--- a/sys/dev/disk/amd/amd.c
+++ b/sys/dev/disk/amd/amd.c
@@ -1432,7 +1432,9 @@
 			}
 			break;
 		} else {
-			panic("amdsentmsg: Inconsistent msg buffer");
+			/* Unrecognized byte in our own msgout buffer:
+			 * bail out instead of panicking. */
+			break;
 		}
 	}
 	return (found);