If the kernel panic'd while holding the NET_LOCK(), typing "boot reboot"
wont work. The problem is that if_downall() called in boot() tries to
grab the NET_LOCK().
Can we tell rw_enter() to try his best after a panic? This fix my
NET_LOCK() debugging experience.
ok?
Index: kern/kern_rwlock.c
===================================================================
RCS file: /cvs/src/sys/kern/kern_rwlock.c,v
retrieving revision 1.28
diff -u -p -r1.28 kern_rwlock.c
--- kern/kern_rwlock.c 20 Apr 2017 13:33:00 -0000 1.28
+++ kern/kern_rwlock.c 9 Aug 2017 13:58:47 -0000
@@ -236,6 +236,10 @@ retry:
unsigned long set = o | op->wait_set;
int do_sleep;
+ /* Avoid deadlocks after panic */
+ if (panicstr)
+ return (0);
+
rw_enter_diag(rwl, flags);
if (flags & RW_NOSLEEP)
