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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     Andy Lutomirski <luto@amacapital.net>,
        Jonathan =?utf-8?Q?Neusch=C3=A4fer?= <j.neuschaefer@gmx.net>,
        Theodore Ts'o <tytso@mit.edu>, linux-kernel@vger.kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Waiman Long <longman@redhat.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Andy Lutomirski <luto@kernel.org>, stable@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] random: remove batched entropy locking
Message-ID: <YfQPVp8TULSq3V+l@linutronix.de>
References: <CAHmME9pb9A4SN6TTjNvvxKqw1L3gXVOX7KKihfEH4AgKGNGZ2A@mail.gmail.com>
 <20220128153344.34211-1-Jason@zx2c4.com>
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On 2022-01-28 16:33:44 [+0100], Jason A. Donenfeld wrote:
> From: Andy Lutomirski <luto@kernel.org>
> 
> We don't need spinlocks to protect batched entropy -- all we need
> is a little bit of care. This should fix up the following splat that
> Jonathan received with a PROVE_LOCKING=y/PROVE_RAW_LOCK_NESTING=y
> kernel:

NO. Could we please look at my RANDOM patches first?
This affects PREEMPT_RT. There is no need to stuff this in and tag it
stable.

I can repost my rebased patched if there no objection.
This patch invokes extract_crng() with disabled interrupts so we didn't
gain anything IMHO.

Sebastian