From 26d33ed184f16a57b412360e4e75dbbcb9807c76 Mon Sep 17 00:00:00 2001
Message-Id: <26d33ed184f16a57b412360e4e75dbbcb9807c76@dist-git>
From: Jiri Denemark <jdenemar@redhat.com>
Date: Fri, 27 Mar 2015 12:48:40 +0100
Subject: [PATCH] RHEL: Hack around changed Broadwell/Haswell CPUs

RHEL-only

Upstream tried to solve the change of Broadwell and Haswell CPUs by
removing rtm and hle features from the corresponding CPU models for new
machine types. Then they reverted this and introduced new *-noTSX models
instead. However, the original fix was backported to RHEL.

This patch makes sure Broadwell and Haswell will always contain rtm and
hle features regardless on RHEL version or machine type used.

https://bugzilla.redhat.com/show_bug.cgi?id=1199446

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
---
 src/qemu/qemu_command.c                             | 21 +++++++++++++++++++++
 .../qemuxml2argvdata/qemuxml2argv-cpu-Haswell.args  |  2 +-
 .../qemuxml2argv-cpu-host-model-cmt.args            |  3 ++-
 .../qemuxml2argv-cpu-tsc-frequency.args             |  2 +-
 4 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 64d2d7105..1a2984e56 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -6768,6 +6768,8 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
     size_t i;
     virCapsPtr caps = NULL;
     virCPUDefPtr cpu = def->cpu;
+    bool hle = false;
+    bool rtm = false;
 
     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
         goto cleanup;
@@ -6822,6 +6824,11 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
         virBufferAsprintf(buf, ",vendor=%s", cpu->vendor_id);
 
     for (i = 0; i < cpu->nfeatures; i++) {
+        if (STREQ("rtm", cpu->features[i].name))
+            rtm = true;
+        if (STREQ("hle", cpu->features[i].name))
+            hle = true;
+
         switch ((virCPUFeaturePolicy) cpu->features[i].policy) {
         case VIR_CPU_FEATURE_FORCE:
         case VIR_CPU_FEATURE_REQUIRE:
@@ -6845,6 +6852,20 @@ qemuBuildCpuModelArgStr(virQEMUDriverPtr driver,
         }
     }
 
+    /* Some versions of qemu-kvm in RHEL provide Broadwell and Haswell CPU
+     * models which lack rtm and hle features when used with some machine
+     * types. Let's make sure Broadwell and Haswell will always have these
+     * features. But only if the features were not explicitly mentioned in
+     * the guest CPU definition.
+     */
+    if (STREQ_NULLABLE(cpu->model, "Broadwell") ||
+        STREQ_NULLABLE(cpu->model, "Haswell")) {
+        if (!rtm)
+            virBufferAddLit(buf, ",+rtm");
+        if (!hle)
+            virBufferAddLit(buf, ",+hle");
+    }
+
     ret = 0;
  cleanup:
     virObjectUnref(caps);
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cpu-Haswell.args b/tests/qemuxml2argvdata/qemuxml2argv-cpu-Haswell.args
index ef0e68b14..2e74a6703 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-cpu-Haswell.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cpu-Haswell.args
@@ -8,7 +8,7 @@ QEMU_AUDIO_DRV=none \
 -name QEMUGuest1 \
 -S \
 -M pc \
--cpu Haswell \
+-cpu Haswell,+rtm,+hle \
 -m 214 \
 -smp 6,sockets=6,cores=1,threads=1 \
 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-model-cmt.args b/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-model-cmt.args
index 7ae4ac5ad..e02f996ee 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-model-cmt.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cpu-host-model-cmt.args
@@ -9,7 +9,8 @@ QEMU_AUDIO_DRV=none \
 -S \
 -M pc \
 -cpu Haswell,+vme,+ds,+acpi,+ss,+ht,+tm,+pbe,+dtes64,+monitor,+ds_cpl,+vmx,\
-+smx,+est,+tm2,+xtpr,+pdcm,+osxsave,+f16c,+rdrand,+pdpe1gb,+abm,+lahf_lm \
++smx,+est,+tm2,+xtpr,+pdcm,+osxsave,+f16c,+rdrand,+pdpe1gb,+abm,+lahf_lm,+rtm,\
++hle \
 -m 214 \
 -smp 6,sockets=6,cores=1,threads=1 \
 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-cpu-tsc-frequency.args b/tests/qemuxml2argvdata/qemuxml2argv-cpu-tsc-frequency.args
index 50223fab2..cd9a3ef16 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-cpu-tsc-frequency.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-cpu-tsc-frequency.args
@@ -10,7 +10,7 @@ QEMU_AUDIO_DRV=none \
 -M pc \
 -cpu Haswell,+vme,+ds,+acpi,+ss,+ht,+tm,+pbe,+dtes64,+monitor,+ds_cpl,+vmx,\
 +smx,+est,+tm2,+xtpr,+pdcm,+osxsave,+f16c,+rdrand,+pdpe1gb,+abm,+lahf_lm,\
-+invtsc,tsc-frequency=3504000000 \
++invtsc,+rtm,+hle,tsc-frequency=3504000000 \
 -m 214 \
 -smp 1,sockets=1,cores=1,threads=1 \
 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
-- 
2.12.2