Re: [PATCH v2] eal/devargs: add option to supply PCI dev args

[Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>]

Hi Gaëtan,

On Wed, Jun 27, 2018 at 10:39:59AM +0200, Gaëtan Rivet wrote:
> Hi Ferruh, Pavan,
>
> sorry for the delay,
>
> On Tue, Jun 26, 2018 at 04:40:21PM +0100, Ferruh Yigit wrote:
> > On 6/26/2018 1:48 PM, Shahaf Shuler wrote:
> > > Hi Pavan,
> > >
> > > Friday, June 15, 2018 7:44 AM, Pavan Nikhilesh:
> > >> Subject: [dpdk-dev] [PATCH v2] eal/devargs: add option to supply PCI dev
> > >> args
> > >>
> > >> Currently, the only way of supplying device argument to a pci device is to
> > >> whitelist it i.e. -w 000X:00:0X.0,self_test=1. This is not a very feasible method
> > >> as whitelisting a device has its own side effects i.e only the whitelisted pci
> > >> devices are probed.
> > >>
> > >> Add a new eal command line option --pci-args to pass device args without the
> > >> need to whitelist the devices.
> > >>            --pci-args 000X:00:0X.0,self_test=1
> > >>
> > >> Signed-off-by: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
> > >
> > > Tested-by: Shahaf Shuler <shahafs@mellanox.com>
> > >
> > > It seems to work.
> > > Please see small comments below
> >
> > Isn't this conflict with Gaetan's devarg work which has wider scope?
> >
>
> Indeed it does.
>
> Pavan, I have submitted a new version of a series adding generic kvargs
> to several layers (bus, class, driver).
>
> It does cover this exact use-case.
>
> However, while writing it, I wasn't able to find PCI bus specific
> parameters, that could showcase the functionality.

The idea of the patch is to avoid whitelising a device when we want to
supply kvargs to it, I tried mapping it to devargs rework patchset but couldn't
do it at a glance. For example, the following patch[1] reads kvargs through
whitelisting which should be avoided.

[1]http://patches.dpdk.org/patch/41223/

>
> It would help the development if you could provide which parameter you
> wanted to implement, I could add it in my own series, which would
> streamline all of this.

+1

>
> Regards,
> --
> Gaëtan Rivet
> 6WIND

Thanks,
Pavan.