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Date:   Sun, 31 Jan 2021 08:13:00 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Avri Altman <Avri.Altman@wdc.com>
Cc:     "James E . J . Bottomley" <jejb@linux.vnet.ibm.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Bart Van Assche <bvanassche@acm.org>,
        yongmyung lee <ymhungry.lee@samsung.com>,
        Daejun Park <daejun7.park@samsung.com>,
        "alim.akhtar@samsung.com" <alim.akhtar@samsung.com>,
        "asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
        Zang Leigang <zangleigang@hisilicon.com>,
        Avi Shchislowski <Avi.Shchislowski@wdc.com>,
        Bean Huo <beanhuo@micron.com>,
        "cang@codeaurora.org" <cang@codeaurora.org>,
        "stanley.chu@mediatek.com" <stanley.chu@mediatek.com>
Subject: Re: [PATCH 1/8] scsi: ufshpb: Cache HPB Control mode on init
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On Sun, Jan 31, 2021 at 07:08:00AM +0000, Avri Altman wrote:
> > >
> > > +static enum UFSHPB_MODE ufshpb_mode;
> > 
> > How are you allowed to have a single variable for a device-specific
> > thing?  What happens when you have two controllers or disks or whatever
> > you are binding to here?  How does this work at all?
> > 
> > This should be per-device, right?
> Right. Done.
> 
> Not being bickering,  AFAIK, there aren't, nor will be in the foreseen future, any multi-ufs-hosts designs.

Why not?  What prevents someone from putting 2 PCI ufs host controllers
in a system tomorrow?

> There were some talks in the past about ufs cards, but this is officially off the table.

Never say never :)

Seriously, how can you somehow ensure that a random manufacturer will
not do this?

thanks,

greg k-h