Hi,
May be related, maybe not ...
I got two crash on antioche. The first one didn't give me a core dump.
The second one did, here's what I can say about it:
(gdb) target kcore netbsd.5.core
panic: trap
#0  0xf01c3eae in sys_sysarch ()
(gdb) where
#0  0xf01c3eae in sys_sysarch ()
#1  0xf01bdb8f in cpu_reboot ()
#2  0xf0121368 in log ()
#3  0xf01c413d in trap ()
#4  0xf0100c9d in calltrap ()
#5  0xf01d8b1d in tulip_intr_handler ()
#6  0xf01d8cd1 in tulip_intr_normal ()
#7  0xf01015c4 in Xintr10 ()
#8  0xf0157b57 in ip_output ()
#9  0xf015c970 in syn_cache_respond ()
#10 0xf015bd7a in syn_cache_get ()
#11 0xf0159dc7 in tcp_input ()
#12 0xf01542d1 in ipintr ()
#13 0xf0101cac in Xsoftnet ()
#14 0xf015e4b3 in tcp_new_iss ()
#15 0xf015c56c in syn_cache_add ()
#16 0xf0159e3e in tcp_input ()
#17 0xf01542d1 in ipintr ()
#18 0xf0101cac in Xsoftnet ()
#19 0xf015e4b3 in tcp_new_iss ()
#20 0xf015c56c in syn_cache_add ()
#21 0xf0159e3e in tcp_input ()
#22 0xf01542d1 in ipintr ()
---Type <return> to continue, or q <return> to quit---
#23 0xf0101cac in Xsoftnet ()
#24 0xf015e4b3 in tcp_new_iss ()
#25 0xf015c56c in syn_cache_add ()
#26 0xf0159e3e in tcp_input ()
#27 0xf01542d1 in ipintr ()
#28 0xf0101cac in Xsoftnet ()
#29 0xf015e4b3 in tcp_new_iss ()
#30 0xf015c56c in syn_cache_add ()
#31 0xf0159e3e in tcp_input ()
#32 0xf01542d1 in ipintr ()
#33 0xf0101cac in Xsoftnet ()
#34 0xf015e4b3 in tcp_new_iss ()
#35 0xf015c56c in syn_cache_add ()
#36 0xf0159e3e in tcp_input ()
#37 0xf01542d1 in ipintr ()
#38 0xf0101cac in Xsoftnet ()
#39 0xf015e4b3 in tcp_new_iss ()
#40 0xf015c56c in syn_cache_add ()
#41 0xf0159e3e in tcp_input ()
#42 0xf01542d1 in ipintr ()
#43 0xf0101cac in Xsoftnet ()
#44 0xf015e4b3 in tcp_new_iss ()
#45 0xf015c56c in syn_cache_add ()
---Type <return> to continue, or q <return> to quit---
#46 0xf0159e3e in tcp_input ()
#47 0xf01542d1 in ipintr ()
#48 0xf0101cac in Xsoftnet ()
#49 0xf015e4b3 in tcp_new_iss ()
#50 0xf015c56c in syn_cache_add ()
#51 0xf0159e3e in tcp_input ()
#52 0xf01542d1 in ipintr ()
#53 0xf0101cac in Xsoftnet ()
#54 0xf015e4b3 in tcp_new_iss ()
#55 0xf015c56c in syn_cache_add ()
#56 0xf0159e3e in tcp_input ()
#57 0xf01542d1 in ipintr ()
#58 0xf0101cac in Xsoftnet ()
#59 0xf015e4b3 in tcp_new_iss ()
#60 0xf015c56c in syn_cache_add ()
#61 0xf0159e3e in tcp_input ()
#62 0xf01542d1 in ipintr ()
#63 0xf0101cac in Xsoftnet ()
#64 0xf01f6dd0 in SHA1Final ()
#65 0xf010f061 in rndpool_extract_data ()
#66 0xf010ecd3 in rnd_extract_data ()
#67 0xf015e4b3 in tcp_new_iss ()
#68 0xf015c56c in syn_cache_add ()
---Type <return> to continue, or q <return> to quit---
#69 0xf0159e3e in tcp_input ()
#70 0xf01542d1 in ipintr ()
#71 0xf0101cac in Xsoftnet ()
#72 0xf015e4b3 in tcp_new_iss ()
#73 0xf015c56c in syn_cache_add ()
#74 0xf0159e3e in tcp_input ()
#75 0xf01542d1 in ipintr ()
#76 0xf0101cac in Xsoftnet ()
can not access 0xefbfdcb0, invalid translation (invalid PDE)
can not access 0xefbfdcb0, invalid translation (invalid PDE)
Cannot access memory at address 0xefbfdcb0.

mrtg on my router reported a higth network traffic at this time, as does the
mrtg running on this host just before the crash.

Could it be possible that the kernel stack got exhausted ?

dmesg:
uvm_fault(0xf0204ce8, 0xf0439000, 0, 3) -> 1
fatal page fault in supervisor mode
trap type 6 code 2 eip f01d8050 cs 8 eflags 10207 cr2 f04393b4 cpl c0001e40
panic: trap
syncing disks... 4 4 3 done

System is a p100 with 100Mbs DEC 21140A ethernet, running www, ftp and sup
services.
www traffic is moderate, but ftp traffic has increased a lot in the last
few days, especially due to what looks like a squid cache which seems
to mirror the whole NetBSD 1.4 tree with several concurent connections.

I took the opportunity to upgrade to 1.4.1, now I'm waiting for the next
crash :)

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
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