From: Junxiao Bi <junxiao.bi@oracle.com>
To: ocfs2-devel@oss.oracle.com
Subject: [Ocfs2-devel] [PATCH] ocfs2: dlm: fix recursive locking deadlock
Date: Tue, 15 Dec 2015 09:43:48 +0800 [thread overview]
Message-ID: <566F7054.8030501@oracle.com> (raw)
In-Reply-To: <20151214191827.GF11072@wotan.suse.de>
Hi Mark,
On 12/15/2015 03:18 AM, Mark Fasheh wrote:
> On Mon, Dec 14, 2015 at 02:03:17PM +0800, Junxiao Bi wrote:
>>> Second, this issue can be reproduced in old Linux kernels (e.g. 3.16.7-24)? there should not be any regression issue?
>> Maybe just hard to reproduce, ocfs2 supports recursive locking.
>
> In what sense? The DLM might but the FS should never be making use of such a
> mechanism (it would be for userspace users).
See commit 743b5f1434f5 ("ocfs2: take inode lock in
ocfs2_iop_set/get_acl()"), it used recursive locking and caused a
deadlock, the call trace is in this patch's log.
>
> We really can't add recursive locks without this getting rejected upstream.
> There's a whole slew of reasons why we don't like those in the kernel.
Is there any harm to support this lock in kernel?
Thanks,
Junxiao.
> --Mark
>
> --
> Mark Fasheh
>
next prev parent reply other threads:[~2015-12-15 1:43 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-14 1:57 [Ocfs2-devel] [PATCH] ocfs2: dlm: fix recursive locking deadlock Junxiao Bi
2015-12-14 5:39 ` Gang He
2015-12-14 6:03 ` Junxiao Bi
2015-12-14 8:57 ` Eric Ren
2015-12-14 15:07 ` Junxiao Bi
2015-12-14 19:18 ` Mark Fasheh
2015-12-15 1:43 ` Junxiao Bi [this message]
2015-12-18 23:23 ` Mark Fasheh
2015-12-21 5:12 ` Junxiao Bi
2015-12-22 22:12 ` Mark Fasheh
2015-12-23 2:18 ` Junxiao Bi
2015-12-14 8:44 ` Eric Ren
2015-12-14 9:02 ` Junxiao Bi
2015-12-14 10:14 ` Eric Ren
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