[libvirt PATCH v3 2/6] qemu: always use hyphens in hyperv feature names

[Daniel P. Berrangé]

QEMU switched from using underscores in x86 CPU features to hyphens
in the 2.8.0 series with two commits

  commit fc7dfd205f3287893c436d932a167bffa30579c8 (HEAD, refs/bisect/bad)
  Author: Eduardo Habkost <ehabkost at redhat.com>
  Date:   Fri Sep 30 15:49:40 2016 -0300

    target-i386: Remove underscores from feat_names arrays

  commit 54b8dc7c19cd781e96f1e9b001ca6001d804eb19
  Author: Eduardo Habkost <ehabkost at redhat.com>
  Date:   Fri Sep 30 15:49:38 2016 -0300

    target-i386: Register aliases for feature names with underscores

Libvirt names use underscores so we conditionally tranlate the
names when talking to new QEMU. Since the min QEMU was raised to
version 2.11.0, all QEMU versions we talk to expect hypens, so
the translation can be done unconditionally.

Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
---
 src/qemu/qemu_command.c                         | 8 +-------
 tests/qemuxml2argvdata/hyperv.x86_64-4.0.0.args | 2 +-
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 28bca1519c..3b82c64e72 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -6493,11 +6493,6 @@ qemuBuildCpuCommandLine(virCommand *cmd,
     }
 
     if (def->features[VIR_DOMAIN_FEATURE_HYPERV] == VIR_TRISTATE_SWITCH_ON) {
-        const char *hvPrefix = "hv-";
-
-        if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_CANONICAL_CPU_FEATURES))
-            hvPrefix = "hv_";
-
         for (i = 0; i < VIR_DOMAIN_HYPERV_LAST; i++) {
             switch ((virDomainHyperv) i) {
             case VIR_DOMAIN_HYPERV_RELAXED:
@@ -6513,8 +6508,7 @@ qemuBuildCpuCommandLine(virCommand *cmd,
             case VIR_DOMAIN_HYPERV_IPI:
             case VIR_DOMAIN_HYPERV_EVMCS:
                 if (def->hyperv_features[i] == VIR_TRISTATE_SWITCH_ON)
-                    virBufferAsprintf(&buf, ",%s%s",
-                                      hvPrefix,
+                    virBufferAsprintf(&buf, ",hv-%s",
                                       virDomainHypervTypeToString(i));
                 if ((i == VIR_DOMAIN_HYPERV_STIMER) &&
                     (def->hyperv_stimer_direct == VIR_TRISTATE_SWITCH_ON))
diff --git a/tests/qemuxml2argvdata/hyperv.x86_64-4.0.0.args b/tests/qemuxml2argvdata/hyperv.x86_64-4.0.0.args
index 100223b53a..32cc2fbff7 100644
--- a/tests/qemuxml2argvdata/hyperv.x86_64-4.0.0.args
+++ b/tests/qemuxml2argvdata/hyperv.x86_64-4.0.0.args
@@ -12,7 +12,7 @@ QEMU_AUDIO_DRV=none \
 -S \
 -object secret,id=masterKey0,format=raw,file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
 -machine pc-i440fx-4.0,accel=tcg,usb=off,dump-guest-core=off \
--cpu 'qemu32,hv_relaxed,hv_vapic,hv-spinlocks=0x2fff,hv_vpindex,hv_runtime,hv_synic,hv_stimer,hv_reset,hv-vendor-id=KVM Hv,hv_frequencies,hv_reenlightenment,hv_tlbflush,hv_ipi,hv_evmcs' \
+-cpu 'qemu32,hv-relaxed,hv-vapic,hv-spinlocks=0x2fff,hv-vpindex,hv-runtime,hv-synic,hv-stimer,hv-reset,hv-vendor-id=KVM Hv,hv-frequencies,hv-reenlightenment,hv-tlbflush,hv-ipi,hv-evmcs' \
 -m 214 \
 -overcommit mem-lock=off \
 -smp 6,sockets=6,cores=1,threads=1 \
-- 
2.31.1