From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Subject: Re: System will not suspend with highest numbered CPU offline [REGRESSION][BISECTED]
Date: Mon, 07 Sep 2015 22:35:20 +0200
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To: Doug Smythies <dsmythies@telus.net>
Cc: 'Viresh Kumar' <viresh.kumar@linaro.org>, "'Rafael J. Wysocki'" <rafael@kernel.org>, 'Saravana Kannan' <skannan@codeaurora.org>, linux-pm@vger.kernel.org

On Monday, September 07, 2015 07:03:16 AM Doug Smythies wrote:
> To wrap this up, I was thinking to file a bug report
> on the pm-utils bug system and then to file a bug against
> the distribution that I use (Ubuntu Server), linking to the
> upstream bug report.
> 
> I don't have it working correctly yet, but I was hoping
> to suggest a fix with the bug reports.
> 
> Something like (still has all my debug stuff also):
> 
> hibernate_cpufreq()
> {
>         ( cd /sys/devices/system/cpu/
>         for x in cpu[0-9]*; do
>                 # if cpufreq is a symlink, it is handled by another cpu. Skip.
>                 [ -L "$x/cpufreq" ] && continue
>                 gov="$x/cpufreq/scaling_governor"
>                 # if we do not have a scaling_governor file, skip.
>                 [ -f "$gov" ] || continue
>                 echo "before $x online check"
> 
> +               # if the CPU is offline, skip, unless no file, i.e. CPU0.
> +               [ $(cat "$x/online") = "1" -o ! -f "$x/online" ] || continue
> Or
> +               if [ $(cat "$x/online") = "1" ] || [ ! -f "$x/online" ]; then
> +                       continue;
> +                fi
> Or something similar that actually works.
> 
>                 echo "after $x online check"
>                 # if our temporary governor is not available, skip.
>                 grep -q "$TEMPORARY_CPUFREQ_GOVERNOR" \
>                         "$x/cpufreq/scaling_available_governors" || continue
>                 savestate "${x}_governor" < "$gov"
>                 echo "$x"
>                 echo "$TEMPORARY_CPUFREQ_GOVERNOR"
>                 echo "$gov"
>                 echo "$TEMPORARY_CPUFREQ_GOVERNOR" > "$gov"
>         done )
> }
> 
> With the proposed fix not dependent on CPU0 at all, just the condition that if
> the file exists, that the CPU be online, and if it doesn't exist then assume the
> CPU is online. As you both pointed out, there is a previous check and skip for
> the no governor or no CPU condition or older kernel conditions.

I guess it also would work if you added

	return 0

at the end of hibernate_cpufreq().

Thanks,
Rafael