From: Joerg Roedel <jroedel@suse.de>
Date: Fri, 12 Mar 2021 13:38:24 +0100
Subject: x86/sev-es: Replace open-coded hlt-loops with sev_es_terminate()
Git-commit: f15a0a732aefb46f999c2a8aa8f9f16e71cec5b2
Patch-mainline: v5.13-rc1
References: jsc#SLE-14337

There are a few places left in the SEV-ES C code where hlt loops and/or
terminate requests are implemented. Replace them all with calls to
sev_es_terminate().

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210312123824.306-9-joro@8bytes.org
---
 arch/x86/boot/compressed/sev-es.c |   12 +++---------
 arch/x86/kernel/sev-es-shared.c   |   10 +++-------
 2 files changed, 6 insertions(+), 16 deletions(-)

--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -200,14 +200,8 @@ void do_boot_stage2_vc(struct pt_regs *r
 	}
 
 finish:
-	if (result == ES_OK) {
+	if (result == ES_OK)
 		vc_finish_insn(&ctxt);
-	} else if (result != ES_RETRY) {
-		/*
-		 * For now, just halt the machine. That makes debugging easier,
-		 * later we just call sev_es_terminate() here.
-		 */
-		while (true)
-			asm volatile("hlt\n");
-	}
+	else if (result != ES_RETRY)
+		sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
 }
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -24,7 +24,7 @@ static bool __init sev_es_check_cpu_feat
 	return true;
 }
 
-static void sev_es_terminate(unsigned int reason)
+static void __noreturn sev_es_terminate(unsigned int reason)
 {
 	u64 val = GHCB_SEV_TERMINATE;
 
@@ -206,12 +206,8 @@ void __init do_vc_no_ghcb(struct pt_regs
 	return;
 
 fail:
-	sev_es_wr_ghcb_msr(GHCB_SEV_TERMINATE);
-	VMGEXIT();
-
-	/* Shouldn't get here - if we do halt the machine */
-	while (true)
-		asm volatile("hlt\n");
+	/* Terminate the guest */
+	sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
 }
 
 static enum es_result vc_insn_string_read(struct es_em_ctxt *ctxt,