Reflect the new default value, and explain that a runtime
lookup will be performed if the value is not an absolute path.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reflect the new default value, and explain that a runtime
lookup will be performed if the value is not an absolute path.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Ideally, we would just pick the best default and users wouldn't
have to intervene at all. But in some cases it may be handy to
not bother with SCHED_CORE at all or place helper processes into
the same group as QEMU. Introduce a knob in qemu.conf to allow
users control this behaviour.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The default values used by the library are determined at configure
time based on a number of factors, and we should reflect them in
the installed configuration file to make the comments it contains
more useful.
Resolves: https://gitlab.com/libvirt/libvirt/-/issues/263
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
New QEMU supports a harsh, but hard to ignore way to notify that the
QMP user used a deprecated command. This is useful e.g. for developers
to see that something needs to be fixed.
This patch introduces a qemu.conf option to enable the setting in cases
when qemu supports it so that developers and continiuous integration
efforts are notified about use of deprecated fields before it's too
late.
The option is deliberately stored as string and not validated to prevent
failures when downgrading qemu or libvirt versions. While we don't
support this, the knob isn't meant for public consumption anyways.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Forgetting to use the VIR_MIGRATE_TLS flag with migration can lead to
leak of sensitive information. Add an administrative knob to force use
of the flag.
Note that without VIR_MIGRATE_PEER2PEER, the migration is driven by an
instance of the client library which doesn't necessarily run on either
of the hosts so the flag can't be used to assume VIR_MIGRATE_TLS even
if it wasn't provided by the user instead of rejecting if it's not.
Resolves: https://gitlab.com/libvirt/libvirt/-/issues/67
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
TLS is required to transport backed-up data securely when using
pull-mode backups.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Until now libvirt didn't allow using encrypted TLS key for disk clients.
Add fields for configuring the secret and propagate defaults.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The RTC and HPET modes for the QEMU emulation tick have been dropped
almost 9 years ago, in commit 25f3151ece1d5881826232bebccc21b588d4e03e.
Do not allow them in the devices cgroup policy.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Add a 'virtiofsd_debug' option for tuning whether to run virtiofsd
in debug mode.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Tested-by: Andrea Bolognani <abologna@redhat.com>
When QEMU uid/gid is set to non-root this is pointless as if we just
used a regular setuid/setgid call, the process will have all its
capabilities cleared anyway by the kernel.
When QEMU uid/gid is set to root, this is almost (always?) never
what people actually want. People make QEMU run as root in order
to access some privileged resource that libvirt doesn't support
yet and this often requires capabilities. As a result they have
to go find the qemu.conf param to turn this off. This is not
viable for libguestfs - they want to control everything via the
XML security label to request running as root regardless of the
qemu.conf settings for user/group.
Clearing capabilities was implemented originally because there
was a proposal in Fedora to change permissions such that root,
with no capabilities would not be able to compromise the system.
ie a locked down root account. This never went anywhere though,
and as a result clearing capabilities when running as root does
not really get us any security benefit AFAICT. The root user
can easily do something like create a cronjob, which will then
faithfully be run with full capabilities, trivially bypassing
the restriction we place.
IOW, our clearing of capabilities is both useless from a security
POV, and breaks valid use cases when people need to run as root.
This removes the clear_emulator_capabilities configuration
option from qemu.conf, and always runs QEMU with capabilities
when root. The behaviour when non-root is unchanged.
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
A slirp helper is a process that provides user-mode networking through
a unix domain socket. It is expected to follow the following
specification:
https://gitlab.freedesktop.org/slirp/libslirp-rs/blob/master/src/bin/README.rst
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Using @VARNAME@ is a normal style of automake, so lets match that.
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Some VM configurations may result in a large number of threads created by
the associated qemu process which can exceed the system default limit. The
maximum number of threads allowed per process is controlled by the pids
cgroup controller and is set to 16k when creating VMs with systemd's
machined service. The maximum number of threads per process is recorded
in the pids.max file under the machine's pids controller cgroup hierarchy,
e.g.
$cgrp-mnt/pids/machine.slice/machine-qemu\\x2d1\\x2dtest.scope/pids.max
Maximum threads per process is controlled with the TasksMax property of
the systemd scope for the machine. This patch adds an option to qemu.conf
which can be used to override the maximum number of threads allowed per
qemu process. If the value of option is greater than zero, it will be set
in the TasksMax property of the machine's scope after creating the machine.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
This reverts commit fc3990c7e6.
Now that all the reported bugs are fixed let's turn the feature
back on.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
In cases when e.g. a new feature breaks upstream behaviour it's useful
to allow users to disable the new feature to verify the regression and
possibly use it as a workaround until a fix is available.
