linux-kernel - Re: [PATCH] coresight: dynamic-replicator: Fix handling of multiple connections

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]

Date:   Tue, 19 May 2020 14:34:03 +0530
From:   Sai Prakash Ranjan <saiprakash.ranjan@...eaurora.org>
To:     Mike Leach <mike.leach@...aro.org>,
        Suzuki K Poulose <suzuki.poulose@....com>,
        Mathieu Poirier <mathieu.poirier@...aro.org>
Cc:     Stephen Boyd <swboyd@...omium.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-arm-msm@...r.kernel.org,
        linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
        Russell King <linux@...linux.org.uk>
Subject: Re: [PATCH] coresight: dynamic-replicator: Fix handling of multiple
 connections

Hi Mike, Suzuki,

On 2020-05-16 15:34, Sai Prakash Ranjan wrote:
> Hi Mike, Suzuki
> 
> [...]
> 
>>> 
>>> Please look at the CoreSight components specification 3.0 (ARM IHI
>>> 0029E) Section B2.1.2 which describes the Unique Component Identifier
>>> (UCI).
>>> As mentioned above this consists of a combination of bits from
>>> multiple registers, including PIDR4.
>>> 
>> 
>> Ok got it now, thanks for clearing the doubt. I will go ahead with
>> this method to identify QCOM impl and post a patch.
>> 
> 
> Looking some more into this, since we have this limitation only on
> specific replicator on very few QCOM SoCs, rather than having a blanket
> workaround for all QCOM, we were thinking it would be better to have
> this workaround based on a firmware property something like
> "qcom,replicator-loses-context" for those replicators with this
> limitation and then set the drvdata->check_idfilter_val based on
> this property.
> 

Sorry for going back and forth on this one, but I think having a 
firmware
property will clearly help us identify the issue on specific SoCs rather 
than
wholesale workaround for all QCOM SoCs. For now, I will post a patch 
based on
the property "qcom,replicator-loses-context", please feel free to yell 
at me
if this is completely wrong and we can discuss it further in that patch.

Thanks,
Sai

-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a 
member
of Code Aurora Forum, hosted by The Linux Foundation