[libvirt] [v0.10.2-maint][PATCH] qemu: Always format CPU topology

[Michal Privoznik]

From: Jiri Denemark <jdenemar at redhat.com>

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.
(cherry picked from commit f1c70100409562c3f402392aa667732e5f89a2c4)

Conflicts:

    src/qemu/qemu_capabilities.c
    src/qemu/qemu_command.c

    The new code uses capabilities caching.
---

I am not sure about the correct process of this. So if there are some pointers ....

 src/qemu/qemu_capabilities.c |    6 +++---
 src/qemu/qemu_domain.c       |    4 +++-
 src/qemu/qemu_driver.c       |    3 ++-
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 37f1a2b..b1ef1b9 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -844,6 +844,7 @@ qemuCapsInitGuest(virCapsPtr caps,
     guest->arch.defaultInfo.emulator_mtime = binary_mtime;
 
     if (caps->host.cpu &&
+        caps->host.cpu->model &&
         qemuCapsProbeCPUModels(binary, NULL, info->arch, &ncpus, NULL) == 0 &&
         ncpus > 0 &&
         !virCapabilitiesAddGuestFeature(guest, "cpuselection", 1, 0))
@@ -973,12 +974,11 @@ 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_domain.c b/src/qemu/qemu_domain.c
index 17ae3b9..e23ff11 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -1233,7 +1233,9 @@ 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 0258dbb..c1c8fa4 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -10083,7 +10083,8 @@ 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 {
-- 
1.7.8.6