[Ocfs2-devel] [PATCH] Revert "ocfs2: mount shared volume without ha stack"

[Joseph Qi]

On 6/7/22 11:06 AM, Junxiao Bi wrote:
>>>> Seems I am missing some mails for this thread.
>>>> The 'nocluster' mount is introduced by Gang and I think it has real
>>>> user scenarios. I am curious about since node 0 is commonly used in
>>>> o2cb, why there is no any bug report before.
>>>> So let's try to fix the regression first.
>>> Real user case doesn’t mean this has to been done through kernel? This sounds like doing something in kernel that is to workaround some issue that can be done from user space.
>>> I didn’t see a Reviewed-by for the patch, how did it get merged?
>> Gang had left SUSE for some time, and busy with his new job.
>> I have vague memory, he said this commit approved & merged directly by Andrew Morton.
>> Gang dedicated to contribute ocfs2 community many years, and set up his competence
>> to other maintainers & reviewers.
>>
>> If Junxiao dislike this feature, and don't want to fix it as a bug.
>> I am willing to file a patch.
> To fix, it’s not only the regression it causes, but also do something in mount.ocfs2 to check whether any node is mounting the volume before nocluster mount and also stop other nodes mounting before  nocluster mount is unmounted. That’s to simulate what fsck.ocfs2/mkfs.ocfs2 do. Without that guard, this feature just provides a new way for customer to corrupt their data. It’s just time some customer would do something bad and lost their data. 
> I will leave how to handle this to you and Joseph, we already reverted this patch.

Searched the maillist and find the original thread for reference:
https://lore.kernel.org/ocfs2-devel/CH2PR18MB32064CCD80FE98F03B82A816CFAC0@CH2PR18MB3206.namprd18.prod.outlook.com/

I suggest we leave nocluster mount as a special mode and make its logic
won't impact other mode like cluster or local mount.
Agree with Junxiao, we have to try our best to prevent data corruption
even mistakenly used by customer.

Thanks,
Joseph