kern/53215: NetBSD/amd64 8.0_RC1 freezes

[babafou+netbsd%babafou.eu.org@localhost]

>Number:         53215
>Category:       kern
>Synopsis:       NetBSD/amd64 8.0_RC1 freezes
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Apr 26 07:10:00 +0000 2018
>Originator:     Marc Baudoin
>Release:        8.0_RC1
>Organization:
>Environment:
NetBSD test.babafou.eu.org 8.0_RC1 NetBSD 8.0_RC1 (PATCH) #0: Wed Apr 25 11:31:33 CEST 2018  babafou%test.babafou.eu.org@localhost:/usr/src/sys/arch/amd64/compile/PATCH amd64

>Description:
Hi,

Since I upgraded my laptop to 8.0_RC1, I've experienced frequent (2-3 times a day) freezes. When the system freezes, the CPU goes full throttle (I know it because of the fan, which is normally silent and that spins very fast and noisy when the CPU is busy). I'm sorry but I don't have any evidence of what's happening (no error message, no crash dump). But it didn't happen with my early 8.0_BETA so it has to be something that has been changed in the 8.0_RC1 cycle (I know, a lot has changed). I'll be happy to test whatever patch anybody can provide because this is very frustrating. Thanks.
>How-To-Repeat:
I can't repeat the problem. It just happens for no particular reason.
>Fix: