessed via /pool and /testing

Graphical Console access using virt-manager

"virt-manager", a gnome tool can be used to access individual domains.

While easy to use, it doesn't support cut/paste or mechanisms for copying files.

Shell access using SSH

While requiring more effort to set up, it provides full shell access to the domains.

Since you will be using ssh a lot to login to these machines, it is recommended to either put their names in /etc/hosts:

# /etc/hosts entries for libreswan test suite
192.1.2.45 west
192.1.2.23 east
192.0.3.254 north
192.1.3.209 road
192.1.2.254 nic

or add entries to .ssh/config such as:

Host west
       Hostname 192.1.2.45

If you wish to be able to ssh into all the VMs created without using a password, add your ssh public key to testing/baseconfigs/all/etc/ssh/authorized_keys. This file is installed as /root/.ssh/authorized_keys on all VMs

Using ssh becomes easier if you are running ssh-agent (you probably are) and your public key is known to the virtual machine. This command, run on the host, installs your public key on the root account of the guest machines west. This assumes that west is up (it might not be, but you can put this off until you actually need ssh, at which time the machine would need to be up anyway). Remember that the root password on each guest machine is "swan".

ssh-copy-id root@west

You can use ssh-copy for any VM. Unfortunately, the key is forgotten when the VM is restarted.

Limitations:

  • this only works with the default east, et.al. (it does not work with KVM_PREFIXES and/or multiple test directories)

kvm workflows

(seeing as everyone has a "flow", why not kvm) here are some common workflows, the following commands are used:

./kvm modified
list the test directories that have been modified
./kvm baseline
compare test results against a baseline
./kvm patch
update the expected test results
./kvm add
git add the modified test results
./kvm status
show the status of the currently running testsuite
./kvm kill
kill the currently running testsuite

Running a single test

There are two ways to run an individual test:

  1. the test to run can be specified on the command line:
    kvm check testing/pluto/basic-pluto-01
  2. the test is implied when running kvm from a test directory:
    cd testing/pluto/basic-pluto-01
    ../../../kvm
    ../../../kvm diff

But there's a catch:

  • in batch mode pluto is shutdown at the end of the test
this way additional post-mortem checks, such as for memory leaks and core dumps that rely on pluto being stopped, can be performed
  • in single test mode the system is left running
this way it is possible to log in and look around the running system and attach a debugger to pluto before it is shutdown

To instead force post-mortem, add:

KVMRUNNER_FLAGS += --run-post-mortem

to Makefile.inc.local.

Working on individual tests

The modified command can be used to limit the test run to just tests with modified files (according to git):

./kvm modified install check diff
install libreswan and then run the testsuite against just the modified tests, display differences differences
./kvm modified recheck diff
re-run the modified tests that are failing, display differences
./kvm modified patch add
update the modified tests applying the latest output and add them to git

this workflow comes into its own, when updating tests en-mass using sed, for instance:

sed -i -e 's/PARENT_//' testing/pluto/*/*.console.txt
./kvm modified check

Comparing results to a baseline

Note: since all "good" tests should pass, this workflow is largely redundant.

Start by setting up a baseline directory. Give the KVMs unique bN prefixes (only "b1" is needed, but we're in a hurry so add "b2 b3 b4", 4 boot workers, and /tmp/pool for KVM disk images) and kick off a test run:

$ git clone https://github.com/libreswan/libreswan baseline
$ cd baseline
baseline$ # baseline - use bN as the prefix
baseline$ echo KVM_PREFIXES=b1 b2 b3 b4 >> base/Makefile.inc.local
baseline$ echo KVM_WORKERS=4            >> base/Makefile.inc.local
baseline$ echo KVM_LOCALDIR=/tmp/pool   >> base/Makefile.inc.local
baseline$ mkdir -p ../pool
baseline$ nohup ./kvm install check &
baseline$ tail -f nohup.out

Next, set up a working directory. This time the KVMs are given the unique wN prefix, and point KVM_BASELINE back at the baseline/ directory:

