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From 779370f8d1cf47e46b39b210a43d24804e551071 Mon Sep 17 00:00:00 2001
From: Laurent Vivier <lvivier@redhat.com>
Date: Mon, 12 Feb 2018 12:04:49 +0100
Subject: [PATCH 04/15] spapr: set vsmt to MAX(8, smp_threads)

RH-Author: Laurent Vivier <lvivier@redhat.com>
Message-id: <20180212120449.20810-1-lvivier@redhat.com>
Patchwork-id: 78978
O-Subject: [RHV7.5 qemu-kvm-rhev PATCH] spapr: set vsmt to MAX(8, smp_threads)
Bugzilla: 1542421
RH-Acked-by: David Gibson <dgibson@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Serhii Popovych <spopovyc@redhat.com>

We ignore silently the value of smp_threads when we set
the default VSMT value, and if smp_threads is greater than VSMT
kernel is going into trouble later.

Fixes: 8904e5a750
("spapr: Adjust default VSMT value for better migration compatibility")

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
(cherry picked from commit 4ad64cbd0c3f9df15be5f7d1c920285551e802ca)
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/ppc/spapr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 6c4c088..2b991d8 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -2261,7 +2261,7 @@ static void spapr_set_vsmt_mode(sPAPRMachineState *spapr, Error **errp)
          * the value that we'd get with KVM on POWER8, the
          * overwhelmingly common case in production systems.
          */
-        spapr->vsmt = 8;
+        spapr->vsmt = MAX(8, smp_threads);
     }
 
     /* KVM: If necessary, set the SMT mode: */
-- 
1.8.3.1