From: Jonathon Jongsma <jjongsma(a)redhat.com&gt; since qemu 6.0, if migration is blocked for some reason, 'query-migrate' will return an array of error strings describing the migration blockers. This can be used to check whether there are any devices blocking migration, etc. Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; Signed-off-by: Eugenio Pérez <eperezma(a)redhat.com&gt; --- v3: s/QEMU_MIGRATION_BLOCKED_REASONS/QEMU_CAPS_MIGRATION_BLOCKED_REASONS/ --- src/qemu/qemu_capabilities.c | 2 ++ src/qemu/qemu_capabilities.h | 1 + tests/qemucapabilitiesdata/caps_6.0.0.aarch64.xml | 1 + tests/qemucapabilitiesdata/caps_6.0.0.s390x.xml | 1 + tests/qemucapabilitiesdata/caps_6.0.0.x86_64.xml | 1 + tests/qemucapabilitiesdata/caps_6.1.0.x86_64.xml | 1 + tests/qemucapabilitiesdata/caps_6.2.0.aarch64.xml | 1 + tests/qemucapabilitiesdata/caps_6.2.0.ppc64.xml | 1 + tests/qemucapabilitiesdata/caps_6.2.0.x86_64.xml | 1 + tests/qemucapabilitiesdata/caps_7.0.0.aarch64.xml | 1 + tests/qemucapabilitiesdata/caps_7.0.0.ppc64.xml | 1 + tests/qemucapabilitiesdata/caps_7.0.0.x86_64.xml | 1 + tests/qemucapabilitiesdata/caps_7.1.0.x86_64.xml | 1 + 13 files changed, 14 insertions(+) diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 30b396d32d..b002fb98ed 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -672,6 +672,7 @@ VIR_ENUM_IMPL(virQEMUCaps, "display-dbus", /* QEMU_CAPS_DISPLAY_DBUS */ "iothread.thread-pool-max", /* QEMU_CAPS_IOTHREAD_THREAD_POOL_MAX */ "usb-host.guest-resets-all", /* QEMU_CAPS_USB_HOST_GUESTS_RESETS_ALL */ + "migration.blocked-reasons", /* QEMU_CAPS_MIGRATION_BLOCKED_REASONS */ ); @@ -1622,6 +1623,7 @@ static struct virQEMUCapsStringFlags virQEMUCapsQMPSchemaQueries[] = { { "chardev-add/arg-type/backend/+qemu-vdagent", QEMU_CAPS_CHARDEV_QEMU_VDAGENT }, { "query-display-options/ret-type/+dbus", QEMU_CAPS_DISPLAY_DBUS }, { "object-add/arg-type/+iothread/thread-pool-max", QEMU_CAPS_IOTHREAD_THREAD_POOL_MAX }, + { "query-migrate/ret-type/blocked-reasons", QEMU_CAPS_MIGRATION_BLOCKED_REASONS }, }; typedef struct _virQEMUCapsObjectTypeProps virQEMUCapsObjectTypeProps; diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h index d979a5ba3b..8f3090e2ce 100644 --- a/src/qemu/qemu_capabilities.h +++ b/src/qemu/qemu_capabilities.h @@ -651,6 +651,7 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */ QEMU_CAPS_DISPLAY_DBUS, /* -display dbus */ QEMU_CAPS_IOTHREAD_THREAD_POOL_MAX, /* -object iothread.thread-pool-max */ QEMU_CAPS_USB_HOST_GUESTS_RESETS_ALL, /* -device usb-host.guest-resets-all */ + QEMU_CAPS_MIGRATION_BLOCKED_REASONS, /* query-migrate returns 'blocked-reasons */ QEMU_CAPS_LAST /* this must always be the last item */ } virQEMUCapsFlags; diff --git a/tests/qemucapabilitiesdata/caps_6.0.0.aarch64.xml b/tests/qemucapabilitiesdata/caps_6.0.0.aarch64.xml index 01e30f4e02..4afd7b26ce 100644 --- a/tests/qemucapabilitiesdata/caps_6.0.0.aarch64.xml +++ b/tests/qemucapabilitiesdata/caps_6.0.0.aarch64.xml @@ -187,6 +187,7 @@ <flag name='virtio-iommu-pci'/> <flag name='virtio-net.rss'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>6000000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>61700242</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_6.0.0.s390x.xml b/tests/qemucapabilitiesdata/caps_6.0.0.s390x.xml index aa7b5deab5..c9cb85daa0 100644 --- a/tests/qemucapabilitiesdata/caps_6.0.0.s390x.xml +++ b/tests/qemucapabilitiesdata/caps_6.0.0.s390x.xml @@ -144,6 +144,7 @@ <flag name='memory-backend-file.prealloc-threads'/> <flag name='virtio-iommu-pci'/> <flag name='virtio-net.rss'/> + <flag name='migration.blocked-reasons'/> <version>6000000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>39100242</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_6.0.