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Date: Fri, 10 May 2024 15:50:57 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: "Paul E. McKenney" <paulmck@kernel.org>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>, RCU <rcu@vger.kernel.org>,
	Neeraj upadhyay <Neeraj.Upadhyay@amd.com>,
	Boqun Feng <boqun.feng@gmail.com>, Hillf Danton <hdanton@sina.com>,
	Joel Fernandes <joel@joelfernandes.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>,
	Frederic Weisbecker <frederic@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 25/48] rcu: Mark writes to rcu_sync ->gp_count field
Message-ID: <20240510135057.GC24764@redhat.com>
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On 05/10, Oleg Nesterov wrote:
>
> On 05/07, Paul E. McKenney wrote:
> >
> > By the stricter data-race rules used in RCU code [1],
> ...
> > [1] https://docs.google.com/document/d/1FwZaXSg3A55ivVoWffA9iMuhJ3_Gmj_E494dLYjjyLQ/edit?usp=sharing
>
> I am getting more and more confused...
>
> Does this mean that KCSAN/etc treats the files in kernel/rcu/
> differently than the "Rest of Kernel"? Or what?
>
> And how is it enforced?

I can only find the strnstr(buf, "rcu") checks in skip_report(),
but they only cover the KCSAN_REPORT_VALUE_CHANGE_ONLY case...

Oleg.