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Subject: Re: [PATCH] timer: silenct a lockdep splat with debugobjects
From:   Qian Cai <cai@lca.pw>
In-Reply-To: <20200313212620.GA2452@worktop.programming.kicks-ass.net>
Date:   Fri, 13 Mar 2020 22:53:24 -0400
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        John Stultz <john.stultz@linaro.org>, sboyd@kernel.org,
        rostedt@goodmis.org, hannes@cmpxchg.org,
        linux-kernel@vger.kernel.org, Andy Lutomirski <luto@amacapital.net>
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To:     Peter Zijlstra <peterz@infradead.org>
Sender: linux-kernel-owner@vger.kernel.org
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> On Mar 13, 2020, at 5:26 PM, Peter Zijlstra <peterz@infradead.org> =
wrote:
>=20
> On Fri, Mar 13, 2020 at 05:00:41PM -0400, Qian Cai wrote:
>>> On Mar 13, 2020, at 4:13 PM, Peter Zijlstra <peterz@infradead.org> =
wrote:
>=20
>>>=20
>>> Or, fix that random crud to do the wakeup outside of the lock.
>>=20
>> That is likely to be difficult until we can find a creative way to =
not =E2=80=9Cuglifying" the
>> random code by dropping locks in the middle etc just because of =
debugojects.
>=20
> =
https://git.kernel.org/pub/scm/linux/kernel/git/luto/linux.git/log/?h=3Dra=
ndom/fast
>=20
> Doesn't look difficult at all.

Great. I cherry-picked the first two patches,

random: Consolidate entropy batches for u32 and u64
random: Remove batched entropy locking

which solved the issue here as well.

Andy, may I ask what your plan to post those?=