[PATCH 53/70] x86/sev-es: Handle RDPMC Events

From: Joerg Roedel
Date: Thu Mar 19 2020 - 05:15:04 EST


From: Tom Lendacky <thomas.lendacky@xxxxxxx>

Implement a handler for #VC exceptions caused by RDPMC 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 | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index afbe574126f3..ec11088497a4 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -682,6 +682,25 @@ static enum es_result vc_handle_rdtsc(struct ghcb *ghcb, struct es_em_ctxt *ctxt
return ES_OK;
}

+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_is_valid_rax(ghcb) && ghcb_is_valid_rdx(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,
@@ -699,6 +718,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt,
case SVM_EXIT_RDTSC:
result = vc_handle_rdtsc(ghcb, ctxt);
break;
+ case SVM_EXIT_RDPMC:
+ result = vc_handle_rdpmc(ghcb, ctxt);
+ break;
case SVM_EXIT_CPUID:
result = vc_handle_cpuid(ghcb, ctxt);
break;
--
2.17.1