Commit Graph

8 Commits

Author SHA1 Message Date
Michal Privoznik
88957116c9 qemu: Use memory-backend-* for regular guest memory
So far, Libvirt configures memory-backend-* for memory hotplug,
possibly NUMA nodes and in a few other cases. This patch
switches to constructing the memory-backend-* command line for
all cases. To keep ability to migrate guests a little hack is
used: the ID of the object is set to the one that QEMU uses
internally anyways. These IDs are stable (first started to appear
somewhere around v0.13.0-rc0~96) and can't change.

In fact, this patch does exactly what QEMU does internally. The
reason for moving the logic into Libvirt is that QEMU wants to
deprecate the old style of specifying memory.

So far, only x84_64 test cases are changed, because tests for
other architectures use older capabilities, which still lack the
QEMU_CAPS_MACHINE_MEMORY_BACKEND capability and they don't report
the RAM ID.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1836043

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2020-10-01 12:06:22 +02:00
Peter Krempa
3b8feb4793 qemu: capabilities: Replace aliased machine type by copy of the canonical machine
The previous approac of just purging the alias combined with the fact
that we filled in fake machine types in the test data meant that if a
test case used an alias machine type such as 'pc' or 'q35' it would not
properly resolve to the actual data returned by qemu.

This started to be a problem since the CPU driver now looks at the
default CPU reported with the machine type.

This patch replaces the original approach of just removing the alias by
replacing it with a copy of the machine type data which the type would
alias to. This means that we are using the real data while we don't
modify the test output after every qemu upgrade.

Additionally this change will allow us to drop adding the fake machine
types later.

The test fallout is from actually excercising the CPU driver with
actual data.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-27 14:55:03 +01:00
Michal Privoznik
e8c2c8bd07 qemu_command: Prefer '-overcommit mem-lock' over -realtime mlock'
The latter is deprecated and will be removed soon. The advised
replacement is '-overcommit mem-lock=on|off'.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-12 14:13:45 +02:00
Erik Skultety
75a9169881 qemu: command: Override HOME variable for system QEMU
By default, qemu user's home dir points to '/' which shouldn't be used
at all. We therefore pass the HOME variable from the current variable
iff not running as SUID, which means that for systemd we never set it.
This patch makes sure, that for system QEMU this is always set to
libDir/<driver>, session mode is left untouched.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-15 16:41:26 +01:00
Erik Skultety
7e73137495 qemu: command: Enforce setting XDG variables for system QEMU
For session mode, only XDG_CACHE_HOME is set, because we want to remain
integrating with services in user session, but for system mode, this
would have become reading/writing to '/' which carries the obvious issue
with permissions (also, '/' is the wrong location in 99.9% cases anyway).

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-15 16:41:26 +01:00
Peter Krempa
e546785dce tests: qemuxml2argv: Make tests based on DO_TEST_CAPS_LATEST stable
To avoid problems with test cases specifying an alias machine type which
would change once capabilities for a newer version are added strip all
alias machine types for the DO_TEST_CAPS_LATEST based tests.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-06-08 09:28:58 +02:00
Daniel P. Berrangé
30fb2276d8 qemu: support passing pre-opened UNIX socket listen FD
There is a race condition when spawning QEMU where libvirt has spawned
QEMU but the monitor socket is not yet open. Libvirt has to repeatedly
try to connect() to QEMU's monitor until eventually it succeeds, or
times out. We use kill() to check if QEMU is still alive so we avoid
waiting a long time if QEMU exited, but having a timeout at all is still
unpleasant.

With QEMU 2.12 we can pass in a pre-opened FD for UNIX domain or TCP
sockets. If libvirt has called bind() and listen() on this FD, then we
have a guarantee that libvirt can immediately call connect() and
succeed without any race.

Although we only really care about this for the monitor socket and agent
socket, this patch does FD passing for all UNIX socket based character
devices since there appears to be no downside to it.

We don't do FD passing for TCP sockets, however, because it is only
possible to pass a single FD, while some hostnames may require listening
on multiple FDs to cover IPv4 and IPv6 concurrently.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-06-05 17:30:28 +01:00
John Ferlan
87973a45f9 qemu: Add VM Generation ID to qemu command line
https://bugzilla.redhat.com/show_bug.cgi?id=1149445

If the domain requests usage of the genid functionality,
then add the QEMU '-device vmgenid' to the command line
providing either the supplied or generated GUID value.

Add tests for both a generated and supplied GUID value.

Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
2018-05-25 08:15:58 -04:00