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_6.0.0.x86_64.xml index d9e385ab1d..508804521c 100644 --- a/tests/qemucapabilitiesdata/caps_6.0.0.x86_64.xml +++ b/tests/qemucapabilitiesdata/caps_6.0.0.x86_64.xml @@ -229,6 +229,7 @@ <flag name='virtio-iommu-pci'/> <flag name='virtio-net.rss'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>6000000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>43100242</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_6.1.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_6.1.0.x86_64.xml index 05f297dfa2..d4a540fafd 100644 --- a/tests/qemucapabilitiesdata/caps_6.1.0.x86_64.xml +++ b/tests/qemucapabilitiesdata/caps_6.1.0.x86_64.xml @@ -234,6 +234,7 @@ <flag name='virtio-net.rss'/> <flag name='chardev.qemu-vdagent'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>6001000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>43100243</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_6.2.0.aarch64.xml b/tests/qemucapabilitiesdata/caps_6.2.0.aarch64.xml index 9cb1a32354..71697fac95 100644 --- a/tests/qemucapabilitiesdata/caps_6.2.0.aarch64.xml +++ b/tests/qemucapabilitiesdata/caps_6.2.0.aarch64.xml @@ -199,6 +199,7 @@ <flag name='virtio-net.rss'/> <flag name='chardev.qemu-vdagent'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>6001050</version> <kvmVersion>0</kvmVersion> <microcodeVersion>61700244</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_6.2.0.ppc64.xml b/tests/qemucapabilitiesdata/caps_6.2.0.ppc64.xml index 5df148d787..3f86e03f18 100644 --- a/tests/qemucapabilitiesdata/caps_6.2.0.ppc64.xml +++ b/tests/qemucapabilitiesdata/caps_6.2.0.ppc64.xml @@ -193,6 +193,7 @@ <flag name='memory-backend-file.prealloc-threads'/> <flag name='virtio-iommu-pci'/> <flag name='virtio-net.rss'/> + <flag name='migration.blocked-reasons'/> <version>6002000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>42900244</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_6.2.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_6.2.0.x86_64.xml index dd011f8408..1a1a9643d4 100644 --- a/tests/qemucapabilitiesdata/caps_6.2.0.x86_64.xml +++ b/tests/qemucapabilitiesdata/caps_6.2.0.x86_64.xml @@ -236,6 +236,7 @@ <flag name='virtio-net.rss'/> <flag name='chardev.qemu-vdagent'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>6002000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>43100244</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_7.0.0.aarch64.xml b/tests/qemucapabilitiesdata/caps_7.0.0.aarch64.xml index 39a5cd154d..a3991e9853 100644 --- a/tests/qemucapabilitiesdata/caps_7.0.0.aarch64.xml +++ b/tests/qemucapabilitiesdata/caps_7.0.0.aarch64.xml @@ -207,6 +207,7 @@ <flag name='virtio-net.rss'/> <flag name='chardev.qemu-vdagent'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>6002092</version> <kvmVersion>0</kvmVersion> <microcodeVersion>61700243</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_7.0.0.ppc64.xml b/tests/qemucapabilitiesdata/caps_7.0.0.ppc64.xml index 6e872f4f85..67dff32f50 100644 --- a/tests/qemucapabilitiesdata/caps_7.0.0.ppc64.xml +++ b/tests/qemucapabilitiesdata/caps_7.0.0.ppc64.xml @@ -211,6 +211,7 @@ <flag name='virtio-net.rss'/> <flag name='chardev.qemu-vdagent'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>7000000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>42900243</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_7.0.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_7.0.0.x86_64.xml index a8f46df1cd..8ce423557e 100644 --- a/tests/qemucapabilitiesdata/caps_7.0.0.x86_64.xml +++ b/tests/qemucapabilitiesdata/caps_7.0.0.x86_64.xml @@ -241,6 +241,7 @@ <flag name='chardev.qemu-vdagent'/> <flag name='display-dbus'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>7000000</version> <kvmVersion>0</kvmVersion> <microcodeVersion>43100243</microcodeVersion> diff --git a/tests/qemucapabilitiesdata/caps_7.1.0.x86_64.xml b/tests/qemucapabilitiesdata/caps_7.1.0.x86_64.xml index 8464909698..2b2f1aef52 100644 --- a/tests/qemucapabilitiesdata/caps_7.1.0.x86_64.xml +++ b/tests/qemucapabilitiesdata/caps_7.1.0.x86_64.xml @@ -242,6 +242,7 @@ <flag name='display-dbus'/> <flag name='iothread.thread-pool-max'/> <flag name='usb-host.guest-resets-all'/> + <flag name='migration.blocked-reasons'/> <version>7000050</version> <kvmVersion>0</kvmVersion> <microcodeVersion>43100244</microcodeVersion> -- 2.31.1

