fix SIGSEGV when USE_KQEMU is defined

Signed-off-by: Alex Ivanov <void@aleksoft.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6674 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/block.c b/block.c
index 4f4bf7c..c214ff3 100644
--- a/block.c
+++ b/block.c
@@ -1263,7 +1263,7 @@
     if (!s->is_write) {
         qemu_iovec_from_buffer(s->iov, s->bounce, s->iov->size);
     }
-    qemu_free(s->bounce);
+    qemu_vfree(s->bounce);
     s->this_aiocb->cb(s->this_aiocb->opaque, ret);
     qemu_aio_release(s->this_aiocb);
 }