From: Greg Kurz <groug@kaod.org>
To: Ashijeet Acharya <ashijeetacharya@gmail.com>
Cc: dgilbert@redhat.com, jsnow@redhat.com, amit.shah@redhat.com,
pbonzini@redhat.com, kwolf@redhat.com, armbru@redhat.com,
quintela@redhat.com, mst@redhat.com, marcandre.lureau@redhat.com,
aneesh.kumar@linux.vnet.ibm.com, peter.maydell@linaro.org,
qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH v6 4/5] migration: disallow migrate_add_blocker during migration
Date: Fri, 20 Jan 2017 09:23:33 +0100 [thread overview]
Message-ID: <20170120092333.2fefd8d2@bahia.lan> (raw)
In-Reply-To: <1484566314-3987-5-git-send-email-ashijeetacharya@gmail.com>
On Mon, 16 Jan 2017 17:01:53 +0530
Ashijeet Acharya <ashijeetacharya@gmail.com> wrote:
> If a migration is already in progress and somebody attempts
> to add a migration blocker, this should rightly fail.
>
> Add an errp parameter and a retcode return value to migrate_add_blocker.
>
> Signed-off-by: John Snow <jsnow@redhat.com>
> Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
> ---
For the 9pfs part.
Acked-by: Greg Kurz <groug@kaod.org>
> block/qcow.c | 8 +++++++-
> block/vdi.c | 8 +++++++-
> block/vhdx.c | 17 +++++++++++------
> block/vmdk.c | 9 ++++++++-
> block/vpc.c | 11 ++++++++---
> block/vvfat.c | 19 ++++++++++++-------
> hw/9pfs/9p.c | 33 ++++++++++++++++++++++-----------
> hw/display/virtio-gpu.c | 32 +++++++++++++++++++-------------
> hw/intc/arm_gic_kvm.c | 17 +++++++++++------
> hw/intc/arm_gicv3_its_kvm.c | 20 +++++++++++++-------
> hw/intc/arm_gicv3_kvm.c | 19 ++++++++++++-------
> hw/misc/ivshmem.c | 14 ++++++++++----
> hw/scsi/vhost-scsi.c | 25 +++++++++++++++++++------
> hw/virtio/vhost.c | 8 +++++++-
> include/migration/migration.h | 7 ++++++-
> migration/migration.c | 37 +++++++++++++++++++++++++++++++++++--
> stubs/migr-blocker.c | 3 ++-
> target/i386/kvm.c | 16 +++++++++++++---
> 18 files changed, 222 insertions(+), 81 deletions(-)
>
> diff --git a/block/qcow.c b/block/qcow.c
> index 7540f43..fb738fc 100644
> --- a/block/qcow.c
> +++ b/block/qcow.c
> @@ -104,6 +104,7 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
> unsigned int len, i, shift;
> int ret;
> QCowHeader header;
> + Error *local_err = NULL;
>
> ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
> if (ret < 0) {
> @@ -252,7 +253,12 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
> error_setg(&s->migration_blocker, "The qcow format used by node '%s' "
> "does not support live migration",
> bdrv_get_device_or_node_name(bs));
> - migrate_add_blocker(s->migration_blocker);
> + ret = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + goto fail;
> + }
>
> qemu_co_mutex_init(&s->lock);
> return 0;
> diff --git a/block/vdi.c b/block/vdi.c
> index 96b78d5..0aeb940 100644
> --- a/block/vdi.c
> +++ b/block/vdi.c
> @@ -361,6 +361,7 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
> VdiHeader header;
> size_t bmap_size;
> int ret;
> + Error *local_err = NULL;
>
> logout("\n");
>
> @@ -471,7 +472,12 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
> error_setg(&s->migration_blocker, "The vdi format used by node '%s' "
> "does not support live migration",
> bdrv_get_device_or_node_name(bs));
> - migrate_add_blocker(s->migration_blocker);
> + ret = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + goto fail_free_bmap;
> + }
>
> qemu_co_mutex_init(&s->write_lock);
>
> diff --git a/block/vhdx.c b/block/vhdx.c
> index 0ba2f0a..68db9e0 100644
> --- a/block/vhdx.c
> +++ b/block/vhdx.c
> @@ -991,6 +991,17 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
> }
> }
>
> + /* Disable migration when VHDX images are used */
> + error_setg(&s->migration_blocker, "The vhdx format used by node '%s' "
> + "does not support live migration",
