Amd64 server randomly panics

[BERTRAND Joël <joel.bertrand%systella.fr@localhost>]

	Hello,

	In last july, I have filled PR-5625 as one of my NetBSD servers
randomly panics (several times by month), mainly on heavy iSCSI I/O
(initiator). This server acts as main server for diskless workstations
(NFSv3 and iSCSI for swap) and when it panics or enters in a deadlock,
all workstations crash.

	I don't know internal kernel enough to fix this issue. I don't know if
someone is working on this PR or if this bug is fixed in 9.99 kernel.
How can I help to fix this bug, I cannot continue with a server that
randomly crash (panic or lock, and I have tested a kernel with LOCKDEBUG
that doesn't reach init stage.).

	Best regards,

	JKB