[PATCH 6.12.y 2/6] super: skip dying superblocks early

[Sasha Levin <sashal@kernel.org>]

From: Christian Brauner <brauner@kernel.org>

[ Upstream commit 6920e3388ba4c66b0468d43bb7a373f5fff15d35 ]

Make all iterators uniform by performing an early check whether the
superblock is dying.

Link: https://lore.kernel.org/r/20250329-work-freeze-v2-3-a47af37ecc3d@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Stable-dep-of: 749d7aa0377a ("super: fix emergency thaw deadlock on frozen block devices")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/super.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/super.c b/fs/super.c
index 5aabfcab4fc7d..f1714752e439b 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -925,6 +925,9 @@ void iterate_supers(void (*f)(struct super_block *, void *), void *arg)
 	list_for_each_entry(sb, &super_blocks, s_list) {
 		bool locked;
 
+		if (super_flags(sb, SB_DYING))
+			continue;
+
 		sb->s_count++;
 		spin_unlock(&sb_lock);
 
@@ -962,6 +965,9 @@ void iterate_supers_type(struct file_system_type *type,
 	hlist_for_each_entry(sb, &type->fs_supers, s_instances) {
 		bool locked;
 
+		if (super_flags(sb, SB_DYING))
+			continue;
+
 		sb->s_count++;
 		spin_unlock(&sb_lock);
 
-- 
2.53.0