Otherwise, we will get a deadlock.
[freeze test] shrinkder
freeze_super
- pwercpu_down_write(SB_FREEZE_FS)
- super_cache_scan
- down_read(&sb->s_umount)
- prune_icache_sb
- dispose_list
- evict
- f2fs_evict_inode
thaw_super
- down_write(&sb->s_umount);
- __percpu_down_read(SB_FREEZE_FS)
Signed-off-by: Jaegeuk Kim <[email protected]>
---
fs/super.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/fs/super.c b/fs/super.c
index 7af820ba5ad5..f7303d91f874 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -79,6 +79,12 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
if (!trylock_super(sb))
return SHRINK_STOP;
+ /* This prevents inode eviction that requires SB_FREEZE_FS. */
+ if (sb->s_writers.frozen == SB_FREEZE_FS) {
+ up_read(&sb->s_umount);
+ return SHRINK_STOP;
+ }
+
if (sb->s_op->nr_cached_objects)
fs_objects = sb->s_op->nr_cached_objects(sb, sc);
--
2.35.1.616.g0bdcbb4464-goog