Re: [PATCH] exit: make setting exit_state consistent

[Christian Brauner <christian@brauner.io>]

On Mon, Jul 29, 2019 at 06:27:57PM +0200, Christian Brauner wrote:
> Since commit [1] we unconditionally set exit_state to EXIT_ZOMBIE before
> calling into do_notify_parent(). This was done to eliminate a race when
> querying exit_state in do_notify_pidfd().
> Back then we decided to do the absolute minimal thing to fix this and
> not touch the rest of the exit_notify() function where exit_state is
> set.
> Since this fix has not caused any issues change the setting of
> exit_state to EXIT_DEAD in the autoreap case to account for the fact hat
> exit_state is set to EXIT_ZOMBIE unconditionally. This fix was planned
> but also explicitly requested in [2] and makes the whole code more
> consistent.
> 
> /* References */
> [1]: b191d6491be6 ("pidfd: fix a poll race when setting exit_state")
> [2]: https://lore.kernel.org/lkml/CAHk-=wigcxGFR2szue4wavJtH5cYTTeNES=toUBVGsmX0rzX+g@mail.gmail.com
> 
> Signed-off-by: Christian Brauner <christian@brauner.io>
> Cc: Oleg Nesterov <oleg@redhat.com>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>

I plan on sending this together with a few other fixes later. (Assuming
the change here is correct of course.)

Christian