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From:   Jonathan Corbet <corbet@lwn.net>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        John Stultz <jstultz@google.com>
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Subject: Re: [PATCH] remove CONFIG_ANDROID
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Date:   Fri, 01 Jul 2022 14:22:38 -0600
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"Jason A. Donenfeld" <Jason@zx2c4.com> writes:

> I guess what I have in mind is the answer to these being "yes":
> - "Is it very common to be asleep for only 2 seconds before being woken?"
> - "Is it very common to be awake for only 2 seconds before sleeping?"
>
> I think it'd be easiest to have a knob somewhere (compiletime,
> runtime, wherever) that describes a device that exhibits those
> properties. Then wireguard and other things will make a decision on how
> to handle the crypto during relevant events.

So please forgive the noise from the peanut gallery, but I do find
myself wondering...do you really need a knob for this?  The kernel
itself can observe how often (and for how long) the system is suspended,
and might well be able to do the right thing without explicit input from
user space.  If it works it would eliminate a potential configuration
problem and also perhaps respond correctly to changing workloads.

For example, rather than testing a knob, avoid resetting keys on resume
if the suspend time is less than (say) 30s?

Educate me on what I'm missing here, please :)

Thanks,

jon