Include <linux/uaccess.h> to avoid the warning:
drivers/tee/tee_shm.c: In function 'tee_shm_register':
>> drivers/tee/tee_shm.c:242:14: error: implicit declaration of function 'access_ok' [-Werror=implicit-function-declaration]
242 | if (!access_ok((void __user *)addr, length))
| ^~~~~~~~~
cc1: some warnings being treated as errors
Fixes: 573ae4f13f ("tee: add overflow check in register_shm_helper()")
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
With special lengths supplied by user space, register_shm_helper() has
an integer overflow when calculating the number of pages covered by a
supplied user space memory region.
This causes internal_get_user_pages_fast() a helper function of
pin_user_pages_fast() to do a NULL pointer dereference:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
Modules linked in:
CPU: 1 PID: 173 Comm: optee_example_a Not tainted 5.19.0 #11
Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
pc : internal_get_user_pages_fast+0x474/0xa80
Call trace:
internal_get_user_pages_fast+0x474/0xa80
pin_user_pages_fast+0x24/0x4c
register_shm_helper+0x194/0x330
tee_shm_register_user_buf+0x78/0x120
tee_ioctl+0xd0/0x11a0
__arm64_sys_ioctl+0xa8/0xec
invoke_syscall+0x48/0x114
Fix this by adding an an explicit call to access_ok() in
tee_shm_register_user_buf() to catch an invalid user space address
early.
Fixes: 033ddf12bc ("tee: add register user memory")
Cc: stable@vger.kernel.org
Reported-by: Nimish Mishra <neelam.nimish@gmail.com>
Reported-by: Anirban Chakraborty <ch.anirban00727@gmail.com>
Reported-by: Debdeep Mukhopadhyay <debdeep.mukhopadhyay@gmail.com>
Suggested-by: Jerome Forissier <jerome.forissier@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should not need to index into SHMs based on absolute VA/PA.
These functions are not used and this kind of usage should not be
encouraged anyway. Remove these functions.
Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
In some low-memory devices, it's hard to aquire large-orders pages,
this patch allowed user using scatter pages to register shm.
Signed-off-by: Phil Chang <phil.chang@mediatek.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Removes the redundant TEE_SHM_DMA_BUF, TEE_SHM_EXT_DMA_BUF,
TEE_SHM_MAPPED and TEE_SHM_KERNEL_MAPPED flags.
TEE_SHM_REGISTER is renamed to TEE_SHM_DYNAMIC in order to better
match its usage.
Assigns new values to the remaining flags to void gaps.
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
tee_shm_register() is replaced by the previously introduced functions
tee_shm_register_user_buf() and tee_shm_register_kernel_buf().
Since there are not external callers left we can remove tee_shm_register()
and refactor the remains.
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Adds the two new functions tee_shm_register_user_buf() and
tee_shm_register_kernel_buf() which should be used instead of the old
tee_shm_register().
This avoids having the caller supplying the flags parameter which
exposes a bit more than desired of the internals of the TEE subsystem.
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
tee_shm_alloc() is replaced by three new functions,
tee_shm_alloc_user_buf() - for user mode allocations, replacing passing
the flags TEE_SHM_MAPPED | TEE_SHM_DMA_BUF
tee_shm_alloc_kernel_buf() - for kernel mode allocations, slightly
optimized compared to using the flags TEE_SHM_MAPPED | TEE_SHM_DMA_BUF.
tee_shm_alloc_priv_buf() - primarily for TEE driver internal use.
This also makes the interface easier to use as we can get rid of the
somewhat hard to use flags parameter.
The TEE subsystem and the TEE drivers are updated to use the new
functions instead.
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Replaces the shared memory pool based on two pools with a single pool.
The alloc() function pointer in struct tee_shm_pool_ops gets another
parameter, align. This makes it possible to make less than page aligned
allocations from the optional reserved shared memory pool while still
making user space allocations page aligned. With in practice unchanged
behaviour using only a single pool for bookkeeping.
The allocation algorithm in the static OP-TEE shared memory pool is
changed from best-fit to first-fit since only the latter supports an
alignment parameter. The best-fit algorithm was previously the default
choice and not a conscious one.
