8-stable crashing recently in ufsdirhash

[parv]

On August 5, 2015 4:10:14 AM HST, Ian L
wrote:
>On Tue, 2015-08-04 at 23:54 -1000, parv wrote:
>> Please CC me as I cannot properly use my laptop, Thinkpad X200
>(i386).
>> 
>> 8-stable has been crashing a lot since source update of Jul 2015[0].
>After building debug kernel, kgdb shows lock reversal order & in
>ufsdirhash. File systems (/, var, misc) are all UFS, with var & misc
>having soft updates enabled.
>> 
>> Crash had happened just after boot (during mktemp); when I tried to
>delete a directory (/misc/obj); when I tried to edit (vi /etc/fstab) so
>that / would be mounted readonly. Most recent crash ...
>> 
>> http://imagebin.ca/v/2B50NARvIHsH
>> 
>> Any clue would be appreciated.
...
>When you say you built a debug kernel, does that include option
>WITNESS_KDB?  If so, remove that so you can find the real error.  LORs
>related to ufs_dirhash have been reported for years, and nobody with
>the
>appropriate skills seems to be interested in fixing them; they just get
>declared to be harmless.

I will try that as soon as I can. Currently after every little fs operation, I am thrown in debugger-reboot-fsck cycle. As such I cannot do anything.

This is my own damn fault because the non-debug kernel would run for some random but meaningful amount of time before crash & reboot. I tried booting /boot/kernel.old/kernel from boot prompt but that presented debugger soon after boot.

BTW is it possible to set kernel.old to boot next time at boot prompt?


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