Re: [PATCH V5] MdeModulePkg/DxeCore: Fixed Interface returned by CoreOpenProtocol

[Laszlo Ersek <lersek@redhat.com>]

On 06/28/17 20:08, Amit kumar wrote:
> Try this; just a quick thing
> 
> 
> 
> EFI_STATUS
> EFIAPI
> UefiMain (
>   IN EFI_HANDLE        ImageHandle,
>   IN EFI_SYSTEM_TABLE  *SystemTable
>   )
> {
>     EFI_STATUS Status;
> 
> ConvertHandleIndexToHandle((UINTN)Intermediate);
> 
> 
> gBS->DisconnectController (
> 
>        ConvertHandleIndexToHandle (175),
> 
>        ConvertHandleIndexToHandle (176),
>        NULL);
> 
> return (Status); }

Sorry, what is this program supposed to do, and what are the (likely
undesirable) symptoms that you are witnessing (... presumably as a
consequence of the v5 patch below)?

Thanks
Laszlo

> 
> 
> ________________________________
> From: edk2-devel <edk2-devel-bounces@lists.01.org> on behalf of Laszlo Ersek <lersek@redhat.com>
> Sent: Wednesday, June 28, 2017 7:43:45 PM
> To: Star Zeng; edk2-devel@lists.01.org
> Cc: Michael D Kinney; Gabriel Somlo; Liming Gao
> Subject: Re: [edk2] [PATCH V5] MdeModulePkg/DxeCore: Fixed Interface returned by CoreOpenProtocol
> 
> On 06/28/17 15:22, Star Zeng wrote:
>> From: Amit Kumar <amit.ak@samsung.com>
>>
>> Change since v4: Revise the patch based on V4 sent by Amit Kumar
>> 1) Only return the corresponding protocol interface in *Interface
>> if the return status is EFI_SUCCESS or EFI_ALREADY_STARTED.
>> 2) Interface is returned unmodified for all error conditions except
>> EFI_UNSUPPORTED and EFI_ALREADY_STARTED, NULL will be returned in
>> *Interface when EFI_UNSUPPORTED and Attributes is not
>> EFI_OPEN_PROTOCOL_TEST_PROTOCOL, the protocol interface will be
>> returned in *Interface when EFI_ALREADY_STARTED.
>>
>> Change since v3:
>> 1) Fixed issue when Attributes = EFI_OPEN_PROTOCOL_TEST_PROTOCOL
>> and Inteface = NULL case. [Reported by:star.zeng at intel.com]
>>
>> Change Since v2:
>> 1) Modified to use EFI_ERROR to get status code
>>
>> Change since v1:
>> 1) Fixed typo protocal to protocol
>> 2) Fixed coding style
>>
>> Cc: Laszlo Ersek <lersek@redhat.com>
>> Cc: Amit Kumar <amit.ak@samsung.com>
>> Cc: Michael D Kinney <michael.d.kinney@intel.com>
>> Cc: Liming Gao <liming.gao@intel.com>
>> Cc: Gabriel Somlo <gsomlo@gmail.com>
>> Contributed-under: TianoCore Contribution Agreement 1.0
>> Signed-off-by: Amit Kumar <amit.ak@samsung.com>
>> Signed-off-by: Star Zeng <star.zeng@intel.com>
>> ---
>>  MdeModulePkg/Core/Dxe/Hand/Handle.c | 36 +++++++++++++++++++++++-------------
>>  1 file changed, 23 insertions(+), 13 deletions(-)
> 
> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
> Tested-by: Laszlo Ersek <lersek@redhat.com>
> 
> Thanks!
> Laszlo
> 
>> diff --git a/MdeModulePkg/Core/Dxe/Hand/Handle.c b/MdeModulePkg/Core/Dxe/Hand/Handle.c
>> index 59b89148c8f0..3862a3876f4a 100644
>> --- a/MdeModulePkg/Core/Dxe/Hand/Handle.c
>> +++ b/MdeModulePkg/Core/Dxe/Hand/Handle.c
>> @@ -1006,12 +1006,8 @@ CoreOpenProtocol (
>>    //
>>    // Check for invalid Interface
>>    //
>> -  if (Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) {
>> -    if (Interface == NULL) {
>> -      return EFI_INVALID_PARAMETER;
>> -    } else {
>> -      *Interface = NULL;
>> -    }
>> +  if ((Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) && (Interface == NULL)) {
>> +    return EFI_INVALID_PARAMETER;
>>    }
>>
>>    //
>> @@ -1078,12 +1074,6 @@ CoreOpenProtocol (
>>      goto Done;
>>    }
>>
>> -  //
>> -  // This is the protocol interface entry for this protocol
>> -  //
>> -  if (Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) {
>> -    *Interface = Prot->Interface;
>> -  }
>>    Status = EFI_SUCCESS;
>>
>>    ByDriver        = FALSE;
>> @@ -1177,8 +1167,28 @@ CoreOpenProtocol (
>>    }
>>
>>  Done:
>> +
>> +  if (Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) {
>> +    //
>> +    // Keep Interface unmodified in case of any Error
>> +    // except EFI_ALREADY_STARTED and EFI_UNSUPPORTED.
>> +    //
>> +    if (!EFI_ERROR (Status) || Status == EFI_ALREADY_STARTED) {
>> +      //
>> +      // EFI_ALREADY_STARTED is not an error for bus driver.
>> +      // Return the corresponding protocol interface.
>> +      //
>> +      *Interface = Prot->Interface;
>> +    } else if (Status == EFI_UNSUPPORTED) {
>> +      //
>> +      // Return NULL Interface if Unsupported Protocol.
>> +      //
>> +      *Interface = NULL;
>> +    }
>> +  }
>> +
>>    //
>> -  // Done. Release the database lock are return
>> +  // Done. Release the database lock and return
>>    //
>>    CoreReleaseProtocolLock ();
>>    return Status;
>>
> 
> _______________________________________________
> edk2-devel mailing list
> edk2-devel@lists.01.org
> https://lists.01.org/mailman/listinfo/edk2-devel
>