Re: [PATCH v2] MinPlatformPkg/TestPointCheckLib: Add return value when OutTable is NULL

["Nate DeSimone" <nathaniel.l.desimone@intel.com>]

Hi Shenglei,

Your explanation makes sense.

Reviewed-by: Nate DeSimone <nathaniel.l.desimone@intel.com>

Thanks,
Nate

-----Original Message-----
From: Zhang, Shenglei <shenglei.zhang@intel.com> 
Sent: Monday, September 16, 2019 7:48 PM
To: Desimone, Nathaniel L <nathaniel.l.desimone@intel.com>; devel@edk2.groups.io
Cc: Kubacki, Michael A <michael.a.kubacki@intel.com>; Chiu, Chasel <chasel.chiu@intel.com>; Gao, Liming <liming.gao@intel.com>
Subject: RE: [PATCH v2] MinPlatformPkg/TestPointCheckLib: Add return value when OutTable is NULL

Hi Nathaniel,

Thanks for your comments and below is my response.

> -----Original Message-----
> From: Desimone, Nathaniel L
> Sent: Tuesday, September 17, 2019 3:25 AM
> To: Zhang, Shenglei <shenglei.zhang@intel.com>; devel@edk2.groups.io
> Cc: Kubacki, Michael A <michael.a.kubacki@intel.com>; Chiu, Chasel 
> <chasel.chiu@intel.com>; Gao, Liming <liming.gao@intel.com>
> Subject: RE: [PATCH v2] MinPlatformPkg/TestPointCheckLib: Add return 
> value when OutTable is NULL
> 
> Hi Shenglei,
> 
> I don't see how this patch is at all related to the previous version of this patch.

What is different from the previous version is that this patch update the copyright year and the "if...else" coding style.

> Also, you are introducing yet another new bug with this patch. 
> Moreover, this bug is unrelated to the previous bug.
> 
> Please take a look at the function TestPointGetAcpi(). With your 
> change added, this function is now broken since Table is a stack 
> variable and it is not being initialized to zero. This function 
> assumes that
> DumpAcpiXsdt()/DumpAcpiRsdt() will do the initialization to zero on 
> it's behalf, you have broken this assumption with your change.

I have taken a look at the function TestPointGetAcpi(). The variable Table is first initialized to NULL by DumpAcpiXsdt()/DumpAcpiRsdt(). The reference code is "*OutTable = NULL"(line 667). And it will be assigned a value next. The reference code is "*OutTable = Table"(line 689).

And with my changes, the stack variable Table(equivalent  to *OutTable in DumpAcpiXsdt/ DumpAcpiRsdt) can still be initialized to NULL or assigned a value. What I did is intended to check the address of "Table", since there is no point to perform operations to "Table" if its address is NULL.

Thanks,
Shenglei

> 
> Both this patch and the previous patch have been made carelessly and I 
> am not impressed.
> 
> Thanks,
> Nate
> 
> -----Original Message-----
> From: Zhang, Shenglei <shenglei.zhang@intel.com>
> Sent: Sunday, September 15, 2019 6:09 PM
> To: devel@edk2.groups.io
> Cc: Kubacki, Michael A <michael.a.kubacki@intel.com>; Chiu, Chasel 
> <chasel.chiu@intel.com>; Desimone, Nathaniel L 
> <nathaniel.l.desimone@intel.com>; Gao, Liming <liming.gao@intel.com>
> Subject: [PATCH v2] MinPlatformPkg/TestPointCheckLib: Add return value 
> when OutTable is NULL
> 
> Currently there is no check for the parameter OutTable.
> So add the logic that return value EFI_INVALID_PARAMETER when the 
> OutTable is NULL.
> 
> Cc: Michael Kubacki <michael.a.kubacki@intel.com>
> Cc: Chasel Chiu <chasel.chiu@intel.com>
> Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
> Cc: Liming Gao <liming.gao@intel.com>
> Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
> ---
> 
> v2:Update the copyright and the if...else statement coding style.
> 
>  .../Test/Library/TestPointCheckLib/DxeCheckAcpi.c           | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git
> a/Platform/Intel/MinPlatformPkg/Test/Library/TestPointCheckLib/DxeChec
> k
> Acpi.c
> b/Platform/Intel/MinPlatformPkg/Test/Library/TestPointCheckLib/DxeChec
> k
> Acpi.c
> index 263781a2..83736bf3 100644
> ---
> a/Platform/Intel/MinPlatformPkg/Test/Library/TestPointCheckLib/DxeChec
> k
> Acpi.c
> +++
> b/Platform/Intel/MinPlatformPkg/Test/Library/TestPointCheckLib/DxeCh
> +++ eckAcpi.c
> @@ -1,6 +1,6 @@
>  /** @file
> 
> -Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2017 - 2019, Intel Corporation. All rights 
> +reserved.<BR>
>  SPDX-License-Identifier: BSD-2-Clause-Patent
> 
>  **/
> @@ -610,6 +610,8 @@ DumpAcpiRsdt (
> 
>    if (OutTable != NULL) {
>      *OutTable = NULL;
> +  } else{
> +    return EFI_INVALID_PARAMETER;
>    }
> 
>    ReturnStatus = EFI_SUCCESS;
> @@ -663,6 +665,8 @@ DumpAcpiXsdt (
> 
>    if (OutTable != NULL) {
>      *OutTable = NULL;
> +  } else{
> +    return EFI_INVALID_PARAMETER;
>    }
> 
>    ReturnStatus = EFI_SUCCESS;
> --
> 2.18.0.windows.1