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Date:   Thu, 21 Jul 2022 21:46:00 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Sagi Grimberg <sagi@grimberg.me>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Yi Zhang <yi.zhang@redhat.com>,
        linux-block <linux-block@vger.kernel.org>,
        "open list:NVM EXPRESS DRIVER" <linux-nvme@lists.infradead.org>
Subject: Re: [bug report] blktests nvme/tcp triggered WARNING at
 kernel/workqueue.c:2628 check_flush_dependency+0x110/0x14c
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On Fri, Jul 22, 2022 at 01:13:26AM +0300, Sagi Grimberg wrote:
> The problem is that nvme_wq is MEM_RECLAIM, and nvme_tcp_wq is
> for the socket threads, that does not need to be MEM_RECLAIM workqueue.

Why don't we need MEM_RECLAIM for the socket threads?

> But reset/error-recovery that take place on nvme_wq, stop nvme-tcp
> queues, and that must involve flushing queue->io_work in order to
> fence concurrent execution.
> 
> So what is the solution? make nvme_tcp_wq MEM_RECLAIM?

I think so.