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Message-ID: <b853a8ab4daface74075e93d83f94655f13a2979.camel@perches.com>
Subject: Re: [PATCH v2] checkpatch: fix false positives in REPEATED_WORD
 warning
From:   Joe Perches <joe@perches.com>
To:     Aditya <yashsri421@gmail.com>
Cc:     linux-kernel@vger.kernel.org,
        linux-kernel-mentees@lists.linuxfoundation.org,
        lukas.bulwahn@gmail.com, dwaipayanray1@gmail.com
Date:   Thu, 22 Oct 2020 15:46:50 -0700
In-Reply-To: <edaa9012-d512-26fc-0aca-f0eaf889a050@gmail.com>
References: <20201022145021.28211-1-yashsri421@gmail.com>
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         <5121bf7c-a126-6178-62ff-e54f0bb4cb6e@gmail.com>
         <67247b2d51aa8b2da7377e400e9191733144ed0f.camel@perches.com>
         <edaa9012-d512-26fc-0aca-f0eaf889a050@gmail.com>
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On Fri, 2020-10-23 at 02:35 +0530, Aditya wrote:
> On 23/10/20 1:03 am, Joe Perches wrote:
> > On Fri, 2020-10-23 at 00:44 +0530, Aditya wrote:
> > > On 22/10/20 9:40 pm, Joe Perches wrote:
> > > > On Thu, 2020-10-22 at 20:20 +0530, Aditya Srivastava wrote:
> > > > > Presence of hexadecimal address or symbol results in false warning
> > > > > message by checkpatch.pl.
> > > > []
> > > > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> > > > []
> > > > > @@ -3051,7 +3051,10 @@ sub process {
> > > > >  		}
> > > > >  
> > > > >  # check for repeated words separated by a single space
> > > > > -		if ($rawline =~ /^\+/ || $in_commit_log) {
> > > > > +# avoid false positive from list command eg, '-rw-r--r-- 1 root root'
> > > > > +		if (($rawline =~ /^\+/ || $in_commit_log) &&
> > > > > +		$rawline !~ /[bcCdDlMnpPs\?-][rwxsStT-]{9}/) {
> > > > 
> > > > Alignment and use \b before and after the regex please.
> > > 
> > > If we use \b either before or after or both it does not match patterns
> > > such as:
> > > +   -rw-r--r--. 1 root root 112K Mar 20 12:16'
> > selinux-policy-3.14.4-48.fc31.noarch.rpm
> > 
> > OK, thanks, it's good you checked.
> > 
> > > > []
> > > > What does all this code actually avoid?
> > > 
> > > Sir, there are multiple variations of hex for which this warning is
> > > occurring, for eg:
> > > 1) 00 c0 06 16 00 00 ff ff 00 93 1c 18 00 00 ff ff  ................
> > > 2) ffffffff ffffffff 00000000 c070058c
> > > 3)     f5a:       48 c7 44 24 78 ff ff    movq
> > > $0xffffffffffffffff,0x78(%rsp)
> > > 4) +    fe fe
> > > 5) +    fe fe   - ? end marker ?
> > > 6) Code: ff ff 48 (...)
> > 
> > So why not just match first with /^[0-9a-f]+$/i ?
> > 
> > Doesn't that match all the cases listed above?
> > 
> > 
> 
> Then, we'll not be able to account for cases such as:
> 
> 1) +     * sets this to -1, the slack value will be calculated to be be
> halfway [For 'be' 'be']
> 2) + * @seg: index of packet segment whose raw fields are to be be
> extracted [For 'be' 'be']
> 3) Let's also add add a note about using only the l3 access without l4
> [For 'add' 'add']

Like the use of long, I think you're better off with
either a list or hash of specific words to ignore.