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From:   Oded Gabbay <oded.gabbay@gmail.com>
Date:   Sun, 16 Jun 2019 14:24:08 +0300
Message-ID: <CAFCwf11XU1JydbS-wswXBzm4t-fxLjGyXuHCqrNxTsWzLraSZQ@mail.gmail.com>
Subject: Re: [PATCH v2 8/8] habanalabs: enable 64-bit DMA mask in POWER9
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Greg KH <gregkh@linuxfoundation.org>,
        "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>
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On Sun, Jun 16, 2019 at 12:55 PM Christoph Hellwig <hch@infradead.org> wrote:
>
> On Sat, Jun 15, 2019 at 03:12:36PM +0300, Oded Gabbay wrote:
> > So after the dust has settled a bit, do you think it is reasonable to
> > add this patch upstream ?
>
> I'm not Greg, but the answer is a very clear no.  drivers have abslutely
> no business adding these hacks.

So the alternative is that my device won't work on POWER9. Does that make sense?
What is the reason for this logic?
I'm not adding code that will be used by other drivers/users.
I'm just doing a special configuration to my device's H/W and I
condition it upon the PCI device ID of my parent PCI device.
What is the harm in that?

Thanks,
Oded