Re: [PATCH v1 1/3] scsi: ufs: add write booster feature support

From: Steev Klimaszewski <steev@kali.org>
To: Rob Clark <robdclark@gmail.com>,
	Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Avri Altman <Avri.Altman@wdc.com>,
	Asutosh Das <asutoshd@codeaurora.org>,
	"cang@codeaurora.org" <cang@codeaurora.org>,
	"martin.petersen@oracle.com" <martin.petersen@oracle.com>,
	"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>,
	Subhash Jadavani <subhashj@codeaurora.org>,
	Alim Akhtar <alim.akhtar@samsung.com>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	Bean Huo <beanhuo@micron.com>,
	Stanley Chu <stanley.chu@mediatek.com>,
	Tomas Winkler <tomas.winkler@intel.com>,
	Colin Ian King <colin.king@canonical.com>,
	Bart Van Assche <bvanassche@acm.org>,
	open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1 1/3] scsi: ufs: add write booster feature support
Date: Sun, 21 Jun 2020 12:50:27 -0500	[thread overview]
Message-ID: <ba3873e3-75e0-a55f-6a93-d7d8df4da0e9@kali.org> (raw)
In-Reply-To: <CAF6AEGuG3XAqN_sedxk9GRm_9yK+a4OH56CZPmbHx+SW-FNVPQ@mail.gmail.com>


On 6/21/20 11:50 AM, Rob Clark wrote:
> This looks like a device issue to be taken with the flash vendor:
>> There's no way for a end-user to file a bug report with the flash vendor
>> on a device bought from an OEM and even if they would accept the bug
>> report they wouldn't re-provision the flash in an shipped device.
>>
>> So you will have to work around this in the driver.
> oh, ugg.. well I think these msgs from dmesg identify the part if we
> end up needing to use a denylist:
>
> scsi 0:0:0:49488: Well-known LUN    SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
> scsi 0:0:0:49476: Well-known LUN    SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
> scsi 0:0:0:49456: Well-known LUN    SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
> scsi 0:0:0:0: Direct-Access     SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
> scsi 0:0:0:1: Direct-Access     SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
> sd 0:0:0:0: [sda] 29765632 4096-byte logical blocks: (122 GB/114 GiB)
> sd 0:0:0:0: [sda] Write Protect is off
> sd 0:0:0:0: [sda] Mode Sense: 00 32 00 10
> sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports
> DPO and FUA
> sd 0:0:0:0: [sda] Optimal transfer size 786432 bytes
> scsi 0:0:0:2: Direct-Access     SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
> scsi 0:0:0:3: Direct-Access     SKhynix  H28S8Q302CMR     A102 PQ: 0 ANSI: 6
>
>
> (otoh I guess the driver could just notice that writeboost keeps
> failing and stop trying to use it)
>
> BR,
> -R


FWIW, I see this on my c630 as well, but my LUN shows up as


scsi 0:0:0:49488: Well-known LUN    SAMSUNG  KLUDG4U1EA-B0C1   0500 PQ:
0 ANSI: 6