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Date:   Thu, 27 Oct 2022 10:58:24 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Vladimir Oltean <vladimir.oltean@nxp.com>
Cc:     netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Claudiu Manoil <claudiu.manoil@nxp.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 net] net: enetc: survive memory pressure without
 crashing
Message-ID: <20221027105824.1c2157a2@kernel.org>
In-Reply-To: <20221026121330.2042989-1-vladimir.oltean@nxp.com>
References: <20221026121330.2042989-1-vladimir.oltean@nxp.com>
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On Wed, 26 Oct 2022 15:13:30 +0300 Vladimir Oltean wrote:
> To fix this problem, memset the DMA coherent area used for RX buffer
> descriptors in enetc_dma_alloc_bdr(). This makes all BDs be "not ready"
> by default, which makes enetc_clean_rx_ring() exit early from the BD
> processing loop when there is no valid buffer available.

IIRC dma_alloc_coherent() always zeros, and I'd guess there is a cocci
script that checks this judging but the number of "fixes" we got for
this in the past.

scripts/coccinelle/api/alloc/zalloc-simple.cocci ?