Re: [PATCH] MdeModulePkg/Variable: add debug logs in VariableServiceSetVariable

["Zeng, Star" <star.zeng@intel.com>]

On 2018/11/20 19:17, Laszlo Ersek wrote:
> On 11/20/18 11:38, Vijayenthiran Subramaniam wrote:
>> Print debug messages if size of the VariableName plus DataSize exceeds
>> Max(Auth|Voltaile)VariableSize bytes. The messages will be useful if any
>> platform specific value of Max(Auth|Voltaile)VariableSize PCDs have to
>> be changed.
>>
>> Cc: Star Zeng <star.zeng@intel.com>
>> Cc: Jian J Wang <jian.j.wang@intel.com>
>> Cc: Ruiyu Ni <ruiyu.ni@intel.com>
>> Contributed-under: TianoCore Contribution Agreement 1.1
>> Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>
>> ---
>>   MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c | 6 ++++++
>>   1 file changed, 6 insertions(+)
>>
>> diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
>> index 8e8db71bd201..db54fa4412c0 100644
>> --- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
>> +++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
>> @@ -3234,14 +3234,20 @@ VariableServiceSetVariable (
>>       //
>>       if ((Attributes & VARIABLE_ATTRIBUTE_AT_AW) != 0) {
>>         if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxAuthVariableSize - GetVariableHeaderSize ()) {
>> +        DEBUG ((DEBUG_ERROR, "%a: Size of (%s) variable + DataSize exceeds MaxAuthVariableSize.\n",
>> +          __FUNCTION__, VariableName));
>>           return EFI_INVALID_PARAMETER;
>>         }
>>       } else if ((Attributes & EFI_VARIABLE_NON_VOLATILE) != 0) {
>>         if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxVariableSize - GetVariableHeaderSize ()) {
>> +        DEBUG ((DEBUG_ERROR, "%a: Size of (%s) variable + DataSize exceeds MaxVariableSize.\n",
>> +          __FUNCTION__, VariableName));
>>           return EFI_INVALID_PARAMETER;
>>         }
>>       } else {
>>         if (StrSize (VariableName) + PayloadSize > mVariableModuleGlobal->MaxVolatileVariableSize - GetVariableHeaderSize ()) {
>> +        DEBUG ((DEBUG_ERROR, "%a: Size of (%s) variable + DataSize exceeds MaxVolatileVariableSize.\n",
>> +          __FUNCTION__, VariableName));
>>           return EFI_INVALID_PARAMETER;
>>         }
>>       }
>>
> 
> You could make this more useful as well -- again, *if* the package
> maintainers agree with the new log messages --; namely, the vendor GUID,
> DataSize, and the limit in question should / could all be logged.

I agree to add these debug messages. I also think Laszlo's suggestion is 
good.

So, how about having the debug message like below?

         DEBUG ((
           DEBUG_ERROR,
           "%a: %s:%g\n",
           __FUNCTION__,
           VariableName,
           VendorGuid
           ));
         DEBUG ((
           DEBUG_ERROR,
           "  NameSize(0x%x) + PayloadSize(0x%x) > 
MaxAuthVariableSize(0x%x) - HeaderSize(0x%x)\n",
           StrSize (VariableName),
           PayloadSize,
           mVariableModuleGlobal->MaxAuthVariableSize,
           GetVariableHeaderSize ()
           ));

Thanks,
Star

> 
> Thanks
> Laszlo
>