From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Ferre <nicolas.ferre@microchip.com>
Subject: Re: [PATCH net] net: macb: initialize bp->queues[0].bp for at91rm9200
Date: Tue, 26 Jun 2018 05:51:43 -0700
Message-ID: <5551f74c-9b06-dae1-901b-c9d296ce82ae@microchip.com>
References: <20180626084401.16780-1-alexandre.belloni@bootlin.com>
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Cc: Rafal Ozieblo <rafalo@cadence.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
To: Alexandre Belloni <alexandre.belloni@bootlin.com>,
        "David S. Miller" <davem@davemloft.net>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20180626084401.16780-1-alexandre.belloni@bootlin.com>
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On 26/06/2018 at 01:44, Alexandre Belloni wrote:
> The macb driver currently crashes on at91rm9200 with the following trace:
> 
> Unable to handle kernel NULL pointer dereference at virtual address 00000014
> [...]
> [<c031da44>] (macb_rx_desc) from [<c031f2bc>] (at91ether_open+0x2e8/0x3f8)
> [<c031f2bc>] (at91ether_open) from [<c041e8d8>] (__dev_open+0x120/0x13c)
> [<c041e8d8>] (__dev_open) from [<c041ec08>] (__dev_change_flags+0x17c/0x1a8)
> [<c041ec08>] (__dev_change_flags) from [<c041ec4c>] (dev_change_flags+0x18/0x4c)
> [<c041ec4c>] (dev_change_flags) from [<c07a5f4c>] (ip_auto_config+0x220/0x10b0)
> [<c07a5f4c>] (ip_auto_config) from [<c000a4fc>] (do_one_initcall+0x78/0x18c)
> [<c000a4fc>] (do_one_initcall) from [<c0783e50>] (kernel_init_freeable+0x184/0x1c4)
> [<c0783e50>] (kernel_init_freeable) from [<c0574d70>] (kernel_init+0x8/0xe8)
> [<c0574d70>] (kernel_init) from [<c00090e0>] (ret_from_fork+0x14/0x34)
> 
> Solve that by initializing bp->queues[0].bp in at91ether_init (as is done
> in macb_init).
> 
> Fixes: ae1f2a56d273 ("net: macb: Added support for many RX queues")
> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>

> ---
>   drivers/net/ethernet/cadence/macb_main.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index 3e93df5d4e3b..96cc03a6d942 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -3726,6 +3726,8 @@ static int at91ether_init(struct platform_device *pdev)
>   	int err;
>   	u32 reg;
>   
> +	bp->queues[0].bp = bp;
> +
>   	dev->netdev_ops = &at91ether_netdev_ops;
>   	dev->ethtool_ops = &macb_ethtool_ops;
>   
> 


-- 
Nicolas Ferre