qemu: Allow enabling/disabling features with host-passthrough

QEMU supports feature specification with -cpu host and we just skip
using that.  Since QEMU developers themselves would like to use this
feature, this patch modifies the code to work.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1178850

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>

diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 0df2b76ee4670649a46c07bef6a0b0b5673f75ba..0c3343e2883d080aee005a1209b24218119835f2 100644 (file)
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -982,6 +982,7 @@
 
 <pre>
   &lt;cpu mode='host-passthrough'/&gt;
+    &lt;feature policy='disable' name='lahf_lm'/&gt;
   ...</pre>
 
     <p>
@@ -1083,8 +1084,8 @@
           the same as the host CPU even in the aspects that libvirt does not
           understand. Though the downside of this mode is that the guest
           environment cannot be reproduced on different hardware. Thus, if you
-          hit any bugs, you are on your own. Neither <code>model</code> nor
-          <code>feature</code> elements are allowed in this mode.</dd>
+          hit any bugs, you are on your own. Further details of that CPU can
+          be changed using <code>feature</code> elements.</dd>
         </dl>
 
         In both <code>host-model</code> and <code>host-passthrough</code>

diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 879e064250d868833a0cd74af25dc04d5bc30ed9..85b370975979cf4c6f694d6d7f577f25fc0e0672 100644 (file)
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -4088,50 +4088,29 @@
       -->
   <define name="cpu">
     <element name="cpu">
-      <choice>
-        <group>
-          <interleave>
-            <optional>
-              <ref name="cpuTopology"/>
-            </optional>
-            <optional>
-              <ref name="cpuNuma"/>
-            </optional>
-          </interleave>
-        </group>
-        <group>
-          <ref name="cpuMode"/>
-          <interleave>
-            <optional>
-              <ref name="cpuModel"/>
-            </optional>
-            <optional>
-              <ref name="cpuNuma"/>
-            </optional>
-          </interleave>
-        </group>
-        <group>
-          <optional>
-            <ref name="cpuMode"/>
-          </optional>
-          <ref name="cpuMatch"/>
-          <interleave>
-            <ref name="cpuModel"/>
-            <optional>
-              <ref name="cpuVendor"/>
-            </optional>
-            <optional>
-              <ref name="cpuTopology"/>
-            </optional>
-            <zeroOrMore>
-              <ref name="cpuFeature"/>
-            </zeroOrMore>
-            <optional>
-              <ref name="cpuNuma"/>
-            </optional>
-          </interleave>
-        </group>
-      </choice>
+      <optional>
+        <ref name="cpuMode"/>
+      </optional>
+      <optional>
+        <ref name="cpuMatch"/>
+      </optional>
+      <interleave>
+        <optional>
+          <ref name="cpuModel"/>
+        </optional>
+        <optional>
+          <ref name="cpuVendor"/>
+        </optional>
+        <optional>
+          <ref name="cpuTopology"/>
+        </optional>
+        <zeroOrMore>
+          <ref name="cpuFeature"/>
+        </zeroOrMore>
+        <optional>
+          <ref name="cpuNuma"/>
+        </optional>
+      </interleave>
     </element>
   </define>
 

diff --git a/src/conf/cpu_conf.c b/src/conf/cpu_conf.c
index 3af0f443c1e5459c2749fe32bfdb71999bb245ac..31fb45883964163b945c6043ad49b07027727dd3 100644 (file)
--- a/src/conf/cpu_conf.c
+++ b/src/conf/cpu_conf.c
@@ -1,7 +1,7 @@
 /*
  * cpu_conf.c: CPU XML handling
  *
- * Copyright (C) 2009-2014 Red Hat, Inc.
+ * Copyright (C) 2009-2015 Red Hat, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -366,12 +366,8 @@ virCPUDefParseXML(xmlNodePtr node,
         goto error;
 
     if (n > 0) {
-        if (!def->model && def->mode == VIR_CPU_MODE_HOST_PASSTHROUGH) {
-            /* silently ignore incorrectly formatted features generated
-             * by older libvirt */
-            goto cleanup;
-        }
-        if (!def->model && def->mode != VIR_CPU_MODE_HOST_MODEL) {
+        if (!def->model && def->mode != VIR_CPU_MODE_HOST_MODEL &&
+            def->mode != VIR_CPU_MODE_HOST_PASSTHROUGH) {
             virReportError(VIR_ERR_XML_ERROR, "%s",
                            _("Non-empty feature list specified without "
                              "CPU model"));
@@ -623,6 +619,7 @@ virCPUDefFormatBuf(virBufferPtr buf,
 
     if (!def->model &&
         def->mode != VIR_CPU_MODE_HOST_MODEL &&
+        def->mode != VIR_CPU_MODE_HOST_PASSTHROUGH &&
         def->nfeatures) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                        _("Non-empty feature list specified without CPU model"));
@@ -663,30 +660,32 @@ virCPUDefFormatBuf(virBufferPtr buf,
         virBufferAddLit(buf, "/>\n");
     }
 