The optee and amdtee drivers are updated as needed to work with this
changed pool handling.
This also removes OPTEE_SHM_NUM_PRIV_PAGES which becomes obsolete with
this change as the private pages can be mixed with the payload pages.
The OP-TEE driver changes minimum alignment for argument struct from 8
bytes to 512 bytes. A typical OP-TEE private shm allocation is 224 bytes
(argument struct with 6 parameters, needed for open session). So with an
alignment of 512 well waste a bit more than 50%. Before this we had a
single page reserved for this so worst case usage compared to that would
be 3 pages instead of 1 page. However, this worst case only occurs if
there is a high pressure from multiple threads on secure world. All in
all this should scale up and down better than fixed boundaries.
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Adds a new function tee_shm_alloc_user_buf() for user mode allocations,
replacing passing the flags TEE_SHM_MAPPED | TEE_SHM_DMA_BUF to
tee_shm_alloc().
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Since the tee subsystem does not keep a strong reference to its idle
shared memory buffers, it races with other threads that try to destroy a
shared memory through a close of its dma-buf fd or by unmapping the
memory.
In tee_shm_get_from_id() when a lookup in teedev->idr has been
successful, it is possible that the tee_shm is in the dma-buf teardown
path, but that path is blocked by the teedev mutex. Since we don't have
an API to tell if the tee_shm is in the dma-buf teardown path or not we
must find another way of detecting this condition.
Fix this by doing the reference counting directly on the tee_shm using a
new refcount_t refcount field. dma-buf is replaced by using
anon_inode_getfd() instead, this separates the life-cycle of the
underlying file from the tee_shm. tee_shm_put() is updated to hold the
mutex when decreasing the refcount to 0 and then remove the tee_shm from
teedev->idr before releasing the mutex. This means that the tee_shm can
never be found unless it has a refcount larger than 0.
Fixes: 967c9cca2c ("tee: generic TEE subsystem")
Cc: stable@vger.kernel.org
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Lars Persson <larper@axis.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Reported-by: Patrik Lantz <patrik.lantz@axis.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
In order to better track where in the kernel the dma-buf code is used,
put the symbols in the namespace DMA_BUF and modify all users of the
symbols to properly import the namespace to not break the build at the
same time.
Now the output of modinfo shows the use of these symbols, making it
easier to watch for users over time:
$ modinfo drivers/misc/fastrpc.ko | grep import
import_ns: DMA_BUF
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://lore.kernel.org/r/20211010124628.17691-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently TEE_SHM_DMA_BUF flag has been inappropriately used to not
register shared memory allocated for private usage by underlying TEE
driver: OP-TEE in this case. So rather add a new flag as TEE_SHM_PRIV
that can be utilized by underlying TEE drivers for private allocation
and usage of shared memory.
With this corrected, allow tee_shm_alloc_kernel_buf() to allocate a
shared memory region without the backing of dma-buf.
Cc: stable@vger.kernel.org
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Co-developed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Adds a new function tee_shm_alloc_kernel_buf() to allocate shared memory
from a kernel driver. This function can later be made more lightweight
by unnecessary dma-buf export.
Cc: stable@vger.kernel.org
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
This code was using get_user_pages*(), in a "Case 2" scenario
(DMA/RDMA), using the categorization from [1]. That means that it's
time to convert the get_user_pages*() + put_page() calls to
pin_user_pages*() + unpin_user_pages() calls.
Factor out a new, small release_registered_pages() function, in
order to consolidate the logic for discerning between
TEE_SHM_USER_MAPPED and TEE_SHM_KERNEL_MAPPED pages. This also
absorbs the kfree() call that is also required there.
There is some helpful background in [2]: basically, this is a small
part of fixing a long-standing disconnect between pinning pages, and
file systems' use of those pages.
