diff --git a/fs/file_table.c b/fs/file_table.c
index b98404b54383..32d12b78bac8 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -393,7 +393,9 @@ retry:
 			continue;
 		if (!(f->f_mode & FMODE_WRITE))
 			continue;
+		spin_lock(&f->f_lock);
 		f->f_mode &= ~FMODE_WRITE;
+		spin_unlock(&f->f_lock);
 		if (file_check_writeable(f) != 0)
 			continue;
 		file_release_write(f);
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index f19ed866c95f..fcafe6087f69 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1998,7 +1998,9 @@ nfs4_file_downgrade(struct file *filp, unsigned int share_access)
 {
 	if (share_access & NFS4_SHARE_ACCESS_WRITE) {
 		drop_file_write_access(filp);
+		spin_lock(&filp->f_lock);
 		filp->f_mode = (filp->f_mode | FMODE_READ) & ~FMODE_WRITE;
+		spin_unlock(&filp->f_lock);
 	}
 }