memory: Return -1 again on reads from unsigned regions

This restore the behavior prior to b018ddf633 which accidentally changed
the return code to 0. Specifically guests probing for register existence
were affected by this.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/memory.c b/memory.c
index 9938b6ba458e6e3caeb18d64b9fac2c64bc04c34..34a088e90f4cb745e6fd462c6fc9b14bc6b25f41 100644 (file)
--- a/memory.c
+++ b/memory.c
@@ -840,7 +840,7 @@ static uint64_t unassigned_mem_read(void *opaque, hwaddr addr,
     if (current_cpu != NULL) {
         cpu_unassigned_access(current_cpu, addr, false, false, 0, size);
     }
-    return 0;
+    return -1ULL;
 }
 
 static void unassigned_mem_write(void *opaque, hwaddr addr,