Re: rte_eth_dev_attach returns 0, although device is not attached

[Ferruh Yigit <ferruh.yigit@intel.com>]

Hi Igor,

On 8/3/2016 5:58 PM, Igor Ryzhov wrote:
> Hello.
> 
> Function rte_eth_dev_attach can return false positive result.
> It happens because rte_eal_pci_probe_one returns zero if no driver is found for the device:
> ret = pci_probe_all_drivers(dev);
> if (ret < 0)
> 	goto err_return;
> return 0;
> (pci_probe_all_drivers returns 1 in that case)
> 
> For example, it can be easily reproduced by trying to attach virtio device, managed by kernel driver.

You are right, and I did able to reproduce this issue with virtio as you
suggest.

But I wonder why rte_eth_dev_get_port_by_addr() is not catching this.
Perhaps a dev->attached check needs to be added into this function.

> 
> I think it should be:
> ret = pci_probe_all_drivers(dev);
> if (ret)
> 	goto err_return;
> return 0;

Your proposal looks good to me. Will you send a patch?

> Best regards,
> Igor
>