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Date: Wed, 11 Dec 2024 18:37:00 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Bernard Metzler <bmt@zurich.ibm.com>, linux-rdma@vger.kernel.org,
 leon@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
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Subject: Re: [PATCH] RDMA/siw: Remove direct link to net_device
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On Wed, 11 Dec 2024 12:00:55 -0400 Jason Gunthorpe wrote:
> > > ifindex is only stable so long as you are holding a reference on the
> > > netdev..  
> > 
> > Does not compute. Can you elaborate what you mean, Jason?  
> 
> I mean you can't replace a netdev pointer with an ifindex, you can't
> reliably get back to the same netdev from ifindex alone.

With the right use of locking and the netdev notifier the ifindex
is as good as a pointer. I just wanted to point out that taking 
a reference makes no difference here.