The status of this issue can be tracked through a PR.

System comments

both systems have Tyan S2932 mobo w/ same firmware. Additional IPMI card is installed on both.

Kernels are GENERIC on amd64, with either scheduler.

The lock up issue is consistant and it happens in both systems. The way I have to reproduce it is to ssh remotely over a VPN link and get a buildworld going with the output being shown on the ssh session. It may take a few minutes to occur.

System A:
onboard LSI1068 w/ 2 SAS disks in RAID1
add-on LSI MegaRAID 300 4XLP w/ 4 SATA disks in RAID5

SystemA-SCHED_4BSD_092807.txt
SystemA-dmesg.txt

System B:
Just 1 HD connected to onboard SATA

SystemB-SCHED_ULE_092807.txt
SystemB-dmesg.txt

Fri Sep 28 14:04:09 PDT 2007