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Date:   Thu, 3 Mar 2022 14:10:56 +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,
        spronovo@linux.microsoft.com
Subject: Re: [PATCH v3 02/30] drivers: hv: dxgkrnl: Driver initialization and
 loading
Message-ID: <YiC+YMyEnPDbEepS@kroah.com>
References: <719fe06b7cbe9ac12fa4a729e810e3383ab421c1.1646163378.git.iourit@linux.microsoft.com>
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On Wed, Mar 02, 2022 at 03:27:56PM -0800, Iouri Tarassov wrote:
> 
> On 3/1/2022 12:45 PM, Greg KH wrote:
> > On Tue, Mar 01, 2022 at 11:45:49AM -0800, Iouri Tarassov wrote:
> > > - Create skeleton and add basic functionality for the
> > > hyper-v compute device driver (dxgkrnl).
> > > 
> > > +
> > > +#undef pr_fmt
> > > +#define pr_fmt(fmt)	"dxgk: " fmt
> >
> > Use the dev_*() print functions, you are a driver, and you always have a
> > pointer to a struct device.  There's no need to ever call pr_*().
> >
> 
> There is no struct device during module initialization until the
> /dev/dxg device is created.

Then you should not have anything to print out.

> Is it ok to use pr_* functions in this case?

Nope.

> Should dev_*(NULL,...) be used?

No, not at all, never!

> I see other drivers use the pr_* functions in this case (mips.c as an
> example).

There are lots of bad examples in the kernel tree, let's make your code
a good one.

thanks,

greg k-h