This is a note to let you know that I've just added the patch titled
f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
f2fs-don-t-get-freeze-lock-in-f2fs_evict_inode-in-fr.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 564e865019aa9e8200dd53ab3d05050801ba36af
Author: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Date: Fri Mar 4 09:40:05 2022 -0800
f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs
[ Upstream commit ba900534f807f0b327c92d5141c85d2313e2d55c ]
Let's purge inode cache in order to avoid the below 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)
Reviewed-by: Chao Yu <chao@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index f627e705e663..48d41b669627 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -425,6 +425,7 @@ Description: Show status of f2fs superblock in real time.
0x800 SBI_QUOTA_SKIP_FLUSH skip flushing quota in current CP
0x1000 SBI_QUOTA_NEED_REPAIR quota file may be corrupted
0x2000 SBI_IS_RESIZEFS resizefs is in process
+ 0x4000 SBI_IS_FREEZING freefs is in process
====== ===================== =================================
What: /sys/fs/f2fs/<disk>/ckpt_thread_ioprio
diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index 8c50518475a9..07ad0d81f0c5 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -338,6 +338,7 @@ static char *s_flag[] = {
[SBI_QUOTA_SKIP_FLUSH] = " quota_skip_flush",
[SBI_QUOTA_NEED_REPAIR] = " quota_need_repair",
[SBI_IS_RESIZEFS] = " resizefs",
+ [SBI_IS_FREEZING] = " freezefs",
};
static int stat_show(struct seq_file *s, void *v)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index c68817d83a53..0a0fa1a64d06 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1253,6 +1253,7 @@ enum {
SBI_QUOTA_SKIP_FLUSH, /* skip flushing quota in current CP */
SBI_QUOTA_NEED_REPAIR, /* quota file may be corrupted */
SBI_IS_RESIZEFS, /* resizefs is in process */
+ SBI_IS_FREEZING, /* freezefs is in process */
};
enum {
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 6488f5ff250c..2272000fb10b 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -769,7 +769,8 @@ void f2fs_evict_inode(struct inode *inode)
f2fs_remove_ino_entry(sbi, inode->i_ino, UPDATE_INO);
f2fs_remove_ino_entry(sbi, inode->i_ino, FLUSH_INO);
- sb_start_intwrite(inode->i_sb);
+ if (!is_sbi_flag_set(sbi, SBI_IS_FREEZING))
+ sb_start_intwrite(inode->i_sb);
set_inode_flag(inode, FI_NO_ALLOC);
i_size_write(inode, 0);
retry:
@@ -800,7 +801,8 @@ void f2fs_evict_inode(struct inode *inode)
if (dquot_initialize_needed(inode))
set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
}
- sb_end_intwrite(inode->i_sb);
+ if (!is_sbi_flag_set(sbi, SBI_IS_FREEZING))
+ sb_end_intwrite(inode->i_sb);
no_delete:
dquot_drop(inode);
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 7b744ceb17a5..6dc66b7bc1f5 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1663,11 +1663,15 @@ static int f2fs_freeze(struct super_block *sb)
/* ensure no checkpoint required */
if (!llist_empty(&F2FS_SB(sb)->cprc_info.issue_list))
return -EINVAL;
+
+ /* to avoid deadlock on f2fs_evict_inode->SB_FREEZE_FS */
+ set_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING);
return 0;
}
static int f2fs_unfreeze(struct super_block *sb)
{
+ clear_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING);
return 0;
}
