qemu: add support for tsc.on_reboot element

QEMU 7.0.0 adds a new property tsc-clear-on-reset to x86 CPU, corresponding
to Libvirt's <tsc on_reboot="clear"/> element.  Plumb it in the validation,
command line handling and tests.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_capabilities.c

@@ -669,6 +669,7 @@ VIR_ENUM_IMPL(virQEMUCaps,
               /* 425 */
               "blockdev.nbd.tls-hostname", /* QEMU_CAPS_BLOCKDEV_NBD_TLS_HOSTNAME */
               "memory-backend-file.prealloc-threads", /* QEMU_CAPS_MEMORY_BACKEND_PREALLOC_THREADS */
+              "x86-cpu.tsc-clear-on-reset", /* QEMU_CAPS_X86_CPU_TSC_CLEAR_ON_RESET */
     );
 
 
@@ -1777,6 +1778,7 @@ static struct virQEMUCapsStringFlags virQEMUCapsObjectPropsMemoryBackendMemfd[]
 static struct virQEMUCapsStringFlags virQEMUCapsObjectPropsMaxCPU[] = {
     { "unavailable-features", QEMU_CAPS_CPU_UNAVAILABLE_FEATURES },
     { "kvm-no-adjvtime", QEMU_CAPS_CPU_KVM_NO_ADJVTIME },
+    { "tsc-clear-on-reset", QEMU_CAPS_X86_CPU_TSC_CLEAR_ON_RESET },
     { "migratable", QEMU_CAPS_CPU_MIGRATABLE },
 };
 

src/qemu/qemu_capabilities.h

@@ -644,6 +644,7 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */
     /* 425 */
     QEMU_CAPS_BLOCKDEV_NBD_TLS_HOSTNAME, /* tls hostname can be overriden for NBD clients */
     QEMU_CAPS_MEMORY_BACKEND_PREALLOC_THREADS, /* -object memory-backend-*.prealloc-threads */
+    QEMU_CAPS_X86_CPU_TSC_CLEAR_ON_RESET, /* x86-cpu.tsc-clear-on-reset */
 
     QEMU_CAPS_LAST /* this must always be the last item */
 } virQEMUCapsFlags;

src/qemu/qemu_command.c

@@ -6616,6 +6616,17 @@ qemuBuildCpuCommandLine(virCommand *cmd,
         case VIR_DOMAIN_TIMER_NAME_TSC:
             if (timer->frequency > 0)
                 virBufferAsprintf(&buf, ",tsc-frequency=%llu", timer->frequency);
+            switch (timer->reboot) {
+            case VIR_DOMAIN_TIMER_REBOOT_MODE_CLEAR:
+                virBufferAddLit(&buf, ",tsc-clear-on-reset=on");
+                break;
+            case VIR_DOMAIN_TIMER_REBOOT_MODE_KEEP:
+                virBufferAddLit(&buf, ",tsc-clear-on-reset=off");
+                break;
+            case VIR_DOMAIN_TIMER_REBOOT_MODE_DEFAULT:
+            case VIR_DOMAIN_TIMER_REBOOT_MODE_LAST:
+                break;
+            }
             break;
         case VIR_DOMAIN_TIMER_NAME_ARMVTIMER:
             switch (timer->tickpolicy) {

src/qemu/qemu_validate.c

@@ -396,10 +396,11 @@ static int
 qemuValidateDomainDefClockTimers(const virDomainDef *def,
                                  virQEMUCaps *qemuCaps)
 {
+    virDomainTimerDef *timer;
     size_t i;
 
     for (i = 0; i < def->clock.ntimers; i++) {
-        virDomainTimerDef *timer = def->clock.timers[i];
+        timer = def->clock.timers[i];
 
         switch ((virDomainTimerNameType)timer->name) {
         case VIR_DOMAIN_TIMER_NAME_PLATFORM:
@@ -409,20 +410,24 @@ qemuValidateDomainDefClockTimers(const virDomainDef *def,
             return -1;
 
