Messages in this thread | | | From | Sumit Garg <> | Date | Wed, 17 May 2023 13:22:51 +0530 | Subject | Re: [PATCH] tee: add FOLL_LONGTERM for CMA case when alloc shm |
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On Wed, 17 May 2023 at 13:04, Christoph Hellwig <hch@infradead.org> wrote: > > > + u32 page_flag = FOLL_WRITE; > > > > if (!tee_device_get(teedev)) > > return ERR_PTR(-EINVAL); > > @@ -255,9 +256,11 @@ register_shm_helper(struct tee_context *ctx, unsigned long addr, > > ret = ERR_PTR(-ENOMEM); > > goto err_free_shm; > > } > > - > > +#if IS_ENABLED(CONFIG_CMA) > > + page_flag |= FOLL_LONGTERM; > > +#endif > > if (flags & TEE_SHM_USER_MAPPED) > > If this mapping is long live it should always use FOLL_LONGTERM.
It depends on the userspace application needs. However, I think it should be safe to use FOLL_LONGTERM by default to serve cases like secure media playback.
> > The ifdef does not make sense.
Agree.
-Sumit
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