> + bdrv_get_device_or_node_name(bs));
> + ret = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + goto fail;
> + }
> +
> if (flags & BDRV_O_RDWR) {
> ret = vhdx_update_headers(bs, s, false, NULL);
> if (ret < 0) {
> @@ -1000,12 +1011,6 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
>
> /* TODO: differencing files */
>
> - /* Disable migration when VHDX images are used */
> - error_setg(&s->migration_blocker, "The vhdx format used by node '%s' "
> - "does not support live migration",
> - bdrv_get_device_or_node_name(bs));
> - migrate_add_blocker(s->migration_blocker);
> -
> return 0;
> fail:
> vhdx_close(bs);
> diff --git a/block/vmdk.c b/block/vmdk.c
> index a11c27a..7750212 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -941,6 +941,7 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
> int ret;
> BDRVVmdkState *s = bs->opaque;
> uint32_t magic;
> + Error *local_err = NULL;
>
> buf = vmdk_read_desc(bs->file, 0, errp);
> if (!buf) {
> @@ -976,7 +977,13 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
> error_setg(&s->migration_blocker, "The vmdk format used by node '%s' "
> "does not support live migration",
> bdrv_get_device_or_node_name(bs));
> - migrate_add_blocker(s->migration_blocker);
> + ret = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + goto fail;
> + }
> +
> g_free(buf);
> return 0;
>
> diff --git a/block/vpc.c b/block/vpc.c
> index 8d5886f..ed6353d 100644
> --- a/block/vpc.c
> +++ b/block/vpc.c
> @@ -422,13 +422,18 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
> #endif
> }
>
> - qemu_co_mutex_init(&s->lock);
> -
> /* Disable migration when VHD images are used */
> error_setg(&s->migration_blocker, "The vpc format used by node '%s' "
> "does not support live migration",
> bdrv_get_device_or_node_name(bs));
> - migrate_add_blocker(s->migration_blocker);
> + ret = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + goto fail;
> + }
> +
> + qemu_co_mutex_init(&s->lock);
>
> return 0;
>
> diff --git a/block/vvfat.c b/block/vvfat.c
> index 7b706dc..c6bf67e 100644
> --- a/block/vvfat.c
> +++ b/block/vvfat.c
> @@ -1185,21 +1185,26 @@ static int vvfat_open(BlockDriverState *bs, QDict *options, int flags,
>
> s->sector_count = s->faked_sectors + s->sectors_per_cluster*s->cluster_count;
>
> - if (s->first_sectors_number == 0x40) {
> - init_mbr(s, cyls, heads, secs);
> - }
> -
> - qemu_co_mutex_init(&s->lock);
> -
> /* Disable migration when vvfat is used rw */
> if (s->qcow) {
> error_setg(&s->migration_blocker,
> "The vvfat (rw) format used by node '%s' "
> "does not support live migration",
> bdrv_get_device_or_node_name(bs));
> - migrate_add_blocker(s->migration_blocker);
> + ret = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + goto fail;
> + }
> }
>
> + if (s->first_sectors_number == 0x40) {
> + init_mbr(s, cyls, heads, secs);
> + }
> +
> + qemu_co_mutex_init(&s->lock);
> +
> ret = 0;
> fail:
> qemu_opts_del(opts);
> diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
> index fa58877..06b6e7e 100644
> --- a/hw/9pfs/9p.c
> +++ b/hw/9pfs/9p.c
> @@ -979,6 +979,7 @@ static void coroutine_fn v9fs_attach(void *opaque)
> size_t offset = 7;
> V9fsQID qid;
> ssize_t err;
> + Error *local_err = NULL;
>
> v9fs_string_init(&uname);
> v9fs_string_init(&aname);
> @@ -1007,26 +1008,36 @@ static void coroutine_fn v9fs_attach(void *opaque)
> clunk_fid(s, fid);
> goto out;
> }
> - err = pdu_marshal(pdu, offset, "Q", &qid);
> - if (err < 0) {
> - clunk_fid(s, fid);
> - goto out;
> - }
> - err += offset;
> - memcpy(&s->root_qid, &qid, sizeof(qid));
> - trace_v9fs_attach_return(pdu->tag, pdu->id,
> - qid.type, qid.version, qid.path);
> +
> /*
> * disable migration if we haven't done already.
