On Wed, Sep 29, 2021 at 11:04:34AM +0800, Ian Kent wrote: > In kernfs_iop_lookup() a negative dentry is created if there's no kernfs > node associated with the dentry or the node is inactive. > > But inactive kernfs nodes are meant to be invisible to the VFS and > creating a negative dentry for these can have unexpected side effects > when the node transitions to an active state. > > The point of creating negative dentries is to avoid the expensive > alloc/free cycle that occurs if there are frequent lookups for kernfs > attributes that don't exist. So kernfs nodes that are not yet active > should not result in a negative dentry being created so when they > transition to an active state VFS lookups can create an associated > dentry is a natural way. > > Signed-off-by: Ian Kent <raven@xxxxxxxxxx> > --- > fs/kernfs/dir.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) Does this fix a specific commit and need a "Fixes:" tag? thanks, greg k-h
