Re: [PATCH v5 09/18] x86/sgx: Store struct sgx_encl when allocating new VA pages

["Huang, Kai" <kai.huang@intel.com>]

On Fri, 2023-09-29 at 10:06 -0500, Haitao Huang wrote:
> On Wed, 27 Sep 2023 16:21:19 -0500, Huang, Kai <kai.huang@intel.com> wrote:
> 
> > On Wed, 2023-09-27 at 10:35 -0500, Haitao Huang wrote:
> > > > > +
> > > > > +	/* Possible owner types */
> > > > > +	union {
> > > > > +		struct sgx_encl_page *encl_page;
> > > > > +		struct sgx_encl *encl;
> > > > > +	};
> > > > 
> > > > Sadly for virtual EPC page the owner is set to the 'sgx_vepc'  
> > > instance it
> > > > belongs to.
> > > > 
> > > > Given how sgx_{alloc|free}_epc_page() arbitrarily uses encl_page,>  
> > > perhaps we
> > > > should do below?
> > > > 
> > > >  	union {
> > > >  		struct sgx_encl_page *encl_page;
> > > >  		struct sgx_encl *encl;
> > > >  		struct sgx_vepc *vepc;
> > > >  		void *owner;
> > > >  	};
> > > > 
> > > > And in sgx_{alloc|free}_epc_page() we can use 'owner' instead.
> > > > 
> > > 
> > > As I mentioned in cover letter and change log in 11/18, this series does 
> > > not track virtual EPC.
> > 
> > It's not about how does the cover letter says.  We cannot ignore the  
> > fact that
> > currently virtual EPC uses owner too.
> > 
> > But given the virtual EPC code currently doesn't use the owner, I can  
> > live with
> > not having the 'vepc' member in the union now.
> 
> Ah, I forgot even though we don't use the owner field assigned by vepc, it  
> is still passed into sgx_alloc/free_epc_page().
> 
> Will add back "void* owner" and use it for assignment inside  
> sgx_alloc/free_epc_page().
> 
> 

And also sgx_setup_epc_section().