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From: Thomas Monjalon <thomas@monjalon.net>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: Ricardo Roldan <rroldan@bequant.com>, users@dpdk.org, dev@dpdk.org
Date: Wed, 13 Dec 2017 22:20:51 +0100
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Subject: Re: [dpdk-dev] [dpdk-users] attach/detach on secondary process
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13/12/2017 22:10, Stephen Hemminger:
> On Wed, 13 Dec 2017 22:00:48 +0100
> Thomas Monjalon <thomas@monjalon.net> wrote:
> 
> > 13/12/2017 18:09, Stephen Hemminger:
> > > Many DPDK drivers require that setup and initialization be done by
> > > the primary process. This is mostly to avoid dealing with concurrency since
> > > there can be multiple secondary processes.  
> > 
> > I think we should consider this limitation as a bug.
> > We must allow a secondary process to initialize a device.
> > The race in device creation must be fixed.
> > 
> 
> Secondary processes should be able to do setup.
> But it is up to the application not to do it concurrently from multiple
> processes.

Yes there can be synchronization between processes.
But I think it is safer to fix the device creation race in ethdev.
Note that I am not talking about configuration concurrency,
but just race in probing.