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	Sat, 22 Feb 2025 04:56:36 +0000
Date: Sat, 22 Feb 2025 04:56:36 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: NeilBrown <neilb@suse.de>
Cc: Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	Miklos Szeredi <miklos@szeredi.hu>, Xiubo Li <xiubli@redhat.com>,
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Subject: Re: [PATCH 1/6] Change inode_operations.mkdir to return struct
 dentry *
Message-ID: <20250222045636.GP1977892@ZenIV>
References: <20250220234630.983190-1-neilb@suse.de>
 <20250220234630.983190-2-neilb@suse.de>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Fri, Feb 21, 2025 at 10:36:30AM +1100, NeilBrown wrote:

> Not all filesystems reliably result in a positive hashed dentry:
> 
> - NFS, cifs, hostfs will sometimes need to perform a lookup of
>   the name to get inode information.  Races could result in this
>   returning something different. Note that this lookup is
>   non-atomic which is what we are trying to avoid.  Placing the
>   lookup in filesystem code means it only happens when the filesystem
>   has no other option.

At least in case of cifs I don't see that lookup anywhere in your
series.  Have I missed it, or...?