Re: [PATCH 0/1] devpts: use dynamic_dname() to generate proc name

From: Linus Torvalds
Date: Wed Aug 16 2017 - 15:56:57 EST


On Wed, Aug 16, 2017 at 12:48 PM, Christian Brauner
<christian.brauner@xxxxxxxxxxxxx> wrote:
>
> I thought - and sorry if I'm completely wrong here - that the proc name came
> from the open(const char *pathname, ...) call.

No. It comes from the path associated with the file descriptor, and is
expanded from the dentry tree.

Which is why you get a full pathname even when you only opened
something using a relative pathname.

So the fact that we _don't_ get the right pathname for the pts entry
here means that something got screwed up in setting filp->f_path to
the right thing. We have all the code in place that _tries_ to do it,
but it clearly has a bug somewhere.

Linus