9.0-BETA 3 lock order reversal

[Benjamin Kaduk]

On Sat, 8 Oct 2011, Roar Pettersen wrote:

> Hello !
>
>
> Just did a new build of world & kernel, and the error message have changed a
> bit :
>
>
> lock order reversal:
> 1st 0xddf0c4cc bufwait (bufwait) @ /usr/src/sys/kern/vfs_bio.c:2658
> 2nd 0xc4996200 dirhash (dirhash) @ /usr/src/sys/ufs/ufs/ufs_dirhash.c:284

Hi Roar,

Both of these look to be "well-known" (i.e. trivially reproduced) LORs. 
No one seems to have been willing to step up to disable the warnings for 
them or otherwise eliminate them, though, so they still pop up and 
surprise people.

Thanks for taking the time to report them, and sorry that they've been 
sitting untouched for so long.

-Ben Kaduk

[0] http://ipv4.sources.zabbadoz.net/freebsd/lor.html