> * attach could get called multiple times for the same export.
> */
> if (!s->migration_blocker) {
> - s->root_fid = fid;
> error_setg(&s->migration_blocker,
> "Migration is disabled when VirtFS export path '%s' is mounted in the guest using mount_tag '%s'",
> s->ctx.fs_root ? s->ctx.fs_root : "NULL", s->tag);
> - migrate_add_blocker(s->migration_blocker);
> + err = migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_free(local_err);
> + error_free(s->migration_blocker);
> + s->migration_blocker = NULL;
> + clunk_fid(s, fid);
> + goto out;
> + }
> + s->root_fid = fid;
> + }
> +
> + err = pdu_marshal(pdu, offset, "Q", &qid);
> + if (err < 0) {
> + clunk_fid(s, fid);
> + goto out;
> }
> + err += offset;
> +
> + memcpy(&s->root_qid, &qid, sizeof(qid));
> + trace_v9fs_attach_return(pdu->tag, pdu->id,
> + qid.type, qid.version, qid.path);
> out:
> put_fid(pdu, fidp);
> out_nofid:
> diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
> index 7a15c61..d8e3d1c 100644
> --- a/hw/display/virtio-gpu.c
> +++ b/hw/display/virtio-gpu.c
> @@ -1132,6 +1132,7 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
> VirtIODevice *vdev = VIRTIO_DEVICE(qdev);
> VirtIOGPU *g = VIRTIO_GPU(qdev);
> bool have_virgl;
> + Error *local_err = NULL;
> int i;
>
> if (g->conf.max_outputs > VIRTIO_GPU_MAX_SCANOUTS) {
> @@ -1139,14 +1140,6 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
> return;
> }
>
> - g->config_size = sizeof(struct virtio_gpu_config);
> - g->virtio_config.num_scanouts = g->conf.max_outputs;
> - virtio_init(VIRTIO_DEVICE(g), "virtio-gpu", VIRTIO_ID_GPU,
> - g->config_size);
> -
> - g->req_state[0].width = 1024;
> - g->req_state[0].height = 768;
> -
> g->use_virgl_renderer = false;
> #if !defined(CONFIG_VIRGL) || defined(HOST_WORDS_BIGENDIAN)
> have_virgl = false;
> @@ -1158,6 +1151,24 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
> }
>
> if (virtio_gpu_virgl_enabled(g->conf)) {
> + error_setg(&g->migration_blocker, "virgl is not yet migratable");
> + migrate_add_blocker(g->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(g->migration_blocker);
> + return;
> + }
> + }
> +
> + g->config_size = sizeof(struct virtio_gpu_config);
> + g->virtio_config.num_scanouts = g->conf.max_outputs;
> + virtio_init(VIRTIO_DEVICE(g), "virtio-gpu", VIRTIO_ID_GPU,
> + g->config_size);
> +
> + g->req_state[0].width = 1024;
> + g->req_state[0].height = 768;
> +
> + if (virtio_gpu_virgl_enabled(g->conf)) {
> /* use larger control queue in 3d mode */
> g->ctrl_vq = virtio_add_queue(vdev, 256, virtio_gpu_handle_ctrl_cb);
> g->cursor_vq = virtio_add_queue(vdev, 16, virtio_gpu_handle_cursor_cb);
> @@ -1183,11 +1194,6 @@ static void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
> dpy_gfx_replace_surface(g->scanout[i].con, NULL);
> }
> }
> -
> - if (virtio_gpu_virgl_enabled(g->conf)) {
> - error_setg(&g->migration_blocker, "virgl is not yet migratable");
> - migrate_add_blocker(g->migration_blocker);
> - }
> }
>
> static void virtio_gpu_device_unrealize(DeviceState *qdev, Error **errp)
> diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c
> index 11729ee..ec952ec 100644
> --- a/hw/intc/arm_gic_kvm.c
> +++ b/hw/intc/arm_gic_kvm.c
> @@ -510,6 +510,17 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
> return;
> }
>
