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Date:   Mon, 03 Aug 2020 13:07:39 +0800
From:   Can Guo <cang@codeaurora.org>
To:     Bart Van Assche <bvanassche@acm.org>
Cc:     Stanley Chu <stanley.chu@mediatek.com>,
        Avri Altman <Avri.Altman@wdc.com>, linux-scsi@vger.kernel.org,
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        chun-hung.wu@mediatek.com, andy.teng@mediatek.com,
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Subject: Re: [PATCH v4] scsi: ufs: Cleanup completed request without interrupt
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Hi Bart,

On 2020-08-03 11:12, Bart Van Assche wrote:
> On 2020-07-31 16:17, Can Guo wrote:
>> For scsi_dma_unmap() part, that is true - we should make it serialized 
>> with
>> any other completion paths. I've found it during my fault injection 
>> test, so
>> I've made a patch to fix it, but it only comes in my next error 
>> recovery
>> enhancement patch series. Please check the attachment.
> 
> Hi Can,
> 
> It is not clear to me how that patch serializes scsi_dma_unmap() 
> against
> other completion paths? Doesn't the regular completion path call
> __ufshcd_transfer_req_compl() without holding the host lock?
> 
> Thanks,
> 
> Bart.

FYI, ufshcd_intr() holds the host spin lock the whole time. So, to your
question, the regular completion path from IRQ handler has the host lock 
held.

Thanks,

Can Guo.