Re: Functionality issues in UDF support

[Laszlo Ersek <lersek@redhat.com>]

Jiewen,

On 09/16/17 01:38, Yao, Jiewen wrote:
> Hi Laszlo and Ruiyu
> I can think 1 possible alternative, for your consideration only.
> 
> 1)       Move the feature to OvmfPkg.
> 
> As such, it won't block us at this moment.
> 
> Once the UDF solution has good quality, we can move it back to MdeModulePkg.

the urgent issue is not with the UdfDxe driver; a platform can simply
choose not to include the UdfDxe driver. The problem is that the
UDF-related changes in PartitionDxe have caused a regression in
PartitionDxe, and PartitionDxe is something that all platforms must include.

The feature PCD that I suggested would turn the (currently buggy) UDF
logic in PartitionDxe into a no-op by default.

Thanks
Laszlo


> From: Laszlo Ersek [mailto:lersek@redhat.com]
> Sent: Saturday, September 16, 2017 12:51 AM
> To: Ni, Ruiyu <ruiyu.ni@intel.com>; Paulo Alcantara <pcacjr@zytor.com>
> Cc: Yao, Jiewen <jiewen.yao@intel.com>; Wu, Hao A <hao.a.wu@intel.com>; edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
> Subject: Re: [edk2] Functionality issues in UDF support
> 
> On 09/15/17 18:40, Ni, Ruiyu wrote:
>> Laszlo,
>> Please do not add a PCD for this. Too many PCDs are no good to the project.
> 
> I understand that new MdeModulePkg PCDs are not liked, but what do you
> propose instead? If we simply revert the PartitionDxe changes, then
> people that want to experiment with general UDF support under OVMF won't
> be able to do that at all.
> 
> I'm in the process of adding -D UDF_ENABLE to OvmfPkg, ArmVirtPkg, and
> Nt32Pkg, which would control both the FeaturePCD and the inclusion of
> UdfDxe in the build. If you disagree with the FeaturePCD, I can stop
> working on this, but I don't know what the alternative is. "Fix it
> immediately" is not an alternative; we can't do that. If you want to
> revert the change, it's your prerogative, but that will prevent
> everybody from testing gradual UDF improvements. (No 3rd parties build
> OVMF from any staging branches, so if the feature is only available on a
> staging branch, it might as well not exist, for the outside world.)
> 
> Thanks
> Laszlo
>