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Subject: Re: [PATCH V2] nvme-rdma: fix double free in nvme_rdma_free_queue
To:     Max Gurtovoy <maxg@mellanox.com>, keith.busch@intel.com,
        axboe@fb.com, hch@lst.de, sagi@grimberg.me
Cc:     linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org
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From:   "jianchao.wang" <jianchao.w.wang@oracle.com>
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Date:   Thu, 17 May 2018 22:50:13 +0800
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Hi Max

Thanks for kindly review and suggestion for this.

On 05/16/2018 08:18 PM, Max Gurtovoy wrote:
> I don't know exactly what Christoph meant but IMO the best place to allocate it is in nvme_rdma_alloc_queue just before calling
> 
> "set_bit(NVME_RDMA_Q_ALLOCATED, &queue->flags);"
> 
> then you will never get to double free since we clear the NVME_RDMA_Q_ALLOCATED bit in the beginning of nvme_rdma_free_queue.

Yes, I will investigate the whether there is some special reason for async_event_sqe is not allocated in nvme_rdma_alloc_queue next.

Thanks
Jianchao