diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 57d8a16438a02324186cce165d768e637eaba63b..8c28eb0cbdac7392c3ed9d895e67aa81545b7613 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -567,7 +567,7 @@ static void __init early_cmdline_parse(void)
 	if ((long)_prom->chosen > 0)
 		l = prom_getprop(_prom->chosen, "bootargs", p, COMMAND_LINE_SIZE-1);
 #ifdef CONFIG_CMDLINE
-	if (l == 0) /* dbl check */
+	if (l <= 0 || p[0] == '\0') /* dbl check */
 		strlcpy(RELOC(prom_cmd_line),
 			RELOC(CONFIG_CMDLINE), sizeof(prom_cmd_line));
 #endif /* CONFIG_CMDLINE */