[Qemu-devel] [PATCH for-2.13 09/10] target/ppc: Don't bother with MSR_EP in cpu_ppc_set_papr()

[David Gibson <david@gibson.dropbear.id.au>]

cpu_ppc_set_papr() removes the EP and HV bits from the MSR mask.  While
removing the HV bit makes sense (a cpu in PAPR mode should never be
emulated in hypervisor mode), the EP bit is just bizarre.  Although it's
true that a papr mode guest shouldn't be able to change the exception
prefix, the MSR[EP] bit doesn't even exist on the cpus supported for PAPR
mode, so it's pointless to do anything with it here.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 target/ppc/translate_init.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/target/ppc/translate_init.c b/target/ppc/translate_init.c
index 5e89901149..bb5559d799 100644
--- a/target/ppc/translate_init.c
+++ b/target/ppc/translate_init.c
@@ -8870,12 +8870,11 @@ void cpu_ppc_set_papr(PowerPCCPU *cpu, PPCVirtualHypervisor *vhyp)
 
     cpu->vhyp = vhyp;
 
-    /* PAPR always has exception vectors in RAM not ROM. To ensure this,
-     * MSR[IP] should never be set.
-     *
-     * We also disallow setting of MSR_HV
+    /*
+     * With a virtual hypervisor mode we never allow the CPU to go
+     * hypervisor mode itself
      */
-    env->msr_mask &= ~((1ull << MSR_EP) | MSR_HVB);
+    env->msr_mask &= ~MSR_HVB;
 
     /* Tell KVM that we're in PAPR mode */
     if (kvm_enabled()) {
-- 
2.14.3