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Subject: Re: Default enable RCU list lockdep debugging with PROVE_RCU
From:   Qian Cai <cai@lca.pw>
In-Reply-To: <20200514222535.259cb69e@canb.auug.org.au>
Date:   Thu, 14 May 2020 08:31:13 -0400
Cc:     "Paul E. McKenney" <paulmck@kernel.org>,
        Linux Next Mailing List <linux-next@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>,
        Amol Grover <frextrite@gmail.com>,
        Dmitry Vyukov <dvyukov@google.com>
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Message-Id: <ADC503BE-32C0-46BB-A65E-59FFEC30ED57@lca.pw>
References: <20200514222535.259cb69e@canb.auug.org.au>
To:     Stephen Rothwell <sfr@canb.auug.org.au>
Sender: linux-kernel-owner@vger.kernel.org
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> On May 14, 2020, at 8:25 AM, Stephen Rothwell <sfr@canb.auug.org.au> =
wrote:
>=20
> Hi Paul,
>=20
> This patch in the rcu tree
>=20
>  d13fee049fa8 ("Default enable RCU list lockdep debugging with =
PROVE_RCU")
>=20
> is causing whack-a-mole in the syzbot testing of linux-next.  Because
> they always do a debug build of linux-next, no testing is getting =
done. :-(
>=20
> Can we find another way to find all the bugs that are being discovered
> (very slowly)?

Alternatively, could syzbot to use PROVE_RCU=3Dn temporarily because it =
can=E2=80=99t keep up with it? I personally found PROVE_RCU_LIST=3Dy is =
still useful for my linux-next testing, and don=E2=80=99t want to lose =
that coverage overnight.=