[1] Documentation/core-api/pin_user_pages.rst
[2] "Explicit pinning of user-space pages":
https://lwn.net/Articles/807108/
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: tee-dev@lists.linaro.org
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Enable support to register kernel memory reference with TEE. This change
will allow TEE bus drivers to register memory references.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Smatch complains that "ctx" isn't checked consistently:
drivers/tee/tee_shm.c:164 tee_shm_alloc()
warn: variable dereferenced before check 'ctx' (see line 95)
I audited the callers and "ctx" can't be NULL so the check can be
removed.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
tee_shm_op_mmap() uses the TEE_SHM_USER_MAPPED flag instead of the
TEE_SHM_REGISTER flag to tell if a shared memory object is originating
from registered user space memory.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
The ctx element in struct tee_shm is always valid. So remove the now
redundant teedev element.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Private shared memory object must not be referenced from user space. To
guarantee that, don't assign an id to shared memory objects which are
driver private.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
tee_shm_priv_alloc() isn't useful in the current state and it's also not
not used so remove it.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.
tee_shm_register()->optee_shm_unregister()->check_mem_type() uses provided
user pointers for vma lookups (via __check_mem_type()), which can only by
done with untagged pointers.
Untag user pointers in this function.
Link: http://lkml.kernel.org/r/4b993f33196b3566ac81285ff8453219e2079b45.1563904656.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on 1 normalized pattern(s):
this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 285 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To facilitate additional options to get_user_pages_fast() change the
singular write parameter to be gup_flags.
This patch does not change any functionality. New functionality will
follow in subsequent patches.
Some of the get_user_pages_fast() call sites were unchanged because they
already passed FOLL_WRITE or 0 for the write parameter.
NOTE: It was suggested to change the ordering of the get_user_pages_fast()
arguments to ensure that callers were converted. This breaks the current
GUP call site convention of having the returned pages be the final
parameter. So the suggestion was rejected.
Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marshall <hubcap@omnibond.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Neither used nor correctly implemented anywhere. Just completely remove
the interface.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/226645/
Bump the file's refcount before moving the reference into the fd table,
not afterwards. The old code could drop the file's refcount to zero for a
short moment before calling get_file() via get_dma_buf().
This code can only be triggered on ARM systems that use Linaro's OP-TEE.
Fixes: 967c9cca2c ("tee: generic TEE subsystem")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
get_user_pages_fast() can return zero in certain error paths. We should
handle that or else it means we accidentally return ERR_PTR(0) which is
NULL instead of an error pointer. The callers are not expecting that
and will crash with a NULL dereference.
Fixes: 033ddf12bc ("tee: add register user memory")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
In the case that shm->pages fails to allocate, the current exit
error path will try to put_page on a null shm->pages and cause
a null pointer dereference when accessing shm->pages[n]. Fix this
by only performing the put_page and kfree on shm->pages if it
is not null.
Detected by CoverityScan, CID#1463283 ("Dereference after null check")
Fixes: 033ddf12bc ("tee: add register user memory")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
The function __tee_shm_alloc is local to the source and does
not need to be in global scope, so make it static.
Cleans up sparse warning:
symbol '__tee_shm_alloc' was not declared. Should it be static?
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Adds a start argument to the shm_register callback to allow the callback
to check memory type of the passed pages.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Now, when struct tee_shm is defined in public header,
we can inline small getter functions like this one.
Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
We need to ensure that tee_context is present until last
shared buffer will be freed.
Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Added new ioctl to allow users register own buffers as a shared memory.
Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
[jw: moved tee_shm_is_registered() declaration]
[jw: added space after __tee_shm_alloc() implementation]
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Makes creation of shm pools more flexible by adding new more primitive
functions to allocate a shm pool. This makes it easier to add driver
specific shm pool management.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Volodymyr Babchuk <vlad.babchuk@gmail.com>
dma_buf_ops are not supposed to change at runtime. All functions
working with dma_buf_ops provided by <linux/dma-buf.h> work with
const dma_buf_ops. So mark the non-const structs as const.
File size before:
text data bss dec hex filename
2026 112 0 2138 85a drivers/tee/tee_shm.o
File size After adding 'const':
text data bss dec hex filename
2138 0 0 2138 85a drivers/tee/tee_shm.o
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
This branch introduces a generic TEE framework in the kernel, to handle
trusted environemtns (security coprocessor or software implementations
such as OP-TEE/TrustZone). I'm sending it separately from the other
arm-soc driver changes to give it a little more visibility, once
the subsystem is merged, we will likely keep this in the arm₋soc
drivers branch or have the maintainers submit pull requests directly,
depending on the patch volume.