> + if (!kvm_arm_gic_can_save_restore(s)) {
> + error_setg(&s->migration_blocker, "This operating system kernel does "
> + "not support vGICv2 migration");
> + migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + return;
> + }
> + }
> +
> gic_init_irqs_and_mmio(s, kvm_arm_gicv2_set_irq, NULL);
>
> for (i = 0; i < s->num_irq - GIC_INTERNAL; i++) {
> @@ -558,12 +569,6 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
> KVM_VGIC_V2_ADDR_TYPE_CPU,
> s->dev_fd);
>
> - if (!kvm_arm_gic_can_save_restore(s)) {
> - error_setg(&s->migration_blocker, "This operating system kernel does "
> - "not support vGICv2 migration");
> - migrate_add_blocker(s->migration_blocker);
> - }
> -
> if (kvm_has_gsi_routing()) {
> /* set up irq routing */
> kvm_init_irq_routing(kvm_state);
> diff --git a/hw/intc/arm_gicv3_its_kvm.c b/hw/intc/arm_gicv3_its_kvm.c
> index fc246e0..bd4f3aa 100644
> --- a/hw/intc/arm_gicv3_its_kvm.c
> +++ b/hw/intc/arm_gicv3_its_kvm.c
> @@ -56,6 +56,19 @@ static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid)
> static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
> {
> GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
> + Error *local_err = NULL;
> +
> + /*
> + * Block migration of a KVM GICv3 ITS device: the API for saving and
> + * restoring the state in the kernel is not yet available
> + */
> + error_setg(&s->migration_blocker, "vITS migration is not implemented");
> + migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + return;
> + }
>
> s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_ITS, false);
> if (s->dev_fd < 0) {
> @@ -73,13 +86,6 @@ static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
>
> gicv3_its_init_mmio(s, NULL);
>
> - /*
> - * Block migration of a KVM GICv3 ITS device: the API for saving and
> - * restoring the state in the kernel is not yet available
> - */
> - error_setg(&s->migration_blocker, "vITS migration is not implemented");
> - migrate_add_blocker(s->migration_blocker);
> -
> kvm_msi_use_devid = true;
> kvm_gsi_direct_mapping = false;
> kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();
> diff --git a/hw/intc/arm_gicv3_kvm.c b/hw/intc/arm_gicv3_kvm.c
> index 199a439..d69dc47 100644
> --- a/hw/intc/arm_gicv3_kvm.c
> +++ b/hw/intc/arm_gicv3_kvm.c
> @@ -103,6 +103,18 @@ static void kvm_arm_gicv3_realize(DeviceState *dev, Error **errp)
>
> gicv3_init_irqs_and_mmio(s, kvm_arm_gicv3_set_irq, NULL);
>
> + /* Block migration of a KVM GICv3 device: the API for saving and restoring
> + * the state in the kernel is not yet finalised in the kernel or
> + * implemented in QEMU.
> + */
> + error_setg(&s->migration_blocker, "vGICv3 migration is not implemented");
> + migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + return;
> + }
> +
> /* Try to create the device via the device control API */
> s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_V3, false);
> if (s->dev_fd < 0) {
> @@ -122,13 +134,6 @@ static void kvm_arm_gicv3_realize(DeviceState *dev, Error **errp)
> kvm_arm_register_device(&s->iomem_redist, -1, KVM_DEV_ARM_VGIC_GRP_ADDR,
> KVM_VGIC_V3_ADDR_TYPE_REDIST, s->dev_fd);
>
> - /* Block migration of a KVM GICv3 device: the API for saving and restoring
> - * the state in the kernel is not yet finalised in the kernel or
> - * implemented in QEMU.
