On Wed, Jun 25, 2025 at 1:07 AM NeilBrown <neil@xxxxxxxxxx> wrote:
>
> Drop the directory lock immediately after the ovl_create_real() call and
> take a separate lock later for cleanup in ovl_cleanup_unlocked() - if
> needed.
>
> This makes way for future changes where locks are taken on individual
> dentries rather than the whole directory.
>
> Signed-off-by: NeilBrown <neil@xxxxxxxxxx>
> ---
> fs/overlayfs/dir.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
> index a51a3dc02bf5..2d67704d641e 100644
> --- a/fs/overlayfs/dir.c
> +++ b/fs/overlayfs/dir.c
> @@ -326,9 +326,10 @@ static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
> ovl_lookup_upper(ofs, dentry->d_name.name,
> upperdir, dentry->d_name.len),
> attr);
> + inode_unlock(udir);
> err = PTR_ERR(newdentry);
> if (IS_ERR(newdentry))
> - goto out_unlock;
> + goto out;
>
> if (ovl_type_merge(dentry->d_parent) && d_is_dir(newdentry) &&
> !ovl_allow_offline_changes(ofs)) {
> @@ -340,14 +341,13 @@ static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
> ovl_dir_modified(dentry->d_parent, false);
inside ovl_dir_modified() =>ovl_dir_version_inc() there is:
WARN_ON(!inode_is_locked(inode));
so why is this WARN_ON not triggered by this change?
either there are more changes that fix it later,
or your tests did not cover this (seems unlikely)
or you did not look in dmesg and overlay fstests do not check for it?
some other explanation?
Thanks,
Amir.
