Re: [PATCH 5/9] trinity: Add sysfs debugfs module

From: Greg KH <gregkh@linuxfoundation.org>
To: Jiho Chu <jiho.chu@samsung.com>
Cc: arnd@arndb.de, linux-kernel@vger.kernel.org,
	yelini.jeong@samsung.com, myungjoo.ham@samsung.com
Subject: Re: [PATCH 5/9] trinity: Add sysfs debugfs module
Date: Wed, 27 Jul 2022 15:25:16 +0200	[thread overview]
Message-ID: <YuE8vEaA19iPGcfy@kroah.com> (raw)
In-Reply-To: <20220725065308.2457024-6-jiho.chu@samsung.com>

On Mon, Jul 25, 2022 at 03:53:04PM +0900, Jiho Chu wrote:
> This patch includes debugfs and sysfs interfaces.

debugfs and sysfs are two totally different things, with different rules
and requirements.  Split this up into at least 2 different patches and
don't mush them all together.

Would you want to try to review 2000+ lines of this type of thing that
does two totally different things at the same time?

Also, you forgot the sysfs Documentation/ABI/ entries, which are
required as you know.

And finally, you should never do this:

> +int trinity_sysfs_init(struct trinity_driver *drv)
> +{
> +	struct device *dev = drv_to_dev_ptr(drv);
> +	int err;
> +
> +	err = sysfs_create_groups(&dev->kobj, trinity_attrs_groups);

You just raced with userspace and lost.  Use the default groups pointer
for your driver and all will be fine.  Makes for much smaller code that
works properly.

thanks,

greg k-h