Looks like this patch broke migration from 2.10 to 2.9 (and older)
when ais is active.
2.9 says
error while loading state for instance 0x0 of device 's390-flic'
So we need to fence this for older machines types than 2.10.
This should also go in 2.10.1.
Will have a look.
On 07/14/2017 12:41 PM, Christian Borntraeger wrote:
> From: Yi Min Zhao <zyi...@linux.vnet.ibm.com>
>
> During migration we should transfer ais states to the target guest.
> This patch introduces a subsection to kvm_s390_flic_vmstate and new
> vmsd for qemu_flic. The ais states need to be migrated only when
> ais is supported.
>
> Signed-off-by: Yi Min Zhao <zyi...@linux.vnet.ibm.com>
> Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com>
> Reviewed-by: Cornelia Huck <coh...@redhat.com>
> ---
> hw/intc/s390_flic.c | 20 +++++++++++
> hw/intc/s390_flic_kvm.c | 81
> ++++++++++++++++++++++++++++++++++++++++++++
> include/hw/s390x/s390_flic.h | 1 +
> 3 files changed, 102 insertions(+)
>
> diff --git a/hw/intc/s390_flic.c b/hw/intc/s390_flic.c
> index 6e7c610..6eaf178 100644
> --- a/hw/intc/s390_flic.c
> +++ b/hw/intc/s390_flic.c
> @@ -134,12 +134,32 @@ static void qemu_s390_flic_reset(DeviceState *dev)
> flic->nimm = 0;
> }
>
> +bool ais_needed(void *opaque)
> +{
> + S390FLICState *s = opaque;
> +
> + return s->ais_supported;
> +}
> +
> +static const VMStateDescription qemu_s390_flic_vmstate = {
> + .name = "qemu-s390-flic",
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .needed = ais_needed,
> + .fields = (VMStateField[]) {
> + VMSTATE_UINT8(simm, QEMUS390FLICState),
> + VMSTATE_UINT8(nimm, QEMUS390FLICState),
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> static void qemu_s390_flic_class_init(ObjectClass *oc, void *data)
> {
> DeviceClass *dc = DEVICE_CLASS(oc);
> S390FLICStateClass *fsc = S390_FLIC_COMMON_CLASS(oc);
>
> dc->reset = qemu_s390_flic_reset;
> + dc->vmsd = &qemu_s390_flic_vmstate;
> fsc->register_io_adapter = qemu_s390_register_io_adapter;
> fsc->io_adapter_map = qemu_s390_io_adapter_map;
> fsc->add_adapter_routes = qemu_s390_add_adapter_routes;
> diff --git a/hw/intc/s390_flic_kvm.c b/hw/intc/s390_flic_kvm.c
> index d93503f..be3fd00 100644
> --- a/hw/intc/s390_flic_kvm.c
> +++ b/hw/intc/s390_flic_kvm.c
> @@ -413,7 +413,84 @@ out:
> return r;
> }
>
> +typedef struct KVMS390FLICStateMigTmp {
> + KVMS390FLICState *parent;
> + uint8_t simm;
> + uint8_t nimm;
> +} KVMS390FLICStateMigTmp;
> +
> +static void kvm_flic_ais_pre_save(void *opaque)
> +{
> + KVMS390FLICStateMigTmp *tmp = opaque;
> + KVMS390FLICState *flic = tmp->parent;
> + struct kvm_s390_ais_all ais;
> + struct kvm_device_attr attr = {
> + .group = KVM_DEV_FLIC_AISM_ALL,
> + .addr = (uint64_t)&ais,
> + .attr = sizeof(ais),
> + };
> +
> + if (ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr)) {
> + error_report("Failed to retrieve kvm flic ais states");
> + return;
> + }
> +
> + tmp->simm = ais.simm;
> + tmp->nimm = ais.nimm;
> +}
> +
> +static int kvm_flic_ais_post_load(void *opaque, int version_id)
> +{
> + KVMS390FLICStateMigTmp *tmp = opaque;
> + KVMS390FLICState *flic = tmp->parent;
> + struct kvm_s390_ais_all ais = {
> + .simm = tmp->simm,
> + .nimm = tmp->nimm,
> + };
> + struct kvm_device_attr attr = {
> + .group = KVM_DEV_FLIC_AISM_ALL,
> + .addr = (uint64_t)&ais,
> + };
> +
> + /* This can happen when the user mis-configures its guests in an
> + * incompatible fashion or without a CPU model. For example using
> + * qemu with -cpu host (which is not migration safe) and do a
> + * migration from a host that has AIS to a host that has no AIS.
> + * In that case the target system will reject the migration here.
> + */
> + if (!ais_needed(flic)) {
> + return -ENOSYS;
> + }
> +
> + return ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr) ? -errno : 0;
> +}
> +
> +static const VMStateDescription kvm_s390_flic_ais_tmp = {
> + .name = "s390-flic-ais-tmp",
> + .pre_save = kvm_flic_ais_pre_save,
> + .post_load = kvm_flic_ais_post_load,
> + .fields = (VMStateField[]) {
> + VMSTATE_UINT8(simm, KVMS390FLICStateMigTmp),
> + VMSTATE_UINT8(nimm, KVMS390FLICStateMigTmp),
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> +static const VMStateDescription kvm_s390_flic_vmstate_ais = {
> + .name = "s390-flic/ais",
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .needed = ais_needed,
> + .fields = (VMStateField[]) {
> + VMSTATE_WITH_TMP(KVMS390FLICState, KVMS390FLICStateMigTmp,
> + kvm_s390_flic_ais_tmp),
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> static const VMStateDescription kvm_s390_flic_vmstate = {
> + /* should have been like kvm-s390-flic,
> + * can't change without breaking compat */
> .name = "s390-flic",
> .version_id = FLIC_SAVEVM_VERSION,
> .minimum_version_id = FLIC_SAVEVM_VERSION,
> @@ -428,6 +505,10 @@ static const VMStateDescription kvm_s390_flic_vmstate = {
> .flags = VMS_SINGLE,
> },
> VMSTATE_END_OF_LIST()
> + },
> + .subsections = (const VMStateDescription * []) {
> + &kvm_s390_flic_vmstate_ais,
> + NULL
> }
> };
>
> diff --git a/include/hw/s390x/s390_flic.h b/include/hw/s390x/s390_flic.h
> index 2f173d9..7aab6ef 100644
> --- a/include/hw/s390x/s390_flic.h
> +++ b/include/hw/s390x/s390_flic.h
> @@ -89,6 +89,7 @@ typedef struct QEMUS390FLICState {
> void s390_flic_init(void);
>
> S390FLICState *s390_get_flic(void);
> +bool ais_needed(void *opaque);
>
> #ifdef CONFIG_KVM
> DeviceState *s390_flic_kvm_create(void);
>
