kvm: ppc: detect old headers

When compiling Qemu with older kernel headers, the PVR setting
mechanism isn't available yet. Unfortunately, back then I didn't add
a capability we could check against, so all we can do is add a configure
test to see if we support PVR setting. For BookE, we don't care yet.

This fixes compilation errors with KVM enabled on older kernel headers
(like 2.6.32).

Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 18 insertions, 0 deletions

diff --git a/configure b/configure
index fbf5d5f67c..adfbb40946 100755
--- a/configure
+++ b/configure
@@ -1772,6 +1772,21 @@ recent kvm-kmod from http://sourceforge.net/projects/kvm."
 fi
 
 ##########################################
+# test for ppc kvm pvr setting
+
+if test "$kvm" = "yes" && test "$cpu" = "ppc" -o "$cpu" = "ppc64"; then
+            cat > $TMPC <<EOF
+    #include <asm/kvm.h>
+    int main(void) { struct kvm_sregs s; s.pvr = 0; return 0; }
+EOF
+    if compile_prog "$kvm_cflags" "" ; then
+        kvm_ppc_pvr=yes
+    else
+        kvm_ppc_pvr=no
+    fi
+fi
+
+##########################################
 # test for vhost net
 
 if test "$vhost_net" != "no"; then
@@ -3257,6 +3272,9 @@ case "$target_arch2" in
       if test $vhost_net = "yes" ; then
         echo "CONFIG_VHOST_NET=y" >> $config_target_mak
       fi
+      if test $kvm_ppc_pvr = "yes" ; then
+        echo "CONFIG_KVM_PPC_PVR=y" >> $config_target_mak
+      fi
     fi
 esac
 if test "$target_bigendian" = "yes" ; then