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Date: Tue, 6 Feb 2024 10:32:20 -0400
From: Jason Gunthorpe <jgg@ziepe.ca>
To: Konstantin Taranov <kotaranov@microsoft.com>
Cc: Leon Romanovsky <leon@kernel.org>,
	Konstantin Taranov <kotaranov@linux.microsoft.com>,
	"sharmaajay@microsoft.com" <sharmaajay@microsoft.com>,
	Long Li <longli@microsoft.com>,
	"linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH rdma-next v2 2/5] RDMA/mana_ib: Create and destroy rnic
 adapter
Message-ID: <20240206143220.GF31743@ziepe.ca>
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On Tue, Feb 06, 2024 at 02:20:35PM +0000, Konstantin Taranov wrote:

> > Unless you have a good explanation why you can add new FW command to
> > configure RNIC, but can't add FW command to query if RNIC is supported. I'm
> > not keen on adopting this approach.
> 
> The main reason was backward compatibility with old firmware that had the
> aforementioned limitation. Anyway, we will try to internally retire the old firmware
> and will send the v3 patches without the "try and fail" approach (in 2-3 weeks).

I think this is the right thing to do for these cloud devices that can
reliably retire old software. It is how Amazon has been running
EFA. Get your deployment in good shape and then get patches comitted
upstream. No reason to suffer with backwards compatability forever in
the software to save a few weeks.

Jason