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Date:   Fri, 12 May 2023 16:08:36 +0200
From:   Simon Horman <simon.horman@corigine.com>
To:     Stephen Hemminger <stephen@networkplumber.org>
Cc:     Yang Li <yang.lee@linux.alibaba.com>, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Abaci Robot <abaci@linux.alibaba.com>
Subject: Re: [PATCH] ipvlan: Remove NULL check before dev_{put, hold}
Message-ID: <ZF5IZIlUwncUXBHS@corigine.com>
References: <20230511072119.72536-1-yang.lee@linux.alibaba.com>
 <20230511085453.25ef33fc@hermes.local>
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On Thu, May 11, 2023 at 08:54:53AM -0700, Stephen Hemminger wrote:
> On Thu, 11 May 2023 15:21:19 +0800
> Yang Li <yang.lee@linux.alibaba.com> wrote:
> 
> > The call netdev_{put, hold} of dev_{put, hold} will check NULL,
> > so there is no need to check before using dev_{put, hold},
> > remove it to silence the warning:
> > 
> > ./drivers/net/ipvlan/ipvlan_core.c:559:3-11: WARNING: NULL check before dev_{put, hold} functions is not needed.
> > 
> > Reported-by: Abaci Robot <abaci@linux.alibaba.com>
> > Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4930
> > Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
> 
> Maybe add new coccinelle script for this? scripts/free/dev_hold.cocci?

FWIIW, I observe that Coccinelle flags this problem as per the log above.
But perhaps I am missing your point.