linux-kernel - Re: [PATCH v3] scsi: ufs: core: skip UFS clkscale if host asynchronous scan in progress

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <b7b0b907-8f5c-481c-9a68-cb3e20b59cb0@quicinc.com>
Date: Wed, 21 May 2025 16:56:02 +0800
From: Ziqi Chen <quic_ziqichen@...cinc.com>
To: Peter Wang (王信友) <peter.wang@...iatek.com>,
        "beanhuo@...ron.com" <beanhuo@...ron.com>,
        "avri.altman@....com"
	<avri.altman@....com>,
        "quic_rampraka@...cinc.com"
	<quic_rampraka@...cinc.com>,
        "quic_cang@...cinc.com" <quic_cang@...cinc.com>,
        "quic_nguyenb@...cinc.com" <quic_nguyenb@...cinc.com>,
        "quic_nitirawa@...cinc.com" <quic_nitirawa@...cinc.com>,
        "bvanassche@....org"
	<bvanassche@....org>,
        "neil.armstrong@...aro.org"
	<neil.armstrong@...aro.org>,
        "luca.weiss@...rphone.com"
	<luca.weiss@...rphone.com>,
        "konrad.dybcio@....qualcomm.com"
	<konrad.dybcio@....qualcomm.com>,
        "junwoo80.lee@...sung.com"
	<junwoo80.lee@...sung.com>,
        "mani@...nel.org" <mani@...nel.org>,
        "martin.petersen@...cle.com" <martin.petersen@...cle.com>
CC: "linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
        "linux-arm-msm@...r.kernel.org" <linux-arm-msm@...r.kernel.org>,
        "manivannan.sadhasivam@...aro.org" <manivannan.sadhasivam@...aro.org>,
        "alim.akhtar@...sung.com" <alim.akhtar@...sung.com>,
        "James.Bottomley@...senPartnership.com"
	<James.Bottomley@...senPartnership.com>,
        "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v3] scsi: ufs: core: skip UFS clkscale if host
 asynchronous scan in progress



On 5/14/2025 5:05 PM, Peter Wang (王信友) wrote:
> On Wed, 2025-05-14 at 15:25 +0800, Ziqi Chen wrote:
>>
>> Hi Bart,
>>
>> I tried the scan_mutex, from debugging logs, it seems okay for now.
>> I will provide to our internal test team for stability test.
>> And I will try to collect the extra time spent on clock scaling
>> path with applying scan_mutex.
>> If everything is fine, I will update a new version.
>>
>> BRs,
>> Ziqi
>>
>>
>>
> 
> Hi Ziqi,
> 
> Could we enable devfreq when checking if hba->luns_avail equals 1
> in ufshcd_device_configure?
> I think we can use flow to ensure correctness; it doesn't
> necessarily need to be protected by a mutex.
> 
> Thanks
> Peter

Hi Peter,

Thanks for your suggestion, and sorry for the late response—I was out of
office last week.

It looks like checking hba->luns_avail == 1 in ufshcd_device_configure
before enabling devfreq can ensure correctness. But I think the
function name 'ufshcd_device_configure' suggests that enabling devfreq
inside it is not reasonable. That’s another same reason why we moved
ufshcd_devfreq_init() out of ufshcd_add_lus() in this patch.

BRs,
Ziqi

> 
>