Re: [PATCH bpf-next v2 2/4] xsk: add proper barriers and {READ, WRITE}_ONCE-correctness for state

[Björn Töpel]

On 2019-08-26 17:24, Ilya Maximets wrote:

This changes the error code a bit.
Previously:
    umem exists + xs unbound    --> EINVAL
    no umem     + xs unbound    --> EBADF
    xs bound to different dev/q --> EINVAL

With this change:
    umem exists + xs unbound    --> EBADF
    no umem     + xs unbound    --> EBADF
    xs bound to different dev/q --> EINVAL

Just a note. Not sure if this is important.

Note that this is for *shared* umem, so it's very seldom used. Still,
you're right, that strictly this is an uapi break, but I'd vote for the
change still. I find it hard to see that anyone relies on EINVAL/EBADF
for shared umem bind.

Opinions? :-)


Björn