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Subject: Re: S3 resume regression [1cf4f629d9d2 ("cpu/hotplug: Move online
 calls to hotplugged cpu")]
To: =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= <ville.syrjala@linux.intel.com>,
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References: <20160511101920.GZ4329@intel.com>
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From: Arjan van de Ven <arjan@linux.intel.com>
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Date: Wed, 11 May 2016 05:44:14 -0700
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On 5/11/2016 3:19 AM, Ville Syrjälä wrote:

> Oh, and this was with acpi_idle. This machine already failed to
> resume from S3 with intel_idle since forever, as detailed in
> https://bugzilla.kernel.org/show_bug.cgi?id=107151
> but acpi_idle worked fine until now.

this is the important clue part afaics.

some of these very old Atom's had issues (bios?) with S3 if the cores were in a too-deep C state,
and at some point there was a workaround (I forgot where in the code) to ban those deep
C states around S3 on those cpus. I wonder if moving things around has made said workaround
ineffective.....