> - */
> - error_setg(&s->migration_blocker, "vGICv3 migration is not implemented");
> - migrate_add_blocker(s->migration_blocker);
> -
> if (kvm_has_gsi_routing()) {
> /* set up irq routing */
> kvm_init_irq_routing(kvm_state);
> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
> index abeaf3d..fd14d7a 100644
> --- a/hw/misc/ivshmem.c
> +++ b/hw/misc/ivshmem.c
> @@ -840,6 +840,7 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
> uint8_t *pci_conf;
> uint8_t attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
> PCI_BASE_ADDRESS_MEM_PREFETCH;
> + Error *local_err = NULL;
>
> /* IRQFD requires MSI */
> if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
> @@ -903,9 +904,6 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
> }
> }
>
> - vmstate_register_ram(s->ivshmem_bar2, DEVICE(s));
> - pci_register_bar(PCI_DEVICE(s), 2, attr, s->ivshmem_bar2);
> -
> if (s->master == ON_OFF_AUTO_AUTO) {
> s->master = s->vm_id == 0 ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
> }
> @@ -913,8 +911,16 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
> if (!ivshmem_is_master(s)) {
> error_setg(&s->migration_blocker,
> "Migration is disabled when using feature 'peer mode' in device 'ivshmem'");
> - migrate_add_blocker(s->migration_blocker);
> + migrate_add_blocker(s->migration_blocker, &local_err);
> + if (local_err) {
> + error_propagate(errp, local_err);
> + error_free(s->migration_blocker);
> + return;
> + }
> }
> +
> + vmstate_register_ram(s->ivshmem_bar2, DEVICE(s));
> + pci_register_bar(PCI_DEVICE(s), 2, attr, s->ivshmem_bar2);
> }
>
> static void ivshmem_exit(PCIDevice *dev)
> diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
> index 5b26946..c491ece 100644
> --- a/hw/scsi/vhost-scsi.c
> +++ b/hw/scsi/vhost-scsi.c
> @@ -238,8 +238,16 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
> vhost_dummy_handle_output);
> if (err != NULL) {
> error_propagate(errp, err);
> - close(vhostfd);
> - return;
> + goto close_fd;
> + }
> +
> + error_setg(&s->migration_blocker,
> + "vhost-scsi does not support migration");
> + migrate_add_blocker(s->migration_blocker, &err);
> + if (err) {
> + error_propagate(errp, err);
> + error_free(s->migration_blocker);
> + goto close_fd;
> }
>
> s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
> @@ -252,7 +260,7 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
> if (ret < 0) {
> error_setg(errp, "vhost-scsi: vhost initialization failed: %s",
> strerror(-ret));
> - return;
> + goto free_vqs;
> }
>
> /* At present, channel and lun both are 0 for bootable vhost-scsi disk */
> @@ -261,9 +269,14 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
> /* Note: we can also get the minimum tpgt from kernel */
> s->target = vs->conf.boot_tpgt;
>
> - error_setg(&s->migration_blocker,
> - "vhost-scsi does not support migration");
> - migrate_add_blocker(s->migration_blocker);
> + return;
> +
> + free_vqs:
> + migrate_del_blocker(s->migration_blocker);
> + g_free(s->dev.vqs);
> + close_fd:
> + close(vhostfd);
> + return;
> }
>
> static void vhost_scsi_unrealize(DeviceState *dev, Error **errp)
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index d396b22..cca1788 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1082,6 +1082,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
> {
> uint64_t features;
> int i, r, n_initialized_vqs = 0;
