Don't crash if KVM is busy

Return an error when kvm_ioctl(KVM_CREATE_VM) fails, so we stop
with an error message instead of a segmentation fault.

Change-Id: Ie8f7efca6d50e096bd5f1c05bc91c53a9770b73c

1 files changed, 5 insertions, 2 deletions

diff --git a/kvm-all.c b/kvm-all.c
index 0930d33..2865b2f 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -427,8 +427,8 @@ int kvm_init(int smp_cpus)
     s->vmfd = -1;
     s->fd = open("/dev/kvm", O_RDWR);
     if (s->fd == -1) {
-        fprintf(stderr, "Could not access KVM kernel module: %m\n");
         ret = -errno;
+        fprintf(stderr, "Could not access KVM kernel module: %m\n");
         goto err;
     }
 
@@ -447,8 +447,11 @@ int kvm_init(int smp_cpus)
     }
 
     s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
-    if (s->vmfd < 0)
+    if (s->vmfd < 0) {
+        ret = -errno;
+        fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %s\n", strerror(errno));
         goto err;
+    }
 
     /* initially, KVM allocated its own memory and we had to jump through
      * hooks to make phys_ram_base point to this.  Modern versions of KVM