Re: [edk2-devel] [PATCH v1 1/1] NetworkPkg/SnpDxe: Remove ExitBootServices event

["Laszlo Ersek" <lersek@redhat.com>]

On 10/11/19 02:14, Fu, Siyuan wrote:
>> -----Original Message-----
>> From: Laszlo Ersek <lersek@redhat.com>
>> Sent: 2019年10月11日 0:06
>> To: Fu, Siyuan <siyuan.fu@intel.com>; devel@edk2.groups.io; Rabeda,
>> Maciej <maciej.rabeda@intel.com>
>> Cc: Wu, Jiaxin <jiaxin.wu@intel.com>
>> Subject: Re: [edk2-devel] [PATCH v1 1/1] NetworkPkg/SnpDxe: Remove
>> ExitBootServices event
>>
>> On 10/10/19 11:29, Fu, Siyuan wrote:
>>>> -----Original Message-----
>>>> From: Laszlo Ersek <lersek@redhat.com>
>>>> Sent: 2019年10月10日 16:06
>>>> To: Fu, Siyuan <siyuan.fu@intel.com>; devel@edk2.groups.io; Rabeda,
>>>> Maciej <maciej.rabeda@intel.com>
>>>> Cc: Wu, Jiaxin <jiaxin.wu@intel.com>
>>>> Subject: Re: [edk2-devel] [PATCH v1 1/1] NetworkPkg/SnpDxe: Remove
>>>> ExitBootServices event
>>>>
>>>> On 10/10/19 05:32, Fu, Siyuan wrote:
>>>>> Hi, Maciej
>>>>>
>>>>> Considering that this patch has to co-work with corresponding UNDI
>> device
>>>> driver
>>>>> bug fix, in order to avoid potential compatibility problem, please add a
>> PCD
>>>> to
>>>>> NetworkPkg for this fix, and set the default value to disable state (no
>>>> behavior
>>>>>  change). The platform which need this fix could set the PCD to enable in
>>>> its
>>>>> platform DSC.
>>>>
>>>> Should the new PCD go into "NetworkPkg/NetworkPcds.dsc.inc", and be
>>>> gated with a new build flag defined in
>> "NetworkPkg/NetworkDefines.dsc.inc"?
>>>
>>> Currently not all the network package PCDs are listed in the
>> NetworkPcds.dsc.inc,
>>> But I do not oppose it if you think this PCD should be controlled by a build
>> flag.
>>
>> I mainly asked from a consistency point of view.
>>
>> The inclusion of SnpDxe is already controlled by NETWORK_SNP_ENABLE, at
>> least in platforms that utilize the NetworkPkg *.inc files. And the PCD
>> in question would control the behavior of SnpDxe at ExitBootServices(),
>> if I understand correctly.
>>
>> This is similar to NETWORK_HTTP_BOOT_ENABLE and
>> NETWORK_ALLOW_HTTP_CONNECTIONS:
>> - The former includes HttpDxe and HttpBootDxe (and some other drivers).
>> - The latter controls PcdAllowHttpConnections, which is consumed by
>> HttpDxe and HttpBootDxe.
>>
>> I don't feel too strongly about it, I just thought it worth raising.
> 
> It's not an existing "consistency" in current network package. The current macros
> are mostly used for control more high level feature enable/disable, not such kind
> of bug fix,
> For example, NETWORK_ISCSI_ENABLE includes IScsiDxe driver, while 
> PcdIScsiAIPNetworkBootPolicy is consumed by IScsiDriver, but not controlled by
> a macro. And also other PXE, DHCP and PXE related PCDs.

Good point!

So, I'm fine if the new feature PCD is not exposed with a build flag.

Thanks
Laszlo