diff --git a/bootloader_message/bootloader_message.cpp b/bootloader_message/bootloader_message.cpp
index 62d8c67..59c2b2e 100644
--- a/bootloader_message/bootloader_message.cpp
+++ b/bootloader_message/bootloader_message.cpp
@@ -88,7 +88,7 @@
   if (!wait_for_device(misc_blk_device, err)) {
     return false;
   }
-  android::base::unique_fd fd(open(misc_blk_device.c_str(), O_WRONLY | O_SYNC));
+  android::base::unique_fd fd(open(misc_blk_device.c_str(), O_RDONLY));
   if (fd.get() == -1) {
     *err = android::base::StringPrintf("failed to open %s: %s", misc_blk_device.c_str(),
                                        strerror(errno));