From cb43b40e88fde117852a7a52506e4421d82c4fc8 Mon Sep 17 00:00:00 2001
From: Suraj Jitindar Singh <sursingh@redhat.com>
Date: Tue, 13 Mar 2018 05:21:30 +0100
Subject: [PATCH 08/17] ppc/spapr-caps: Disallow setting workaround for
 spapr-cap-ibs

RH-Author: Suraj Jitindar Singh <sursingh@redhat.com>
Message-id: <1520918499-27663-3-git-send-email-sursingh@redhat.com>
Patchwork-id: 79252
O-Subject: [RHEL7.5 qemu-kvm-rhev PATCH 02/11] ppc/spapr-caps: Disallow setting workaround for spapr-cap-ibs
Bugzilla: 1554957
RH-Acked-by: David Gibson <dgibson@redhat.com>
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

The spapr-cap cap-ibs can only have values broken or fixed as there is
no explicit workaround required. Currently setting the value workaround
for this cap will hit an assert if the guest makes the hcall
h_get_cpu_characteristics.

Report an error when attempting to apply the setting with a more helpful
error message.

Reported-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
(cherry picked from commit 4f5b039d2bf9bb26b6e26a3dc65da36fe970cba9)

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1548919

Signed-off-by: Suraj Jitindar Singh <sursingh@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/ppc/spapr_caps.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c
index e69d308..99a4b71 100644
--- a/hw/ppc/spapr_caps.c
+++ b/hw/ppc/spapr_caps.c
@@ -205,7 +205,9 @@ static void cap_safe_bounds_check_apply(sPAPRMachineState *spapr, uint8_t val,
 static void cap_safe_indirect_branch_apply(sPAPRMachineState *spapr,
                                            uint8_t val, Error **errp)
 {
-    if (tcg_enabled() && val) {
+    if (val == SPAPR_CAP_WORKAROUND) { /* Can only be Broken or Fixed */
+        error_setg(errp, "Requested safe indirect branch capability level \"workaround\" not valid, try cap-ibs=fixed");
+    } else if (tcg_enabled() && val) {
         /* TODO - for now only allow broken for TCG */
         error_setg(errp, "Requested safe indirect branch capability level not supported by tcg, try a different value for cap-ibs");
     } else if (kvm_enabled() && (val > kvmppc_get_cap_safe_indirect_branch())) {
@@ -263,7 +265,7 @@ sPAPRCapabilityInfo capability_table[SPAPR_CAP_NUM] = {
     },
     [SPAPR_CAP_IBS] = {
         .name = "ibs",
-        .description = "Indirect Branch Serialisation" VALUE_DESC_TRISTATE,
+        .description = "Indirect Branch Serialisation (broken, fixed)",
         .index = SPAPR_CAP_IBS,
         .get = spapr_cap_get_tristate,
         .set = spapr_cap_set_tristate,
-- 
1.8.3.1