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Date:   Mon, 28 Mar 2022 11:38:13 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Shlomo Pongratz <shlomopongratz@gmail.com>
Cc:     linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        andrew.maier@eideticom.com, logang@deltatee.com,
        bhelgaas@google.com
Subject: Re: [PATCH V2 1/1] Intel Sky Lake-E host root ports check.
Message-ID: <20220328143813.GT1342626@nvidia.com>
References: <20220328113728.GA1693573@nvidia.com>
 <20220328143536.20761-1-shlomop@pliops.com>
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On Mon, Mar 28, 2022 at 05:35:36PM +0300, Shlomo Pongratz wrote:
> Hi Jason,
> 
> Thank you for your comments I'll fix the spelling mistakes.
> 
> You suggested to remove the port field and to ignore the slot number for root ports,
> and I understand the reasoning, but, from safety reasons, if we know that device 2030
> will always be found on slot 0 and 2032 for example will always be found on slot 2
> wouldn't it be prudent to compare the device number vs the port number,
> unless you believe that the BIOS/ACPI issue will be fixed.

I'm not sure that is guaranteed, it seems like a BIOS choice..

IMHO what we know is that if we see those devices then we are on a
Skylake-E already and we don't really need more checks.

Jason