Re: kern/37933: very frequent crashes after suspend/resume

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

The following reply was made to PR kern/37933; it has been noted by GNATS.

From: "Steven M. Bellovin" <smb%cs.columbia.edu@localhost>
To: "Jared D. McNeill" <jmcneill%invisible.ca@localhost>
Cc: gnats-bugs%NetBSD.org@localhost, kern-bug-people%NetBSD.org@localhost,
 gnats-admin%NetBSD.org@localhost, netbsd-bugs%NetBSD.org@localhost
Subject: Re: kern/37933: very frequent crashes after suspend/resume
Date: Sun, 10 Feb 2008 16:46:20 +0000

 On Sun, 10 Feb 2008 11:12:27 -0500
 "Jared D. McNeill" <jmcneill%invisible.ca@localhost> wrote:
 
 > Steven M. Bellovin wrote:
 > > On Sat, 09 Feb 2008 21:16:56 -0500
 > > "Jared D. McNeill" <jmcneill%invisible.ca@localhost> wrote:
 > > 
 > >> Are you using cpuctl to offline all APs before you suspend?
 > >>
 > > I hadn't -- should I have?  It does seem to prevent the problem; at
 > > least, I wasn't able to cause any crashes when I tried that.  (To be
 > > sure, I got another crash when I shut down the machine to try that
 > > test; I haven't looked at that dump yet....)
 > > 
 > > For now, I'm going to put a cpuctl in my suspend/resume scripts --
 > > it had reached the point where I was shutting down rather than
 > > risking a second suspend.
 > 
 > I can't remember if I raised a PR on this or not, but there are
 > issues with spinning up the APs as early as we do.
 > 
 > My powerd scripts simply do:
 > 
 >    /usr/sbin/cpuctl offline 1
 >    [..]
 >    sysctl -w machdep.sleep_state=3
 >    [..]
 >    /usr/sbin/cpuctl online 1
 > 
 That's what I'm doing now, too.  I'll run that way for a week -- call
 it data-gathering -- and see if it improves the situation.  (I do have
 a 'sleep 1' after the 'offline' command, to make sure there are no
 problems with asynchrony.)
 
 
                --Steve Bellovin, http://www.cs.columbia.edu/~smb