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Date:   Mon, 17 Apr 2023 14:44:25 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Thomas Gleixner <tglx@linutronix.de>,
        Jakub Kicinski <kuba@kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linuxfoundation.org>, x86@kernel.org,
        Wangyang Guo <wangyang.guo@intel.com>,
        Arjan van De Ven <arjan@linux.intel.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        Will Deacon <will@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Boqun Feng <boqun.feng@gmail.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Marc Zyngier <maz@kernel.org>,
        Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Subject: Re: [patch V3 0/4] net, refcount: Address dst_entry reference count
 scalability issues
Message-ID: <20230417114425.GA434718@unreal>
References: <20230323102649.764958589@linutronix.de>
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On Thu, Mar 23, 2023 at 09:55:27PM +0100, Thomas Gleixner wrote:
> Hi!
>=20
> This is version 3 of this series. Version 2 can be found here:
>=20
>      https://lore.kernel.org/lkml/20230307125358.772287565@linutronix.de

Hi,

I want to raise your attention to this bug report from Intel.
https://lore.kernel.org/all/202304162125.18b7bcdd-oliver.sang@intel.com/

We (Nvidia) are experiencing similar failures in our regressions too.
Revert of last two patches [1] from this series removed the panics, but
didn't add confidence due to another (???) netdev failure:

[ +10.080020] unregister_netdevice: waiting for eth3 to become free. Usage =
count =3D 2

Thanks=20

[1]
bc9d3a9f2afc net: dst: Switch to rcuref_t reference counting
d288a162dd1c net: dst: Prevent false sharing vs. dst_entry:: __refcnt