Re: [PATCH v4 2/6] kernfs: Acquire kernfs_rwsem in kernfs_get_parent_dentry().

[Sebastian Andrzej Siewior]

On 2025-01-24 13:11:18 [-1000], Tejun Heo wrote:
> On Fri, Jan 24, 2025 at 06:46:10PM +0100, Sebastian Andrzej Siewior wrote:
> > kernfs_get_parent_dentry() passes kernfs_node::parent to
> > kernfs_get_inode().
> > 
> > Acquire kernfs_root::kernfs_rwsem to ensure kernfs_node::parent isn't
> > replaced during the operation.
> > 
> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> 
> This looks fine but wouldn't it be better to use kernfs_rename_lock instead?

iget_locked() has wait_on_inode()/ alloc_inode() so this looks not
compatible with IRQ off.

> Acked-by: Tejun Heo <tj@xxxxxxxxxx>

Sebastian