On Fri, Nov 10, 2017 at 04:49:33PM +0000, Fu, Rodney wrote: > The kernel prevents unknown open flags from being passed through to the > underlying filesystem. I am wondering if people would be for or against the > idea of provisioning some number of bits in the open flags that are opaque to > the VFS layer but get passed down to the underlying filesystem? The motivation > would be to allow filesystem specific semantics to be controllable via open, > much like the more generic and pre-existing open flags. Absolutely against. Open flags need to be defined in common code or you are in a massive world of trouble.