since qemu 6.0, if migration is blocked for some reason, 'query-migrate' will return an array of error strings describing the migration blockers. This can be used to check whether there are any devices blocking migration, etc. Enable qemu monitor to send this query. This will allow qemuMigrationSrcIsAllowed to dynamically ask for migration blockers, reducing duplication. Signed-off-by: Eugenio Pérez <eperezma(a)redhat.com&gt; --- v3: * Squash some patches * Return ok in qemuMonitorJSONGetMigrationBlockers is there are no blockers. * Move note to function doc. --- src/qemu/qemu_monitor.c | 11 +++++++++ src/qemu/qemu_monitor.h | 4 ++++ src/qemu/qemu_monitor_json.c | 43 ++++++++++++++++++++++++++++++++++++ src/qemu/qemu_monitor_json.h | 3 +++ 4 files changed, 61 insertions(+) diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c index 109107eaae..e0939beecd 100644 --- a/src/qemu/qemu_monitor.c +++ b/src/qemu/qemu_monitor.c @@ -4486,3 +4486,14 @@ qemuMonitorMigrateRecover(qemuMonitor *mon, return qemuMonitorJSONMigrateRecover(mon, uri); } + +int +qemuMonitorGetMigrationBlockers(qemuMonitor *mon, + char ***blockers) +{ + VIR_DEBUG("blockers=%p", blockers); + + QEMU_CHECK_MONITOR(mon); + + return qemuMonitorJSONGetMigrationBlockers(mon, blockers); +} diff --git a/src/qemu/qemu_monitor.h b/src/qemu/qemu_monitor.h index cc1a0bc8c9..b82f198285 100644 --- a/src/qemu/qemu_monitor.h +++ b/src/qemu/qemu_monitor.h @@ -1543,3 +1543,7 @@ qemuMonitorChangeMemoryRequestedSize(qemuMonitor *mon, int qemuMonitorMigrateRecover(qemuMonitor *mon, const char *uri); + +int +qemuMonitorGetMigrationBlockers(qemuMonitor *mon, + char ***blockers); diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c index 5e4a86e5ad..6d15a458a3 100644 --- a/src/qemu/qemu_monitor_json.c +++ b/src/qemu/qemu_monitor_json.c @@ -3338,6 +3338,49 @@ int qemuMonitorJSONMigrate(qemuMonitor *mon, return 0; } +/* + * Get the exposed migration blockers. + * + * This function assume qemu has the capability of request them. + * + * It returns a NULL terminated array on blockers if there are any, or it set + * it to NULL otherwise. + */ +int qemuMonitorJSONGetMigrationBlockers(qemuMonitor *mon, + char ***blockers) +{ + g_autoptr(virJSONValue) cmd = NULL; + g_autoptr(virJSONValue) reply = NULL; + virJSONValue *data; + virJSONValue *jblockers; + size_t i; + + *blockers = NULL; + if (!(cmd = qemuMonitorJSONMakeCommand("query-migrate", NULL))) + return -1; + + if (qemuMonitorJSONCommand(mon, cmd, &reply) < 0) + return -1; + + if (qemuMonitorJSONCheckReply(cmd, reply, VIR_JSON_TYPE_OBJECT) < 0) + return -1; + + data = virJSONValueObjectGetObject(reply, "return"); + + if (!(jblockers = virJSONValueObjectGetArray(data, "blocked-reasons"))) + return 0; + + *blockers = g_new0(char *, virJSONValueArraySize(jblockers) + 1); + for (i = 0; i < virJSONValueArraySize(jblockers); i++) { + virJSONValue *jblocker = virJSONValueArrayGet(jblockers, i); + const char *blocker = virJSONValueGetString(jblocker); + + (*blockers)[i] = g_strdup(blocker); + } + + return 0; +} + int qemuMonitorJSONMigrateCancel(qemuMonitor *mon) { g_autoptr(virJSONValue) cmd = qemuMonitorJSONMakeCommand("migrate_cancel", NULL); diff --git a/src/qemu/qemu_monitor_json.h b/src/qemu/qemu_monitor_json.h index 2759566892..e4c65e250e 100644 --- a/src/qemu/qemu_monitor_json.h +++ b/src/qemu/qemu_monitor_json.h @@ -184,6 +184,9 @@ qemuMonitorJSONMigrate(qemuMonitor *mon, unsigned int flags, const char *uri); int +qemuMonitorJSONGetMigrationBlockers(qemuMonitor *mon, + char ***blockers); +int qemuMonitorJSONGetSpiceMigrationStatus(qemuMonitor *mon, bool *spice_migrated); -- 2.31.1

On Wed, Jul 20, 2022 at 3:58 PM Jiri Denemark <jdenemar(a)redhat.com&gt; wrote: I'll send a new version with this.

