From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: rte_eth_dev_attach returns 0,
 although device is not attached
Date: Thu, 4 Aug 2016 12:33:40 +0100
Message-ID: <57A32814.1000404@intel.com>
References: <E1025756-36BA-4BC3-AA5D-279AE1025530@nfware.com>
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Cc: David Marchand <david.marchand@6wind.com>
To: Igor Ryzhov <iryzhov@nfware.com>, dev@dpdk.org
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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
>