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Message-ID: <61984ab3-1bcf-44e4-8b2a-0760af3cefd9@acm.org>
Date: Thu, 23 May 2024 16:05:14 -0700
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Subject: Re: [PATCH v5 3/3] scsi: ufs: sysfs: Make max_number_of_rtt
 read-write
To: Avri Altman <avri.altman@wdc.com>,
 "Martin K . Petersen" <martin.petersen@oracle.com>
Cc: Bean Huo <beanhuo@micron.com>, Peter Wang <peter.wang@mediatek.com>,
 linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20240523125827.818-1-avri.altman@wdc.com>
 <20240523125827.818-4-avri.altman@wdc.com>
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From: Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <20240523125827.818-4-avri.altman@wdc.com>
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On 5/23/24 05:58, Avri Altman wrote:
> +	/* make sure that there are no outstanding requests when rtt is set */
> +	ufshcd_scsi_block_requests(hba);
> +	blk_mq_wait_quiesce_done(&hba->host->tag_set);
> +
> +	ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
> +		QUERY_ATTR_IDN_MAX_NUM_OF_RTT, 0, 0, &rtt);
> +
> +	ufshcd_scsi_unblock_requests(hba);

The above doesn't look correct to me. ufshcd_scsi_block_requests() does
not guarantee that all pending commands have finished by the time it
returns. Please blk_mq_freeze_queue() / blk_mq_unfreeze_queue() instead.

Thanks,

Bart.