[PATCH] hid-wiimote-debug.c: Fix error checking for debugfs_create_file

[PATCH] hid-wiimote-debug.c: Fix error checking for debugfs_create_file

[Osama Muhammad]

This patch fixes the error checking in hid-wiimote-debug.c in
debugfs_create_file. The correct way to check if an error occurred
is 'IS_ERR' inline function.

Signed-off-by: Osama Muhammad <osmtendev@gmail.com>
---
 drivers/hid/hid-wiimote-debug.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/hid-wiimote-debug.c b/drivers/hid/hid-wiimote-debug.c
index a99dcca2e099..eddd981fee1a 100644
--- a/drivers/hid/hid-wiimote-debug.c
+++ b/drivers/hid/hid-wiimote-debug.c
@@ -183,12 +183,12 @@ int wiidebug_init(struct wiimote_data *wdata)
 
 	dbg->eeprom = debugfs_create_file("eeprom", S_IRUSR,
 		dbg->wdata->hdev->debug_dir, dbg, &wiidebug_eeprom_fops);
-	if (!dbg->eeprom)
+	if (IS_ERR(dbg->eeprom))
 		goto err;
 
 	dbg->drm = debugfs_create_file("drm", S_IRUSR,
 			dbg->wdata->hdev->debug_dir, dbg, &wiidebug_drm_fops);
-	if (!dbg->drm)
+	if (IS_ERR(dbg->drm))
 		goto err_drm;
 
 	spin_lock_irqsave(&wdata->state.lock, flags);
-- 
2.34.1

Re: [PATCH] hid-wiimote-debug.c: Fix error checking for debugfs_create_file

[David Rheinsberg]

Hi

On Tue, 23 May 2023 at 19:13, Osama Muhammad <osmtendev@gmail.com> wrote:
>
> This patch fixes the error checking in hid-wiimote-debug.c in
> debugfs_create_file. The correct way to check if an error occurred
> is 'IS_ERR' inline function.

Please have a look at fs/debugfs/inode.c, especiall the docs of
debugfs_create_file():

477  * NOTE: it's expected that most callers should _ignore_ the errors returned
478  * by this function. Other debugfs functions handle the fact that
the "dentry"
479  * passed to them could be an error and they don't crash in that case.
480  * Drivers should generally work fine even if debugfs fails to init anyway.

I think the current code is fine. If you feel like adjusting it, I
would rather just remove the NULL-check.

Thanks
David

> Signed-off-by: Osama Muhammad <osmtendev@gmail.com>
> ---
>  drivers/hid/hid-wiimote-debug.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hid/hid-wiimote-debug.c b/drivers/hid/hid-wiimote-debug.c
> index a99dcca2e099..eddd981fee1a 100644
> --- a/drivers/hid/hid-wiimote-debug.c
> +++ b/drivers/hid/hid-wiimote-debug.c
> @@ -183,12 +183,12 @@ int wiidebug_init(struct wiimote_data *wdata)
>
>         dbg->eeprom = debugfs_create_file("eeprom", S_IRUSR,
>                 dbg->wdata->hdev->debug_dir, dbg, &wiidebug_eeprom_fops);
> -       if (!dbg->eeprom)
> +       if (IS_ERR(dbg->eeprom))
>                 goto err;
>
>         dbg->drm = debugfs_create_file("drm", S_IRUSR,
>                         dbg->wdata->hdev->debug_dir, dbg, &wiidebug_drm_fops);
> -       if (!dbg->drm)
> +       if (IS_ERR(dbg->drm))
>                 goto err_drm;
>
>         spin_lock_irqsave(&wdata->state.lock, flags);
> --
> 2.34.1
>

Re: [PATCH] hid-wiimote-debug.c: Fix error checking for debugfs_create_file

[Osama Muhammad]

Hi,

I will adjust it by sending the revision of the patch by removing NULL-check.

Thanks,
Osmten

On Tue, 30 May 2023 at 15:48, David Rheinsberg
<david.rheinsberg@gmail.com> wrote:
>
> Hi
>
> On Tue, 23 May 2023 at 19:13, Osama Muhammad <osmtendev@gmail.com> wrote:
> >
> > This patch fixes the error checking in hid-wiimote-debug.c in
> > debugfs_create_file. The correct way to check if an error occurred
> > is 'IS_ERR' inline function.
>
> Please have a look at fs/debugfs/inode.c, especiall the docs of
> debugfs_create_file():
>
> 477  * NOTE: it's expected that most callers should _ignore_ the errors returned
> 478  * by this function. Other debugfs functions handle the fact that
> the "dentry"
> 479  * passed to them could be an error and they don't crash in that case.
> 480  * Drivers should generally work fine even if debugfs fails to init anyway.
>
> I think the current code is fine. If you feel like adjusting it, I
> would rather just remove the NULL-check.
>
> Thanks
> David
>
> > Signed-off-by: Osama Muhammad <osmtendev@gmail.com>
> > ---
> >  drivers/hid/hid-wiimote-debug.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/hid/hid-wiimote-debug.c b/drivers/hid/hid-wiimote-debug.c
> > index a99dcca2e099..eddd981fee1a 100644
> > --- a/drivers/hid/hid-wiimote-debug.c
> > +++ b/drivers/hid/hid-wiimote-debug.c
> > @@ -183,12 +183,12 @@ int wiidebug_init(struct wiimote_data *wdata)
> >
> >         dbg->eeprom = debugfs_create_file("eeprom", S_IRUSR,
> >                 dbg->wdata->hdev->debug_dir, dbg, &wiidebug_eeprom_fops);
> > -       if (!dbg->eeprom)
> > +       if (IS_ERR(dbg->eeprom))
> >                 goto err;
> >
> >         dbg->drm = debugfs_create_file("drm", S_IRUSR,
> >                         dbg->wdata->hdev->debug_dir, dbg, &wiidebug_drm_fops);
> > -       if (!dbg->drm)
> > +       if (IS_ERR(dbg->drm))
> >                 goto err_drm;
> >
> >         spin_lock_irqsave(&wdata->state.lock, flags);
> > --
> > 2.34.1
> >