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Date: Mon, 1 Dec 2025 08:56:59 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: NeilBrown <neil@brown.name>
Cc: Amir Goldstein <amir73il@gmail.com>,
	Christian Brauner <brauner@kernel.org>,
	Val Packett <val@packett.cool>, Jan Kara <jack@suse.cz>,
	linux-fsdevel@vger.kernel.org, Jeff Layton <jlayton@kernel.org>,
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	David Howells <dhowells@redhat.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Danilo Krummrich <dakr@kernel.org>, Tyler Hicks <code@tyhicks.com>,
	Miklos Szeredi <miklos@szeredi.hu>,
	Chuck Lever <chuck.lever@oracle.com>,
	Olga Kornievskaia <okorniev@redhat.com>,
	Dai Ngo <Dai.Ngo@oracle.com>, Namjae Jeon <linkinjeon@kernel.org>,
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Subject: Re: [PATCH] fuse: fix conversion of fuse_reverse_inval_entry() to
 start_removing()
Message-ID: <20251201085659.GC3538@ZenIV>
References: <20251113002050.676694-1-neilb@ownmail.net>
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 <6713ea38-b583-4c86-b74a-bea55652851d@packett.cool>
 <176454037897.634289.3566631742434963788@noble.neil.brown.name>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Mon, Dec 01, 2025 at 07:50:43PM +1100, NeilBrown wrote:

> Why was the original code locking the parent inode?  Whatever that was
> protecting, we need to keep protecting it.  That is what
> start_removing_dentry() is there to do.

We need to find out what it's protecting, rather than cargo-culting it
indefinitely.  If nothing else, it's a place with uncommon use of
inode_lock; we need to know which properties of current locking
scheme does it expect there.  Thus the question to Miklos...