git: DragonFly_RELEASE_5_4 kernel - Fix nstopped SMP race during core dump

[Matthew Dillon]

commit 9cab665443b9e809e396eb34d9af986673056da1
Author: Matthew Dillon <***@apollo.backplane.com>
Date: Wed Nov 28 22:56:24 2018 -0800

kernel - Fix nstopped SMP race during core dump

* During a process core dump, p->p_nstopped can be adjusted without
holding p->p_token, resulting in a SMP race which can cause
p_nstopped to become permanently desynchronized and deadlock the
process.

* Be robust in a p_nstopped handling case in kern_exit, just in case.

Summary of changes:
sys/kern/kern_exit.c | 2 +-
sys/kern/kern_synch.c | 11 +++++++----
2 files changed, 8 insertions(+), 5 deletions(-)

http://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/9cab665443b9e809e396eb34d9af986673056da1