Re: [PATCH v2 01/22] x86/fpu/xstate: Modify area init helper prototypes to access all the possible areas

["Bae, Chang Seok" <chang.seok.bae@intel.com>]

> On Dec 8, 2020, at 02:12, Borislav Petkov <bp@suse.de> wrote:
> 
> On Thu, Nov 19, 2020 at 03:32:36PM -0800, Chang S. Bae wrote:
> > The xstate infrastructure is not flexible to support dynamic areas in
> > task->fpu.
> 
> task->fpu?

It was considered to be concise to represent, but it looks to be 
unreadable.

> Do you mean the fpu member in struct thread_struct ?

Yes. Will make sure to use this for clarification at fist.

> > Change the fpstate_init() prototype to access task->fpu directly. It
> > treats a null pointer as indicating init_fpstate, as this initial data
> > does not belong to any task.
> 
> What for? Commit messages should state *why* you're doing a change - not
> *what* you're doing. *What* I can more or less see, *why* is harder.

An earlier version had wordy explanations, but it looks too much trimmed
down.

(I suspect this point applicable to PATCH2-4 as well.)

> /me goes and looks forward into the patchset...
> 
> Are you going to need it for stuff like
> 
> 	fpu ? fpu->state_mask : get_init_fpstate_mask()
> 
> ?

Yes, I think that’s one of the cases.

> If so, why don't you write *why* you're doing those changes here?

Will do that.

Thanks,
Chang