Re: [PATCH 0/4] Rust netlink support + use in Rust Binder

[Alice Ryhl]

On Mon, Mar 09, 2026 at 02:24:00PM -0700, Jakub Kicinski wrote:
> On Sat, 7 Mar 2026 22:50:31 +0000 Alice Ryhl wrote:
> > > > To be honest, I'm not entirely happy with what Binder is using netlink
> > > > for either, but it is what it is.  
> > > 
> > > If we're both not happy let's take this opportunity to find a better
> > > solution?  
> > 
> > My understanding is that userspace is already using or looking into
> > using the netlink uapi that Binder exposes here. I don't know to what
> > extent; it's not used *that* much yet, but it may still be tricky to
> > change the uapi at this point.
> 
> Let's explore it? What user space components would need to be updated?
> What's a better design?

Well ... the thing I'm the most unhappy about is needing to have a
userspace daemon that is notified about all transaction failures to
begin with.

But if you must have such a daemon, I think the netlink based API is
an okay way to do it. You can easily add new fields in the future, and
it implements notifications to userspace on our behalf.

Though using raw pids in the netlink messages is pretty ugly ... pids
can change, and the pid namespace of the receiving proc ends up ignored.

Alice