kern/39774: dirhash kernel panic

[Hauke Fath <hauke%Espresso.Rhein-Neckar.DE@localhost>]

>Number:         39774
>Category:       kern
>Synopsis:       dirhash kernel panic
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Oct 21 08:20:00 +0000 2008
>Originator:     Hauke Fath
>Release:        NetBSD 4.0_STABLE
>Organization:
Falling Raindrops
>Environment:
        
        
System: NetBSD pizza.causeuse.org 4.0_STABLE NetBSD 4.0_STABLE (PIZZA_PF) #0: 
Sat Oct 4 23:35:22 CEST 2008 
hauke%pizza.causeuse.org@localhost:/var/obj/netbsd-builds/4/sparc/sys/arch/sparc/compile/PIZZA_PF
 sparc
Architecture: sparc
Machine: sparc
>Description:

        About once every fortnight, my ss20 panics with a stack trace
        like

db{1}> t
cpu_Debugger(0xf0277358, 0xf01013e8, 0xf55b6bb0, 0xf0293000, 0x100, 0xf02c7400) 
at netbsd:mem_access_fault4m+0x204
mem_access_fault4m(0x9, 0x5336, 0xf55b6bb0, 0xf8d45aa8, 0x0, 0x323a) at 
0xf0006254
0xf0006254(0xa7ec, 0xf8d92228, 0x6, 0x0, 0xae00, 0x24) at 
netbsd:ufsdirhash_build+0x524
ufsdirhash_build(0xae, 0xf74989a8, 0x2c00d, 0x411, 0x40500, 0x2b6) at 
netbsd:ufs_lookup+0x2b4
ufs_lookup(0x0, 0xf42205b0, 0x0, 0x0, 0xf8d45e80, 0x3fff) at 
netbsd:VOP_LOOKUP+0x24
VOP_LOOKUP(0xf74989a8, 0xf8d45e80, 0xf8d45e94, 0x0, 0xf74989a8, 0xf4232406) at 
netbsd:lookup+0x32c
lookup(0xf8d45e70, 0x20002, 0xf8d45cfc, 0x20, 0x0, 0xf4232400) at 
netbsd:namei+0xf8
namei(0x0, 0x0, 0x1000000, 0xf8d45e94, 0xf8d45e70, 0x0) at 
netbsd:sys___lstat30+0x2c
sys___lstat30(0xf5286140, 0xf8d45f20, 0xf8d45f40, 0x2d354, 0x4004e020, 
0xf02c5000) at netbsd:syscall_plain+0xe4
syscall_plain(0x585, 0xf8d45fb0, 0x401505f8, 0x0, 0x0, 0x320b) at 0xf0006574
db{1}> reboot 0x04
rebooting

        usually during the nightly /etc/{daily,security} run. The
        kernel config has "options UFS_DIRHASH" set.

        I have seen this on and off with netbsd-4 kernels since about
        2008-05.

>How-To-Repeat:
        
        Run a netbsd-4 server with a lot of disk space. Sorry for
        being vague here.

>Fix:

        Commenting out "options UFS_DIRHASH", I guess... or fix the
        underlying problem.  ;)

>Unformatted: