diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b89b5d755ce0..be23059344b4 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4579,4 +4579,9 @@ static inline void f2fs_handle_page_eio(struct f2fs_sb_info *sbi, pgoff_t ofs,
 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
 #define EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */
 
+static inline bool f2fs_is_readonly(struct f2fs_sb_info *sbi)
+{
+	return !!f2fs_sb_has_readonly(sbi) || f2fs_readonly(sbi->sb);
+}
+
 #endif /* _LINUX_F2FS_H */
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 75027ff85cd9..baa8f0860192 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1353,12 +1353,16 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
 		return -EINVAL;
 	}
 
-	if ((f2fs_sb_has_readonly(sbi) || f2fs_readonly(sbi->sb)) &&
-		test_opt(sbi, FLUSH_MERGE)) {
+	if (f2fs_is_readonly(sbi) && test_opt(sbi, FLUSH_MERGE)) {
 		f2fs_err(sbi, "FLUSH_MERGE not compatible with readonly mode");
 		return -EINVAL;
 	}
 
+	if (f2fs_is_readonly(sbi) && test_opt(sbi, DISCARD)) {
+		f2fs_err(sbi, "DISCARD not compatible with readonly mode");
+		return -EINVAL;
+	}
+
 	if (f2fs_sb_has_readonly(sbi) && !f2fs_readonly(sbi->sb)) {
 		f2fs_err(sbi, "Allow to mount readonly mode only");
 		return -EROFS;
@@ -2035,12 +2039,14 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
 	if (test_opt(sbi, ATGC))
 		seq_puts(seq, ",atgc");
 
-	if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_BLOCK)
-		seq_printf(seq, ",discard_unit=%s", "block");
-	else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SEGMENT)
-		seq_printf(seq, ",discard_unit=%s", "segment");
-	else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SECTION)
-		seq_printf(seq, ",discard_unit=%s", "section");
+	if (test_opt(sbi, DISCARD)) {
+		if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_BLOCK)
+			seq_printf(seq, ",discard_unit=%s", "block");
+		else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SEGMENT)
+			seq_printf(seq, ",discard_unit=%s", "segment");
+		else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SECTION)
+			seq_printf(seq, ",discard_unit=%s", "section");
+	}
 
 	if (F2FS_OPTION(sbi).memory_mode == MEMORY_MODE_NORMAL)
 		seq_printf(seq, ",memory=%s", "normal");
@@ -2081,9 +2087,10 @@ static void default_options(struct f2fs_sb_info *sbi)
 	set_opt(sbi, MERGE_CHECKPOINT);
 	F2FS_OPTION(sbi).unusable_cap = 0;
 	sbi->sb->s_flags |= SB_LAZYTIME;
-	if (!f2fs_sb_has_readonly(sbi) && !f2fs_readonly(sbi->sb))
+	if (!f2fs_is_readonly(sbi))
 		set_opt(sbi, FLUSH_MERGE);
-	if (f2fs_hw_support_discard(sbi) || f2fs_hw_should_discard(sbi))
+	if ((f2fs_hw_support_discard(sbi) || f2fs_hw_should_discard(sbi)) &&
+		!f2fs_is_readonly(sbi))
 		set_opt(sbi, DISCARD);
 	if (f2fs_sb_has_blkzoned(sbi)) {
 		F2FS_OPTION(sbi).fs_mode = FS_MODE_LFS;
@@ -2221,7 +2228,6 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 	bool enable_checkpoint = !test_opt(sbi, DISABLE_CHECKPOINT);
 	bool no_io_align = !F2FS_IO_ALIGNED(sbi);
 	bool no_atgc = !test_opt(sbi, ATGC);
-	bool no_discard = !test_opt(sbi, DISCARD);
 	bool no_compress_cache = !test_opt(sbi, COMPRESS_CACHE);
 	bool block_unit_discard = f2fs_block_unit_discard(sbi);
 	struct discard_cmd_control *dcc;
@@ -2398,19 +2404,18 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 		need_stop_flush = true;
 	}
 
-	if (no_discard == !!test_opt(sbi, DISCARD)) {
-		if (test_opt(sbi, DISCARD)) {
-			err = f2fs_start_discard_thread(sbi);
-			if (err)
-				goto restore_flush;
-			need_stop_discard = true;
-		} else {
-			dcc = SM_I(sbi)->dcc_info;
-			f2fs_stop_discard_thread(sbi);
-			if (atomic_read(&dcc->discard_cmd_cnt))
-				f2fs_issue_discard_timeout(sbi);
-			need_restart_discard = true;
-		}
+	if ((*flags & SB_RDONLY) || !test_opt(sbi, DISCARD)) {
+		clear_opt(sbi, DISCARD);
+		dcc = SM_I(sbi)->dcc_info;
+		f2fs_stop_discard_thread(sbi);
+		if (atomic_read(&dcc->discard_cmd_cnt))
+			f2fs_issue_discard_timeout(sbi);
+		need_restart_discard = true;
+	} else {
+		err = f2fs_start_discard_thread(sbi);
+		if (err)
+			goto restore_flush;
+		need_stop_discard = true;
 	}
 
 	if (enable_checkpoint == !!test_opt(sbi, DISABLE_CHECKPOINT)) {
