Re: [PATCH] coresight: trbe: Move check for kernelspace unmapped at EL0 to probe

[Anshuman Khandual]

On 2/3/22 5:34 PM, Sudeep Holla wrote:
>> Could you please add a similar comment like SPE driver regarding how
>> the TRBE buffer will be inaccessible, if kernel gets unmapped at EL0
>> and trace capture will terminate.
>>
> Sure I can add that. But if the device probe fails, will you be able to even
> start the trace capture, sorry I didn't get what you mean by "trace capture
> will terminate". I assume it must be "trace capture is not possible or not
> allowed" IIUC.

I guess the comment should be framed like - what might happen if the following
code block which checks for arm64_kernel_unmapped_at_el0() is not present. If
TRBE gets enabled along with kernel unmapping at EL0 supported, trace capture
will terminate.