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Date:   Fri, 20 Nov 2020 11:10:51 +0530
From:   Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
To:     Suzuki K Poulose <suzuki.poulose@arm.com>
Cc:     linux-arm-kernel@lists.infradead.org, mathieu.poirier@linaro.org,
        mike.leach@linaro.org, linux-kernel@vger.kernel.org,
        anshuman.khandual@arm.com, jonathan.zhouwen@huawei.com,
        coresight@lists.linaro.org, Tingwei Zhang <tingwei@codeaurora.org>
Subject: Re: [PATCH v4 02/25] coresight: etm4x: Skip accessing TRCPDCR in
 save/restore
In-Reply-To: <20201119164547.2982871-3-suzuki.poulose@arm.com>
References: <20201119164547.2982871-1-suzuki.poulose@arm.com>
 <20201119164547.2982871-3-suzuki.poulose@arm.com>
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Hi Suzuki,

On 2020-11-19 22:15, 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.
> 

Thanks for the patch, I did test at the time if these accesses
in save and restore cause any hang and they do not. But
this patch doesn't leave anything to chances, so its good.

Reviewed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>

Thanks,
Sai

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