qemu: command: wire up usage of q35/ich9 disable s3/s4

If the q35 specific disable s3/s4 setting isn't supported, fallback to
specifying the PIIX setting, which is the previous behavior. It doesn't
have any effect, but qemu will just warn about it rather than error:

  qemu-system-x86_64: Warning: global PIIX4_PM.disable_s3=1 not used
  qemu-system-x86_64: Warning: global PIIX4_PM.disable_s4=1 not used

Since it doesn't error, I don't think we should either, since there
may be configs in the wild that already have q35 + disable_s3/4 (via
virt-manager)

src/qemu/qemu_command.c

@@ -9805,26 +9805,42 @@ qemuBuildCommandLine(virConnectPtr conn,
             virCommandAddArg(cmd, "-no-acpi");
     }
 
+    /* We fall back to PIIX4_PM even for q35, since it's what we did
+       pre-q35-pm support. QEMU starts up fine (with a warning) if
+       mixing PIIX PM and -M q35. Starting to reject things here
+       could mean we refuse to start existing configs in the wild.*/
     if (def->pm.s3) {
-        if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_PIIX_DISABLE_S3)) {
+        const char *pm_object = "PIIX4_PM";
+
+        if (qemuDomainMachineIsQ35(def) &&
+            virQEMUCapsGet(qemuCaps, QEMU_CAPS_ICH9_DISABLE_S3)) {
+            pm_object = "ICH9-LPC";
+        } else if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_PIIX_DISABLE_S3)) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            "%s", _("setting ACPI S3 not supported"));
             goto error;
         }
+
         virCommandAddArg(cmd, "-global");
-        virCommandAddArgFormat(cmd, "PIIX4_PM.disable_s3=%d",
-                               def->pm.s3 == VIR_TRISTATE_BOOL_NO);
+        virCommandAddArgFormat(cmd, "%s.disable_s3=%d",
+                               pm_object, def->pm.s3 == VIR_TRISTATE_BOOL_NO);
     }
 
     if (def->pm.s4) {
-        if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_PIIX_DISABLE_S4)) {
+        const char *pm_object = "PIIX4_PM";
+
+        if (qemuDomainMachineIsQ35(def) &&
+            virQEMUCapsGet(qemuCaps, QEMU_CAPS_ICH9_DISABLE_S4)) {
+            pm_object = "ICH9-LPC";
+        } else if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_PIIX_DISABLE_S4)) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            "%s", _("setting ACPI S4 not supported"));
             goto error;
         }
+
         virCommandAddArg(cmd, "-global");
-        virCommandAddArgFormat(cmd, "PIIX4_PM.disable_s4=%d",
-                               def->pm.s4 == VIR_TRISTATE_BOOL_NO);
+        virCommandAddArgFormat(cmd, "%s.disable_s4=%d",
+                               pm_object, def->pm.s4 == VIR_TRISTATE_BOOL_NO);
     }
 
     /*

tests/qemuxml2argvdata/qemuxml2argv-q35-pm-disable-fallback.args

@@ -0,0 +1,23 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-kvm \
+-name q35 \
+-S \
+-M pc-q35-2.5 \
+-m 1024 \
+-smp 1 \
+-uuid 56f5055c-1b8d-490c-844a-ad646a1caaaa \
+-nographic \
+-nodefaults \
+-monitor unix:/tmp/test-monitor,server,nowait \
+-no-acpi \
+-global PIIX4_PM.disable_s3=1 \
+-global PIIX4_PM.disable_s4=1 \
+-boot n \
+-device i82801b11-bridge,id=pci.1,bus=pcie.0,addr=0x1e \
+-device pci-bridge,chassis_nr=2,id=pci.2,bus=pci.1,addr=0x1 \
+-device virtio-balloon-pci,id=balloon0,bus=pci.2,addr=0x1

tests/qemuxml2argvdata/qemuxml2argv-q35-pm-disable-fallback.xml

@@ -0,0 +1,18 @@
+<domain type='qemu'>
+  <name>q35</name>
+  <uuid>56f5055c-1b8d-490c-844a-ad646a1caaaa</uuid>
+  <memory unit='KiB'>1048576</memory>
+  <currentMemory unit='KiB'>1048576</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc-q35-2.5'>hvm</type>
+    <boot dev='network'/>
+  </os>
+  <pm>
+    <suspend-to-mem enabled='no'/>
+    <suspend-to-disk enabled='no'/>
+  </pm>
+  <devices>
+    <emulator>/usr/bin/qemu-kvm</emulator>
+  </devices>
+</domain>

tests/qemuxml2argvdata/qemuxml2argv-q35-pm-disable.args

@@ -0,0 +1,23 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-kvm \
+-name q35 \
+-S \
+-M pc-q35-2.5 \
+-m 1024 \
+-smp 1 \
+-uuid 56f5055c-1b8d-490c-844a-ad646a1caaaa \
+-nographic \
+-nodefaults \
+-monitor unix:/tmp/test-monitor,server,nowait \
+-no-acpi \
+-global ICH9-LPC.disable_s3=1 \
+-global ICH9-LPC.disable_s4=1 \
+-boot n \
+-device i82801b11-bridge,id=pci.1,bus=pcie.0,addr=0x1e \
+-device pci-bridge,chassis_nr=2,id=pci.2,bus=pci.1,addr=0x1 \
+-device virtio-balloon-pci,id=balloon0,bus=pci.2,addr=0x1

tests/qemuxml2argvdata/qemuxml2argv-q35-pm-disable.xml

@@ -0,0 +1,18 @@
+<domain type='qemu'>
+  <name>q35</name>
+  <uuid>56f5055c-1b8d-490c-844a-ad646a1caaaa</uuid>
+  <memory unit='KiB'>1048576</memory>
+  <currentMemory unit='KiB'>1048576</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc-q35-2.5'>hvm</type>
+    <boot dev='network'/>
+  </os>
+  <pm>
+    <suspend-to-mem enabled='no'/>
+    <suspend-to-disk enabled='no'/>
+  </pm>
+  <devices>
+    <emulator>/usr/bin/qemu-kvm</emulator>
+  </devices>
+</domain>

tests/qemuxml2argvtest.c

@@ -1506,6 +1506,15 @@ mymain(void)
             QEMU_CAPS_ICH9_AHCI,
             QEMU_CAPS_DEVICE_VIDEO_PRIMARY,
             QEMU_CAPS_VGA_QXL, QEMU_CAPS_DEVICE_QXL);
+    DO_TEST("q35-pm-disable",
+            QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_PCI_BRIDGE,
+            QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE, QEMU_CAPS_ICH9_AHCI,
+            QEMU_CAPS_PIIX_DISABLE_S3, QEMU_CAPS_PIIX_DISABLE_S4,
+            QEMU_CAPS_ICH9_DISABLE_S3, QEMU_CAPS_ICH9_DISABLE_S4);
+    DO_TEST("q35-pm-disable-fallback",
+            QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_PCI_BRIDGE,
+            QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE, QEMU_CAPS_ICH9_AHCI,
+            QEMU_CAPS_PIIX_DISABLE_S3, QEMU_CAPS_PIIX_DISABLE_S4);
     DO_TEST("pcie-root-port",
             QEMU_CAPS_DEVICE, QEMU_CAPS_DEVICE_PCI_BRIDGE,
             QEMU_CAPS_DEVICE_DMI_TO_PCI_BRIDGE,