Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20150430' into staging

First pile of s390x patches for 2.4, including:
- some cleanup patches
- sort most of the s390x devices into categories
- support for the new STSI post handler, used to insert vm name and
  friends
- support for the new MEM_OP ioctl (including access register mode)
  for accessing guest memory

# gpg: Signature made Thu Apr 30 12:56:58 2015 BST using RSA key ID C6F02FAF
# gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"

* remotes/cohuck/tags/s390x-20150430:
  kvm: better advice for failed s390x startup
  s390x/kvm: Support access register mode for KVM_S390_MEM_OP ioctl
  s390x/mmu: Use ioctl for reading and writing from/to guest memory
  s390x/kvm: Put vm name, extended name and UUID into STSI322 SYSIB
  linux-headers: update
  s390x/mmu: Use access type definitions instead of magic values
  s390x/ipl: sort into categories
  sclp: sort into categories
  s390-virtio: sort into categories
  virtio-ccw: sort into categories

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 11 insertions, 2 deletions

diff --git a/kvm-all.c b/kvm-all.c
index 2a717e5b50..3f7061a180 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -1544,8 +1544,17 @@ static int kvm_init(MachineState *ms)
                 strerror(-ret));
 
 #ifdef TARGET_S390X
-        fprintf(stderr, "Please add the 'switch_amode' kernel parameter to "
-                        "your host kernel command line\n");
+        if (ret == -EINVAL) {
+            fprintf(stderr,
+                    "Host kernel setup problem detected. Please verify:\n");
+            fprintf(stderr, "- for kernels supporting the switch_amode or"
+                    " user_mode parameters, whether\n");
+            fprintf(stderr,
+                    "  user space is running in primary address space\n");
+            fprintf(stderr,
+                    "- for kernels supporting the vm.allocate_pgste sysctl, "
+                    "whether it is enabled\n");
+        }
 #endif
         goto err;
     }