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Date: Thu, 4 Sep 2025 07:24:46 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Conley Lee <conleylee@foxmail.com>
Cc: davem@davemloft.net, wens@csie.org, mripard@kernel.org,
 netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: ethernet: sun4i-emac: free dma descriptor
Message-ID: <20250904072446.5563130d@kernel.org>
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On Wed,  3 Sep 2025 15:49:39 +0800 Conley Lee wrote:
> In the current implementation of the sun4i-emac driver, when using DMA to
> receive data packets, the descriptor for the current DMA request is not
> released in the rx_done_callback.
> 
> Fix this by properly releasing the descriptor.

Reading the docs, it appears that the need to free the desc is tied to
setting descriptor reuse flag. Which this driver does not do. So I'm
unclear why this is needed, maybe the dma engine driver is doing
something strange?

Could you repost this, CC the dmaengine ML, Vinod and the appropriate
SoC maintainers?