The new qemu.conf option named "capability_filters" allows to remove
qemu capabilities from the detected bitmap.
This patch introduces the configuration infrastructure to parse the
option and pass it around.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We dropped support in commit 8e91a40 (November 2015), but some
occurrences still remained, even in live code.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reported-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
We should not give domains access to something they don't necessarily
need by default. Remove it from the qemu driver docs too.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Add an option that lets the user specify the secret
that unlocks the server TLS key.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Turns out, that there are few bugs that are not that trivial to
fix (e.g. around block jobs). Instead of rushing in not
thoroughly tested fixes disable the feature temporarily for the
release.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
ACKed-by: Peter Krempa <pkrempa@redhat.com>
Turns out, there are couple of bugs that prevent this feature
from being operational. Given how close to the release we are
disable the feature temporarily. Hopefully, it can be enabled
back after all the bugs are fixed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
This config option allows users to set and enable lock manager
for domain metadata. The lock manager is going to be used by
security drivers to serialize each other when changing a file
ownership or changing the SELinux label. The only supported lock
manager is 'lockd' for now.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
QEMU uses /dev/sev device while creating the SEV guest, lets add /dev/sev
in the list of devices allowed to be accessed by the QEMU.
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The option is insecure and it has been long enough for users to migrate
their disk files to use explicit format. Drop the option and related
code.
The config parser still parses it and rejects statup if it's still
present in the config in enabled state.
The augeas lens is also kept so that users can disable it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend qemu_conf with user and group for running the tpm-emulator
and add directories to the configuration for the locations of the
log, state, and socket of the tpm-emulator.
Also add these new directories to the QEMU Makefile.inc.am and
the RPM spec file libvirt.spec.in.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just like we allow users overriding path to bridge-helper
detected at compile time we can allow them to override path to
qemu-pr-helper.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
This reverts commit 038eb472a0.
On reflection adding defaults for arbitrary guest XML device config
settings to the qemu.conf is not a sustainable path. Removing the
support for rx/tx queue size so that it doesn't set a bad precedent.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In 2074ef6cd4 and c56cdf259 (and friends) we've added two
attributes to virtio NICs: rx_queue_size and tx_queue_size.
However, sysadmins might want to set these on per-host basis but
don't necessarily have an access to domain XML (e.g. because they
are generated by some other app). So let's expose them under
qemu.conf (the settings from domain XML still take precedence as
they are more specific ones).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Add a new TLS X.509 certificate type - "vxhs". This will handle the
creation of a TLS certificate capability for properly configured
VxHS network block device clients.
The following describes the behavior of TLS for VxHS block device:
(1) Two new options have been added in /etc/libvirt/qemu.conf
to control TLS behavior with VxHS block devices
"vxhs_tls" and "vxhs_tls_x509_cert_dir".
(2) Setting "vxhs_tls=1" in /etc/libvirt/qemu.conf will enable
TLS for VxHS block devices.
(3) "vxhs_tls_x509_cert_dir" can be set to the full path where the
TLS CA certificate and the client certificate and keys are saved.
If this value is missing, the "default_tls_x509_cert_dir" will be
used instead. If the environment is not configured properly the
authentication to the VxHS server will fail.
Signed-off-by: Ashish Mittal <Ashish.Mittal@veritas.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
Add a path for UEFI VMs for AArch32 VMs, based on the path Debian is using.
libvirt is the de facto canonical location for defining where distros
should place these firmware images, so let's define this path here to try
and minimize distro fragmentation.
Add a new TLS X.509 certificate type - "migrate". This will handle the
creation of a TLS certificate capability (and possibly repository) to
be used for migrations. Similar to chardev's, credentials will be handled
via a libvirt secrets; however, unlike chardev's enablement and usage
will be via a CLI flag instead of a conf flag and a domain XML attribute.
The migrations using the *x509_verify flag require the client-cert.pem
and client-key.pem files to be present in the TLS directory - so let's
also be sure to note that in the qemu.conf file.
Signed-off-by: John Ferlan <jferlan@redhat.com>
So far, we are allowing /dev/vfio/vfio in the devices cgroup
unconditionally (and creating it in the namespace too). Even if
domain has no hostdev assignment configured. This is potential
security hole. Therefore, when starting the domain (or
hotplugging a hostdev) create & allow /dev/vfio/vfio too (if
needed).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Add new parameter memory_backing_dir where files will be stored when memoryBacking
source is selected as file.
Value is stored inside char* memoryBackingDir
Given how intrusive previous patches are, it might happen that
there's a bug or imperfection. Lets give users a way out: if they
set 'namespaces' to an empty array in qemu.conf the feature is
suppressed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
After a944bd92 we gained support for setting gluster debug level.
