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Date: Mon, 25 Dec 2023 02:07:54 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Baokun Li <libaokun1@huawei.com>
Cc: Edward Adam Davis <eadavis@qq.com>,
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Subject: Re: [PATCH] ext4: fix WARNING in lock_two_nondirectories
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On Mon, Dec 25, 2023 at 09:38:51AM +0800, Baokun Li wrote:

> In my opinion, it doesn't make sense to call lock_two_nondirectories()
> here to determine if the inode is a regular file or not, since the logic
> for dealing with non-regular files comes after the locking, so calling
> lock_two_inodes() directly here will suffice.

No.  First of all, lock_two_inodes() is a mistake that is going to be
removed in the coming cycle.

What's more, why the hell do you need to lock *anything* to check the
inode type?  Inode type never changes, period.

Just take that check prior to lock_two_nondirectories() and be done with
that.