Comment 10 for bug 1828495

I just realized that from my previous comment I said:

(2)

There is *no current request* to allow following features to be
reported by EAX_7H_ECX_0_EDX QEMU/KVM right now:

* CPUID.(EAX=7H,ECX=0):EDX[27] STIBP support flag.
* CPUID.(EAX=7H,ECX=0):EDX[28] L1D_FLUSH support flag.
* CPUID.(EAX=7H,ECX=0):EDX[31] SSBD support flag.

But the other bug:

https://bugs.launchpad.net/intel/+bug/1830821

Is about enabling SSBD support:

CPUID.(EAX=7H,ECX=0):EDX[29] (IA32_ARCH_CAPABILITIES feature flag)
...
- (bit 4) SSB_NO: processor not susceptible to spec store bypass

and to enable guest to opt out from SSB (speculative store bypass)