Re: [PATCH v6 10/14] dmaengine: dw-edma-pcie: Add register offset match flag

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] IRQ vectors allocated by `pci_alloc_irq_vectors()` are leaked on error paths and during device unbinding.
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--- Patch [10]: [PATCH v6 10/14] dmaengine: dw-edma-pcie: Add register offset match flag ---
commit 96fe59ecf68ecec537def0ad5937dd1f7c596bd9
Author: Koichiro Den <den@valinux.co.jp>

dmaengine: dw-edma-pcie: Add register offset match flag

Add a match-data flag for devices whose DMA register block starts at an
offset inside the mapped BAR. Existing Synopsys EDDA and AMD (Xilinx)
MDB/CPM6 matches keep using the BAR mapping base directly.

> diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
> index 99ddb6e6da348..4b2757c1eda28 100644
> --- a/drivers/dma/dw-edma/dw-edma-pcie.c
> +++ b/drivers/dma/dw-edma/dw-edma-pcie.c

[ ... ]

> @@ -464,6 +465,8 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
>  	chip->reg_base = pcim_iomap_table(pdev)[dma_data->rg.bar];
>  	if (!chip->reg_base)
>  		return -ENOMEM;

[Severity: High]
This is a pre-existing issue, but does this error path leak IRQ vectors?

Looking at dw_edma_pcie_probe(), pci_alloc_irq_vectors() is called earlier
in the function to allocate IRQ resources. However, this direct return on
failure bypasses releasing them.

It looks like other error returns after IRQ allocation, as well as the
dw_edma_pcie_remove() function, might also be missing a call to
pci_free_irq_vectors().

Could we exhaust system IRQ capacity if these resources are leaked during
failed probe attempts or device unbinding?

> +	if (match->flags & DW_EDMA_PCIE_F_REG_OFFSET)
> +		chip->reg_base += dma_data->rg.off;
>  
>  	for (i = 0; i < chip->ll_wr_cnt && !dma_data->cfg_non_ll; i++) {
>  		struct dw_edma_region *ll_region = &chip->ll_region_wr[i];

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Sashiko AI review · https://sashiko.dev/#/patchset/20260721062815.4117887-1-den@valinux.co.jp?part=10