-    for (i = 0; formatModel && i < def->nfeatures; i++) {
-        virCPUFeatureDefPtr feature = def->features + i;
+    if (formatModel || def->mode == VIR_CPU_MODE_HOST_PASSTHROUGH) {
+        for (i = 0; i < def->nfeatures; i++) {
+            virCPUFeatureDefPtr feature = def->features + i;
 
-        if (!feature->name) {
-            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
-                           _("Missing CPU feature name"));
-            return -1;
-        }
+            if (!feature->name) {
+                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                               _("Missing CPU feature name"));
+                return -1;
+            }
 
-        if (def->type == VIR_CPU_TYPE_GUEST) {
-            const char *policy;
+            if (def->type == VIR_CPU_TYPE_GUEST) {
+                const char *policy;
 
-            policy = virCPUFeaturePolicyTypeToString(feature->policy);
-            if (!policy) {
-                virReportError(VIR_ERR_INTERNAL_ERROR,
-                               _("Unexpected CPU feature policy %d"),
-                               feature->policy);
-                return -1;
+                policy = virCPUFeaturePolicyTypeToString(feature->policy);
+                if (!policy) {
+                    virReportError(VIR_ERR_INTERNAL_ERROR,
+                                   _("Unexpected CPU feature policy %d"),
+                                   feature->policy);
+                    return -1;
+                }
+                virBufferAsprintf(buf, "<feature policy='%s' name='%s'/>\n",
+                                  policy, feature->name);
+            } else {
+                virBufferAsprintf(buf, "<feature name='%s'/>\n",
+                                  feature->name);
             }
-            virBufferAsprintf(buf, "<feature policy='%s' name='%s'/>\n",
-                              policy, feature->name);
-        } else {
-            virBufferAsprintf(buf, "<feature name='%s'/>\n",
-                              feature->name);
         }
     }
 

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 101b88af4886bfe5b39de29a73f98b6f41b43297..3346e95e1d4ee0847c2e7457dcb70a3e7b806566 100644 (file)
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -6115,6 +6115,7 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
     virCPUDefPtr host = NULL;
     virCPUDefPtr guest = NULL;
     virCPUDefPtr cpu = NULL;
+    virCPUDefPtr featCpu = NULL;
     size_t ncpus = 0;
     char **cpus = NULL;
     virCPUDataPtr data = NULL;
@@ -6122,8 +6123,9 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
     virCPUCompareResult cmp;
     const char *preferred;
     virCapsPtr caps = NULL;
-    bool compareAgainstHost = (def->virtType == VIR_DOMAIN_VIRT_KVM ||
-        def->cpu->mode != VIR_CPU_MODE_CUSTOM);
+    bool compareAgainstHost = ((def->virtType == VIR_DOMAIN_VIRT_KVM ||
+                                def->cpu->mode != VIR_CPU_MODE_CUSTOM) &&
+                               def->cpu->mode != VIR_CPU_MODE_HOST_PASSTHROUGH);
 
     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
         goto cleanup;
@@ -6141,7 +6143,7 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
     if (!(cpu = virCPUDefCopy(def->cpu)))
         goto cleanup;
 
-    if (cpu->mode != VIR_CPU_MODE_CUSTOM &&
+    if (cpu->mode == VIR_CPU_MODE_HOST_MODEL &&
         !migrating &&
         cpuUpdate(cpu, host) < 0)
         goto cleanup;
@@ -6200,6 +6202,8 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
         if (ARCH_IS_PPC64(def->os.arch) &&
             cpu->mode == VIR_CPU_MODE_HOST_MODEL) {
             virBufferAsprintf(buf, ",compat=%s", def->cpu->model);
+        } else {
+            featCpu = cpu;
         }
 
