libvirt/0005-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)

Conflicts:
        src/qemu/qemu_capabilities.c
            - virQEMUCapsCacheLookupByArch refactoring (commits
              7948ad4129a and 1a3de67001c) are missing

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 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 a075677421..eaf369f5b1 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -4700,7 +4700,7 @@ virQEMUCapsNewData(const char *binary,
                                            priv->libDir,
                                            priv->runUid,
                                            priv->runGid,
-                                           priv->microcodeVersion,
+                                           virHostCPUGetMicrocodeVersion(),
                                            priv->kernelVersion);
 }
 
@@ -4783,8 +4783,7 @@ 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;
@@ -4808,7 +4807,6 @@ virQEMUCapsCacheNew(const char *libDir,
 
     priv->runUid = runUid;
     priv->runGid = runGid;
-    priv->microcodeVersion = microcodeVersion;
 
     if (uname(&uts) == 0 &&
         virAsprintf(&priv->kernelVersion, "%s %s", uts.release, uts.version) < 0)
@@ -4829,8 +4827,11 @@ 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);
@@ -4876,10 +4877,13 @@ virQEMUCapsPtr
 virQEMUCapsCacheLookupByArch(virFileCachePtr cache,
                              virArch arch)
 {
+    virQEMUCapsCachePrivPtr priv = virFileCacheGetPriv(cache);
     virQEMUCapsPtr ret = NULL;
     virArch target;
     struct virQEMUCapsSearchData data = { .arch = arch };
 
+    priv->microcodeVersion = virHostCPUGetMicrocodeVersion();
+
     ret = virFileCacheLookupByFunc(cache, virQEMUCapsCompareArch, &data);
     if (!ret) {
         /* If the first attempt at finding capabilities has failed, try
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index 3d3a978759..956babc7eb 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -574,8 +574,7 @@ 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 a0f7c71675..75f8699e7d 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -592,8 +592,6 @@ 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;
@@ -813,15 +811,10 @@ 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 8438613f28..4e53f03f9e 100644
--- a/tests/testutilsqemu.c
+++ b/tests/testutilsqemu.c
@@ -707,7 +707,7 @@ 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;