K 10
svn:author
V 6
brooks
K 8
svn:date
V 27
2018-12-04T00:15:47.153933Z
K 7
svn:log
V 693
Remove a needlessly clever hack to start init with sys_exec().

Construct a struct image_args with the help of new exec_args_*() helper
functions and call kern_execve().

The previous code mapped a page in userspace, copied arguments out
to it one at a time, and then constructed a struct execve_args all so
that sys_execve() can call exec_copyin_args() to copy the data back in
to a struct image_args.

Opencode the part of pre_execve()/post_execve() that releases a
reference to the initial vmspace. We don't need to stop threads like
they do.

Reviewed by:	kib, jhb (prior version)
Obtained from:	CheriBSD
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D15469

END