Date:   Thu, 13 Jan 2022 08:46:05 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Iouri Tarassov <iourit@linux.microsoft.com>
Cc:     kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        wei.liu@kernel.org, linux-hyperv@vger.kernel.org,
        linux-kernel@vger.kernel.org, spronovo@microsoft.com
Subject: Re: [PATCH v1 1/9] drivers: hv: dxgkrnl: Driver initialization and
 creation of dxgadapter
Message-ID: <Yd/YvU5RQOAvLOhC@kroah.com>
References: <cover.1641937419.git.iourit@linux.microsoft.com>
 <1b26482b50832b95a9d8532c493cee6c97323b87.1641937419.git.iourit@linux.microsoft.com>
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On Wed, Jan 12, 2022 at 11:55:06AM -0800, Iouri Tarassov wrote:
> +	dev_dbg(dxgglobaldev, "%s: %x:%x %p %pUb\n",
> +		    __func__, adapter->luid.b, adapter->luid.a, hdev->channel,
> +		    &hdev->channel->offermsg.offer.if_instance);

When I see something like "global device pointer", that is a HUGE red
flag.

No driver should ever have anything that is static to the driver like
this, it should always be per-device.  Please use the correct device
model here, which does not include a global pointer, but rather unique
ones that are given to you by the driver core.  That way you are never
tied to only "one device per system" as that is a constraint that you
will have to fix eventually, might as well do it all correctly the first
time as it is not any extra effort to do so.

thanks,

greg k-h