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Date: Thu, 27 Oct 2022 02:26:15 +0200
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
To: Marco Elver <elver@google.com>
Cc: kasan-dev@googlegroups.com, patches@lists.linux.dev,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [PATCH] kfence: buffer random bools in bitmask
Message-ID: <Y1nQJ9ZFizv0bzgI@zx2c4.com>
References: <20221026204031.1699061-1-Jason@zx2c4.com>
 <CANpmjNMmHa04Fqf5Ub5-vz6HuqT_Gg8GmEfKD6rv8JeMfBZ32w@mail.gmail.com>
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In-Reply-To: <CANpmjNMmHa04Fqf5Ub5-vz6HuqT_Gg8GmEfKD6rv8JeMfBZ32w@mail.gmail.com>

Hi Marco,

On Wed, Oct 26, 2022 at 05:04:27PM -0700, Marco Elver wrote:
> Is it to avoid depleting the entropy pool?

The entropy pool never depletes, so no.

> kfence_guarded_alloc() is supposed to be a slow-path. And if it were a

Ahh, my huge misunderstanding, then. For some reason, I was under the
general assumption that this got called for every allocation. Given that
this apparently isn't the case, let's indeed just forget I posted this.

This then means, by the way, that there are in fact no fast-path
users of random booleans, which means get_random_bool() is totally
unnecessary. Before I thought this was the one case, hence open coding
it, but luckily that even isn't necessary.

Anyway, sorry for the noise.

Jason