Re: [PATCH 2/3] dmaengine: dw-axi-dmac: Report failed transfers in the descriptor result

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] dmaengine: dw-axi-dmac: missing residue update on error leaves it as 0
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commit 0cfa0e9416a64e0fa0850f1489894a836df68692
Author: Roland Dreier <rolanddreier@rivian.com>

dmaengine: dw-axi-dmac: Report failed transfers in the descriptor result

This commit updates axi_chan_handle_err() to populate tx_result.result with an
error state. It previously completed failed descriptors without updating
vd->tx_result, which returned DMA_TRANS_NOERROR to clients even after failures.

> diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> index 813d17a278e72..88362f1812071 100644
> --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> @@ -1084,6 +1084,13 @@ static noinline void axi_chan_handle_err(struct axi_dma_chan *chan, u32 status)
>  		axi_chan_name(chan), vd->tx.cookie, status);
>  	axi_chan_list_dump_lli(chan, vd_to_axi_desc(vd));
>  
> +	if (status & (DWAXIDMAC_IRQ_SRC_DEC_ERR | DWAXIDMAC_IRQ_SRC_SLV_ERR))
> +		vd->tx_result.result = DMA_TRANS_READ_FAILED;
> +	else if (status & (DWAXIDMAC_IRQ_DST_DEC_ERR | DWAXIDMAC_IRQ_DST_SLV_ERR))
> +		vd->tx_result.result = DMA_TRANS_WRITE_FAILED;
> +	else
> +		vd->tx_result.result = DMA_TRANS_ABORTED;
> +

[Severity: Medium]
Because vd->tx_result.residue is not updated here, it defaults to 0, which
indicates a full transfer completion despite the assigned error state.

Clients inspecting the residue to determine how much data was successfully
transferred before the error will incorrectly conclude that all data was
transferred.

Should this code also update the vd->tx_result.residue field?

>  	vchan_cookie_complete(vd);
>  
>  	/* Try to restart the controller */

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Sashiko AI review · https://sashiko.dev/#/patchset/20261006-dw-axi-fixes-v1-0-3b319e456d93@rivian.com?part=2