diff --git a/docs/devel/migration/main.rst b/docs/devel/migration/main.rst
index 8024275d6d..54385a23e5 100644
--- a/docs/devel/migration/main.rst
+++ b/docs/devel/migration/main.rst
@@ -44,7 +44,8 @@ over any transport.
 - file migration: do the migration using a file that is passed to QEMU
   by path. A file offset option is supported to allow a management
   application to add its own metadata to the start of the file without
-  QEMU interference.
+  QEMU interference. Note that QEMU does not flush cached file
+  data/metadata at the end of migration.
 
 In addition, support is included for migration using RDMA, which
 transports the page data using ``RDMA``, where the hardware takes care of
diff --git a/io/channel-file.c b/io/channel-file.c
index d4706fa592..a6ad7770c6 100644
--- a/io/channel-file.c
+++ b/io/channel-file.c
@@ -242,11 +242,6 @@ static int qio_channel_file_close(QIOChannel *ioc,
 {
     QIOChannelFile *fioc = QIO_CHANNEL_FILE(ioc);
 
-    if (qemu_fdatasync(fioc->fd) < 0) {
-        error_setg_errno(errp, errno,
-                         "Unable to synchronize file data with storage device");
-        return -1;
-    }
     if (qemu_close(fioc->fd) < 0) {
         error_setg_errno(errp, errno,
                          "Unable to close file");
diff --git a/migration/multifd.c b/migration/multifd.c
index d4a44da559..bf9d483f7a 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -710,16 +710,26 @@ static bool multifd_send_cleanup_channel(MultiFDSendParams *p, Error **errp)
     if (p->c) {
         migration_ioc_unregister_yank(p->c);
         /*
-         * An explicit close() on the channel here is normally not
-         * required, but can be helpful for "file:" iochannels, where it
-         * will include fdatasync() to make sure the data is flushed to the
-         * disk backend.
+         * The object_unref() cannot guarantee the fd will always be
+         * released because finalize() of the iochannel is only
+         * triggered on the last reference and it's not guaranteed
+         * that we always hold the last refcount when reaching here.
          *
-         * The object_unref() cannot guarantee that because: (1) finalize()
-         * of the iochannel is only triggered on the last reference, and
-         * it's not guaranteed that we always hold the last refcount when
-         * reaching here, and, (2) even if finalize() is invoked, it only
-         * does a close(fd) without data flush.
+         * Closing the fd explicitly has the benefit that if there is any
+         * registered I/O handler callbacks on such fd, that will get a
+         * POLLNVAL event and will further trigger the cleanup to finally
+         * release the IOC.
+         *
+         * FIXME: It should logically be guaranteed that all multifd
+         * channels have no I/O handler callback registered when reaching
+         * here, because migration thread will wait for all multifd channel
+         * establishments to complete during setup.  Since
+         * migrate_fd_cleanup() will be scheduled in main thread too, all
+         * previous callbacks should guarantee to be completed when
+         * reaching here.  See multifd_send_state.channels_created and its
+         * usage.  In the future, we could replace this with an assert
+         * making sure we're the last reference, or simply drop it if above
+         * is more clear to be justified.
          */
         qio_channel_close(p->c, &error_abort);
         object_unref(OBJECT(p->c));