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Date: Mon, 24 Mar 2014 19:17:25 -0700
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Subject: Re: svn commit: r263690 - head/sys/kern
From: Maksim Yevmenkin <emax@freebsd.org>
To: John-Mark Gurney <jmg@funkthat.com>
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On Mon, Mar 24, 2014 at 11:59 AM, John-Mark Gurney <jmg@funkthat.com> wrote:
> Maksim Yevmenkin wrote this message on Mon, Mar 24, 2014 at 18:13 +0000:
>> Author: emax
>> Date: Mon Mar 24 18:13:41 2014
>> New Revision: 263690
>> URL: http://svnweb.freebsd.org/changeset/base/263690
>>
>> Log:
>>   change defaule permissions on /dev/devstat. while i'm here remove
>>   D_NEEDGIANT flag
>
> I know that the following change is part of the remove D_NEEDGIANT, but
> I'm puzzled how this code either worked before, or continues to work..

hmm... beats me too... pagelist is only growing and never shrinking,
and new pages are added to the of the list, so may be that the reason,
i.e. window for race is very small

> It looks like pagelist was suppose to be protected by devstat_mutex,
> but previously wasn't and that this is fixing that bug, is this
> correct?

it should fix it, yes.

thanks
max