libvirt/0012-qemu-Don-t-cache-microcode-version.patch

From: Jiri Denemark <jdenemar@redhat.com>
Date: Fri, 12 Apr 2019 21:21:05 +0200
Subject: [PATCH] qemu: Don't cache microcode version
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My earlier commit be46f61326 was incomplete. It removed caching of
microcode version in the CPU driver, which means the capabilities XML
will see the correct microcode version. But it is also cached in the
QEMU capabilities cache where it is used to detect whether we need to
reprobe QEMU. By missing the second place, the original commit
be46f61326 made the situation even worse since libvirt would report
correct microcode version while still using the old host CPU model
(visible in domain capabilities XML).

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
(cherry picked from commit 673c62a3b7855a0685d8f116e227c402720b9ee9)
---
 src/qemu/qemu_capabilities.c | 12 ++++++++----
 src/qemu/qemu_capabilities.h |  3 +--
 src/qemu/qemu_driver.c       |  9 +--------
 tests/testutilsqemu.c        |  2 +-
 4 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index b48bcbebee..e5b1c90253 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -4487,7 +4487,7 @@ virQEMUCapsNewData(const char *binary,
                                            priv->libDir,
                                            priv->runUid,
                                            priv->runGid,
-                                           priv->microcodeVersion,
+                                           virHostCPUGetMicrocodeVersion(),
                                            priv->kernelVersion);
 }
 
@@ -4570,8 +4570,7 @@ virFileCachePtr
 virQEMUCapsCacheNew(const char *libDir,
                     const char *cacheDir,
                     uid_t runUid,
-                    gid_t runGid,
-                    unsigned int microcodeVersion)
+                    gid_t runGid)
 {
     char *capsCacheDir = NULL;
     virFileCachePtr cache = NULL;
@@ -4595,7 +4594,6 @@ virQEMUCapsCacheNew(const char *libDir,
 
     priv->runUid = runUid;
     priv->runGid = runGid;
-    priv->microcodeVersion = microcodeVersion;
     priv->kvmUsable = VIR_TRISTATE_BOOL_ABSENT;
 
     if (uname(&uts) == 0 &&
@@ -4617,8 +4615,11 @@ virQEMUCapsPtr
 virQEMUCapsCacheLookup(virFileCachePtr cache,
                        const char *binary)
 {
+    virQEMUCapsCachePrivPtr priv = virFileCacheGetPriv(cache);
     virQEMUCapsPtr ret = NULL;
 
+    priv->microcodeVersion = virHostCPUGetMicrocodeVersion();
+
     ret = virFileCacheLookup(cache, binary);
 
     VIR_DEBUG("Returning caps %p for %s", ret, binary);
@@ -4672,6 +4673,7 @@ virQEMUCapsPtr
 virQEMUCapsCacheLookupByArch(virFileCachePtr cache,
                              virArch arch)
 {
+    virQEMUCapsCachePrivPtr priv = virFileCacheGetPriv(cache);
     virQEMUCapsPtr ret = NULL;
     const char *binaryFilters[] = {
         "qemu-system-",
@@ -4684,6 +4686,8 @@ virQEMUCapsCacheLookupByArch(virFileCachePtr cache,
     size_t i;
     size_t j;
 
+    priv->microcodeVersion = virHostCPUGetMicrocodeVersion();
+
     for (i = 0; i < ARRAY_CARDINALITY(binaryFilters); i++) {
         for (j = 0; j < ARRAY_CARDINALITY(archs); j++) {
             struct virQEMUCapsSearchData data = {
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index ba84052bca..a6a655ac0f 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -587,8 +587,7 @@ void virQEMUCapsFilterByMachineType(virQEMUCapsPtr qemuCaps,
 virFileCachePtr virQEMUCapsCacheNew(const char *libDir,
                                     const char *cacheDir,
                                     uid_t uid,
-                                    gid_t gid,
-                                    unsigned int microcodeVersion);
+                                    gid_t gid);
 virQEMUCapsPtr virQEMUCapsCacheLookup(virFileCachePtr cache,
                                       const char *binary);
 virQEMUCapsPtr virQEMUCapsCacheLookupCopy(virFileCachePtr cache,
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 36426cd65a..75d31efd14 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -585,8 +585,6 @@ qemuStateInitialize(bool privileged,
     char *hugepagePath = NULL;
     char *memoryBackingPath = NULL;
     size_t i;
-    virCPUDefPtr hostCPU = NULL;
-    unsigned int microcodeVersion = 0;
 
     if (VIR_ALLOC(qemu_driver) < 0)
         return -1;
@@ -809,15 +807,10 @@ qemuStateInitialize(bool privileged,
         run_gid = cfg->group;
     }
 
-    if ((hostCPU = virCPUProbeHost(virArchFromHost())))
-        microcodeVersion = hostCPU->microcodeVersion;
-    virCPUDefFree(hostCPU);
-
     qemu_driver->qemuCapsCache = virQEMUCapsCacheNew(cfg->libDir,
                                                      cfg->cacheDir,
                                                      run_uid,
-                                                     run_gid,
-                                                     microcodeVersion);
+                                                     run_gid);
     if (!qemu_driver->qemuCapsCache)
         goto error;
 
diff --git a/tests/testutilsqemu.c b/tests/testutilsqemu.c
index 1736bad032..e30c0599ad 100644
--- a/tests/testutilsqemu.c
+++ b/tests/testutilsqemu.c
@@ -740,7 +740,7 @@ int qemuTestDriverInit(virQEMUDriver *driver)
 
     /* Using /dev/null for libDir and cacheDir automatically produces errors
      * upon attempt to use any of them */
-    driver->qemuCapsCache = virQEMUCapsCacheNew("/dev/null", "/dev/null", 0, 0, 0);
+    driver->qemuCapsCache = virQEMUCapsCacheNew("/dev/null", "/dev/null", 0, 0);
     if (!driver->qemuCapsCache)
         goto error;