On Tue, Oct 05, 2021 at 18:07:03 +0100, Daniel P. Berrangé wrote:
> The -cpu arg gained support for feature=on|off syntax for the x86
> emulator in 2.4.0
>
> commit 38e5c119c2925812bd441450ab9e5e00fc79e662
> Author: Eduardo Habkost <ehabkost@xxxxxxxxxx>
> Date: Mon Mar 23 17:29:32 2015 -0300
>
> target-i386: Register QOM properties for feature flags
>
> Most other targets gained this syntax even earlier in 1.4.1
>
> commit 1590bbcb02921dfe8e3cf66e3a3aafd31193babf
> Author: Andreas Färber <afaerber@xxxxxxx>
> Date: Mon Mar 3 23:33:51 2014 +0100
>
> cpu: Implement CPUClass::parse_features() for the rest of CPUs
>
> CPUs who do not provide their own implementation of feature parsing
> will treat each option as a QOM property and set it to the supplied
> value.
>
> There appears no reason to keep supporting "+|-feature" syntax,
> given the current minimum QEMU version.
>
> Signed-off-by: Daniel P. Berrangé <berrange@xxxxxxxxxx>
> ---
[...]
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index eaa1e0deb9..a1dba1cb7e 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -6242,21 +6242,6 @@ qemuBuildGlobalControllerCommandLine(virCommand *cmd,
> }
>
>
> -static void
> -qemuBuildCpuFeature(virQEMUCaps *qemuCaps,
> - virBuffer *buf,
> - const char *name,
> - bool state)
> -{
> - name = virQEMUCapsCPUFeatureToQEMU(qemuCaps, name);
This function, which is no longer called ...
> -
> - if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_QUERY_CPU_MODEL_EXPANSION))
> - virBufferAsprintf(buf, ",%s=%s", name, state ? "on" : "off");
> - else
> - virBufferAsprintf(buf, ",%c%s", state ? '+' : '-', name);
> -}
> -
> -
> static int
> qemuBuildCpuModelArgStr(virQEMUDriver *driver,
> const virDomainDef *def,
> @@ -6332,12 +6317,12 @@ qemuBuildCpuModelArgStr(virQEMUDriver *driver,
> switch ((virCPUFeaturePolicy) cpu->features[i].policy) {
> case VIR_CPU_FEATURE_FORCE:
> case VIR_CPU_FEATURE_REQUIRE:
> - qemuBuildCpuFeature(qemuCaps, buf, cpu->features[i].name, true);
> + virBufferAsprintf(buf, ",%s=on", cpu->features[i].name);
> break;
>
> case VIR_CPU_FEATURE_DISABLE:
> case VIR_CPU_FEATURE_FORBID:
> - qemuBuildCpuFeature(qemuCaps, buf, cpu->features[i].name, false);
> + virBufferAsprintf(buf, ",%s=off", cpu->features[i].name);
... here ...
> break;
>
> case VIR_CPU_FEATURE_OPTIONAL:
[...]
> diff --git a/tests/qemuxml2argvdata/cpu-host-model.x86_64-5.0.0.args b/tests/qemuxml2argvdata/cpu-host-model.x86_64-5.0.0.args
> index 3ce594ba13..7f29bcd10d 100644
... is causing a change even on modern versions ...
> --- a/tests/qemuxml2argvdata/cpu-host-model.x86_64-5.0.0.args
> +++ b/tests/qemuxml2argvdata/cpu-host-model.x86_64-5.0.0.args
> @@ -11,7 +11,7 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
> -S \
> -object secret,id=masterKey0,format=raw,file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
> -machine pc-q35-5.0,accel=kvm,usb=off,dump-guest-core=off \
> --cpu Skylake-Client-IBRS,ss=on,vmx=on,hypervisor=on,tsc-adjust=on,clflushopt=on,umip=on,md-clear=on,stibp=on,arch-capabilities=on,ssbd=on,xsaves=on,pdpe1gb=on,skip-l1dfl-vmentry=on,pschange-mc-no=on \
> +-cpu Skylake-Client-IBRS,ss=on,vmx=on,hypervisor=on,tsc_adjust=on,clflushopt=on,umip=on,md-clear=on,stibp=on,arch-capabilities=on,ssbd=on,xsaves=on,pdpe1gb=on,skip-l1dfl-vmentry=on,pschange-mc-no=on \
... which should not have been impacted. Specifically the changed thing
it the above commandline is
(it's rather hard to spot):
tsc-adjust -> tsc_adjust
