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Subject: Re: [PATCH v4 02/25] coresight: etm4x: Skip accessing TRCPDCR in
 save/restore
To:     Mathieu Poirier <mathieu.poirier@linaro.org>
Cc:     linux-arm-kernel@lists.infradead.org, mike.leach@linaro.org,
        linux-kernel@vger.kernel.org, anshuman.khandual@arm.com,
        jonathan.zhouwen@huawei.com, coresight@lists.linaro.org,
        Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>,
        Tingwei Zhang <tingwei@codeaurora.org>
References: <20201119164547.2982871-1-suzuki.poulose@arm.com>
 <20201119164547.2982871-3-suzuki.poulose@arm.com>
 <20201127185522.GB1092947@xps15>
From:   Suzuki K Poulose <suzuki.poulose@arm.com>
Message-ID: <136f420d-7848-3ba3-fbb0-9f7edee1377b@arm.com>
Date:   Mon, 30 Nov 2020 09:37:56 +0000
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On 11/27/20 6:55 PM, Mathieu Poirier wrote:
> On Thu, Nov 19, 2020 at 04:45:24PM +0000, Suzuki K Poulose wrote:
>> When the ETM is affected by Qualcomm errata, modifying the
>> TRCPDCR could cause the system hang. Even though this is
>> taken care of during enable/disable ETM, the ETM state
>> save/restore could still access the TRCPDCR. Make sure
>> we skip the access during the save/restore.
>>
>> Found by code inspection.
>>
>> Fixes: commit 02510a5aa78df45 ("coresight: etm4x: Add support to skip trace unit power up")
> 
> https://elixir.bootlin.com/linux/v5.10-rc5/source/Documentation/process/submitting-patches.rst#L121

Thanks, I will remove the "commit".

Suzuki