vl: warn for unavailable accelerators, clarify messages

So far, specifying an accelerator that was not compiled in did not result
in an error; fix that.

While at it, clarify the mysterious "Back to TCG" message.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/vl.c b/vl.c
index 0f620be8b1..c350eef046 100644
--- a/vl.c
+++ b/vl.c
@@ -2723,6 +2723,8 @@ static int do_configure_accelerator(void *opaque, QemuOpts *opts, Error **errp)
     int ret;
 
     if (!ac) {
+        *p_init_failed = true;
+        error_report("invalid accelerator %s", acc);
         return 0;
     }
     ret = accel_init_machine(ac, current_machine);
@@ -2777,6 +2779,9 @@ static void configure_accelerators(const char *progname)
              */
             if (accel_find(*tmp)) {
                 qemu_opts_parse_noisily(qemu_find_opts("accel"), *tmp, true);
+            } else {
+                init_failed = true;
+                error_report("invalid accelerator %s", *tmp);
             }
         }
     } else {
@@ -2796,7 +2801,7 @@ static void configure_accelerators(const char *progname)
 
     if (init_failed) {
         AccelClass *ac = ACCEL_GET_CLASS(current_machine->accelerator);
-        error_report("Back to %s accelerator", ac->name);
+        error_report("falling back to %s", ac->name);
     }
 
     if (use_icount && !(tcg_enabled() || qtest_enabled())) {