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From:   Claudiu Manoil <claudiu.manoil@nxp.com>
To:     Vladimir Oltean <vladimir.oltean@nxp.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>
CC:     "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH v2 net] net: enetc: survive memory pressure without
 crashing
Thread-Topic: [PATCH v2 net] net: enetc: survive memory pressure without
 crashing
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Date:   Thu, 27 Oct 2022 07:03:31 +0000
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References: <20221026121330.2042989-1-vladimir.oltean@nxp.com>
In-Reply-To: <20221026121330.2042989-1-vladimir.oltean@nxp.com>
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Hi, Vladimir,

> -----Original Message-----
> From: Vladimir Oltean <vladimir.oltean@nxp.com>
> Sent: Wednesday, October 26, 2022 3:14 PM
> To: netdev@vger.kernel.org
[...]
> Subject: [PATCH v2 net] net: enetc: survive memory pressure without crash=
ing
>=20
> Under memory pressure, enetc_refill_rx_ring() may fail, and when called
> during the enetc_open() -> enetc_setup_rxbdr() procedure, this is not
> checked for.
>=20
> An extreme case of memory pressure will result in exactly zero buffers
> being allocated for the RX ring, and in such a case it is expected that
> hardware drops all RX packets due to lack of buffers.
>=20

How do you trigger this "extreme case of memory pressure" where no enetc bu=
ffer
can be allocated? Do you simulate it?

Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>