Trap PC 0xffffffff8102b098 RA 0xffffffff8115dbc0 fault 0x9212daa062ea58a4

bugs@,

I ran a stress test on small non-MP kernel. I compile in the infinity loop
the kernel with -j8 on very small octeon device with 512mb ram and both
/usr/src and /usr/obj in on NFS without any swap at all.

After ~20 hours of that loop the device crashed with following trace.
Machine runs my compiling task and top. And the last one seems crashed and
if I read the trace right it crashed and attemp to write .core trap the
kernel.

Device in ddb now, and I'll keep it in that way in the case if anyone has
any idea 

Some ddb output:

Trap cause = 4 Frame 0x9800000005b1b758
Trap PC 0xffffffff8102b098 RA 0xffffffff8115dbc0 fault 0x9212daa062ea58a4
vnoperm+0x38 (980000041944ee70,a8b7f9fb4ae256e9,9800000001fe6d80,9800000002072f90)  ra 0xffffffff8115dbc0 sp 0x9800000005b1b8b0, sz 0
ufs_access+0x58 (980000041944ee70,6a7ce9235c39fae2,9800000001fe6d80,9800000002072f90)  ra 0xffffffff81052464 sp 0x9800000005b1b8b0, sz 48
VOP_ACCESS+0x74 (980000041944ee70,6a7ce9235c39fae2,9800000001fe6d80,9800000002072f90)  ra 0xffffffff810f649c sp 0x9800000005b1b8e0, sz 48
ufs_lookup+0xac (980000041944ee70,f6bf3fdb09194d4e,9800000001fe6d80,9800000002072f90)  ra 0xffffffff81052064 sp 0x9800000005b1b910, sz 240
VOP_LOOKUP+0x4c (980000041944ee70,9800000005b1bd78,9800000005b1bda8,4a70be816685dde5)  ra 0xffffffff8109c22c sp 0x9800000005b1ba00, sz 48
vfs_lookup+0x404 (980000041944ee70,2ba63f62bb657adc,9800000005b1bda8,4a70be816685dde5)  ra 0xffffffff8109b920 sp 0x9800000005b1ba30, sz 176
User-level: pid 39577
stopped on non ddb fault
Stopped at      vnoperm+0x38:   lw      at,112(v1)
ddb> show proc
PROC (top) tid=381570 pid=39577 tcnt=1 stat=onproc
    flags process=100803<CONTROLT,EXEC,COREDUMP,PLEDGE> proc=2000<WEXIT>
    runpri=24, usrpri=68, slppri=24, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0x9800000002072c98,0x9800000002073590
    process=0x9800000001b62408 user=0x9800000005b18000, vmspace=0x9800000001daa
280
    estcpu=18, cpticks=355157, pctcpu=0.79, user=186728, sys=168428, intr=0
ddb> trace
vnoperm+0x38 (980000041944ee70,a8b7f9fb4ae256e9,9800000001fe6d80,9800000002072f
90)  ra 0xffffffff8115dbc0 sp 0x9800000005b1b8b0, sz 0
ufs_access+0x58 (980000041944ee70,6a7ce9235c39fae2,9800000001fe6d80,98000000020
72f90)  ra 0xffffffff81052464 sp 0x9800000005b1b8b0, sz 48
VOP_ACCESS+0x74 (980000041944ee70,6a7ce9235c39fae2,9800000001fe6d80,98000000020
72f90)  ra 0xffffffff810f649c sp 0x9800000005b1b8e0, sz 48
ufs_lookup+0xac (980000041944ee70,f6bf3fdb09194d4e,9800000001fe6d80,98000000020
72f90)  ra 0xffffffff81052064 sp 0x9800000005b1b910, sz 240
VOP_LOOKUP+0x4c (980000041944ee70,9800000005b1bd78,9800000005b1bda8,4a70be81668
5dde5)  ra 0xffffffff8109c22c sp 0x9800000005b1ba00, sz 48
vfs_lookup+0x404 (980000041944ee70,2ba63f62bb657adc,9800000005b1bda8,4a70be8166
85dde5)  ra 0xffffffff8109b920 sp 0x9800000005b1ba30, sz 176
namei+0x360 (980000041944ee70,2d7dde2f8c58b6b,9800000005b1bda8,4a70be816685dde5
)  ra 0xffffffff814dbb18 sp 0x9800000005b1bae0, sz 176
vn_open+0x138 (980000041944ee70,2d7dde2f8c58b6b,9800000005b1bda8,46944b44028c19
4f)  ra 0xffffffff8111c7c4 sp 0x9800000005b1bb90, sz 240
coredump+0x2cc (980000041944ee70,bf4becf8e7e93b49,9800000005b1bda8,46944b44028c
194f)  ra 0xffffffff8111994c sp 0x9800000005b1bc80, sz 448
sigexit+0x94 (980000041944ee70,bf4becf8e7e93b49,9800000005b1bda8,46944b44028c19
4f)  ra 0xffffffff8111c204 sp 0x9800000005b1be40, sz 32
postsig+0x36c (980000041944ee70,bf4becf8e7e93b49,9800000005b1bda8,cdd00005780fd
70f)  ra 0xffffffff8111d49c sp 0x9800000005b1be60, sz 224
userret+0x164 (980000041944ee70,e1efd9d355a54fc1,9800000005b1bda8,cdd00005780fd
70f)  ra 0xffffffff813f2158 sp 0x9800000005b1bf40, sz 80
trap+0x1f8 (980000041944ee70,2293dafb1f799b63,9800000005b1bda8,cdd00005780fd70f
)  ra 0xffffffff813497e8 sp 0x9800000005b1bf90, sz 64
u_general+0x100 (980000041944ee70,2293dafb1f799b63,9800000005b1bda8,32157b9bcc)
  ra 0x0 sp 0x9800000005b1bfd0, sz 0
User-level: pid 39577
ddb>



-- 
wbr, Kirill