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Subject: Re: [10-STABLE, 11-CURRENT] something wrong between cam and
 eventtimer or geom and eventtimer
From: Adrian Chadd <adrian@freebsd.org>
To: John Baldwin <jhb@freebsd.org>
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Cc: Davide Italiano <davide@freebsd.org>,
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 "current@freebsd.org" <current@freebsd.org>, Alexander Motin <mav@freebsd.org>,
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.. the main reason to use machdep.idle=hlt is that it is a different code path.

But to ensure you're always going via the hlt codepath, you _first_
have to disable mwait.

The idle code first decides whether to run mwait or <idle>, then if it
doesn't choose mwait, it chooses machdep.idle. That's why you first
have to disable idle_wait.



-adrian