From c3e0dbd7f780a58c4695f1cd8fc8afde80376737 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= <clg@kaod.org>
Date: Wed, 14 Aug 2019 17:47:52 +0200
Subject: [PATCH] powerpc/xmon: Check for HV mode when dumping XIVE info from
 OPAL
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References: bsc#1142019
Patch-mainline: v5.4-rc1
Git-commit: c3e0dbd7f780a58c4695f1cd8fc8afde80376737

Currently, the xmon 'dx' command calls OPAL to dump the XIVE state in
the OPAL logs and also outputs some of the fields of the internal XIVE
structures in Linux. The OPAL calls can only be done on baremetal
(PowerNV) and they crash a pseries machine. Fix by checking the
hypervisor feature of the CPU.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190814154754.23682-2-clg@kaod.org
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 arch/powerpc/xmon/xmon.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 14e56c25879f..25d4adccf750 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2534,13 +2534,16 @@ static void dump_pacas(void)
 static void dump_one_xive(int cpu)
 {
 	unsigned int hwid = get_hard_smp_processor_id(cpu);
-
-	opal_xive_dump(XIVE_DUMP_TM_HYP, hwid);
-	opal_xive_dump(XIVE_DUMP_TM_POOL, hwid);
-	opal_xive_dump(XIVE_DUMP_TM_OS, hwid);
-	opal_xive_dump(XIVE_DUMP_TM_USER, hwid);
-	opal_xive_dump(XIVE_DUMP_VP, hwid);
-	opal_xive_dump(XIVE_DUMP_EMU_STATE, hwid);
+	bool hv = cpu_has_feature(CPU_FTR_HVMODE);
+
+	if (hv) {
+		opal_xive_dump(XIVE_DUMP_TM_HYP, hwid);
+		opal_xive_dump(XIVE_DUMP_TM_POOL, hwid);
+		opal_xive_dump(XIVE_DUMP_TM_OS, hwid);
+		opal_xive_dump(XIVE_DUMP_TM_USER, hwid);
+		opal_xive_dump(XIVE_DUMP_VP, hwid);
+		opal_xive_dump(XIVE_DUMP_EMU_STATE, hwid);
+	}
 
 	if (setjmp(bus_error_jmp) != 0) {
 		catch_memory_errors = 0;
-- 
2.22.0