     } else {
@@ -6225,18 +6229,21 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
             if (VIR_STRDUP(guest->model, cpu->model) < 0)
                 goto cleanup;
         }
-
         virBufferAdd(buf, guest->model, -1);
         if (guest->vendor_id)
             virBufferAsprintf(buf, ",vendor=%s", guest->vendor_id);
-        for (i = 0; i < guest->nfeatures; i++) {
+        featCpu = guest;
+    }
+
+    if (featCpu) {
+        for (i = 0; i < featCpu->nfeatures; i++) {
             char sign;
-            if (guest->features[i].policy == VIR_CPU_FEATURE_DISABLE)
+            if (featCpu->features[i].policy == VIR_CPU_FEATURE_DISABLE)
                 sign = '-';
             else
                 sign = '+';
 
-            virBufferAsprintf(buf, ",%c%s", sign, guest->features[i].name);
+            virBufferAsprintf(buf, ",%c%s", sign, featCpu->features[i].name);
         }
     }
 

diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features-invalid.args b/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features.args
similarity index 91%
rename from tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features-invalid.args
rename to tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features.args
index 18c1dce084c6a2f7fa498837bbeecf4bf1aaa3b0..88a25bf4324fb1de3766774a0af3c1697b3a4d3c 100644 (file)
--- a/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features-invalid.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features.args
@@ -8,7 +8,7 @@ IO_DRV=none \
 /usr/bin/qemu \
 -S \
 -M pc \
--cpu host \
+-cpu host,+abm,+ds,-invtsc \
 -m 214 \
 -smp 1 \
 -nographic \

diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features-invalid.xml b/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features.xml
similarity index 57%
rename from tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features-invalid.xml
rename to tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features.xml
index b5f532643d2c29d25d7e0d1050d446a83b89658e..e807dbdeff2060787a35e97b9b559aaeb842f022 100644 (file)
--- a/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features-invalid.xml
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-passthrough-features.xml
@@ -15,26 +15,8 @@
   </os>
   <cpu mode='host-passthrough'>
     <feature policy='require' name='abm'/>
-    <feature policy='require' name='pdpe1gb'/>
-    <feature policy='require' name='rdrand'/>
-    <feature policy='require' name='f16c'/>
-    <feature policy='require' name='osxsave'/>
-    <feature policy='require' name='pdcm'/>
-    <feature policy='require' name='xtpr'/>
-    <feature policy='require' name='tm2'/>
-    <feature policy='require' name='est'/>
-    <feature policy='require' name='smx'/>
-    <feature policy='require' name='vmx'/>
-    <feature policy='require' name='ds_cpl'/>
-    <feature policy='require' name='monitor'/>
-    <feature policy='require' name='dtes64'/>
-    <feature policy='require' name='pbe'/>
-    <feature policy='require' name='tm'/>
-    <feature policy='require' name='ht'/>
-    <feature policy='require' name='ss'/>
-    <feature policy='require' name='acpi'/>
-    <feature policy='require' name='ds'/>
-    <feature policy='require' name='vme'/>
+    <feature policy='force' name='ds'/>
+    <feature policy='disable' name='invtsc'/>
   </cpu>
   <clock offset='utc'/>
   <on_poweroff>destroy</on_poweroff>

diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index bce88a84a9fb59eb573f3840b840489380aed95d..1d0bd611d6562f65e99fd24a465fc7eca5340aa3 100644 (file)
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -1524,7 +1524,7 @@ mymain(void)
     DO_TEST_FAILURE("shmem-small-size", QEMU_CAPS_PCIDEVICE,
                     QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_IVSHMEM);
     DO_TEST_PARSE_ERROR("shmem-msi-only", NONE);
-    DO_TEST("cpu-host-passthrough-features-invalid", QEMU_CAPS_KVM, QEMU_CAPS_CPU_HOST);
+    DO_TEST("cpu-host-passthrough-features", QEMU_CAPS_KVM, QEMU_CAPS_CPU_HOST);
 
     virObjectUnref(driver.config);
     virObjectUnref(driver.caps);

diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index e1ec514b1ebf209ce0f34ec490536de14b4048b6..1166534d0e80cb3b9f633c410c370bf171a13b5f 100644 (file)
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -184,6 +184,7 @@ mymain(void)
     DO_TEST("clock-localtime");
     DO_TEST("cpu-kvmclock");
     DO_TEST("cpu-host-kvmclock");
+    DO_TEST("cpu-host-passthrough-features");
     DO_TEST("clock-catchup");
     DO_TEST("kvmclock");
     DO_TEST("clock-timer-hyperv-rtc");