On ELFv2, the overflow parameters in the stack frame are at a different offset
from sp than ELFv1. Adjust code to use the correct offset in all cases.
This had resulted in argv[8] and up being copied to the incorrect address
in the new context's initial stack frame.
This is not necessarily the only bug in this function, I need to do a full
review still and ensure the rest of the math is sane for ELFv2 stack frames.
Reported by: pherde (Probably. My notes are a bit unclear.)
Reviewed by: jhibbits (in irc)
Sponsored by: Tag1 Consulting, Inc.
Due to ELFv1 specific code in _ctx_start.S and makecontext.c, userspace
context switching was completely broken on ELFv2.
With this change, we now pass the libthr test suite.
Approved by: jhibbits (mentor)
Differential Revision: https://reviews.freebsd.org/D22421
NCARGS isn't a limit on the number of arguments to pass to a function,
but the number of bytes that can be consumed by arguments to exec. As
such, it is not suitable for a limit on the count of arguments passed
to makecontext().
Sponsored by: DARPA / AFRL
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
