Commit Graph

8 Commits

Author SHA1 Message Date
Nico Boehr
38621181ae s390x/tod-kvm: don't save/restore the TOD in PV guests
Under PV, the guest's TOD clock is under control of the ultravisor and the
hypervisor cannot change it.

With upcoming kernel changes[1], the Linux kernel will reject QEMU's
request to adjust the guest's clock in this case, so don't attempt to set
the clock.

This avoids the following warning message on save/restore of a PV guest:

warning: Unable to set KVM guest TOD clock: Operation not supported

[1] https://lore.kernel.org/all/20221011160712.928239-2-nrb@linux.ibm.com/

Fixes: c3347ed0d2 ("s390x: protvirt: Support unpack facility")
Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Message-Id: <20221012123229.1196007-1-nrb@linux.ibm.com>
[thuth: Add curly braces]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2022-10-27 09:09:50 +02:00
Bernhard Beschow
5e78c98b7c Mark remaining global TypeInfo instances as const
More than 1k of TypeInfo instances are already marked as const. Mark the
remaining ones, too.

This commit was created with:
  git grep -z -l 'static TypeInfo' -- '*.c' | \
  xargs -0 sed -i 's/static TypeInfo/static const TypeInfo/'

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Message-id: 20220117145805.173070-2-shentey@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-02-21 13:30:20 +00:00
Cho, Yu-Chen
67043607d1 target/s390x: move kvm files into kvm/
move kvm files into kvm/
After the reshuffling, update MAINTAINERS accordingly.
Make use of the new directory:

target/s390x/kvm/

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Cho, Yu-Chen <acho@suse.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210707105324.23400-14-acho@suse.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2021-07-07 14:01:59 +02:00
Philippe Mathieu-Daudé
538f049704 sysemu: Let VMChangeStateHandler take boolean 'running' argument
The 'running' argument from VMChangeStateHandler does not require
other value than 0 / 1. Make it a plain boolean.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20210111152020.1422021-3-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-03-09 23:13:57 +01:00
Markus Armbruster
54d31236b9 sysemu: Split sysemu/runstate.h off sysemu/sysemu.h
sysemu/sysemu.h is a rather unfocused dumping ground for stuff related
to the system-emulator.  Evidence:

* It's included widely: in my "build everything" tree, changing
  sysemu/sysemu.h still triggers a recompile of some 1100 out of 6600
  objects (not counting tests and objects that don't depend on
  qemu/osdep.h, down from 5400 due to the previous two commits).

* It pulls in more than a dozen additional headers.

Split stuff related to run state management into its own header
sysemu/runstate.h.

Touching sysemu/sysemu.h now recompiles some 850 objects.  qemu/uuid.h
also drops from 1100 to 850, and qapi/qapi-types-run-state.h from 4400
to 4200.  Touching new sysemu/runstate.h recompiles some 500 objects.

Since I'm touching MAINTAINERS to add sysemu/runstate.h anyway, also
add qemu/main-loop.h.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-30-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[Unbreak OS-X build]
2019-08-16 13:37:36 +02:00
Markus Armbruster
0b8fa32f55 Include qemu/module.h where needed, drop it from qemu-common.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-4-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c
hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c;
ui/cocoa.m fixed up]
2019-06-12 13:18:33 +02:00
David Hildenbrand
9bc9d3d1ae s390x/tod: Properly stop the KVM TOD while the guest is not running
Just like on other architectures, we should stop the clock while the guest
is not running. This is already properly done for TCG. Right now, doing an
offline migration (stop, migrate, cont) can easily trigger stalls in the
guest.

Even doing a
    (hmp) stop
    ... wait 2 minutes ...
    (hmp) cont
will already trigger stalls.

So whenever the guest stops, backup the KVM TOD. When continuing to run
the guest, restore the KVM TOD.

One special case is starting a simple VM: Reading the TOD from KVM to
stop it right away until the guest is actually started means that the
time of any simple VM will already differ to the host time. We can
simply leave the TOD running and the guest won't be able to recognize
it.

For migration, we actually want to keep the TOD stopped until really
starting the guest. To be able to catch most errors, we should however
try to set the TOD in addition to simply storing it. So we can still
catch basic migration problems.

If anything goes wrong while backing up/restoring the TOD, we have to
ignore it (but print a warning). This is then basically a fallback to
old behavior (TOD remains running).

I tested this very basically with an initrd:
    1. Start a simple VM. Observed that the TOD is kept running. Old
       behavior.
    2. Ordinary live migration. Observed that the TOD is temporarily
       stopped on the destination when setting the new value and
       correctly started when finally starting the guest.
    3. Offline live migration. (stop, migrate, cont). Observed that the
       TOD will be stopped on the source with the "stop" command. On the
       destination, the TOD is temporarily stopped when setting the new
       value and correctly started when finally starting the guest via
       "cont".
    4. Simple stop/cont correctly stops/starts the TOD. (multiple stops
       or conts in a row have no effect, so works as expected)

In the future, we might want to send the guest a special kind of time sync
interrupt under some conditions, so it can synchronize its tod to the
host tod. This is interesting for migration scenarios but also when we
get time sync interrupts ourselves. This however will most probably have
to be handled in KVM (e.g. when the tods differ too much) and is not
desired e.g. when debugging the guest (single stepping should not
result in permanent time syncs). I consider something like that an add-on
on top of this basic "don't break the guest" handling.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181130094957.4121-1-david@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-12-12 10:39:28 +01:00
David Hildenbrand
8046f374a6 s390x/tod: factor out TOD into separate device
Let's treat this like a separate device. TCG will have to store the
actual state/time later on.

Include cpu-qom.h in kvm_s390x.h (due to S390CPU) to compile tod-kvm.c.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180627134410.4901-4-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-07-02 10:37:38 +02:00