[PATCH v2 5/5] powerpc/configs: Disable SCOM_DEBUGFS in powernv_defconfig

[Andrew Donnellan]

On 9/5/19 3:37 pm, Nicholas Piggin wrote:
> Andrew Donnellan's on May 9, 2019 3:11 pm:
>> SCOM_DEBUGFS is really not needed for anything other than low-level
>> hardware debugging.
>>
>> opal-prd uses its own interface (/dev/prd) for SCOM access, so it doesn't
>> need SCOM_DEBUGFS.
>>
>> At some point in the future we'll introduce a debug config fragment where
>> this can go instead.
> 
> That doesn't really explain why you want to disable it. It is useful
> for low level hardware debugging, I added it.
> 
> obscurity^Wsecurity?

Mostly just a general feeling that it's not something we need to have by 
default. Security-wise, PRD still provides SCOM access, though we are 
going to look at how we can further lock that down. Shrinks the build by 
only a few kilobytes...

mpe said he's planning on adding a debug.config where we can shift stuff 
like this, and if/when we do that I would like to see this moved there, 
but perhaps this patch can wait until then. I'll let mpe decide.


Andrew


> 
>>
>> Signed-off-by: Andrew Donnellan <ajd at linux.ibm.com>
>> ---
>> v1->v2:
>> - new patch
>> ---
>>   arch/powerpc/configs/powernv_defconfig | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/configs/powernv_defconfig b/arch/powerpc/configs/powernv_defconfig
>> index ef2ef98d3f28..d5a6608cb2e0 100644
>> --- a/arch/powerpc/configs/powernv_defconfig
>> +++ b/arch/powerpc/configs/powernv_defconfig
>> @@ -38,7 +38,7 @@ CONFIG_MODULE_UNLOAD=y
>>   CONFIG_MODVERSIONS=y
>>   CONFIG_MODULE_SRCVERSION_ALL=y
>>   CONFIG_PARTITION_ADVANCED=y
>> -CONFIG_SCOM_DEBUGFS=y
>> +# CONFIG_SCOM_DEBUGFS is not set
>>   CONFIG_OPAL_PRD=y
>>   CONFIG_PPC_MEMTRACE=y
>>   # CONFIG_PPC_PSERIES is not set
>> -- 
>> 2.20.1
>>
>>
> 

-- 
Andrew Donnellan              OzLabs, ADL Canberra
ajd at linux.ibm.com             IBM Australia Limited