> + Error *local_err = NULL;
>
> hdev->migration_blocker = NULL;
>
> @@ -1158,7 +1159,12 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque,
> }
>
> if (hdev->migration_blocker != NULL) {
> - migrate_add_blocker(hdev->migration_blocker);
> + r = migrate_add_blocker(hdev->migration_blocker, &local_err);
> + if (local_err) {
> + error_report_err(local_err);
> + error_free(hdev->migration_blocker);
> + goto fail_busyloop;
> + }
> }
>
> hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions));
> diff --git a/include/migration/migration.h b/include/migration/migration.h
> index 40b3697..bcbdb03 100644
> --- a/include/migration/migration.h
> +++ b/include/migration/migration.h
> @@ -243,6 +243,7 @@ void remove_migration_state_change_notifier(Notifier *notify);
> MigrationState *migrate_init(const MigrationParams *params);
> bool migration_is_blocked(Error **errp);
> bool migration_in_setup(MigrationState *);
> +bool migration_is_idle(MigrationState *s);
> bool migration_has_finished(MigrationState *);
> bool migration_has_failed(MigrationState *);
> /* True if outgoing migration has entered postcopy phase */
> @@ -287,8 +288,12 @@ int ram_postcopy_incoming_init(MigrationIncomingState *mis);
> * @migrate_add_blocker - prevent migration from proceeding
> *
> * @reason - an error to be returned whenever migration is attempted
> + *
> + * @errp - [out] The reason (if any) we cannot block migration right now.
> + *
> + * @returns - 0 on success, -EBUSY on failure, with errp set.
> */
> -void migrate_add_blocker(Error *reason);
> +int migrate_add_blocker(Error *reason, Error **errp);
>
> /**
> * @migrate_del_blocker - remove a blocking error from migration
> diff --git a/migration/migration.c b/migration/migration.c
> index f498ab8..0d88286 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -1044,6 +1044,31 @@ bool migration_in_postcopy_after_devices(MigrationState *s)
> return migration_in_postcopy(s) && s->postcopy_after_devices;
> }
>
> +bool migration_is_idle(MigrationState *s)
> +{
> + if (!s) {
> + s = migrate_get_current();
> + }
> +
> + switch (s->state) {
> + case MIGRATION_STATUS_NONE:
> + case MIGRATION_STATUS_CANCELLED:
> + case MIGRATION_STATUS_COMPLETED:
> + case MIGRATION_STATUS_FAILED:
> + return true;
> + case MIGRATION_STATUS_SETUP:
> + case MIGRATION_STATUS_CANCELLING:
> + case MIGRATION_STATUS_ACTIVE:
> + case MIGRATION_STATUS_POSTCOPY_ACTIVE:
> + case MIGRATION_STATUS_COLO:
> + return false;
> + case MIGRATION_STATUS__MAX:
> + g_assert_not_reached();
> + }
> +
> + return false;
> +}
> +
> MigrationState *migrate_init(const MigrationParams *params)
> {
> MigrationState *s = migrate_get_current();
> @@ -1086,9 +1111,17 @@ MigrationState *migrate_init(const MigrationParams *params)
>
> static GSList *migration_blockers;
>
> -void migrate_add_blocker(Error *reason)
> +int migrate_add_blocker(Error *reason, Error **errp)
> {
> - migration_blockers = g_slist_prepend(migration_blockers, reason);
> + if (migration_is_idle(NULL)) {
> + migration_blockers = g_slist_prepend(migration_blockers, reason);
> + return 0;
> + }
> +
> + error_propagate(errp, error_copy(reason));
> + error_prepend(errp, "disallowing migration blocker (migration in "
> + "progress) for: ");
> + return -EBUSY;
> }
>
> void migrate_del_blocker(Error *reason)
> diff --git a/stubs/migr-blocker.c b/stubs/migr-blocker.c
