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	Wed, 13 Aug 2025 04:15:06 +0000
Date: Wed, 13 Aug 2025 05:15:06 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: NeilBrown <neil@brown.name>
Cc: Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	David Howells <dhowells@redhat.com>,
	Marc Dionne <marc.dionne@auristor.com>,
	Xiubo Li <xiubli@redhat.com>, Ilya Dryomov <idryomov@gmail.com>,
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Subject: Re: [PATCH 03/11] VFS: add dentry_lookup_killable()
Message-ID: <20250813041506.GZ222315@ZenIV>
References: <20250812235228.3072318-1-neil@brown.name>
 <20250812235228.3072318-4-neil@brown.name>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Tue, Aug 12, 2025 at 12:25:06PM +1000, NeilBrown wrote:
> btrfs/ioctl.c uses a "killable" lock on the directory when creating an
> destroying subvols.  overlayfs also does this.
> 
> This patch adds dentry_lookup_killable() for these users.
> 
> Possibly all dentry_lookup should be killable as there is no down-side,
> but that can come in a later patch.

Same objections re lookup_flags and it would be better to do that
at the same point where you convert the (btrfs and overlayfs?) callers.