From: Nico Boehr <n...@linux.ibm.com> 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-...@linux.ibm.com/ Fixes: c3347ed0d2ee ("s390x: protvirt: Support unpack facility") Signed-off-by: Nico Boehr <n...@linux.ibm.com> Message-Id: <20221012123229.1196007-1-...@linux.ibm.com> [thuth: Add curly braces] Signed-off-by: Thomas Huth <th...@redhat.com> --- hw/s390x/tod-kvm.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/hw/s390x/tod-kvm.c b/hw/s390x/tod-kvm.c index 9d0cbfbce2..e2202dae2d 100644 --- a/hw/s390x/tod-kvm.c +++ b/hw/s390x/tod-kvm.c @@ -13,6 +13,7 @@ #include "qemu/module.h" #include "sysemu/runstate.h" #include "hw/s390x/tod.h" +#include "hw/s390x/pv.h" #include "kvm/kvm_s390x.h" static void kvm_s390_get_tod_raw(S390TOD *tod, Error **errp) @@ -84,6 +85,14 @@ static void kvm_s390_tod_vm_state_change(void *opaque, bool running, S390TODState *td = opaque; Error *local_err = NULL; + /* + * Under PV, the clock is under ultravisor control, hence we cannot restore + * it on resume. + */ + if (s390_is_pv()) { + return; + } + if (running && td->stopped) { /* Set the old TOD when running the VM - start the TOD clock. */ kvm_s390_set_tod_raw(&td->base, &local_err); -- 2.31.1
