Re: [PATCH net-next v18 1/6] eea: introduce PCI framework

[Simon Horman <horms@kernel.org>]

On Mon, Jan 05, 2026 at 07:07:07PM +0800, Xuan Zhuo wrote:
> Add basic driver framework for the Alibaba Elastic Ethernet Adapter(EEA).
> 
> This commit implements the EEA PCI probe functionality.
> 
> Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
> Reviewed-by: Philo Lu <lulie@linux.alibaba.com>
> Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>

...

> diff --git a/drivers/net/ethernet/alibaba/eea/eea_pci.c b/drivers/net/ethernet/alibaba/eea/eea_pci.c

...

> +static int eea_pci_setup(struct pci_dev *pci_dev, struct eea_pci_device *ep_dev)
> +{
> +	int err, n, ret;
> +
> +	ep_dev->pci_dev = pci_dev;
> +
> +	err = pci_enable_device(pci_dev);
> +	if (err)
> +		return err;
> +
> +	err = pci_request_regions(pci_dev, "EEA");
> +	if (err)
> +		goto err_disable_dev;
> +
> +	pci_set_master(pci_dev);
> +
> +	err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
> +	if (err) {
> +		dev_warn(&pci_dev->dev, "Failed to enable 64-bit DMA.\n");
> +		goto err_release_regions;
> +	}
> +
> +	ep_dev->reg = pci_iomap(pci_dev, 0, 0);
> +	if (!ep_dev->reg) {
> +		dev_err(&pci_dev->dev, "Failed to map pci bar!\n");
> +		err = -ENOMEM;
> +		goto err_release_regions;
> +	}
> +
> +	ep_dev->edev.rx_num = cfg_read32(ep_dev->reg, rx_num_max);
> +	ep_dev->edev.tx_num = cfg_read32(ep_dev->reg, tx_num_max);
> +
> +	/* 2: adminq, error handle*/
> +	n = ep_dev->edev.rx_num + ep_dev->edev.tx_num + 2;
> +	ret = pci_alloc_irq_vectors(ep_dev->pci_dev, n, n, PCI_IRQ_MSIX);
> +	if (ret != n)
> +		goto err_unmap_reg;

Hi,

As n is passed as both the min_vecs and max_vecs argument of
pci_alloc_irq_vectors() I believe that ret will either be n, on success,
or an negative error value error.

And on error I think it would be appropriate for this function
to return that error value, rather than 0 s is currently the case.

Something like this (completely untested!):

	err = pci_alloc_irq_vectors(ep_dev->pci_dev, n, n, PCI_IRQ_MSIX);
	if (err < 0)
		goto err_unmap_reg;

Function return value portion of the above flagged by Smatch.

> +
> +	ep_dev->msix_vec_n = ret;
> +
> +	ep_dev->db_base = ep_dev->reg + EEA_PCI_DB_OFFSET;
> +	ep_dev->edev.db_blk_size = cfg_read32(ep_dev->reg, db_blk_size);
> +
> +	return 0;
> +
> +err_unmap_reg:
> +	pci_iounmap(pci_dev, ep_dev->reg);
> +	ep_dev->reg = NULL;
> +
> +err_release_regions:
> +	pci_release_regions(pci_dev);
> +
> +err_disable_dev:
> +	pci_disable_device(pci_dev);
> +
> +	return err;
> +}

...

-- 
pw-bot: cr