However, due to a space we haven't tested whether augeas file
actually works.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Add a new qemu.conf variables to store the UUID for the secret that could
be used to present credentials to access the TLS chardev. Since this will
be a server level and it's possible to use some sort of default, introduce
both the default and chardev logic at the same time making the setting of
the chardev check for it's own value, then if not present checking whether
the default value had been set.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Add a new TLS X.509 certificate type - "chardev". This will handle the
creation of a TLS certificate capability (and possibly repository) for
properly configured character device TCP backends.
Unlike the vnc and spice there is no "listen" or "passwd" associated. The
credentials eventually will be handled via a libvirt secret provided to
a specific backend.
Make use of the default verify option as well.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Rather than specify perhaps multiple TLS X.509 certificate directories,
let's create a "default" directory which can then be used if the service
(e.g. for now vnc and spice) does not supply a default directory.
Since the default for vnc and spice may have existed before without being
supplied, the default check will first check if the service specific path
exists and if so, set the cfg entry to that; otherwise, the default will
be set to the (now) new defaultTLSx509certdir.
Additionally add a "default_tls_x509_verify" entry which can also be used
to force the peer verification option (for vnc it's a x509verify option).
Add/alter the macro for the option being found in the config file to accept
the default value.
Signed-off-by: John Ferlan <jferlan@redhat.com>
We already have the ability to turn off dumping of guest
RAM via the domain XML. This is not particularly useful
though, as it is under control of the management application.
What is needed is a way for the sysadmin to turn off guest
RAM defaults globally, regardless of whether the mgmt app
provides its own way to set this in the domain XML.
So this adds a 'dump_guest_core' option in /etc/libvirt/qemu.conf
which defaults to false. ie guest RAM will never be included in
the QEMU core dumps by default. This default is different from
historical practice, but is considered to be more suitable as
a default because
a) guest RAM can be huge and so inflicts a DOS on the host
I/O subsystem when dumping core for QEMU crashes
b) guest RAM can contain alot of sensitive data belonging
to the VM owner. This should not generally be copied
around inside QEMU core dumps submitted to vendors for
debugging
c) guest RAM contents are rarely useful in diagnosing
QEMU crashes
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently the QEMU processes inherit their core dump rlimit
from libvirtd, which is really suboptimal. This change allows
their limit to be directly controlled from qemu.conf instead.
Currently the QEMU stdout/stderr streams are written directly to
a regular file (eg /var/log/libvirt/qemu/$GUEST.log). While those
can be rotated by logrotate (using copytruncate option) this is
not very efficient. It also leaves open a window of opportunity
for a compromised/broken QEMU to DOS the host filesystem by
writing lots of text to stdout/stderr.
This makes it possible to connect the stdout/stderr file handles
to a pipe that is provided by virtlogd. The virtlogd daemon will
read from this pipe and write data to the log file, performing
file rotation whenever a pre-determined size limit is reached.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Well, even though users can pass the list of UEFI:NVRAM pairs at the
configure time, we may maintain the list of widely available UEFI
ourselves too. And as arm64 begin to rises, OVMF was ported there too.
With a slight name change - it's called AAVMF, with AAVMF_CODE.fd
being the UEFI firmware and AAVMF_VARS.fd being the NVRAM store file.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
When enabling the migration_address option, by default it is
set to "127.0.0.1", but it's not a valid address for migration.
so we should add verification and set the default migration_address
to "0.0.0.0".
Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
When using split UEFI image, it may come handy if libvirt manages per
domain _VARS file automatically. While the _CODE file is RO and can be
shared among multiple domains, you certainly don't want to do that on
the _VARS file. This latter one needs to be per domain. So at the
domain startup process, if it's determined that domain needs _VARS
file it's copied from this master _VARS file. The location of the
master file is configurable in qemu.conf.
Temporary, on per domain basis the location of master NVRAM file can
be overridden by this @template attribute I'm inventing to the
<nvram/> element. All it does is holding path to the master NVRAM file
from which local copy is created. If that's the case, the map in
qemu.conf is not consulted.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
For now, we set the migration URI via command line '--migrate_uri' or
construct the URI by looking up the dest host's hostname which could be
solved by DNS automatically.
But in cases the dest host have two or more NICs to reach, we may need to
send the migration data over a specific NIC which is different from the
automatically resolved one for some reason like performance, security, etc.
Thus we must explicitly specify the migrateuri in command line everytime,
but it is too troublesome if there are many such hosts (and don't forget
virt-manager).
This patch adds a configuration file option on dest host to save the
default value set which can be specified to a migration hostname or
one of this host's addresses used for transferring data, thus user doesn't
have to specify it in command line everytime.
Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
