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Date:   Thu, 8 Aug 2019 15:35:10 +0200
From:   Roger Pau =?utf-8?B?TW9ubsOp?= <roger.pau@citrix.com>
To:     Chuhong Yuan <hslester96@gmail.com>
CC:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Jens Axboe <axboe@kernel.dk>, <xen-devel@lists.xenproject.org>,
        <linux-block@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 3/3] xen/blkback: Use refcount_t for refcount
Message-ID: <20190808133510.tre6twn764pv3e7m@Air-de-Roger>
References: <20190808131100.24751-1-hslester96@gmail.com>
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On Thu, Aug 08, 2019 at 09:11:00PM +0800, Chuhong Yuan wrote:
> Reference counters are preferred to use refcount_t instead of
> atomic_t.
> This is because the implementation of refcount_t can prevent
> overflows and detect possible use-after-free.
> So convert atomic_t ref counters to refcount_t.

Thanks!

I think there are more reference counters in blkback than
the one you fixed. There's also an inflight field in xen_blkif_ring,
and a pendcnt in pending_req which look like possible candidates to
switch to use refcount_t, have you looked into switching those two
also?

Roger.