From 247357cc292a83c8628592562cbb4fa621cdc5b0 Mon Sep 17 00:00:00 2001
From: Martin Kletzander <mkletzan@redhat.com>
Date: Fri, 20 Dec 2024 12:28:24 +0100
Subject: [PATCH] qemu: Add support for direct and extended tlbflush features

They require special handling since they are dependent on the basic
tlbflush feature itself and therefore are not handled automatically as
part of virDomainHyperv enum, just like the stimer-direct feature.

Resolves: https://issues.redhat.com/browse/RHEL-7122
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
---
 src/qemu/qemu_command.c                       |  6 +++++
 src/qemu/qemu_process.c                       | 24 +++++++++++++++++++
 .../qemuxmlconfdata/hyperv.x86_64-latest.args |  2 +-
 tests/qemuxmlconfdata/hyperv.xml              |  5 +++-
 4 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index dcb9c4934e..1f28de6194 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -6350,6 +6350,12 @@ qemuBuildCpuCommandLine(virCommand *cmd,
                 if ((i == VIR_DOMAIN_HYPERV_STIMER) &&
                     (def->hyperv_stimer_direct == VIR_TRISTATE_SWITCH_ON))
                     virBufferAsprintf(&buf, ",%s=on", VIR_CPU_x86_HV_STIMER_DIRECT);
+                if (i == VIR_DOMAIN_HYPERV_TLBFLUSH) {
+                    if (def->hyperv_tlbflush_direct == VIR_TRISTATE_SWITCH_ON)
+                        virBufferAsprintf(&buf, ",%s=on", VIR_CPU_x86_HV_TLBFLUSH_DIRECT);
+                    if (def->hyperv_tlbflush_extended == VIR_TRISTATE_SWITCH_ON)
+                        virBufferAsprintf(&buf, ",%s=on", VIR_CPU_x86_HV_TLBFLUSH_EXT);
+                }
                 break;
 
             case VIR_DOMAIN_HYPERV_SPINLOCKS:
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index c72886503b..6db48b0e7b 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -4281,6 +4281,30 @@ qemuProcessVerifyHypervFeatures(virDomainDef *def,
                                "direct");
                 return -1;
             }
+            if (i == VIR_DOMAIN_HYPERV_TLBFLUSH) {
+                if (def->hyperv_tlbflush_direct == VIR_TRISTATE_SWITCH_ON) {
+                    rc = virCPUDataCheckFeature(cpu, VIR_CPU_x86_HV_TLBFLUSH_DIRECT);
+                    if (rc < 0)
+                        return -1;
+                    if (rc == 0) {
+                        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                                       _("host doesn't support hyperv tlbflush '%1$s' feature"),
+                                       "direct");
+                        return -1;
+                    }
+                }
+                if (def->hyperv_tlbflush_extended == VIR_TRISTATE_SWITCH_ON) {
+                    rc = virCPUDataCheckFeature(cpu, VIR_CPU_x86_HV_TLBFLUSH_EXT);
+                    if (rc < 0)
+                        return -1;
+                    if (rc == 0) {
+                        virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                                       _("host doesn't support hyperv tlbflush '%1$s' feature"),
+                                       "extended");
+                        return -1;
+                    }
+                }
+            }
             continue;
         }
 
diff --git a/tests/qemuxmlconfdata/hyperv.x86_64-latest.args b/tests/qemuxmlconfdata/hyperv.x86_64-latest.args
index 2aafafb340..5a32b80e71 100644
--- a/tests/qemuxmlconfdata/hyperv.x86_64-latest.args
+++ b/tests/qemuxmlconfdata/hyperv.x86_64-latest.args
@@ -12,7 +12,7 @@ XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain--1-QEMUGuest1/.config \
 -object '{"qom-type":"secret","id":"masterKey0","format":"raw","file":"/var/lib/libvirt/qemu/domain--1-QEMUGuest1/master-key.aes"}' \
 -machine pc,usb=off,dump-guest-core=off,memory-backend=pc.ram,acpi=on \
 -accel tcg \
--cpu 'qemu64,hv-relaxed=on,hv-vapic=on,hv-spinlocks=0x2fff,hv-vpindex=on,hv-runtime=on,hv-synic=on,hv-stimer=on,hv-reset=on,hv-vendor-id=KVM Hv,hv-frequencies=on,hv-reenlightenment=on,hv-tlbflush=on,hv-ipi=on,hv-evmcs=on,hv-avic=on,hv-emsr-bitmap=on,hv-xmm-input=on' \
+-cpu 'qemu64,hv-relaxed=on,hv-vapic=on,hv-spinlocks=0x2fff,hv-vpindex=on,hv-runtime=on,hv-synic=on,hv-stimer=on,hv-reset=on,hv-vendor-id=KVM Hv,hv-frequencies=on,hv-reenlightenment=on,hv-tlbflush=on,hv-tlbflush-direct=on,hv-tlbflush-ext=on,hv-ipi=on,hv-evmcs=on,hv-avic=on,hv-emsr-bitmap=on,hv-xmm-input=on' \
 -m size=219136k \
 -object '{"qom-type":"memory-backend-ram","id":"pc.ram","size":224395264}' \
 -overcommit mem-lock=off \
diff --git a/tests/qemuxmlconfdata/hyperv.xml b/tests/qemuxmlconfdata/hyperv.xml
index a1e3cbbdf8..8c323f6578 100644
--- a/tests/qemuxmlconfdata/hyperv.xml
+++ b/tests/qemuxmlconfdata/hyperv.xml
@@ -22,7 +22,10 @@
       <vendor_id state='on' value='KVM Hv'/>
       <frequencies state='on'/>
       <reenlightenment state='on'/>
-      <tlbflush state='on'/>
+      <tlbflush state='on'>
+        <direct state='on'/>
+        <extended state='on'/>
+      </tlbflush>
       <ipi state='on'/>
       <evmcs state='on'/>
       <avic state='on'/>