         case VIR_DOMAIN_TIMER_NAME_TSC:
-        case VIR_DOMAIN_TIMER_NAME_KVMCLOCK:
+            if (!ARCH_IS_X86(def->os.arch) && timer->present == VIR_TRISTATE_BOOL_YES)
-        case VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK:
+                goto no_support;
-            if (!ARCH_IS_X86(def->os.arch) && timer->present == VIR_TRISTATE_BOOL_YES) {
+
+            if (timer->reboot != VIR_DOMAIN_TIMER_REBOOT_MODE_DEFAULT &&
+                !virQEMUCapsGet(qemuCaps, QEMU_CAPS_X86_CPU_TSC_CLEAR_ON_RESET)) {
                 virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
-                               _("Configuring the '%s' timer is not supported "
+                               _("Configuring the '%s' timer to reset on reboot is not supported with this QEMU binary"),
-                                 "for virtType=%s arch=%s machine=%s guests"),
+                               virDomainTimerNameTypeToString(timer->name));
-                               virDomainTimerNameTypeToString(timer->name),
-                               virDomainVirtTypeToString(def->virtType),
-                               virArchToString(def->os.arch),
-                               def->os.machine);
                 return -1;
             }
             break;
 
+        case VIR_DOMAIN_TIMER_NAME_KVMCLOCK:
+        case VIR_DOMAIN_TIMER_NAME_HYPERVCLOCK:
+            if (!ARCH_IS_X86(def->os.arch) && timer->present == VIR_TRISTATE_BOOL_YES)
+                goto no_support;
+            break;
+
         case VIR_DOMAIN_TIMER_NAME_LAST:
             break;
 
@@ -499,14 +504,7 @@ qemuValidateDomainDefClockTimers(const virDomainDef *def,
         case VIR_DOMAIN_TIMER_NAME_ARMVTIMER:
             if (def->virtType != VIR_DOMAIN_VIRT_KVM ||
                 !qemuDomainIsARMVirt(def)) {
-                virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                goto no_support;
-                               _("Configuring the '%s' timer is not supported "
-                                 "for virtType=%s arch=%s machine=%s guests"),
-                               virDomainTimerNameTypeToString(timer->name),
-                               virDomainVirtTypeToString(def->virtType),
-                               virArchToString(def->os.arch),
-                               def->os.machine);
-                return -1;
             }
             if (timer->present == VIR_TRISTATE_BOOL_NO) {
                 virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
@@ -540,6 +538,15 @@ qemuValidateDomainDefClockTimers(const virDomainDef *def,
     }
 
     return 0;
+
+ no_support:
+    virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                   _("Configuring the '%s' timer is not supported for virtType=%s arch=%s machine=%s guests"),
+                   virDomainTimerNameTypeToString(timer->name),
+                   virDomainVirtTypeToString(def->virtType),
+                   virArchToString(def->os.arch),
+                   def->os.machine);
+    return -1;
 }
 
 

tests/qemucapabilitiesdata/caps_7.0.0.x86_64.replies

@@ -28849,6 +28849,10 @@
     {
       "name": "sse4_1",
       "type": "bool"
+    },
+    {
+      "name": "tsc-clear-on-reset",
+      "type": "bool"
     }
   ],
   "id": "libvirt-41"

tests/qemucapabilitiesdata/caps_7.0.0.x86_64.xml

@@ -245,6 +245,7 @@
   <flag name='dirtyrate-param.mode'/>
   <flag name='blockdev.nbd.tls-hostname'/>
   <flag name='memory-backend-file.prealloc-threads'/>
+  <flag name='x86-cpu.tsc-clear-on-reset'/>
   <version>6002050</version>
   <kvmVersion>0</kvmVersion>
   <microcodeVersion>43100243</microcodeVersion>

tests/qemuxml2argvdata/cpu-tsc-clear-on-reset.args

@@ -0,0 +1,32 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/tmp/lib/domain--1-QEMUGuest1 \
+USER=test \
+LOGNAME=test \
+XDG_DATA_HOME=/tmp/lib/domain--1-QEMUGuest1/.local/share \
+XDG_CACHE_HOME=/tmp/lib/domain--1-QEMUGuest1/.cache \
+XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-x86_64 \
+-name guest=QEMUGuest1,debug-threads=on \
+-S \
+-object secret,id=masterKey0,format=raw,file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
+-machine pc,usb=off,dump-guest-core=off \
+-accel kvm \
+-cpu Haswell,vme=on,ds=on,acpi=on,ss=on,ht=on,tm=on,pbe=on,dtes64=on,monitor=on,ds-cpl=on,vmx=on,smx=on,est=on,tm2=on,xtpr=on,pdcm=on,f16c=on,rdrand=on,pdpe1gb=on,abm=on,lahf-lm=on,invtsc=on,tsc-clear-on-reset=on \
+-m 214 \
+-realtime mlock=off \
+-smp 1,sockets=1,cores=1,threads=1 \
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev socket,id=charmonitor,path=/tmp/lib/domain--1-QEMUGuest1/monitor.sock,server=on,wait=off \
+-mon chardev=charmonitor,id=monitor,mode=control \
+-rtc base=utc \
+-no-shutdown \
+-no-acpi \
+-boot strict=on \
+-usb \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x2 \
+-msg timestamp=on

