Re: [PATCH v7 1/3] x86/sgx: Rename the owner field of struct sgx_epc_page as encl_owner

[Zhiquan Li <zhiquan1.li@intel.com>]

On 2022/9/1 11:36, Huang, Kai wrote:
> On Thu, 2022-09-01 at 08:35 +0800, Zhiquan Li wrote:
>> In order to avoid unnecessary casting, rename the 'owner' field of
>> struct sgx_epc_page as 'encl_owner', and update all of references.
> This changelog itself doesn't explain _why_ renaming 'owner' to 'encl_owner' can
> avoid the explicit casting.  In fact, the reason is that you will use a 'union'
> to separate the use of 'owner' of the EPC page (between SGX driver and virtual
> EPC).  The rename is just to make the name more clear, but cannot really avoid
> casting.
> 
> So I think there should be more sentences to explain here, such as "in order to
> send SIGBUS to userspace hypervisor to allow it to inject #MC to guest, use
> virtual EPC page's owner to be the userspace virtual address of the EPC page",
> and after those you can say something like "in order to avoid casting, use a
> union to separate the use of owner for SGX driver EPC page and virtual EPC page.
> And rename owner of SGX driver EPC page to 'encl_owner' to be more specific",
> etc.
> 
> That being said, I guess you can just merge this patch with your second patch,
> which actually introduces the 'union' and uses the owner for virtual EPC page.
> And in changelog you explain everything above to justify the patch.
> 
> Does this make sense?

Thanks for your review and sentences, Kai!

Hi Jarkko,

Do you agree Kai's proposal? That is, merging patch 01 (just rename, no
functional changes) and patch 02 (introduce a union and utilize the
'vepc_vaddr' field) into one.

- If yes, I'll do it like Kai said.
- If not, I'll just enrich the commit message of patch 01 and keep it
separately.

Best Regards,
Zhiquan

> 
>> Signed-off-by: Zhiquan Li <zhiquan1.li@intel.com>
>>
>> ---
>> Changes since V6:
>> - Revise the commit message suggested by Jarkko.
>>   Link: https://lore.kernel.org/linux-sgx/20220826160503.1576966-1-zhiquan1.li@intel.com/T/#mb201506ed06932438c82d48915cd4ceae9745bc2
>> ---