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Date:   Thu, 26 Nov 2020 10:59:48 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Minchan Kim <minchan@kernel.org>
Cc:     Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        Justin Sanders <justin@coraid.com>,
        Josef Bacik <josef@toxicpanda.com>,
        Ilya Dryomov <idryomov@gmail.com>,
        Jack Wang <jinpu.wang@cloud.ionos.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Roger Pau =?iso-8859-1?Q?Monn=E9?= <roger.pau@citrix.com>,
        Mike Snitzer <snitzer@redhat.com>, Song Liu <song@kernel.org>,
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        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Subject: Re: [PATCH 60/78] zram: remove the claim mechanism
Message-ID: <20201126095948.GA24035@lst.de>
References: <20201116145809.410558-1-hch@lst.de> <20201116145809.410558-61-hch@lst.de> <20201126011107.GA57352@google.com>
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On Wed, Nov 25, 2020 at 05:11:07PM -0800, Minchan Kim wrote:
> With this patch, how deal with the race?
> 
> CPU 1                                     CPU 2
> 
> hot_remove_store
>   zram_remove
>     zram_busy
>       return -EBUSY
>                                          open /dev/zram0
>     del_gendisk
>     zram_reset and destroy

Yeah, it looks like zram does not really handle hot unplugging unlike
other drivers.  So I've dropped this one for now.