RE: [PATCH] drm/amdgpu: do not initialise global variables to 0 or NULL

[Deucher, Alexander]

[AMD Public Use]

> -----Original Message-----
> From: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> Sent: Tuesday, November 3, 2020 1:53 AM
> To: Koenig, Christian <Christian.Koenig@xxxxxxx>
> Cc: Alex Deucher <alexdeucher@xxxxxxxxx>; Deepak R Varma
> <mh12gx2825@xxxxxxxxx>; David Airlie <airlied@xxxxxxxx>; LKML <linux-
> kernel@xxxxxxxxxxxxxxx>; Maling list - DRI developers <dri-
> devel@xxxxxxxxxxxxxxxxxxxxx>; Melissa Wen <melissa.srw@xxxxxxxxx>;
> amd-gfx list <amd-gfx@xxxxxxxxxxxxxxxxxxxxx>; Daniel Vetter
> <daniel@xxxxxxxx>; Daniel Vetter <daniel.vetter@xxxxxxxx>; Deucher,
> Alexander <Alexander.Deucher@xxxxxxx>
> Subject: Re: [PATCH] drm/amdgpu: do not initialise global variables to 0 or
> NULL
> 
> On Mon, Nov 02, 2020 at 09:06:21PM +0100, Christian König wrote:
> > Am 02.11.20 um 20:43 schrieb Alex Deucher:
> > > On Mon, Nov 2, 2020 at 1:42 PM Deepak R Varma
> <mh12gx2825@xxxxxxxxx> wrote:
> > > > Initializing global variable to 0 or NULL is not necessary and
> > > > should be avoided. Issue reported by checkpatch script as:
> > > > ERROR: do not initialise globals to 0 (or NULL).
> > > I agree that this is technically correct, but a lot of people don't
> > > seem to know that so we get a lot of comments about this code for
> > > the variables that are not explicitly set.  Seems less confusing to
> > > initialize them even if it not necessary.  I don't have a
> > > particularly strong opinion on it however.
> >
> > Agree with Alex.
> >
> > Especially for the module parameters we should have a explicit init
> > value for documentation purposes, even when it is 0.
> 
> Why is this one tiny driver somehow special compared to the entire rest of
> the kernel?  (hint, it isn't...)
> 
> Please follow the normal coding style rules, there's no reason to ignore them
> unless you like to constantly reject patches like this that get sent to you.
> 

I'll apply the patch, but as a data point, this is the first time I've gotten a patch to make this change.  I get several bug reports or patches every year to explicitly set values to global variables because users assume they are not initialized.  So it will always be a trade off as to which patches you want to NACK.

Alex