I have reviewed earlier versions in the past, and have reviewed
the latest version in person during Linaro Connect BUD17.
Here is my overall assessment of the subsystem:
* There is clearly demand for this, both for the generic
infrastructure and the specific OP-TEE implementation.
* The code has gone through a large number of reviews,
and the review comments have all been addressed, but
the reviews were not coming up with serious issues any more
and nobody volunteered to vouch for the quality.
* The user space ioctl interface is sufficient to work with the
OP-TEE driver, and it should in principle work with other
TEE implementations that follow the GlobalPlatform[1] standards,
but it might need to be extended in minor ways depending on
specific requirements of future TEE implementations
* The main downside of the API to me is how the user space
is tied to the TEE implementation in hardware or firmware,
but uses a generic way to communicate with it. This seems
to be an inherent problem with what it is trying to do,
and I could not come up with any better solution than what
is implemented here.
For a detailed history of the patch series, see
https://lkml.org/lkml/2017/3/10/1277
Conflicts: needs a fixup after the drm tree was merged, see
https://patchwork.kernel.org/patch/9691679/
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Merge tag 'armsoc-tee' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull TEE driver infrastructure and OP-TEE drivers from Arnd Bergmann:
"This introduces a generic TEE framework in the kernel, to handle
trusted environemtns (security coprocessor or software implementations
such as OP-TEE/TrustZone). I'm sending it separately from the other
arm-soc driver changes to give it a little more visibility, once the
subsystem is merged, we will likely keep this in the arm₋soc drivers
branch or have the maintainers submit pull requests directly,
depending on the patch volume.
I have reviewed earlier versions in the past, and have reviewed the
latest version in person during Linaro Connect BUD17.
Here is my overall assessment of the subsystem:
- There is clearly demand for this, both for the generic
infrastructure and the specific OP-TEE implementation.
- The code has gone through a large number of reviews, and the review
comments have all been addressed, but the reviews were not coming
up with serious issues any more and nobody volunteered to vouch for
the quality.
- The user space ioctl interface is sufficient to work with the
OP-TEE driver, and it should in principle work with other TEE
implementations that follow the GlobalPlatform[1] standards, but it
might need to be extended in minor ways depending on specific
requirements of future TEE implementations
- The main downside of the API to me is how the user space is tied to
the TEE implementation in hardware or firmware, but uses a generic
way to communicate with it. This seems to be an inherent problem
with what it is trying to do, and I could not come up with any
better solution than what is implemented here.
For a detailed history of the patch series, see
https://lkml.org/lkml/2017/3/10/1277"
* tag 'armsoc-tee' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
arm64: dt: hikey: Add optee node
Documentation: tee subsystem and op-tee driver
tee: add OP-TEE driver
tee: generic TEE subsystem
dt/bindings: add bindings for optee
Initial patch for generic TEE subsystem.
This subsystem provides:
* Registration/un-registration of TEE drivers.
* Shared memory between normal world and secure world.
* Ioctl interface for interaction with user space.
* Sysfs implementation_id of TEE driver
A TEE (Trusted Execution Environment) driver is a driver that interfaces
with a trusted OS running in some secure environment, for example,
TrustZone on ARM cpus, or a separate secure co-processor etc.
The TEE subsystem can serve a TEE driver for a Global Platform compliant
TEE, but it's not limited to only Global Platform TEEs.
This patch builds on other similar implementations trying to solve
the same problem:
* "optee_linuxdriver" by among others
Jean-michel DELORME<jean-michel.delorme@st.com> and
Emmanuel MICHEL <emmanuel.michel@st.com>
* "Generic TrustZone Driver" by Javier González <javier@javigon.com>
Acked-by: Andreas Dannenberg <dannenberg@ti.com>
Tested-by: Jerome Forissier <jerome.forissier@linaro.org> (HiKey)
Tested-by: Volodymyr Babchuk <vlad.babchuk@gmail.com> (RCAR H3)
Tested-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
