From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41113) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cQV1C-0001Xm-1u for qemu-devel@nongnu.org; Mon, 09 Jan 2017 03:09:28 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cQV18-0007vu-Os for qemu-devel@nongnu.org; Mon, 09 Jan 2017 03:09:26 -0500 Received: from mo69.mail-out.ovh.net ([178.32.228.69]:45034) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cQV18-0007tY-Eq for qemu-devel@nongnu.org; Mon, 09 Jan 2017 03:09:22 -0500 Received: from player696.ha.ovh.net (b7.ovh.net [213.186.33.57]) by mo69.mail-out.ovh.net (Postfix) with ESMTP id E879AE8B5 for ; Mon, 9 Jan 2017 09:09:20 +0100 (CET) Date: Mon, 9 Jan 2017 09:09:06 +0100 From: Greg Kurz Message-ID: <20170109090906.68302195@bahia.lan> In-Reply-To: References: <1483533149-12807-1-git-send-email-ashijeetacharya@gmail.com> <1483533149-12807-5-git-send-email-ashijeetacharya@gmail.com> <20170106174039.62523cdd@bahia.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2 4/4] migration: Fail migration blocker for --only-migratble List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Ashijeet Acharya 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" Again v3 turned into v2... what happened ? On Sun, 8 Jan 2017 12:55:51 +0530 Ashijeet Acharya wrote: > On Friday, January 6, 2017, Greg Kurz > wrote: > > > On Wed, 4 Jan 2017 18:02:29 +0530 > > Ashijeet Acharya wrote: > > > > > migrate_add_blocker should rightly fail if the '--only-migratable' > > > option was specified and the device in use should not be able to > > > perform the action which results in an unmigratable VM. > > > > > > Make migrate_add_blocker return -EACCES in this case. > > > > > > Signed-off-by: Ashijeet Acharya > > > --- > > > block/qcow.c | 5 ++++- > > > block/vdi.c | 5 ++++- > > > block/vhdx.c | 6 ++++-- > > > block/vmdk.c | 5 ++++- > > > block/vpc.c | 5 ++++- > > > block/vvfat.c | 6 ++++-- > > > hw/9pfs/9p.c | 8 +++++++- > > > hw/display/virtio-gpu.c | 9 +++++++-- > > > hw/intc/arm_gic_kvm.c | 5 ++++- > > > hw/intc/arm_gicv3_its_kvm.c | 5 ++++- > > > hw/intc/arm_gicv3_kvm.c | 5 ++++- > > > hw/misc/ivshmem.c | 10 ++++++++-- > > > hw/scsi/vhost-scsi.c | 8 +++++--- > > > hw/virtio/vhost.c | 6 ++++-- > > > migration/migration.c | 7 +++++++ > > > target-i386/kvm.c | 5 ++++- > > > 16 files changed, 78 insertions(+), 22 deletions(-) > > > > > > diff --git a/block/qcow.c b/block/qcow.c > > > index 11526a1..bdc6446 100644 > > > --- a/block/qcow.c > > > +++ b/block/qcow.c > > > @@ -254,7 +254,10 @@ static int qcow_open(BlockDriverState *bs, QDict > > *options, int flags, > > > bdrv_get_device_or_node_name(bs)); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use a node with qcow format > > as " > > > + "it does not support live migration"); > > > + } > > > goto fail; > > > } > > > > > > diff --git a/block/vdi.c b/block/vdi.c > > > index 2b56f52..0b011ea 100644 > > > --- a/block/vdi.c > > > +++ b/block/vdi.c > > > @@ -473,7 +473,10 @@ static int vdi_open(BlockDriverState *bs, QDict > > *options, int flags, > > > bdrv_get_device_or_node_name(bs)); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use a node with vdi format > > as " > > > + "it does not support live migration"); > > > + } > > > goto fail_free_bmap; > > > } > > > > > > diff --git a/block/vhdx.c b/block/vhdx.c > > > index d81941b..b8d53ec 100644 > > > --- a/block/vhdx.c > > > +++ b/block/vhdx.c > > > @@ -997,10 +997,12 @@ static int vhdx_open(BlockDriverState *bs, QDict > > *options, int flags, > > > bdrv_get_device_or_node_name(bs)); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use a node with vhdx format > > as " > > > + "it does not support live migration"); > > > + } > > > goto fail; > > > } > > > - > > > if (flags & BDRV_O_RDWR) { > > > ret = vhdx_update_headers(bs, s, false, NULL); > > > if (ret < 0) { > > > diff --git a/block/vmdk.c b/block/vmdk.c > > > index 4a45a83..defe400 100644 > > > --- a/block/vmdk.c > > > +++ b/block/vmdk.c > > > @@ -978,7 +978,10 @@ static int vmdk_open(BlockDriverState *bs, QDict > > *options, int flags, > > > bdrv_get_device_or_node_name(bs)); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use a node with vmdk format > > as " > > > + "it does not support live migration"); > > > + } > > > goto fail; > > > } > > > > > > diff --git a/block/vpc.c b/block/vpc.c > > > index 299a8c8..5e58d77 100644 > > > --- a/block/vpc.c > > > +++ b/block/vpc.c > > > @@ -428,7 +428,10 @@ static int vpc_open(BlockDriverState *bs, QDict > > *options, int flags, > > > bdrv_get_device_or_node_name(bs)); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use a node with vpc format > > as " > > > + "it does not support live migration"); > > > + } > > > goto fail; > > > } > > > > > > diff --git a/block/vvfat.c b/block/vvfat.c > > > index 3de3320..5a6e038 100644 > > > --- a/block/vvfat.c > > > +++ b/block/vvfat.c > > > @@ -1193,7 +1193,10 @@ static int vvfat_open(BlockDriverState *bs, QDict > > *options, int flags, > > > bdrv_get_device_or_node_name(bs)); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use a node with vvfat > > format " > > > + "as it does not support live > > migration"); > > > + } > > > goto fail; > > > } > > > } > > > @@ -1202,7 +1205,6 @@ static int vvfat_open(BlockDriverState *bs, QDict > > *options, int flags, > > > init_mbr(s, cyls, heads, secs); > > > } > > > > > > - // assert(is_consistent(s)); > > > qemu_co_mutex_init(&s->lock); > > > > > > ret = 0; > > > diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c > > > index 43cb065..3b4fd24 100644 > > > --- a/hw/9pfs/9p.c > > > +++ b/hw/9pfs/9p.c > > > @@ -1020,17 +1020,23 @@ static void coroutine_fn v9fs_attach(void > > *opaque) > > > */ > > > if (!s->migration_blocker) { > > > int ret; > > > + Error *local_err; > > > 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); > > > - ret = migrate_add_blocker(s->migration_blocker, NULL); > > > + ret = migrate_add_blocker(s->migration_blocker, &local_err); > > > if (ret < 0) { > > > + if (ret == -EACCES) { > > > + error_append_hint(&local_err, "Failed to mount VirtFS > > as it " > > > + "does not support live migration"); > > > + } > > > err = ret; > > > clunk_fid(s, fid); > > > error_free(s->migration_blocker); > > > s->migration_blocker = NULL; > > > goto out; > > > } > > > + error_free(local_err); > > > > Thinking again, I suggest you simply drop these changes: v9fs_attach() is > > triggered by the guest and doesn't cause QEMU to fail, so we don't really > > care. > > > > This might be naive but I didn't quite understand which changes you are > implying here. V2 to V3 or the entire diff in 9pfs? > The entire diff of 4/4 in 9pfs, which has no effect actually since local_err is not even passed to error_report_err() :) and anyway, this would allow a guest to fill