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Date:   Tue, 27 Sep 2022 14:31:30 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Liu Shixin <liushixin2@huawei.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Seth Jennings <sjenning@redhat.com>,
        Dan Streetman <ddstreet@ieee.org>,
        Vitaly Wool <vitaly.wool@konsulko.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nathan Chancellor <nathan@kernel.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Kefeng Wang <wangkefeng.wang@huawei.com>
Subject: Re: [PATCH v5 2/5] Revert "frontswap: simplify
 frontswap_register_ops"
Message-ID: <20220927123130.GA5549@lst.de>
References: <20220915035003.3347466-1-liushixin2@huawei.com> <20220915035003.3347466-3-liushixin2@huawei.com> <20220920121305.GA4237@lst.de> <2b469a5c-7960-ca6a-9360-c7d3aa26e8ae@huawei.com> <20220927072754.GB16710@lst.de> <986efc9f-0deb-f705-dff1-f4d5992c2b8d@huawei.com>
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On Tue, Sep 27, 2022 at 07:12:58PM +0800, Liu Shixin wrote:
> If not do this, while some user enable swap device first and then enable zswap,
> zswap will not take effect. The user need to re-enable the swap device which is
> inconvenient.

So load the module before swapping on, just like you'd load any driver
before you expect to use it.