Re: [Tee-dev] [RFC v2 2/6] tee: enable support to register kernel memory

From: Sumit Garg
Date: Fri Aug 09 2019 - 01:36:43 EST


On Fri, 9 Aug 2019 at 03:57, Stuart Yoder <stuart.yoder@xxxxxxx> wrote:
>
>
>
> On 7/30/19 7:23 AM, Sumit Garg wrote:
>
> > @@ -264,7 +266,17 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
> > goto err;
> > }
> >
> > - rc = get_user_pages_fast(start, num_pages, FOLL_WRITE, shm->pages);
> > + if (flags & TEE_SHM_USER_MAPPED) {
> > + rc = get_user_pages_fast(start, num_pages, FOLL_WRITE,
> > + shm->pages);
> > + } else {
> > + const struct kvec kiov = {
> > + .iov_base = (void *)start,
> > + .iov_len = PAGE_SIZE
> > + };
> > +
> > + rc = get_kernel_pages(&kiov, num_pages, 0, shm->pages);
>
> Passing a single kvec struct is temporary I assume? Because as currently
> written this will only work with num_pages==1.
>

Ah, thanks Stuart for pointing this out. It should rather be an array
of kvec struct. Will fix it in next version.

-Sumit

> Stuart