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From:   Sumit Garg <sumit.garg@linaro.org>
Date:   Fri, 9 Aug 2019 11:06:24 +0530
Message-ID: <CAFA6WYPUEUVJqk9E2F6z9oBW3VpC+xeqqpY4YrU9KPL1s0DTyA@mail.gmail.com>
Subject: Re: [Tee-dev] [RFC v2 2/6] tee: enable support to register kernel memory
To:     Stuart Yoder <stuart.yoder@arm.com>
Cc:     keyrings@vger.kernel.org, linux-integrity@vger.kernel.org,
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On Fri, 9 Aug 2019 at 03:57, Stuart Yoder <stuart.yoder@arm.com> 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