diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index 730c009dea2ce9467b119080d7b8bf075cb72702..ced4c940008b080923c0345e9afc8682a5814f4d 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -233,7 +233,7 @@ int spi_flash_cmd_erase(struct spi_flash *flash, u8 erase_cmd,
 			goto out;
 	}
 
-	debug("SF: Successfully erased %lu bytes @ %#x\n",
+	debug("SF: Successfully erased %zu bytes @ %#x\n",
 	      len * erase_size, start);
 
  out: