linux-kernel - Re: [PATCH v8 00/29] Rework the trip points creation

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

Message-ID: <851008bf-145d-224c-87a8-cb6ec1e9addb@linaro.org>
Date:   Wed, 5 Oct 2022 14:37:14 +0200
From:   Daniel Lezcano <daniel.lezcano@...aro.org>
To:     Marek Szyprowski <m.szyprowski@...sung.com>
Cc:     linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        rui.zhang@...el.com,
        Broadcom Kernel Team <bcm-kernel-feedback-list@...adcom.com>,
        Support Opensource <support.opensource@...semi.com>,
        Pengutronix Kernel Team <kernel@...gutronix.de>,
        NXP Linux Team <linux-imx@....com>,
        Andy Gross <agross@...nel.org>,
        Bartlomiej Zolnierkiewicz <bzolnier@...il.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>,
        Alim Akhtar <alim.akhtar@...sung.com>, netdev@...r.kernel.org,
        platform-driver-x86@...r.kernel.org,
        linux-rpi-kernel@...ts.infradead.org,
        linux-arm-kernel@...ts.infradead.org,
        linux-arm-msm@...r.kernel.org, linux-renesas-soc@...r.kernel.org,
        linux-samsung-soc@...r.kernel.org, linux-tegra@...r.kernel.org,
        linux-omap@...r.kernel.org, rafael@...nel.org
Subject: Re: [PATCH v8 00/29] Rework the trip points creation


Hi Marek,

On 03/10/2022 23:18, Daniel Lezcano wrote:

[ ... ]

>> I've tested this v8 patchset after fixing the issue with Exynos TMU with
>> https://lore.kernel.org/all/20221003132943.1383065-1-daniel.lezcano@linaro.org/ 
>>
>> patch and I got the following lockdep warning on all Exynos-based boards:
>>
>>
>> ======================================================
>> WARNING: possible circular locking dependency detected
>> 6.0.0-rc1-00083-ge5c9d117223e #12945 Not tainted
>> ------------------------------------------------------
>> swapper/0/1 is trying to acquire lock:
>> c1ce66b0 (&data->lock#2){+.+.}-{3:3}, at: exynos_get_temp+0x3c/0xc8
>>
>> but task is already holding lock:
>> c2979b94 (&tz->lock){+.+.}-{3:3}, at:
>> thermal_zone_device_update.part.0+0x3c/0x528
>>
>> which lock already depends on the new lock.
> 
> I'm wondering if the problem is not already there and related to 
> data->lock ...
> 
> Doesn't the thermal zone lock already prevent racy access to the data 
> structure?
> 
> Another question: if the sensor clock is disabled after reading it, how 
> does the hardware update the temperature and detect the programed 
> threshold is crossed?

just a gentle ping, as the fix will depend on your answer ;)

Thanks

   -- D.

[ ... ]


-- 
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog