Re: [PATCH v4 02/25] coresight: etm4x: Skip accessing TRCPDCR in save/restore

From: Suzuki K Poulose
Date: Mon Nov 30 2020 - 04:39:05 EST


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