On Wed, Jul 20, 2022 at 14:15:57 +0200, Eugenio Pérez wrote: As mentioned in v2 review the virReportError call should be dropped as it overwrites the error reported by qemuDomainGetMigrationBlockers. That is, you can just if (qemuDomainGetMigrationBlockers(driver, vm, &blockers) < 0) return false; In the following patch you change ", " to "; ". I don't mind that much either way, but it should be done in this patch :-) Hmm, easy but not trivial changes so I guess v4 would be better. Jirka

On Wed, Jul 20, 2022 at 16:29:45 +0200, Eugenio Perez Martin wrote: Well in qemuDomainGetMigrationBlockers you now have if (!(jblockers = virJSONValueObjectGetArray(data, "blocked-reasons"))) return 0; so you would not get pass r != 0 in such case anyway. If you wanted to distinguish missing blocked-reasons (that is no blockers) and blocked-reasons which is not an array (invalid response), you would need to do something else: if (!(jblockers = virJSONValueObjectGet(data, "blocked-reasons"))) return 0; if (!virJSONValueIsArray(jblockers)) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("blocker-reasons is not an array")); return -1; } All this inside qemuDomainGetMigrationBlockers() to make sure the function reports an error when returning -1. The caller would not report any error anyway. Jirka

vDPA devices will be migratable soon. Since they are not migratable before qemu 6.0, and qemu pre-6.0 didn't have the capability of asking for migration blockers, let it hardcoded in that case. Otherwise, ask qemu about the explicit blocker. Signed-off-by: Eugenio Pérez <eperezma(a)redhat.com&gt; --- v3: Fix indentation --- src/qemu/qemu_migration.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c index 6ac4ef150b..45e16242f0 100644 --- a/src/qemu/qemu_migration.c +++ b/src/qemu/qemu_migration.c @@ -1454,9 +1454,11 @@ qemuMigrationSrcIsAllowed(virQEMUDriver *driver, int pauseReason; size_t i; int r; + bool blockedReasonsCap = virQEMUCapsGet(priv->qemuCaps, + QEMU_CAPS_MIGRATION_BLOCKED_REASONS); /* Ask qemu if it have a migration blocker */ - if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_BLOCKED_REASONS)) { + if (blockedReasonsCap) { g_auto(GStrv) blockers = NULL; r = qemuDomainGetMigrationBlockers(driver, vm, &blockers); if (r != 0) { @@ -1467,7 +1469,7 @@ qemuMigrationSrcIsAllowed(virQEMUDriver *driver, } if (blockers && blockers[0]) { - g_autofree char *reasons = g_strjoinv(", ", blockers); + g_autofree char *reasons = g_strjoinv("; ", blockers); virReportError(VIR_ERR_OPERATION_INVALID, _("cannot migrate domain: %s"), reasons); return false; @@ -1580,7 +1582,7 @@ qemuMigrationSrcIsAllowed(virQEMUDriver *driver, virDomainNetDef *net = vm->def->nets[i]; qemuSlirp *slirp; - if (net->type == VIR_DOMAIN_NET_TYPE_VDPA) { + if (!blockedReasonsCap && net->type == VIR_DOMAIN_NET_TYPE_VDPA) { virReportError(VIR_ERR_OPERATION_INVALID, "%s", _("vDPA devices cannot be migrated")); return false; -- 2.31.1

On Wed, Jul 20, 2022 at 4:02 PM Jiri Denemark <jdenemar(a)redhat.com&gt; wrote: Sorry, I squashed in the wrong patch, I'll send v4 with this. Thanks!