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Message-ID: <1520274223.109662.8.camel@gmail.com>
Subject: Re: [net-next 4/4] e1000e: allocate ring descriptors with
 dma_zalloc_coherent
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>, davem@davemloft.net
Cc: Pierre-Yves Kerbrat <pkerbrat@kalray.eu>, netdev@vger.kernel.org,
        nhorman@redhat.com, sassmann@redhat.com, jogreene@redhat.com,
        Marius Gligor <mgligor@kalray.eu>
Date: Mon, 05 Mar 2018 10:23:43 -0800
In-Reply-To: <20180305181631.3872-5-jeffrey.t.kirsher@intel.com>
References: <20180305181631.3872-1-jeffrey.t.kirsher@intel.com>
         <20180305181631.3872-5-jeffrey.t.kirsher@intel.com>
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On Mon, 2018-03-05 at 10:16 -0800, Jeff Kirsher wrote:
> From: Pierre-Yves Kerbrat <pkerbrat@kalray.eu>
> 
> Descriptor rings were not initialized at zero when allocated
> When area contained garbage data, it caused skb_over_panic in
> e1000_clean_rx_irq (if data had E1000_RXD_STAT_DD bit set)
> 
> This patch makes use of dma_zalloc_coherent to make sure the
> ring is memset at 0 to prevent the area from containing garbage.
> 

This looks like a net candidate, fixing a bug, with 0 chance adding a
regression IMO.