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Date:   Thu, 19 Sep 2019 04:55:31 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     "zhengbin (A)" <zhengbin13@huawei.com>
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Subject: Re: 266a9a8b41: WARNING:possible_recursive_locking_detected
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On Thu, Sep 19, 2019 at 11:36:28AM +0800, zhengbin (A) wrote:

> >> + dput(to);
> >> dput(to) should be in if if (file->f_pos > 2)? cause we dget(to) in scan_positives
> > dput(NULL) is a no-op
> 
> +    spin_unlock(&dentry->d_lock);
> +    dput(*res);
> +    *res = found;
> +    return p;
> 
> dput(*res) should be removed?

Huh?  Why would it?  We drop the original reference and replace it with the
new one; what's the problem?