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Date:   Fri, 26 Mar 2021 10:18:34 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Linux PCI <linux-pci@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] PCI: Allow drivers to claim exclusive access to config
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On Thu, Mar 25, 2021 at 10:55:01AM -0700, Dan Williams wrote:
> On Thu, Mar 25, 2021 at 1:29 AM Christoph Hellwig <hch@infradead.org> wrote:
> >
> > On Thu, Mar 25, 2021 at 07:54:59AM +0100, Greg Kroah-Hartman wrote:
> > > On Wed, Mar 24, 2021 at 06:23:54PM -0700, Dan Williams wrote:
> > > > The PCIE Data Object Exchange (DOE) mailbox is a protocol run over
> > > > configuration cycles. It assumes one initiator at a time is
> > > > reading/writing the data registers.
> > >
> > > That sounds like a horrible protocol for a multi-processor system.
> > > Where is it described and who can we go complain to for creating such a
> > > mess?
> >
> > Indeed.  Dan, is there a way to stilk kill this protocol off before it
> > leaks into the wild?
> 
> Unfortunately I think that opportunity was more than a year ago, and
> there's been a proliferation of derivative protocols building on it
> since.

Doesn't mean it can't be changed, right?

Are there any actual devices that require this?

thanks,

greg k-h