[PATCH v7 55/72] x86/sev-es: Handle RDPMC Events

Joerg Roedel
2020-09-07T13:15:56Z

From: Tom Lendacky <thomas.lendacky at amd.com>

Implement a handler for #VC exceptions caused by RDPMC instructions.

Signed-off-by: Tom Lendacky <thomas.lendacky at amd.com>
[ jroedel at suse.de: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel <jroedel at suse.de>
Signed-off-by: Joerg Roedel <jroedel at suse.de>
---
 arch/x86/kernel/sev-es.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 5c155f307129..2ee600f3184b 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -853,6 +853,25 @@ static enum es_result vc_handle_wbinvd(struct ghcb *ghcb,
 	return sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_WBINVD, 0, 0);
 }

+static enum es_result vc_handle_rdpmc(struct ghcb *ghcb, struct es_em_ctxt
*ctxt)
+{
+	enum es_result ret;
+
+	ghcb_set_rcx(ghcb, ctxt->regs->cx);
+
+	ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_RDPMC, 0, 0);
+	if (ret != ES_OK)
+		return ret;
+
+	if (!(ghcb_rax_is_valid(ghcb) && ghcb_rdx_is_valid(ghcb)))
+		return ES_VMM_ERROR;
+
+	ctxt->regs->ax = ghcb->save.rax;
+	ctxt->regs->dx = ghcb->save.rdx;
+
+	return ES_OK;
+}
+
 static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
 					 struct ghcb *ghcb,
 					 unsigned long exit_code)
@@ -870,6 +889,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt
*ctxt,
 	case SVM_EXIT_RDTSCP:
 		result = vc_handle_rdtsc(ghcb, ctxt, exit_code);
 		break;
+	case SVM_EXIT_RDPMC:
+		result = vc_handle_rdpmc(ghcb, ctxt);
+		break;
 	case SVM_EXIT_CPUID:
 		result = vc_handle_cpuid(ghcb, ctxt);
 		break;
--
2.28.0