From 4d5b8f8fecbbf460f8c2f789784542e2d0e1fd20 Mon Sep 17 00:00:00 2001
From: David Gibson <dgibson@redhat.com>
Date: Fri, 12 Jan 2018 03:43:33 +0100
Subject: [PATCH 06/12] spapr: Correct compatibility mode setting for
 hotplugged CPUs

RH-Author: David Gibson <dgibson@redhat.com>
Message-id: <20180112034333.5242-1-dgibson@redhat.com>
Patchwork-id: 78556
O-Subject: [RHEL-7.5 qemu-kvm-rhev PATCH] spapr: Correct compatibility mode setting for hotplugged CPUs
Bugzilla: 1528234
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Serhii Popovych <spopovyc@redhat.com>

From: David Gibson <david@gibson.dropbear.id.au>

Currently the pseries machine sets the compatibility mode for the
guest's cpus in two places: 1) at machine reset and 2) after CAS
negotiation.

This means that if we set or negotiate a compatiblity mode, then
hotplug a cpu, the hotplugged cpu doesn't get the right mode set and
will incorrectly have the full native features.

To correct this, we set the compatibility mode on a cpu when it is
brought online with the 'start-cpu' RTAS call.  Given that we no
longer need to set the compatibility mode on all CPUs at machine
reset, so we change that to only set the mode for the boot cpu.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reported-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
(cherry picked from commit 51f84465dd985fc21589b2eac1f18658fc9783e9)
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

Conflicts:
	hw/ppc/spapr_rtas.c

Minor contextual conflict.

Signed-off-by: David Gibson <dgibson@redhat.com>
---
 hw/ppc/spapr.c      | 2 +-
 hw/ppc/spapr_rtas.c | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index e276632..cdc56f3 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1462,7 +1462,7 @@ static void ppc_spapr_reset(void)
         spapr_ovec_cleanup(spapr->ov5_cas);
         spapr->ov5_cas = spapr_ovec_new();
 
-        ppc_set_compat_all(spapr->max_compat_pvr, &error_fatal);
+        ppc_set_compat(first_ppc_cpu, spapr->max_compat_pvr, &error_fatal);
     }
 
     fdt = spapr_build_fdt(spapr, rtas_addr, spapr->rtas_size);
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 94a2799..93f09a0 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -162,6 +162,7 @@ static void rtas_start_cpu(PowerPCCPU *cpu_, sPAPRMachineState *spapr,
     if (cpu != NULL) {
         CPUState *cs = CPU(cpu);
         CPUPPCState *env = &cpu->env;
+        Error *local_err = NULL;
 
         if (!cs->halted) {
             rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
@@ -173,6 +174,14 @@ static void rtas_start_cpu(PowerPCCPU *cpu_, sPAPRMachineState *spapr,
          * new cpu enters */
         kvm_cpu_synchronize_state(cs);
 
+        /* Set compatibility mode to match existing cpus */
+        ppc_set_compat(cpu, POWERPC_CPU(first_cpu)->compat_pvr, &local_err);
+        if (local_err) {
+            error_report_err(local_err);
+            rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
+            return;
+        }
+
         env->msr = (1ULL << MSR_SF) | (1ULL << MSR_ME);
         env->nip = start;
         env->gpr[3] = r3;
-- 
1.8.3.1