From mboxrd@z Thu Jan  1 00:00:00 1970
From: Waiman Long <longman@redhat.com>
Date: Tue, 14 Jan 2020 13:33:33 -0500
Subject: [Cluster-devel] [PATCH 02/12] locking/rwsem: Exit early when
 held by an anonymous owner
In-Reply-To: <20200114182514.GA9949@lst.de>
References: <20200114161225.309792-1-hch@lst.de>
	<20200114161225.309792-3-hch@lst.de>
	<925d1343-670e-8f92-0e73-6e9cee0d3ffb@redhat.com>
	<20200114182514.GA9949@lst.de>
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On 1/14/20 1:25 PM, Christoph Hellwig wrote:
> On Tue, Jan 14, 2020 at 01:17:45PM -0500, Waiman Long wrote:
>> The owner field is just a pointer to the task structure with the lower 3
>> bits served as flag bits. Setting owner to RWSEM_OWNER_UNKNOWN (-2) will
>> stop optimistic spinning. So under what condition did the crash happen?
> When running xfstests with all patches in this series except for this
> one, IIRC in generic/114.

OK, I think I know where the bug is. I will send a patch to fix that.

Thanks,
Longman