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Date:   Tue, 30 Mar 2021 11:22:45 +0200
From:   Greg KH <greg@kroah.com>
To:     sj38.park@gmail.com
Cc:     akpm@linux-foundation.org, SeongJae Park <sjpark@amazon.de>,
        Jonathan.Cameron@huawei.com, acme@kernel.org,
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Subject: Re: [PATCH v26 07/13] mm/damon: Implement a debugfs-based user space
 interface
Message-ID: <YGLt5R1AlgGrPtv4@kroah.com>
References: <20210330090537.12143-1-sj38.park@gmail.com>
 <20210330090537.12143-8-sj38.park@gmail.com>
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On Tue, Mar 30, 2021 at 09:05:31AM +0000, sj38.park@gmail.com wrote:
> +static int __init __damon_dbgfs_init(void)
> +{
> +	struct dentry *dbgfs_root;
> +	const char * const file_names[] = {"monitor_on"};
> +	const struct file_operations *fops[] = {&monitor_on_fops};
> +	int i;
> +
> +	dbgfs_root = debugfs_create_dir("damon", NULL);
> +
> +	for (i = 0; i < ARRAY_SIZE(file_names); i++)
> +		debugfs_create_file(file_names[i], 0600, dbgfs_root, NULL,
> +				fops[i]);
> +	dbgfs_fill_ctx_dir(dbgfs_root, dbgfs_ctxs[0]);
> +
> +	dbgfs_dirs = kmalloc_array(1, sizeof(dbgfs_root), GFP_KERNEL);

No error checking for memory allocation failures?


> +	dbgfs_dirs[0] = dbgfs_root;
> +
> +	return 0;
> +}
> +
> +/*
> + * Functions for the initialization
> + */
> +
> +static int __init damon_dbgfs_init(void)
> +{
> +	int rc;
> +
> +	dbgfs_ctxs = kmalloc(sizeof(*dbgfs_ctxs), GFP_KERNEL);

No error checking?

> +	dbgfs_ctxs[0] = dbgfs_new_ctx();
> +	if (!dbgfs_ctxs[0])
> +		return -ENOMEM;
> +	dbgfs_nr_ctxs = 1;
> +
> +	rc = __damon_dbgfs_init();
> +	if (rc)
> +		pr_err("%s: dbgfs init failed\n", __func__);

Shouldn't the error be printed out in the function that failed, not in
this one?

thanks,

greg k-h