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Date: Sat, 27 Jan 2024 20:31:27 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Tycho Andersen <tycho@tycho.pizza>
Cc: Christian Brauner <brauner@kernel.org>, linux-kernel@vger.kernel.org,
	linux-api@vger.kernel.org, Tycho Andersen <tandersen@netflix.com>,
	"Eric W. Biederman" <ebiederm@xmission.com>
Subject: Re: [PATCH v3 1/3] pidfd: allow pidfd_open() on non-thread-group
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Message-ID: <20240127193127.GC13787@redhat.com>
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On 01/27, Tycho Andersen wrote:
>
> > > > exit_notify() is called after exit_files(). pidfd_getfd() returns
> > > > ESRCH if the exiting thread completes release_task(), otherwise it
> > > > returns EBADF because ->files == NULL. This too doesn't really
> > > > depend on PIDFD_THREAD.
> > >
> > > Yup, understood. It just seems like an inconsistency we might want to
> > > fix.
> >
> > Not sure this worth "fixing"...
>
> Yep, maybe not. Just wanted to point it out.

On the second thought I am starting to understand your concern...

Indeed, in this case -EBADF is technically correct but it can confuse
the user which doesn't or can't know that this task/thread is exiting,
because EBADF looks as if the "int fd" argument was wrong.

Sorry I missed your point before.

Oleg.