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Date: Thu, 4 Jan 2024 01:48:37 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Christian Brauner <brauner@kernel.org>,
	linux-fsdevel@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH] tracefs/eventfs: Use root and instance inodes as default
 ownership
Message-ID: <20240104014837.GO1674809@ZenIV>
References: <20240103203246.115732ec@gandalf.local.home>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Wed, Jan 03, 2024 at 08:32:46PM -0500, Steven Rostedt wrote:

> +	/* Get the tracefs root from the parent */
> +	inode = d_inode(dentry->d_parent);
> +	inode = d_inode(inode->i_sb->s_root);

That makes no sense.  First of all, for any positive dentry we have
dentry->d_sb == dentry->d_inode->i_sb.  And it's the same for all
dentries on given superblock.  So what's the point of that dance?
If you want the root inode, just go for d_inode(dentry->d_sb->s_root)
and be done with that...