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Message-ID: <d19605da52eb7aa3eb4132ad1781b5fbf636a8a0.camel@linux.intel.com>
Subject: Re: [PATCH 2/2] nvme: add emulation for zone-append
From:   David Fugate <david.fugate@linux.intel.com>
Reply-To: david.fugate@linux.intel.com
To:     Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
        Kanchan Joshi <joshi.k@samsung.com>
Cc:     "kbusch@kernel.org" <kbusch@kernel.org>,
        "Damien.LeMoal@wdc.com" <Damien.LeMoal@wdc.com>,
        "sagi@grimberg.me" <sagi@grimberg.me>,
        "linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "johannes.thumshirn@wdc.com" <johannes.thumshirn@wdc.com>,
        Nitesh Shetty <nj.shetty@samsung.com>,
        SelvaKumar S <selvakuma.s1@samsung.com>,
        Javier Gonzalez <javier.gonz@samsung.com>,
        david.fugate@intel.com
Date:   Wed, 19 Aug 2020 15:54:20 -0600
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On Wed, 2020-08-19 at 13:25 -0600, Jens Axboe wrote:
> It's not required, the driver will function quite fine without it. If
> you
> want to use ZNS it's required. 

The NVMe spec does not require Zone Append for ZNS; a *vendor-neutral*
Linux driver should not either. 

> The Linux driver thankfully doesn't need
> any vendor to sign off on what it can or cannot do, or what features
> are acceptable.

The problem is the driver needs one *particular* vendor to sign off.
Existing driver behavior aligns with WDC drives instead of the spec,
giving WDC an unfair advantage. Couple this with NVMe maintainer(s?)
working for WDC, and there's a conflict of interest.

> It's *always* ok to reject contributions, if those contributions
> cause
> maintainability issues, unacceptable slowdowns, or whatever other
> issue
> that the maintainers of said driver don't want to deal with. Any
> contribution should be judged on merit, not based on political
> decisions
> or opinions.

Agreed, but this standard needs to be applied equally to everyone.
E.g., harmless contributions such as 
https://lore.kernel.org/linux-nvme/20200611054156.GB3518@lst.de/ get
rejected yet clear spec violations from maintainers are accepted? This
type of behavior encourages forking, vendor-specific drivers, etc.
which is somewhere I hope none of us want to go.