[dpdk-stable] [dpdk-dev] [PATCH 2/2] bus/fslmc: fix check for vfio_group_fd

[Burakov, Anatoly]

On 17-Sep-20 2:34 PM, wangyunjian wrote:
>> -----Original Message-----
>> From: Burakov, Anatoly [mailto:anatoly.burakov at intel.com]
>> Sent: Thursday, September 17, 2020 8:56 PM
>> To: wangyunjian <wangyunjian at huawei.com>; dev at dpdk.org
>> Cc: hemant.agrawal at nxp.com; sachin.saxena at nxp.com; Lilijun (Jerry)
>> <jerry.lilijun at huawei.com>; xudingke <xudingke at huawei.com>;
>> stable at dpdk.org
>> Subject: Re: [dpdk-dev] [PATCH 2/2] bus/fslmc: fix check for vfio_group_fd
>>
>> On 19-May-20 4:42 AM, wangyunjian wrote:
>>> From: Yunjian Wang <wangyunjian at huawei.com>
>>>
>>> The issue is that a file descriptor at 0 is a valid one. Currently the
>>> file not found, the return value will be set to 0. As a result, it is
>>> impossible to distinguish between a correct descriptor and a failed
>>> return value. Fix it to return -ENOENT instead of 0.
>>>
>>> Fixes: a69f79300262 ("bus/fslmc: support multi VFIO group")
>>> Cc: stable at dpdk.org
>>>
>>> Signed-off-by: Yunjian Wang <wangyunjian at huawei.com>
>>> ---
>>
>> I am unfamiliar with bus/fslmc code but i've taken a quick look, and i've noticed
>> that there's another instance of get_group_fd() usage that you're not
>> modifying - is that intentional?
> 
> Thank you for your review. The another instance of get_group_fd(), is this it?
> int
> fslmc_vfio_setup_group(void) {
>      ...
> 	/* Get the actual group fd */
> 	ret = rte_vfio_get_group_fd(groupid);
> 	if (ret < 0)
> 		return ret;
> 	vfio_group.fd = ret;
>      ...
> }
> I don't think this's necessary. Because it must be a valid descriptor before it can be used.
> 
> Yunjian
> 
>>
>> --
>> Thanks,
>> Anatoly

OK. I'll leave this for fslmc bus maintainers to review, but the patch 
looks fine to me.

Acked-by: Anatoly Burakov <anatoly.burakov at intel.com>

-- 
Thanks,
Anatoly