OvmfPkg/AmdSvsmLib: Add support for the SVSM create/delete vCPU calls
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4654
The RMPADJUST instruction is used to alter the VMSA attribute of a page,
but the VMSA attribute can only be changed when running at VMPL0. When
an SVSM is present, use the SVSM_CORE_CREATE_VCPU and SVSM_CORE_DELTE_VCPU
calls to add or remove the VMSA attribute on a page instead of issuing
the RMPADJUST instruction directly.
Implement the AmdSvsmSnpVmsaRmpAdjust() API to perform the proper operation
to update the VMSA attribute.
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
diff --git a/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c b/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c
index fb3fda7..6c79ee7 100644
--- a/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c
+++ b/OvmfPkg/Library/AmdSvsmLib/AmdSvsmLib.c
@@ -378,6 +378,57 @@
}
/**
+ Perform an RMPADJUST operation to alter the VMSA setting of a page.
+
+ Add or remove the VMSA attribute for a page.
+
+ @param[in] Vmsa Pointer to an SEV-ES save area page
+ @param[in] ApicId APIC ID associated with the VMSA
+ @param[in] SetVmsa Boolean indicator as to whether to set or
+ or clear the VMSA setting for the page
+
+ @retval EFI_SUCCESS RMPADJUST operation successful
+ @retval EFI_UNSUPPORTED Operation is not supported
+ @retval EFI_INVALID_PARAMETER RMPADJUST operation failed, an invalid
+ parameter was supplied
+
+**/
+STATIC
+EFI_STATUS
+SvsmVmsaRmpAdjust (
+ IN SEV_ES_SAVE_AREA *Vmsa,
+ IN UINT32 ApicId,
+ IN BOOLEAN SetVmsa
+ )
+{
+ SVSM_CALL_DATA SvsmCallData;
+ SVSM_FUNCTION Function;
+ UINTN Ret;
+
+ SvsmCallData.Caa = (SVSM_CAA *)AmdSvsmSnpGetCaa ();
+
+ Function.Id.Protocol = 0;
+
+ if (SetVmsa) {
+ Function.Id.CallId = 2;
+
+ SvsmCallData.RaxIn = Function.Uint64;
+ SvsmCallData.RcxIn = (UINT64)(UINTN)Vmsa;
+ SvsmCallData.RdxIn = (UINT64)(UINTN)Vmsa + SIZE_4KB;
+ SvsmCallData.R8In = ApicId;
+ } else {
+ Function.Id.CallId = 3;
+
+ SvsmCallData.RaxIn = Function.Uint64;
+ SvsmCallData.RcxIn = (UINT64)(UINTN)Vmsa;
+ }
+
+ Ret = SvsmMsrProtocol (&SvsmCallData);
+
+ return (Ret == 0) ? EFI_SUCCESS : EFI_INVALID_PARAMETER;
+}
+
+/**
Perform a native RMPADJUST operation to alter the VMSA setting of a page.
Add or remove the VMSA attribute for a page.
@@ -444,5 +495,6 @@
IN BOOLEAN SetVmsa
)
{
- return BaseVmsaRmpAdjust (Vmsa, SetVmsa);
+ return AmdSvsmIsSvsmPresent () ? SvsmVmsaRmpAdjust (Vmsa, ApicId, SetVmsa)
+ : BaseVmsaRmpAdjust (Vmsa, SetVmsa);
}
