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Subject: Re: [Ocfs2-devel] [PATCH v2] ocfs2: Reomve err less than zero check
To:     Wengang Wang <wen.gang.wang@oracle.com>,
        Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "ocfs2-devel@oss.oracle.com" <ocfs2-devel@oss.oracle.com>,
        akpm <akpm@linux-foundation.org>
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 <1EED85DE-EFE1-4FBA-9AA5-648D8E586DD9@oracle.com>
From:   Joseph Qi <joseph.qi@linux.alibaba.com>
Message-ID: <2c9b7d34-01b9-d7de-2334-5d684d29d4eb@linux.alibaba.com>
Date:   Tue, 11 May 2021 10:16:47 +0800
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On 5/10/21 11:50 PM, Wengang Wang wrote:
> Hi Jiapeng,
> 
> Though the type of enum dlm_status has a value range starting from zero,  It can be assigned with negative values without warnings.
> I am wondering why you are sure it can’t be negative?  You went over all the calling path and so you are sure it can’t be negative?
> If you did that, I’d think/guess you should also be able to say it can’t be DLM_MAXSTATS or bigger, right? If not, which calling path are returning >= DLM_MAXSTATS value?
> we should fix that too.
> 
> I’d think we should treat the two conditions of (err >= DLM_MAXSTATS) and the (err < 0) the same way.  If keep, keep both. if remove, remove both.
> I’m suspecting the coccicheck warning is based on the type of enum (starting with 0), but if that’s the only theory to remove (err < 0), It’s NAK from me
DLM_MAXSTATS is a valid value for dlm_status.
Take a look again, I agree with Wengang that we'd better keep the check
here for those misused return code.

Thanks,
Joseph