[libvirt] [PATCH] qemu: Always format CPU topology

[Jiri Denemark]

When libvirt cannot find a suitable CPU model for host CPU (easily
reproducible by running libvirt in a guest), it would not provide CPU
topology in capabilities XML either. Even though CPU topology is known
and can be queried by virNodeGetInfo. With this patch, CPU topology will
always be provided in capabilities XML regardless on the presence of CPU
model.
---
 src/qemu/qemu_capabilities.c | 6 +++---
 src/qemu/qemu_command.c      | 1 +
 src/qemu/qemu_domain.c       | 4 +++-
 src/qemu/qemu_driver.c       | 3 ++-
 4 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 985d4de..7c391b3 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -685,6 +685,7 @@ qemuCapsInitGuest(virCapsPtr caps,
     nmachines = 0;
 
     if (caps->host.cpu &&
+        caps->host.cpu->model &&
         qemuCapsGetCPUDefinitions(qemubinCaps, NULL) > 0 &&
         !virCapabilitiesAddGuestFeature(guest, "cpuselection", 1, 0))
         goto error;
@@ -781,12 +782,11 @@ qemuCapsInitCPU(virCapsPtr caps,
     cpu->sockets = nodeinfo.sockets;
     cpu->cores = nodeinfo.cores;
     cpu->threads = nodeinfo.threads;
+    caps->host.cpu = cpu;
 
     if (!(data = cpuNodeData(arch))
         || cpuDecode(cpu, data, NULL, 0, NULL) < 0)
-        goto error;
-
-    caps->host.cpu = cpu;
+        goto cleanup;
 
     ret = 0;
 
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 9c72c10..9096b3c 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -4100,6 +4100,7 @@ qemuBuildCpuArgStr(const struct qemud_driver *driver,
         int hasSVM;
 
         if (!host ||
+            !host->model ||
             (ncpus = qemuCapsGetCPUDefinitions(caps, &cpus)) == 0) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                            _("CPU specification not supported by hypervisor"));
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 427258d..cbc621f 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -1227,7 +1227,9 @@ qemuDomainDefFormatBuf(struct qemud_driver *driver,
     if ((flags & VIR_DOMAIN_XML_UPDATE_CPU) &&
         def_cpu &&
         (def_cpu->mode != VIR_CPU_MODE_CUSTOM || def_cpu->model)) {
-        if (!driver->caps || !driver->caps->host.cpu) {
+        if (!driver->caps ||
+            !driver->caps->host.cpu ||
+            !driver->caps->host.cpu->model) {
             virReportError(VIR_ERR_OPERATION_FAILED,
                            "%s", _("cannot get host CPU capabilities"));
             goto cleanup;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index adfbfa6..76730c6 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -10180,7 +10180,8 @@ qemuCPUCompare(virConnectPtr conn,
     if (!driver->caps) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
                        "%s", _("cannot get host capabilities"));
-    } else if (!driver->caps->host.cpu) {
+    } else if (!driver->caps->host.cpu ||
+               !driver->caps->host.cpu->model) {
         VIR_WARN("cannot get host CPU capabilities");
         ret = VIR_CPU_COMPARE_INCOMPATIBLE;
     } else {
-- 
1.7.12.4