$ git clone https://github.com/libreswan/libreswan work
$ cd work
work$ # work - use wN as the prefix
work$ echo KVM_PREFIXES=w1 w2 w3 w4 >> work/Makefile.inc.local
work$ echo KVM_WORKERS=4            >> work/Makefile.inc.local
work$ echo KVM_BASELINE=../baseline >> work/Makefile.inc.local
work$ echo KVM_LOCALDIR=/tmp/pool   >> work/Makefile.inc.local
work$ mkdir -p ../pool

work then then progress in the work directory, and when ready the test run started (here in the background):

work$ ed programs/pluto/plutomain.c
/static bool selftest_only = false/ s/false/true/
w
q
work$ gmake && nohup ./kvm install check &

as the tests progress, the results can be monitored:

work$ ./kvm baseline results
testing/pluto/basic-pluto-01 failed east:baseline-passed,output-different west:baseline-passed,output-different
...
work$ ./kvm baseline diffs testing/pluto/basic-pluto-01
+whack: Pluto is not running (no "/run/pluto/pluto.ctl")

and then the test run aborted, and the problem fixed and tested, and the test run restarted:

work$ ./kvm kill
work$ git checkout -- programs/pluto/plutomain.c
work$ ./kvm install check diff testing/pluto/basic-pluto-01
work$ nohup recheck &

The output can be fine tuned using baseline-failed (show differences when the baseline failed, ignoring passed and unresolved) baseline-passed (show differences when the baseline passed, ignoring failed and unresolved).

To override the KVM_BASELINE make variable, use --baseline DIRECTORY

Controlling a test run remotely

Start the testsuite in the background:

nohup ./kvm install check &

To determine if the testsuite is still running:

./kvm status

and to stop the running testsuite:

./kvm kill

Debugging inside the VM (pluto on east)

Terminal 1 - east: log into east, start pluto, and attach gdb

./kvm sh east
east# cd /testing/pluto/basic-pluto-01
east# sh -x ./eastinit.sh
east# gdb /usr/local/libexec/ipsec/pluto $(pidof pluto)
(gdb) c

If pluto isn't running then gdb will complain with: --p requires an argument

Terminal 2 - west: log into west, start pluto and the test

./kvm sh west
west# sh -x ./westinit.sh ; sh -x westrun.sh

When pluto crashes, gdb will show that and await commands. For example, the bt command will show a backtrace.

TODO:

  • stop watchdog eventually killing pluto
  • notes for west

Installing a custom Fedora kernel

Assuming the kernel RPMs are in the directory $(KVM_POOLDIR)/kernel-ipsec/ say, add the following to Makefile.inc.local:

KVM_FEDORA_KERNEL_RPMDIR = /pool/kernel-ipsec/
KVM_FEDORA_KERNEL_ARCH = x86_64
KVM_FEDORA_KERNEL_VERSION = -5.18.7-100.aiven_ipsec.fc35.$(KVM_FEDORA_KERNEL_ARCH).rpm

and then run:

./kvm upgrade-fedora

(should, like for NetBSD do this during transmogrify?)

Installing a custom NetBSD kernel

Copy the kernel to:

$(KVM_POOLDIR)/$(KVM_PREFIX)netbsd-kernel

and then run:

./kvm transmogrify-netbsd

Building and testing an old branch

Old branches have two problems:

  • the KVM codebase is out-of-date
  • the OS releases are gone

Here are two ways to get around it:

Using a test-bench

This workflow works best when working on an old branch (lets say v4.11)

Two repositories are used:

  1. repo under test aka RUTDIR
    this contains both the sources and the tests
  2. testbench
    this contains the test scripts used to drive ${RUT}

Start by checking out the two repositories (existing repositories can also be used, carefully):

RUTDIR=$PWD/v4_maint ; export RUTDIR
git clone https://github.com/libreswan/libreswan.git -r v4_maint ${RUTDIR}
git clone https://github.com/libreswan/libreswan.git testbench

Next, configure testbench so that it compiles, installs, and runs tests from ${RUTDIR} by setting the $(KVM_RUTDIR) make variable:

echo KVM_RUTDIR=$(realpath $RUTDIR)           >> testbench/Makefile.inc.local

($(KVM_SOURCEDIR) and $(KVM_TESTINGDIR) default to $(KVM_RUTDIR); you can also set $(KVM_SOURCEDIR) and $(KVM_TESTINGDIR) explicitly).

Now, (re-)transmogrify the testbench so that, within the domains, /source points at ${RUT} and /testing points at ${RUT}/testing:

./testbench/kvm transmogrify

in the command building the fedora domain look for output like:

--filesystem=target=bench,type=mount,accessmode=squash,source=/.../testbench \
--filesystem=target=source,type=mount,accessmode=squash,source=${RUTDIR} \
--filesystem=target=testing,type=mount,accessmode=squash,source=${RUTDIR}/testing \

Finally install and then run a test:

./testbench/kvm install check diff $RUT/testing/pluto/basic-pluto-01

If you prefer you can run testbench/kvm:

  • from the testbench directory as ./kvm
  • from the ${RUTDIR} directory as ../testbench/kvm

just do not run $RUTDIR/kvm.

