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Date: Fri, 31 Jul 2026 11:21:36 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>, Joel Becker <jlbec@evilplan.org>, Heming
 Zhao <heming.zhao@suse.com>, ocfs2-devel@lists.linux.dev,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ocfs2: fix circular locking dependency in reflink
Message-Id: <20260731112136.803da03ad3dd3ed119e88262@linux-foundation.org>
In-Reply-To: <20260731113425.4130293-1-joseph.qi@linux.alibaba.com>
References: <20260731113425.4130293-1-joseph.qi@linux.alibaba.com>
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On Fri, 31 Jul 2026 19:34:25 +0800 Joseph Qi <joseph.qi@linux.alibaba.com> wrote:

> Lockdep reports a possible deadlock involving ip_alloc_sem,
> j_trans_barrier, and ip_xattr_sem:
> 

Cool.

Sashiko said a couple of things:
	https://sashiko.dev/#/patchset/20260731113425.4130293-1-joseph.qi@linux.alibaba.com

> Fix by swapping the lock order in both functions to acquire
> ip_alloc_sem before ip_xattr_sem, consistent with the rest of the
> codebase.
> 
> Fixes: 09bf27a00020 ("ocfs2: Implement ocfs2_reflink.")
> Fixes: 8b2c0dba5159 ("ocfs2: Call refcount tree remove process properly.")

Should we backport this into -stable kernels?