> index 8ab3604..a5ba18f 100644
> --- a/stubs/migr-blocker.c
> +++ b/stubs/migr-blocker.c
> @@ -2,8 +2,9 @@
> #include "qemu-common.h"
> #include "migration/migration.h"
>
> -void migrate_add_blocker(Error *reason)
> +int migrate_add_blocker(Error *reason, Error **errp)
> {
> + return 0;
> }
>
> void migrate_del_blocker(Error *reason)
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index 10a9cd8..9887052 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -709,6 +709,7 @@ int kvm_arch_init_vcpu(CPUState *cs)
> uint32_t signature[3];
> int kvm_base = KVM_CPUID_SIGNATURE;
> int r;
> + Error *local_err = NULL;
>
> memset(&cpuid_data, 0, sizeof(cpuid_data));
>
> @@ -968,7 +969,12 @@ int kvm_arch_init_vcpu(CPUState *cs)
> error_setg(&invtsc_mig_blocker,
> "State blocked by non-migratable CPU device"
> " (invtsc flag)");
> - migrate_add_blocker(invtsc_mig_blocker);
> + r = migrate_add_blocker(invtsc_mig_blocker, &local_err);
> + if (local_err) {
> + error_report_err(local_err);
> + error_free(invtsc_mig_blocker);
> + goto fail;
> + }
> /* for savevm */
> vmstate_x86_cpu.unmigratable = 1;
> }
> @@ -976,12 +982,12 @@ int kvm_arch_init_vcpu(CPUState *cs)
> cpuid_data.cpuid.padding = 0;
> r = kvm_vcpu_ioctl(cs, KVM_SET_CPUID2, &cpuid_data);
> if (r) {
> - return r;
> + goto fail;
> }
>
> r = kvm_arch_set_tsc_khz(cs);
> if (r < 0) {
> - return r;
> + goto fail;
> }
>
> /* vcpu's TSC frequency is either specified by user, or following
> @@ -1008,6 +1014,10 @@ int kvm_arch_init_vcpu(CPUState *cs)
> }
>
> return 0;
> +
> + fail:
> + migrate_del_blocker(invtsc_mig_blocker);
> + return r;
> }
>
> void kvm_arch_reset_vcpu(X86CPU *cpu)
next prev parent reply other threads:[~2017-01-20 8:24 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-16 11:31 [Qemu-devel] [PATCH v6 0/5] Introduce a new --only-migratable option Ashijeet Acharya
2017-01-16 11:31 ` [Qemu-devel] [PATCH v6 1/5] block/vvfat: Remove the undesirable comment Ashijeet Acharya
2017-01-19 17:49 ` Dr. David Alan Gilbert
2017-01-16 11:31 ` [Qemu-devel] [PATCH v6 2/5] migration: Add a new option to enable only-migratable Ashijeet Acharya
2017-01-19 18:02 ` Dr. David Alan Gilbert
2017-01-24 8:36 ` Juan Quintela
2017-01-16 11:31 ` [Qemu-devel] [PATCH v6 3/5] migration: Allow "device add" options to only add migratable devices Ashijeet Acharya
2017-01-19 18:52 ` Dr. David Alan Gilbert
2017-01-16 11:31 ` [Qemu-devel] [PATCH v6 4/5] migration: disallow migrate_add_blocker during migration Ashijeet Acharya
2017-01-19 19:40 ` Dr. David Alan Gilbert
2017-01-20 8:23 ` Greg Kurz [this message]
2017-01-16 11:31 ` [Qemu-devel] [PATCH v6 5/5] migration: Fail migration blocker for --only-migratable Ashijeet Acharya
2017-01-19 19:41 ` Dr. David Alan Gilbert
2017-01-24 8:37 ` Juan Quintela
2017-01-24 11:51 ` [Qemu-devel] [PATCH v6 0/5] Introduce a new --only-migratable option Dr. David Alan Gilbert
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170120092333.2fefd8d2@bahia.lan \
--to=groug@kaod.org \
--cc=amit.shah@redhat.com \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=armbru@redhat.com \
--cc=ashijeetacharya@gmail.com \
--cc=dgilbert@redhat.com \
--cc=jsnow@redhat.com \
--cc=kwolf@redhat.com \
--cc=marcandre.lureau@redhat.com \
--cc=mst@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
--cc=quintela@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.