On 4/5/2022 8:58 PM, Paolo Bonzini wrote:
On 3/4/22 20:48, isaku.yamahata@xxxxxxxxx wrote:
+ td_params->attributes = init_vm->attributes;
+ if (td_params->attributes & TDX_TD_ATTRIBUTE_PERFMON) {
+ pr_warn("TD doesn't support perfmon. KVM needs to save/restore "
+ "host perf registers properly.\n");
+ return -EOPNOTSUPP;
+ }
Why does KVM have to hardcode this (and LBR/AMX below)? Is the level of
hardware support available from tdx_caps, for example through the CPUID
configs (0xA for this one, 0xD for LBR and AMX)?
It's wrong code. PMU is allowed.
AMX and LBR are disallowed because and the time we wrote the codes they
are not supported by KVM. Now AMX should be allowed, but (arch-)LBR
should be still blocked until KVM merges arch-LBR support.
+ /* PT can be exposed to TD guest regardless of KVM's XSS support */
+ guest_supported_xss &= (supported_xss | XFEATURE_MASK_PT);
+ td_params->xfam = guest_supported_xcr0 | guest_supported_xss;
+ if (td_params->xfam & TDX_TD_XFAM_LBR) {
+ pr_warn("TD doesn't support LBR. KVM needs to save/restore "
+ "IA32_LBR_DEPTH properly.\n");
+ return -EOPNOTSUPP;
+ }
+
+ if (td_params->xfam & TDX_TD_XFAM_AMX) {
+ pr_warn("TD doesn't support AMX. KVM needs to save/restore "
+ "IA32_XFD, IA32_XFD_ERR properly.\n");
+ return -EOPNOTSUPP;
+ }
+ if (init_vm->tsc_khz)
+ guest_tsc_khz = init_vm->tsc_khz;
+ else
+ guest_tsc_khz = max_tsc_khz;
You can just use kvm->arch.default_tsc_khz in the latest kvm/queue.
yes. will change it.
