-current panics on boot in atabus_alloc_drives()

[Andreas Gustafsson <gson%gson.org@localhost>]

Christos,

Both i386 and amd64 are failing to install on the testbed due to the
install kernel panicing on boot.  The amd64 console log contains a
backtrace:

  [   1.0264751] panic: lock error: Mutex: mutex_vector_exit,742: exiting unheld spin mutex: lock 0xffffc800003161f0 cpu 0 lwp 0xffffc217e7c90540
  [   1.0264751] cpu0: Begin traceback...
  [   1.2751115] vpanic() at netbsd:vpanic+0x160
  [   1.2751115] snprintf() at netbsd:snprintf
  [   1.3032327] lockdebug_abort() at netbsd:lockdebug_abort+0xee
  [   1.3032327] mutex_vector_exit() at netbsd:mutex_vector_exit+0xbd
  [   1.3032327] atabus_alloc_drives() at netbsd:atabus_alloc_drives+0x61
  [   1.3231953] wdc_drvprobe() at netbsd:wdc_drvprobe+0x40
  [   1.3432056] atabusconfig() at netbsd:atabusconfig+0x65
  [   1.3432056] atabus_thread() at netbsd:atabus_thread+0x7e
  [   1.3432056] cpu0: End traceback...

This is from:

  http://releng.netbsd.org/b5reports/amd64/2019/2019.10.21.19.00.11/install.log

On i386, the only kernel commits between the last sucesss and the failure
were:

  2019.10.21.18.37.47 christos src/sys/dev/ata/ata.c 1.152
  2019.10.21.18.58.57 christos src/sys/dev/ata/ata.c 1.153
  2019.10.21.19.00.11 christos src/sys/dev/pci/satalink.c 1.57

-- 
Andreas Gustafsson, gson%gson.org@localhost