kern/54806: Many ptrace tests fail on evbarm-aarch64

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         54806
>Category:       kern
>Synopsis:       Many ptrace tests fail on evbarm-aarch64
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Dec 29 10:40:00 +0000 2019
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current since early December 2019
>Organization:

>Environment:
System: NetBSD
Architecture: aarch64
Machine: evbarm
>Description:

More than 100 test cases with "ptrace" in their names started failing
on the TNF evbarm-aarch64 testbed in early December, raising the total
number of unexpected test failures to from about 100 to more than 200.
A recent report showing the failing tests is at:

  http://releng.netbsd.org/b5reports/evbarm-aarch64/2019/2019.12.27.21.55.51/test.html#failed-tcs-summary

This is not easily bisected as the system was hanging due to scheduler
bugs and/or failing to build around the time when the problem appeared.

>How-To-Repeat:

>Fix: