diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 076cc7f..559cb16 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3670,6 +3670,9 @@
 
 	switch (p->cmd) {
 	case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
+		if (root->fs_info->sb->s_flags & MS_RDONLY)
+			return -EROFS;
+
 		if (atomic_xchg(
 			&root->fs_info->mutually_exclusive_operation_running,
 			1)) {