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Date:   Wed, 16 Jun 2021 12:16:58 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Chen Li <chenli@uniontech.com>
Cc:     linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] ramfs: skip mknod if inode already exists.
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References: <874kdyh65j.wl-chenli@uniontech.com>
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On Wed, Jun 16, 2021 at 10:53:12AM +0800, Chen Li wrote:
> 
> It's possible we try to mknod a dentry, which have
> already bound to an inode, just skip it.

Caller should have checked may_create(), which includes EEXIST handling.
NAKed-by: Al Viro <viro@zeniv.linux.org.uk>

Incidentally, if it ever had been called that way, your variant would
leak inode.  Not the main problem, though...