Reviving the dead OS

Again looking at v4_maint branch. Check it out:

 git checkout ... -b v4_maint

add the following to Makefile.inc.local:

 KVM_PREFIX=v4
 KVM_FEDORA_ISO_URL = https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Server/x86_64/iso/Fedora-Server-dvd-x86_64-35-1.2.iso

build fedora-base:

 ./kvm base-fedora

login to the base domain:

 ./kvm sh fedora-base

and edit the repos per:

 /etc/yum.repos.d/fedora.repo:name=Fedora $releasever - $basearch
 /etc/yum.repos.d/fedora.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Everything/x86_64/os
 /etc/yum.repos.d/fedora.repo:name=Fedora $releasever - $basearch - Debug
 /etc/yum.repos.d/fedora.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Everything/x86_64/debug/tree/
 /etc/yum.repos.d/fedora.repo:name=Fedora $releasever - Source
 /etc/yum.repos.d/fedora.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/35/Everything/source/tree/
 /etc/yum.repos.d/fedora-updates.repo:name=Fedora $releasever - $basearch - Updates
 /etc/yum.repos.d/fedora-updates.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/updates/35/Everything/x86_64/
 /etc/yum.repos.d/fedora-updates.repo:name=Fedora $releasever - $basearch - Updates - Debug
 /etc/yum.repos.d/fedora-updates.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/updates/35/Everything/x86_64/debug/
 /etc/yum.repos.d/fedora-updates.repo:name=Fedora $releasever - Updates Source
 /etc/yum.repos.d/fedora-updates.repo:baseurl=https://archives.fedoraproject.org/pub/archive/fedora/linux/updates/35/Everything/source/tree/

after that:

 ./kvm install check

might work

Tracking down regressions (using git bisect)

The easy way

This workflow works best when the regression is recent (i.e., the last few commits) and nothing significant has happened in the meantime (for instance, os upgrade, test rename, ...).

The command ./kvm install check diff exits with a git bisect friendly status codes which means it can be combined with git bisect run to automate regression testing.

For instance:

git bisect start main ^<suspect-commit>
git bisect run ./kvm install check diff testing/pluto/basic-pluto-01
git bisect visualize
# finally
git bisect reset

The hard way

This workflow works best when trying to track down a regression in an older version of libreswan.

Two repositories are used:

  1. repo-under-test
    this contains the sources that will be built and installed into the test domains and is what git bisect will manipulate
  2. testbench
    this contains the test scripts used to drive repo-under-test

Start by checking out the two repositories (existing repositories can also be used, carefully):

git clone https://github.com/libreswan/libreswan.git repo-under-test
git clone https://github.com/libreswan/libreswan.git testbench

and then cd to the repo-under-test directory:

 cd repo-under-test

Next, configure testbench so that it compiles and installs libreswan from repo-under-test but runs tests from testbench. Do this by pointing the testbench KVM_SOURCEDIR (/source) at repo-under-test vis:

# remember $PWD is repo-under-test
echo KVM_SOURCEDIR=$(realpath ../repo-under-test)    >>../testbench/Makefile.inc.local
echo KVM_TESTINGDIR=$(realpath ../testbench/testing) >>../testbench/Makefile.inc.local

Now, (re-)transmogrify the testbench so that, within the domains, /source points at repo-under-test:

../testbench/kvm transmogrify

in the command building the fedora domain look for output like:

--filesystem=target=bench,type=mount,accessmode=squash,source=/.../testbench \
--filesystem=target=source,type=mount,accessmode=squash,source=/.../repo-under-test \
--filesystem=target=testing,type=mount,accessmode=squash,source=/.../testbench/testing \

Finally run the tests (remember testing/pluto/basic-pluto-01 is the test that started failing):

# start with the bad commit
git bisect start main
# next checkout and confirm the good commit
# NOTE: run testbench/kvm from repo-under-test directory
git checkout <good-commit>
../testbench/kvm install check diff testing/pluto/basic-pluto-01
git bisect good

if you're lucky, the test requires no manual intervention and:

git bisect run ../testbench/kvm install check diff testing/pluto/basic-pluto-01

also works:

# finally
git bisect visualize
git bisect reset

TODO: figure out how to get ../testbench/kvm diff to honour KVM_TESTINGDIR so that it can handle a test somewhere other than in <tt?testbench