the QEMU log with error messages if it deviced to call mount(2) repeatedly. > Ashijeet > > > Cheers. > > > > -- > > Greg > > > > > s->root_fid = fid; > > > } > > > > > > diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c > > > index 6e60b8c..fad95bf 100644 > > > --- a/hw/display/virtio-gpu.c > > > +++ b/hw/display/virtio-gpu.c > > > @@ -1102,6 +1102,7 @@ static void virtio_gpu_device_realize(DeviceState > > *qdev, Error **errp) > > > VirtIOGPU *g = VIRTIO_GPU(qdev); > > > bool have_virgl; > > > int i; > > > + int ret; > > > > > > if (g->conf.max_outputs > VIRTIO_GPU_MAX_SCANOUTS) { > > > error_setg(errp, "invalid max_outputs > %d", > > VIRTIO_GPU_MAX_SCANOUTS); > > > @@ -1120,8 +1121,12 @@ 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"); > > > - if (migrate_add_blocker(g->migration_blocker, errp) < 0) { > > > - error_free(g->migration_blocker); > > > + ret = migrate_add_blocker(g->migration_blocker, errp); > > > + if (ret < 0) { > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use virgl as it does > > not " > > > + "support live migration yet"); > > > + } > > > return; > > > } > > > } > > > diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c > > > index 3614daa..c2ef236 100644 > > > --- a/hw/intc/arm_gic_kvm.c > > > +++ b/hw/intc/arm_gic_kvm.c > > > @@ -515,7 +515,10 @@ static void kvm_arm_gic_realize(DeviceState *dev, > > Error **errp) > > > "not support vGICv2 > > migration"); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Failed to realize vGICv2 as > > its" > > > + " migrataion is not implemented yet"); > > > + } > > > return; > > > } > > > } > > > diff --git a/hw/intc/arm_gicv3_its_kvm.c b/hw/intc/arm_gicv3_its_kvm.c > > > index 950a02f..3474642 100644 > > > --- a/hw/intc/arm_gicv3_its_kvm.c > > > +++ b/hw/intc/arm_gicv3_its_kvm.c > > > @@ -70,7 +70,10 @@ static void kvm_arm_its_realize(DeviceState *dev, > > Error **errp) > > > error_setg(&s->migration_blocker, "vITS migration is not > > implemented"); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Failed to realize vITS as its > > migration " > > > + "is not implemented yet"); > > > + } > > > return; > > > } > > > > > > diff --git a/hw/intc/arm_gicv3_kvm.c b/hw/intc/arm_gicv3_kvm.c > > > index 06f6f30..be7b97c 100644 > > > --- a/hw/intc/arm_gicv3_kvm.c > > > +++ b/hw/intc/arm_gicv3_kvm.c > > > @@ -118,7 +118,10 @@ static void kvm_arm_gicv3_realize(DeviceState > > *dev, Error **errp) > > > error_setg(&s->migration_blocker, "vGICv3 migration is not > > implemented"); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - error_free(s->migration_blocker); > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Failed to realize vGICv3 as its > > migration" > > > + "is not implemented yet"); > > > + } > > > return; > > > } > > > > > > diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c > > > index 585cc5b..14ed60d 100644 > > > --- a/hw/misc/ivshmem.c > > > +++ b/hw/misc/ivshmem.c > > > @@ -837,6 +837,7 @@ static void ivshmem_common_realize(PCIDevice *dev, > > Error **errp) > > > { > > > IVShmemState *s = IVSHMEM_COMMON(dev); > > > Error *err = NULL; > > > + int ret; > > > uint8_t *pci_conf; > > > uint8_t attr = PCI_BASE_ADDRESS_SPACE_MEMORY | > > > PCI_BASE_ADDRESS_MEM_PREFETCH; > > > @@ -910,8 +911,13 @@ 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'"); > > > - if (migrate_add_blocker(s->migration_blocker, errp) < 