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Message-ID: <6ac2e3636968832b7bc9a49d6a3f4d4998f9aa20.camel@perches.com>
Subject: Re: [PATCH] checkpatch: forbid filesystem accesses from within the
 kernel
From:   Joe Perches <joe@perches.com>
To:     Prakruthi Deepak Heragu <pheragu@codeaurora.org>, apw@canonical.com
Cc:     linux-kernel@vger.kernel.org, ckadabi@codeaurora.org,
        tsoni@codeaurora.org, bryanh@codeaurora.org
Date:   Thu, 05 Jul 2018 14:56:19 -0700
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On Thu, 2018-07-05 at 14:47 -0700, Prakruthi Deepak Heragu wrote:
> As use of sys_open/close/read/write system calls from within the kernel 
> code is inappropriate, an error is triggered if used.
[]
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -5372,6 +5372,13 @@ sub process {
>  			     "Avoid line continuations in quoted strings\n" . $herecurr);
>  		}
>  
> +# sys_open/read/write/close are not allowed in the kernel
> +		if ($line =~ /\b(sys_(?:open|read|write|close))\b/) {
> +			ERROR("FILE_OPS",
> +			      "$1 is inappropriate in kernel code.\n" .
> +			      $herecurr);
> +		}
> +

Is this really useful?

As far as I can tell, this would only give
false positives on all existing kernel code.