[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <2997c5b0-3611-5e00-466c-b2966f09f067@nbd.name>
Date: Fri, 3 Jun 2022 06:30:42 +0200
From: Felix Fietkau <nbd@....name>
To: Chen Lin <chen45464546@....com>, john@...ozen.org,
sean.wang@...iatek.com, Mark-MC.Lee@...iatek.com
Cc: davem@...emloft.net, edumazet@...gle.com, kuba@...nel.org,
pabeni@...hat.com, matthias.bgg@...il.com, netdev@...r.kernel.org,
linux-arm-kernel@...ts.infradead.org,
linux-mediatek@...ts.infradead.org, linux-kernel@...r.kernel.org,
alexander.duyck@...il.com
Subject: Re: [PATCH] net: ethernet: mtk_eth_soc: fix misuse of mem alloc
interface netdev_alloc_frag
On 03.06.22 06:10, Chen Lin wrote:
> When rx_flag == MTK_RX_FLAGS_HWLRO,
> rx_data_len = MTK_MAX_LRO_RX_LENGTH(4096 * 3) > PAGE_SIZE.
> netdev_alloc_frag is for alloction of page fragment only.
> Reference to other drivers and Documentation/vm/page_frags.rst
>
> Branch to use kmalloc when rx_data_len > PAGE_SIZE.
>
> Signed-off-by: Chen Lin <chen45464546@....com>
> ---
> drivers/net/ethernet/mediatek/mtk_eth_soc.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> index b3b3c07..d0eebca 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> @@ -1914,7 +1914,10 @@ static int mtk_rx_alloc(struct mtk_eth *eth, int ring_no, int rx_flag)
> return -ENOMEM;
>
> for (i = 0; i < rx_dma_size; i++) {
> - ring->data[i] = netdev_alloc_frag(ring->frag_size);
> + if (ring->frag_size <= PAGE_SIZE)
> + ring->data[i] = netdev_alloc_frag(ring->frag_size);
> + else
> + ring->data[i] = kmalloc(ring->frag_size, GFP_KERNEL);
I'm pretty sure you also need to update all the other places in the code
that currently assume that the buffer is allocated using the page frag
allocator.
- Felix
Powered by blists - more mailing lists