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Subject: Re: [PATCH v5 1/7] scsi: ufs: Add "wb_on" sysfs node to control WB
 on/off
From:   Bean Huo <huobean@gmail.com>
To:     Can Guo <cang@codeaurora.org>
Cc:     Stanley Chu <stanley.chu@mediatek.com>, alim.akhtar@samsung.com,
        avri.altman@wdc.com, asutoshd@codeaurora.org, jejb@linux.ibm.com,
        martin.petersen@oracle.com, beanhuo@micron.com, bvanassche@acm.org,
        tomas.winkler@intel.com, linux-scsi@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Wed, 23 Dec 2020 10:11:05 +0100
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On Wed, 2020-12-23 at 09:31 +0800, Can Guo wrote:
> And assume you come up with a better check,
> you want to add the check everywhere? You must have noticed the fix
> to
> the func ufshcd_clk_gate_enable_store() from Jaegeuk Kim.

Do you mean lock spin_lock_irqsave(hba->host->host_lock, flags)?
It can completely fix race issue, but it is different with here.
ufshcd_clkgate_enable_store() doesn't call ufshcd_hold().
If you want using this lock, we should change ufshcd_hold() and
ufshcd_query_*().

Bean