Re: [PATCH v4] kselftests/damon: add support for cases where debugfs cannot be read

[Shuah Khan <skhan@linuxfoundation.org>]

On 6/25/22 2:03 PM, SeongJae Park wrote:
> Hi Gautam,
> 
> On Sun, 26 Jun 2022 01:22:45 +0530 Gautam <gautammenghani201@gmail.com> wrote:
> 
>> The kernel is in lockdown mode when secureboot is enabled and hence
>> debugfs cannot be used. Add support for this and other general cases
>> where debugfs cannot be read and communicate the same to the user before
>> running tests.
>>
>> Signed-off-by: Gautam <gautammenghani201@gmail.com>
> 
> Reviewed-by: SeongJae Park <sj@kernel.org>
> 
> 
> Thanks,
> SJ
> 
>> ---
>> Changes in v2:
>> 1. Modify the error message to account for general cases.
>> 2. Change the return code so that the test is skipped.
>>
>> Changes in v3:
>> 1. Change the name of variable holding the error message.
>>
>> Changes in v4:
>> 1. Correct the mode of the source file.
>>
>>   tools/testing/selftests/damon/_chk_dependency.sh | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>>
>> diff --git a/tools/testing/selftests/damon/_chk_dependency.sh b/tools/testing/selftests/damon/_chk_dependency.sh
>> index 0189db81550b..0328ac0b5a5e 100644
>> --- a/tools/testing/selftests/damon/_chk_dependency.sh
>> +++ b/tools/testing/selftests/damon/_chk_dependency.sh
>> @@ -26,3 +26,13 @@ do
>>   		exit 1
>>   	fi
>>   done
>> +
>> +permission_error="Operation not permitted"
>> +for f in attrs target_ids monitor_on
>> +do
>> +	status=$( cat "$DBGFS/$f" 2>&1 )
>> +	if [ "${status#*$permission_error}" != "$status" ]; then
>> +		echo "Permission for reading $DBGFS/$f denied; maybe secureboot enabled?"

btw - does this run as a regular user or does it need root privilege?
If so add a test for that and skip with a message.
>> +		exit $ksft_skip
>> +	fi
>> +done
>> -- 
>> 2.36.1
>
thanks,
-- Shuah