tests/qemuxml2argvdata/cpu-tsc-clear-on-reset.x86_64-7.0.0.args

@@ -0,0 +1,34 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/tmp/lib/domain--1-QEMUGuest1 \
+USER=test \
+LOGNAME=test \
+XDG_DATA_HOME=/tmp/lib/domain--1-QEMUGuest1/.local/share \
+XDG_CACHE_HOME=/tmp/lib/domain--1-QEMUGuest1/.cache \
+XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
+/usr/bin/qemu-system-x86_64 \
+-name guest=QEMUGuest1,debug-threads=on \
+-S \
+-object '{"qom-type":"secret","id":"masterKey0","format":"raw","file":"/tmp/lib/domain--1-QEMUGuest1/master-key.aes"}' \
+-machine pc-i440fx-7.0,usb=off,dump-guest-core=off,memory-backend=pc.ram \
+-accel kvm \
+-cpu EPYC-Rome,x2apic=on,tsc-deadline=on,hypervisor=on,tsc-adjust=on,stibp=on,arch-capabilities=on,ssbd=on,xsaves=on,cmp-legacy=on,amd-ssbd=on,virt-ssbd=on,svme-addr-chk=on,rdctl-no=on,skip-l1dfl-vmentry=on,mds-no=on,pschange-mc-no=on,invtsc=on,tsc-clear-on-reset=on \
+-m 214 \
+-object '{"qom-type":"memory-backend-ram","id":"pc.ram","size":224395264}' \
+-overcommit mem-lock=off \
+-smp 1,sockets=1,cores=1,threads=1 \
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev socket,id=charmonitor,fd=1729,server=on,wait=off \
+-mon chardev=charmonitor,id=monitor,mode=control \
+-rtc base=utc \
+-no-shutdown \
+-no-acpi \
+-boot strict=on \
+-device '{"driver":"piix3-usb-uhci","id":"usb","bus":"pci.0","addr":"0x1.0x2"}' \
+-audiodev '{"id":"audio1","driver":"none"}' \
+-device '{"driver":"virtio-balloon-pci","id":"balloon0","bus":"pci.0","addr":"0x2"}' \
+-sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \
+-msg timestamp=on

tests/qemuxml2argvdata/cpu-tsc-clear-on-reset.xml

@@ -0,0 +1,35 @@
+<domain type='kvm'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <title>A description of the test machine.</title>
+  <description>
+      A test of qemu&apos;s minimal configuration.
+      This test also tests the description and title elements.
+  </description>
+  <memory unit='KiB'>219100</memory>
+  <currentMemory unit='KiB'>219100</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <cpu mode='host-model'>
+    <model fallback='allow'/>
+    <feature policy='require' name='invtsc'/>
+  </cpu>
+  <clock offset='utc'>
+    <timer name='tsc' on_reboot='clear'/>
+  </clock>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</emulator>
+    <controller type='usb' index='0'/>
+    <controller type='ide' index='0'/>
+    <controller type='pci' index='0' model='pci-root'/>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <memballoon model='virtio'/>
+  </devices>
+</domain>

tests/qemuxml2argvtest.c

@@ -2094,6 +2094,8 @@ mymain(void)
     DO_TEST("cpu-Haswell-noTSX", QEMU_CAPS_KVM);
     DO_TEST_NOCAPS("cpu-host-model-cmt");
     DO_TEST_CAPS_VER("cpu-host-model-cmt", "4.0.0");
+    DO_TEST("cpu-tsc-clear-on-reset", QEMU_CAPS_X86_CPU_TSC_CLEAR_ON_RESET);
+    DO_TEST_CAPS_VER("cpu-tsc-clear-on-reset", "7.0.0");
     DO_TEST("cpu-tsc-frequency", QEMU_CAPS_KVM);
     DO_TEST_CAPS_VER("cpu-tsc-frequency", "4.0.0");
     DO_TEST_CAPS_VER("cpu-translation", "4.0.0");