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Date:   Mon, 26 Apr 2021 13:15:38 -0600
From:   Alex Williamson <alex.williamson@redhat.com>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Shanker R Donthineni <sdonthineni@nvidia.com>,
        Sinan Kaya <okaya@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org, Vikram Sethi <vsethi@nvidia.com>
Subject: Re: [PATCH 1/1] PCI: Add pci reset quirk for Nvidia GPUs
Message-ID: <20210426131538.0b69c69b@redhat.com>
In-Reply-To: <20210426181943.GA1418150@infradead.org>
References: <20210423145402.14559-1-sdonthineni@nvidia.com>
        <ff4812ba-ec1d-9462-0cbd-029635af3267@kernel.org>
        <20210423093701.594efd86@redhat.com>
        <c758d8a8-4f8b-c505-118e-b364e93ae539@nvidia.com>
        <20210426181943.GA1418150@infradead.org>
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On Mon, 26 Apr 2021 19:19:43 +0100
Christoph Hellwig <hch@infradead.org> wrote:

> On Fri, Apr 23, 2021 at 04:45:15PM -0500, Shanker R Donthineni wrote:
> > > specific platforms (embedded device?), and the failure mode of the SBR.  
> > These are not plug-in PCIe GPU cards, will exist on upcoming
> > server baseboards. Triggering SBR without firmware notification  
> 
> Please submit the quirks together with the actual support for the GPUs
> in the nouveau driver, as they are completely useless without that.

My default assumption would be that this resolves an issue with
assigning this device to a userspace or VM driver through vfio-pci, as
most in-kernel drivers don't make use of this interface themselves;
they often know more device specific ways to re-initialize hardware.
This reset path is also trivially accessible through pci-sysfs.  I
don't expect nouveau would have much use for this even if it did
include support for these devices.  Thanks,

Alex