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	Thu, 30 Oct 2025 06:11:59 +0000
Date: Thu, 30 Oct 2025 06:11:59 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: NeilBrown <neil@brown.name>
Cc: Christian Brauner <brauner@kernel.org>,
	Amir Goldstein <amir73il@gmail.com>, Jan Kara <jack@suse.cz>,
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Subject: Re: [PATCH v4 07/14] VFS: introduce start_removing_dentry()
Message-ID: <20251030061159.GV2441659@ZenIV>
References: <20251029234353.1321957-1-neilb@ownmail.net>
 <20251029234353.1321957-8-neilb@ownmail.net>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Thu, Oct 30, 2025 at 10:31:07AM +1100, NeilBrown wrote:

> @@ -428,11 +429,14 @@ static bool cachefiles_invalidate_cookie(struct fscache_cookie *cookie)
>  		if (!old_tmpfile) {
>  			struct cachefiles_volume *volume = object->volume;
>  			struct dentry *fan = volume->fanout[(u8)cookie->key_hash];
> -
> -			inode_lock_nested(d_inode(fan), I_MUTEX_PARENT);
> -			cachefiles_bury_object(volume->cache, object, fan,
> -					       old_file->f_path.dentry,
> -					       FSCACHE_OBJECT_INVALIDATED);
> +			struct dentry *obj;
> +
> +			obj = start_removing_dentry(fan, old_file->f_path.dentry);
> +			if (!IS_ERR(obj))
> +				cachefiles_bury_object(volume->cache, object,
> +						       fan, obj,
> +						       FSCACHE_OBJECT_INVALIDATED);
> +			end_removing(obj);

Huh?  Where did you change cachefiles_bury_object to *not* unlock the parent?
Not in this commit, AFAICS, and that means at least a bisection hazard around
here...

Confused...