misc/52886: Tests hang at pk2_ffs_*

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

>Number:         52886
>Category:       misc
>Synopsis:       Tests hang at pk2_ffs_*
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    misc-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jan 01 12:40:00 +0000 2018
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source-date >= c. 2017-12-28
>Organization:

>Environment:
System: NetBSD
Architecture: sparc
Machine: sparc
>Description:

The sparc test runs on the TNF testbed have hung in ever test run for
the last few days.  First, the 2017.12.27.09.03.22 run hung in the
mtudisc_basic test case, and after that, every run has hung in a test
case whose name begins with "pk2_ffs_":

  2017.12.28.03.39.48    p2k_ffs_overwrite64k
  2017.12.28.07.46.34    p2k_ffs_extendfile
  2017.12.30.03.19.23    p2k_ffs_extendfile
  2017.12.31.11.43.42    p2k_ffs_read_fault
  2017.12.31.15.41.05    p2k_ffs_shrinkfile

There have also been similar hangs on i386 during the same time period, but
not in every test run:

  2017.12.28.17.51.49    p2k_ffs_fcntl_lock
  2017.12.28.18.41.33    p2k_ffs_tmount
  2017.12.29.14.47.09    p2k_ffs_create_nonalphanum
  2017.12.29.16.13.26    p2k_ffs_attrs
  2017.12.31.00.53.29    p2k_ffs_symlink_root
  2017.12.31.11.43.42    p2k_ffs_tfhinval

Here are links to the console output from two of the most recent hung runs:

  http://releng.netbsd.org/b5reports/i386/2017/2017.12.31.11.43.42/test.log
  http://releng.netbsd.org/b5reports/sparc/2017/2017.12.30.03.19.23/test.log

>How-To-Repeat:

>Fix: