From 53a19a9a5f9811a911e9b69ef36afb0d66b5d85c Mon Sep 17 00:00:00 2001
From: David Hildenbrand <david@redhat.com>
Date: Mon, 8 Oct 2018 17:32:04 +0200
Subject: [PATCH] s390x/tcg: always enable AFP for linux-user
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linux-user should always enable AFP, otherwise our emulated binary
might crash once it tries to make use of additional floating-point
registers or instructions.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Alex Bennée <alex.bennee@linaro.org>
Fixes: db0504154e ("s390x/tcg: check for AFP-register, BFP and DFP data exceptions")
Reported-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tested-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/s390x/cpu.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c
index 8ed4823d6e..18ba7f85a5 100644
--- a/target/s390x/cpu.c
+++ b/target/s390x/cpu.c
@@ -145,6 +145,11 @@ static void s390_cpu_full_reset(CPUState *s)
     env->cregs[0] = CR0_RESET;
     env->cregs[14] = CR14_RESET;
 
+#if defined(CONFIG_USER_ONLY)
+    /* user mode should always be allowed to use the full FPU */
+    env->cregs[0] |= CR0_AFP;
+#endif
+
     /* architectured initial value for Breaking-Event-Address register */
     env->gbea = 1;