[PATCH 49/62] x86/sev-es: Handle MWAIT/MWAITX Events

[Joerg Roedel]

From: Tom Lendacky <thomas.lendacky@xxxxxxx>

Implement a handler for #VC exceptions caused by MWAIT and MWAITX
instructions.

Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
[ jroedel@xxxxxxx: Adapt to #VC handling infrastructure ]
Co-developed-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
 arch/x86/kernel/sev-es.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 865f510d11ba..8f1e84da6fa6 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -333,6 +333,14 @@ static enum es_result handle_monitor(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 	return ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MONITOR, 0, 0);
 }
 
+static enum es_result handle_mwait(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
+{
+	ghcb_set_rax(ghcb, ctxt->regs->ax);
+	ghcb_set_rcx(ghcb, ctxt->regs->cx);
+
+	return ghcb_hv_call(ghcb, ctxt, SVM_EXIT_MWAIT, 0, 0);
+}
+
 static enum es_result handle_vc_exception(struct es_em_ctxt *ctxt,
 					  struct ghcb *ghcb,
 					  unsigned long exit_code,
@@ -372,6 +380,9 @@ static enum es_result handle_vc_exception(struct es_em_ctxt *ctxt,
 	case SVM_EXIT_MONITOR:
 		result = handle_monitor(ghcb, ctxt);
 		break;
+	case SVM_EXIT_MWAIT:
+		result = handle_mwait(ghcb, ctxt);
+		break;
 	case SVM_EXIT_NPF:
 		result = handle_mmio(ghcb, ctxt);
 		break;
-- 
2.17.1