git: 811e27fa3c44 - main - jail: Add PD_KILL to remove a prison in prison_deref().

[Kyle Evans]

On Tue, Feb 23, 2021 at 7:16 AM Alexander Richardson
<arichardson at freebsd.org> wrote:
>
> On Mon, 22 Feb 2021 at 20:28, Jamie Gritton <jamie at freebsd.org> wrote:
> >
> > The branch main has been updated by jamie:
> >
> > URL: https://cgit.FreeBSD.org/src/commit/?id=811e27fa3c445664e36071a7d08228fc7fb85676
> >
> > commit 811e27fa3c445664e36071a7d08228fc7fb85676
> > Author:     Jamie Gritton <jamie at FreeBSD.org>
> > AuthorDate: 2021-02-22 20:27:44 +0000
> > Commit:     Jamie Gritton <jamie at FreeBSD.org>
> > CommitDate: 2021-02-22 20:27:44 +0000
> >
> >     jail: Add PD_KILL to remove a prison in prison_deref().
> >
> >     Add the PD_KILL flag that instructs prison_deref() to take steps
> >     to actively kill a prison and its descendents, namely marking it
> >     PRISON_STATE_DYING, clearing its PR_PERSIST flag, and killing any
> >     attached processes.
> >
> >     This replaces a similar loop in sys_jail_remove(), bringing the
> >     operation under the same single hold on allprison_lock that it already
> >     has. It is also used to clean up failed jail (re-)creations in
> >     kern_jail_set(), which didn't generally take all the proper steps.
> >
> >     Differential Revision:  https://reviews.freebsd.org/D28473
>
> Hi Jamie,
>
> After this commit running cd /usr/tests/lib/libc/sys && kyua test
> cpuset_test renders the entire system unusable: all exec calls
> afterwards seem to fail. In Jenkins it's triggering a kernel panic:
> https://ci.freebsd.org/job/FreeBSD-main-amd64-test/17630/consoleFull
> Reverting this commit fixes the issue.
>

Based on the backtrace and a wild stab in the dark, the last
prison_deref() in do_jail_attach() prior to successful return should
explicitly clear the PD_KILL flag from drflags.

Thanks,

Kyle Evans