0) { > > > - error_free(s->migration_blocker); > > > + ret = migrate_add_blocker(s->migration_blocker, errp); > > > + if (ret < 0) { > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use the 'peer mode' > > feature " > > > + "in device 'ivshmem' as it does not " > > > + "support live migration"); > > > + } > > > return; > > > } > > > } > > > diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c > > > index ff503d0..bb731b2 100644 > > > --- a/hw/scsi/vhost-scsi.c > > > +++ b/hw/scsi/vhost-scsi.c > > > @@ -245,7 +245,11 @@ static void vhost_scsi_realize(DeviceState *dev, > > Error **errp) > > > "vhost-scsi does not support migration"); > > > ret = migrate_add_blocker(s->migration_blocker, errp); > > > if (ret < 0) { > > > - goto free_blocker; > > > + if (ret == -EACCES) { > > > + error_append_hint(errp, "Cannot use vhost-scsi as it does > > not " > > > + "support live migration"); > > > + } > > > + goto close_fd; > > > } > > > > > > s->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; > > > @@ -272,8 +276,6 @@ static void vhost_scsi_realize(DeviceState *dev, > > Error **errp) > > > free_vqs: > > > migrate_del_blocker(s->migration_blocker); > > > g_free(s->dev.vqs); > > > - free_blocker: > > > - error_free(s->migration_blocker); > > > close_fd: > > > close(vhostfd); > > > return; > > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > > > index 416fada..6d2375a 100644 > > > --- a/hw/virtio/vhost.c > > > +++ b/hw/virtio/vhost.c > > > @@ -1160,8 +1160,10 @@ int vhost_dev_init(struct vhost_dev *hdev, void > > *opaque, > > > Error *local_err; > > > r = migrate_add_blocker(hdev->migration_blocker, &local_err); > > > if (r < 0) { > > > - error_report_err(local_err); > > > - error_free(hdev->migration_blocker); > > > + if (r == -EACCES) { > > > + error_append_hint(&local_err, "Cannot use vhost drivers > > as " > > > + "it does not support live migration"); > > > + } > > > goto fail_busyloop; > > > } > > > } > > > diff --git a/migration/migration.c b/migration/migration.c > > > index 713e012..ab34328 100644 > > > --- a/migration/migration.c > > > +++ b/migration/migration.c > > > @@ -1115,9 +1115,16 @@ int migrate_add_blocker(Error *reason, Error > > **errp) > > > { > > > if (migration_is_idle(NULL)) { > > > migration_blockers = g_slist_prepend(migration_blockers, > > reason); > > > + error_free(reason); > > > return 0; > > > } > > > > > > + if (only_migratable) { > > > + error_setg(errp, "Failed to add migration blocker: > > --only-migratable " > > > + "was specified"); > > > + return -EACCES; > > > + } > > > + > > > error_setg(errp, "Cannot block a migration already in-progress"); > > > return -EBUSY; > > > } > > > diff --git a/target-i386/kvm.c b/target-i386/kvm.c > > > index 6031a1c..f2c35d8 100644 > > > --- a/target-i386/kvm.c > > > +++ b/target-i386/kvm.c > > > @@ -963,6 +963,10 @@ int kvm_arch_init_vcpu(CPUState *cs) > > > " (invtsc flag)"); > > > r = migrate_add_blocker(invtsc_mig_blocker, NULL); > > > if (r < 0) { > > > + if (r == -EACCES) { > > > + error_report("kvm: non-migratable CPU device but" > > > + " --only-migratable was specified"); > > > + } > > > error_report("kvm: migrate_add_blocker failed"); > > > goto efail; > > > } > > > @@ -1009,7 +1013,6 @@ int kvm_arch_init_vcpu(CPUState *cs) > > > fail: > > > migrate_del_blocker(invtsc_mig_blocker); > > > efail: > > > - error_free(invtsc_mig_blocker); > > > return r; > > > } > > > > > > >