diff --git a/meta/classes-recipe/testimage.bbclass b/meta/classes-recipe/testimage.bbclass
index 8d2fab21df..819c7d2bf4 100644
--- a/meta/classes-recipe/testimage.bbclass
+++ b/meta/classes-recipe/testimage.bbclass
@@ -189,11 +189,7 @@ def get_testimage_boot_patterns(d):
                     search_login_succeeded,search_cmd_finished\n Make sure your TESTIMAGE_BOOT_PATTERNS=%s \
                     contains an accepted flag.' % d.getVar('TESTIMAGE_BOOT_PATTERNS'))
                     return
-                # We know boot prompt is searched through in binary format, others might be expressions
-                if flag == 'search_reached_prompt':
-                    boot_patterns[flag] = flagval.encode()
-                else:
-                    boot_patterns[flag] = flagval.encode().decode('unicode-escape')
+                boot_patterns[flag] = flagval.encode().decode('unicode-escape')
     return boot_patterns
 
 
diff --git a/meta/lib/oeqa/utils/qemurunner.py b/meta/lib/oeqa/utils/qemurunner.py
index 948f8adc9f..6a85f57e49 100644
--- a/meta/lib/oeqa/utils/qemurunner.py
+++ b/meta/lib/oeqa/utils/qemurunner.py
@@ -85,7 +85,7 @@ class QemuRunner:
         accepted_patterns = ['search_reached_prompt', 'send_login_user', 'search_login_succeeded', 'search_cmd_finished']
         default_boot_patterns = defaultdict(str)
         # Default to the usual paterns used to communicate with the target
-        default_boot_patterns['search_reached_prompt'] = b' login:'
+        default_boot_patterns['search_reached_prompt'] = ' login:'
         default_boot_patterns['send_login_user'] = 'root\n'
         default_boot_patterns['search_login_succeeded'] = r"root@[a-zA-Z0-9\-]+:~#"
         default_boot_patterns['search_cmd_finished'] = r"[a-zA-Z0-9]+@[a-zA-Z0-9\-]+:~#"
@@ -109,12 +109,15 @@ class QemuRunner:
             sock.close()
             raise
 
+    def decode_qemulog(self, todecode):
+        # Sanitize the data received from qemu as it may contain control characters
+        msg = todecode.decode("utf-8", errors='ignore')
+        msg = re_control_char.sub('', msg)
+        return msg
+
     def log(self, msg):
         if self.logfile:
-            # It is needed to sanitize the data received from qemu
-            # because is possible to have control characters
-            msg = msg.decode("utf-8", errors='ignore')
-            msg = re_control_char.sub('', msg)
+            msg = self.decode_qemulog(msg)
             self.msg += msg
             with codecs.open(self.logfile, "a", encoding="utf-8") as f:
                 f.write("%s" % msg)
@@ -468,7 +471,9 @@ class QemuRunner:
                             self.log(data)
 
                         data = b''
-                        if self.boot_patterns['search_reached_prompt'] in bootlog:
+
+                        decodedlog = self.decode_qemulog(bootlog)
+                        if self.boot_patterns['search_reached_prompt'] in decodedlog:
                             self.server_socket = qemusock
                             stopread = True
                             reachedlogin = True
@@ -488,10 +493,10 @@ class QemuRunner:
                 self.logger.warning("Target didn't reach login banner in %d seconds (%s)" %
                                   (self.boottime, time.strftime("%D %H:%M:%S")))
             tail = lambda l: "\n".join(l.splitlines()[-25:])
-            bootlog = bootlog.decode("utf-8")
+            bootlog = self.decode_qemulog(bootlog)
             # in case bootlog is empty, use tail qemu log store at self.msg
             lines = tail(bootlog if bootlog else self.msg)
-            self.logger.warning("Last 25 lines of text:\n%s" % lines)
+            self.logger.warning("Last 25 lines of text (%d):\n%s" % (len(bootlog), lines))
             self.logger.warning("Check full boot log: %s" % self.logfile)
             self._dump_host()
             self.stop()