Re: [PATCH] staging: comedi: comedi_fops.c: changed type in assignment to unsigned int *

[B K Karthik]

On Wed, Jul 15, 2020 at 4:41 AM B K Karthik <bkkarthik@xxxxxxxxxxxx> wrote:
>
> On Wed, Jul 15, 2020 at 4:31 AM Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Wed, Jul 15, 2020 at 01:56:45PM +0530, B K Karthik wrote:
> > > On Wed, Jul 15, 2020, 12:38 PM Greg Kroah-Hartman <
> > > gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > > On Wed, Jul 15, 2020 at 12:48:13AM -0400, B K Karthik wrote:
> > > > > fixed a sparse warning by changing the type in
> > > > > assignment from void [noderef] __user * to unsigned int *
> > > > > (different address space)
> > > > >
> > > > > Signed-off-by: B K Karthik <karthik.bk2000@xxxxxxxx>
> > > > > ---
> > > > >  drivers/staging/comedi/comedi_fops.c | 2 +-
> > > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/staging/comedi/comedi_fops.c
> > > > b/drivers/staging/comedi/comedi_fops.c
> > > > > index 3f70e5dfac39..4cc012e231b7 100644
> > > > > --- a/drivers/staging/comedi/comedi_fops.c
> > > > > +++ b/drivers/staging/comedi/comedi_fops.c
> > > > > @@ -2956,7 +2956,7 @@ static int get_compat_cmd(struct comedi_cmd *cmd,
> > > > >       cmd->scan_end_arg = v32.scan_end_arg;
> > > > >       cmd->stop_src = v32.stop_src;
> > > > >       cmd->stop_arg = v32.stop_arg;
> > > > > -     cmd->chanlist = compat_ptr(v32.chanlist);
> > > > > +     cmd->chanlist = (unsigned int *) compat_ptr(v32.chanlist);
> > > > >       cmd->chanlist_len = v32.chanlist_len;
> > > > >       cmd->data = compat_ptr(v32.data);
> > > > >       cmd->data_len = v32.data_len;
> > > >
> > > > Always run your patches through checkpatch before sending them, so you
> > > > do not have a grumpy maintainer telling you that you have to run
> > > > checkpatch on your patch before sending them.
> > > >
> > >
> > > I will. Sorry for that.
> > >
> > > But the error that's being shown in this patch is something that comes up
> > > on its own.
> >
> > No it is not.
> >
> > > git format-patch leaves trailing whitespace in blank lines.
> >
> > It does?  Where is any trailing whitespace here?  That's not the issue.
>
> To give you an example,
> 20200714132350.naekk4zqivpuaedi@pesu-pes-edu/">https://lore.kernel.org/lkml/20200714132350.naekk4zqivpuaedi@pesu-pes-edu/
> was a patch i submitted recently.
> This is what checkpatch has to say:
>
> $ perl scripts/checkpatch.pl -f
> ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch
> ERROR: trailing whitespace
> #21: FILE: ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch:21:
> + $
>
> ERROR: trailing whitespace
> #23: FILE: ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch:23:
> + $
>
> ERROR: trailing whitespace
> #30: FILE: ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch:30:
> + $
>
> ERROR: trailing whitespace
> #37: FILE: ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch:37:
> + $
>
> ERROR: trailing whitespace
> #44: FILE: ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch:44:
> + $
>
> ERROR: trailing whitespace
> #51: FILE: ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch:51:
> +-- $
>
> total: 6 errors, 0 warnings, 53 lines checked
>
> NOTE: For some of the reported defects, checkpatch may be able to
>       mechanically convert to the typical style using --fix or --fix-inplace.
>
> NOTE: Whitespace errors detected.
>       You may wish to use scripts/cleanpatch or scripts/cleanfile
>
> ../cbridge/1407d/1/0001-drivers-staging-media-atomisp-pci-css_2401_system-ho.patch
> has style problems, please review.
>
> NOTE: If any of the errors are false positives, please report
>       them to the maintainer, see CHECKPATCH in MAINTAINERS.
>
> Does this happen only to patches I make? Am I making a silly mistake
> while making a patch?
> I use 'git format-patch -1' to generate the patch file.
> If I am going wrong somewhere, please let me know.

Also, The patch I sent (this thread):
$ perl scripts/checkpatch.pl -f
./0001-staging-comedi-comedi_fops.c-changed-void-__user-to-.patch
ERROR: trailing whitespace
#29: FILE: ./0001-staging-comedi-comedi_fops.c-changed-void-__user-to-.patch:29:
+-- $

total: 1 errors, 0 warnings, 31 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

NOTE: Whitespace errors detected.
      You may wish to use scripts/cleanpatch or scripts/cleanfile

./0001-staging-comedi-comedi_fops.c-changed-void-__user-to-.patch has
style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.

Am I using 'git format-patch' or 'checkpatch.pl' the wrong way?

thanks,

karthik