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Date:   Tue, 15 Jun 2021 07:37:06 -0700
From:   Keith Busch <kbusch@kernel.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Jens Axboe <axboe@kernel.dk>,
        Jeffle Xu <jefflexu@linux.alibaba.com>,
        Ming Lei <ming.lei@redhat.com>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
        Sagi Grimberg <sagi@grimberg.me>,
        "Wunderlich, Mark" <mark.wunderlich@intel.com>,
        "Vasudevan, Anil" <anil.vasudevan@intel.com>,
        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-nvme@lists.infradead.org
Subject: Re: switch block layer polling to a bio based model v4
Message-ID: <20210615143706.GB646237@dhcp-10-100-145-180.wdc.com>
References: <20210615131034.752623-1-hch@lst.de>
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On Tue, Jun 15, 2021 at 03:10:18PM +0200, Christoph Hellwig wrote:
> Chances since v3:
>  - rebased to the latests for-5.14/block tree
>  - fix the refcount logic in __blkdev_direct_IO
>  - split up a patch to make it easier to review
>  - grab a queue reference in bio_poll
>  - better document the RCU assumptions in bio_poll

It still doesn't look like a failover will work when polling through
pvsync2. We previously discussed that here:

  https://marc.info/?l=linux-block&m=162100971816071&w=2