[libvirt] [PATCHv3 2/4] qemu: add support for hv_crash feature as a panic device

[Dmitry Andreev]

Panic device type used depends on 'model' attribute.

If no model is specified then device type depends on hypervisor
and guest arch. 'pseries' model is used for pSeries guest and
'isa' model is used in other cases.

XML:
<devices>
  <panic model='hyperv'/>
</devices>

QEMU command line:
qemu -cpu <cpu_model>,hv_crash
---
 src/qemu/qemu_command.c | 64 +++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 59 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 792ada3..2d0cec0 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -7623,6 +7623,16 @@ qemuBuildCpuArgStr(virQEMUDriverPtr driver,
         }
     }
 
+    if (def->panic &&
+        def->panic->model == VIR_DOMAIN_PANIC_MODEL_HYPERV) {
+        if (!have_cpu) {
+            virBufferAdd(&buf, default_model, -1);
+            have_cpu = true;
+        }
+
+        virBufferAddLit(&buf, ",hv_crash");
+    }
+
     if (def->features[VIR_DOMAIN_FEATURE_KVM] == VIR_TRISTATE_SWITCH_ON) {
         if (!have_cpu) {
             virBufferAdd(&buf, default_model, -1);
@@ -11150,17 +11160,49 @@ qemuBuildCommandLine(virConnectPtr conn,
     }
 
     if (def->panic) {
-        if (ARCH_IS_PPC64(def->os.arch) && STRPREFIX(def->os.machine, "pseries")) {
-            /* For pSeries guests, the firmware provides the same
-             * functionality as the pvpanic device. The address
+        virDomainPanicModel model = def->panic->model;
+
+        if (model == VIR_DOMAIN_PANIC_MODEL_DEFAULT) {
+            if (ARCH_IS_PPC64(def->os.arch) &&
+                STRPREFIX(def->os.machine, "pseries"))
+                model = VIR_DOMAIN_PANIC_MODEL_PSERIES;
+            else
+                model = VIR_DOMAIN_PANIC_MODEL_ISA;
+        }
+
+        switch (model) {
+        case VIR_DOMAIN_PANIC_MODEL_HYPERV:
+            /* Panic with model 'hyperv' is not a device, it should
+             * be configured in cpu commandline. The address
              * cannot be configured by the user */
             if (def->panic->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE) {
                 virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                                _("setting the panic device address is not "
-                                 "supported for pSeries guests"));
+                                 "supported for model 'hyperv'"));
                 goto error;
             }
-        } else {
+            break;
+
+        case VIR_DOMAIN_PANIC_MODEL_PSERIES:
+            if (ARCH_IS_PPC64(def->os.arch) && STRPREFIX(def->os.machine, "pseries")) {
+                /* For pSeries guests, the firmware provides the same
+                 * functionality as the pvpanic device. The address
+                 * cannot be configured by the user */
+                if (def->panic->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE) {
+                    virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                                   _("setting the panic device address is not "
+                                     "supported for model 'pseries'"));
+                    goto error;
+                }
+            } else {
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                               _("only pSeries guests support panic device "
+                                 "with model 'pseries'"));
+                goto error;
+            }
+            break;
+
+        case VIR_DOMAIN_PANIC_MODEL_ISA:
             if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_PANIC)) {
                 virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                                _("the QEMU binary does not support the "
@@ -11185,6 +11227,11 @@ qemuBuildCommandLine(virConnectPtr conn,
                                  "with ISA address type"));
                 goto error;
             }
+
+        /* default model value was changed before switch */
+        case VIR_DOMAIN_PANIC_MODEL_DEFAULT:
+        case VIR_DOMAIN_PANIC_MODEL_LAST:
+            break;
         }
     }
 
@@ -12534,6 +12581,13 @@ qemuParseCommandLineCPU(virDomainDefPtr dom,
                 if (virCPUDefAddFeature(cpu, feature, policy) < 0)
                     goto cleanup;
             }
+        } else if (STREQ(tokens[i], "hv_crash")) {
+            virDomainPanicDefPtr panic;
+            if (VIR_ALLOC(panic) < 0)
+                goto cleanup;
+
+            panic->model = VIR_DOMAIN_PANIC_MODEL_HYPERV;
+            dom->panic = panic;
         } else if (STRPREFIX(tokens[i], "hv_")) {
             const char *token = tokens[i] + 3; /* "hv_" */
             const char *feature, *value;
-- 
1.8.3.1