Commit Graph

481 Commits

Author SHA1 Message Date
Andy Ross
bd72f71ece xtensa: Remove arch-specific (and empty) offsets.h
The xtensa arch code had this empty offsets.h header sitting around.
Its name collides with the autogenerated offsets.h, making it
dangerously dependent on include file path order.  Seems to be benign,
but it's freaking me out.  Remove.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Wayne Ren
bb50a88045 arch: arc: apply the new thread stack layout
The new thread stack layout is as follow:

|---------------------|
|  user stack         |
|---------------------|
| stack guard (opt.)  |
|---------------------|
|  privilege stack    |
-----------------------

For MPUv2
  * user stack is aligned to the power of 2 of user stack size
  * the stack guard is 2048 bytes
  * the default size of privileg stack is 256 bytes.
  For user thread, the following MPU regions are needded
    * one region for user stack, no need of stack guard for user stack
    * one region for stack guard when stack guard is enbaled
    * regions for memory domain.
  For kernel thread, the stack guard region will be at the top, adn
  The user stack and privilege stack will be merged.

MPUv3 is the same as V2's layout, except no need of power of 2
alignment.

* reimplement the user mode enter function. Now it's possible for
kernel thread to drop privileg to user thread.

* add a separate entry for user thread

* bug fixes in the cleanup of regs when go to user mode

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2018-02-16 12:20:16 +01:00
Wayne Ren
8d284116b0 arch: arc: modify the linker template for APPLICAITON Memory
The application memory area has a requirement of address alignment,
especially when MPU requires power of 2.

Modify the linker tmemplate to apply application memory address
alignment generation

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2018-02-16 12:20:16 +01:00
Wayne Ren
7ef2506611 arch: arc: enable US bit to check user mode
Enable us bit to check user mode more efficienly.

US is read as zero in user mode. This will allow use mode sleep
instructions, and it enables a form of denial-of-service attack
by putting the processor in sleep mode, but since interrupt
level/mask can't be set from user space that's not worse than
executing a loop without yielding.

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2018-02-16 12:20:16 +01:00
Wayne Ren
e91733c78b arch: arc: bug fixes and add user space support in secure mode
* bug fixes
* add user space support in secure mode

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2018-02-16 12:20:16 +01:00
Wayne Ren
f81dee0b2b arch: arc: add user space support for arc
* add the implementation of syscall
  * based on 'trap_s' intruction, id = 3
* add the privilege stack
  * the privilege stack is allocted with thread stack
  * for the kernel thread, the privilege stack is also a
    part of thread stack, the start of stack can be configured
    as stack guard
  * for the user thread, no stack guard, when the user stack is
    overflow, it will fall into kernel memory area which requires
    kernel privilege, privilege violation will be raised
* modify the linker template and add MPU_ADDR_ALIGN
* add user space corresponding codes in mpu
* the user sp aux reg will be part of thread context
* When user thread is interruptted for the 1st time, the context is
  saved in user stack (U bit of IRQ_CTLR is set to 1). When nest
  interrupt comes, the context is saved in thread's privilege stack
* the arc_mpu_regions.c is moved to board folder, as it's board
  specific
* the above codes have been tested through tests/kernel/mem_protect/
  userspace for MPU version 2

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2018-02-16 12:20:16 +01:00
Andy Gross
08de82c2f5 arm: mpu: nxp: Set bus master 3 to full access
This patch adjusts the default permissions on the bus master 3 (NET).
Recent changes restricted this to supervisor only, and this caused
issues with the network controllers access to memory.

Restrictions on access should really be enforced on the ARM core bus
master.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-15 12:53:16 -05:00
Andy Gross
f7ec62eb85 arm: mpu: Enable userspace support for NXP and ARM
This patch set implements the APIs and changed required to support
the user mode thread support.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-13 12:42:37 -08:00
Andy Gross
1c047c9bef arm: userspace: Add ARM userspace infrastructure
This patch adds support for userspace on ARM architectures.  Arch
specific calls for transitioning threads to user mode, system calls,
and associated handlers.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-13 12:42:37 -08:00
Andy Gross
9ccdcb9be6 arm: mpu: Add user context API placeholder
This patch adds a configure_mpu_user_context API and implements
the required function placeholders in the NXP and ARM MPU files.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-13 12:42:37 -08:00
Erwin Rol
581446d8cd linker: arm: add stm32 ccm sections
The STM32 has special Core Coupled Memory, ccm for short, that can
only be accessed through the CPU and can not be use for DMA.

The following 3 sections have been added.
- ccm_bss for zero initialized data
- ccm_data for initialized data
- ccm_noinit for uninitialized data

Signed-off-by: Erwin Rol <erwin@erwinrol.com>
2018-02-13 12:36:22 -06:00
Anas Nashif
11a9625eaf debug: remove DEBUG_INFO option
This feature is X86 only and is not used or being tested. It is legacy
feature and no one can prove it actually works. Remove it until we have
proper documentation and samples and multi architecture support.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2018-02-12 13:58:28 -08:00
Ioannis Glaropoulos
0d6fa4db0a arch: arm: define Cortex-M23, Cortex-M33 CPUs
This commit defines the Kconfig options for
ARM Cortex-M23 and Cortex-M33 CPUs. It also
udpates the generic memory map for M23 and M33
implementations.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-02-08 12:07:38 -06:00
Ioannis Glaropoulos
a0a03d7597 arch: arm: common Armv8-M support
This PR includes the required changes in order to support
conditional compilation for Armv8-M architecture. Two
variants of the Armv8-M architecture are defined:
- the Armv8-M Baseline (backwards compatible with ARMv6-M),
- the Armv8-M Mainline (backwards compatible with ARMv7-M).

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2018-02-08 12:07:38 -06:00
Chunlin Han
18560a01a4 arm: Generate privileged stacks
This patch adds the generation and incorporation of privileged stack
regions that are used by ARM user mode threads.  This patch adds the
infrastructure for privileged stacks.  Later patches will utilize the
generated stacks and helper functions.

Signed-off-by: Chunlin Han <chunlin.han@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-06 15:31:16 -08:00
Andy Gross
e8860fe8be arm: Add app data section alignment constraints
This patch adds application data section alignment constraints
to match the region definition requirements for ARM MPUs.  Most MPUs
require a minimum of 32 bytes of alignment for any regions, but some
require power of two alignment to the size of a region.

This requires that the linker align the application data section to
the size of the section.  This requires a linker pass to determine the
size.  Once this is accomplished the correct value is added to a linker
include file that is utilized in subsequent linker operations.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
2018-02-06 15:31:16 -08:00
Ding Tao
bbd307edfd arch: arm: vector_table: Support vector table soft relay
For SoCs that don't support vector table relocation in hardware, may not
support bootloader like mcuboot.

We introduce a way to relocate vector table in software by forwarding
the control of incoming IRQs to a new vector table which address is save
at fixed SRAM address.

User can change the data in that fixed SRAM address in order to relocate
vector table in software way.

Signed-off-by: Ding Tao <miyatsu@qq.com>
2018-01-26 06:57:28 +05:30
Wayne Ren
9a40bf6b7e arch: arc: Add the intial support of memory domain
Refering the ARM's implementation, the initial support of memory
domain in ARC is added:
* changes in MPU drivers
* changes in Kconfig
* codes to configure memory domain during thread swap
* changes in linker script template
* memory domain related macro definitions

the commited codes are simply tested through
samples/mpu/mem_domain_apis_test.

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2018-01-18 11:50:59 -08:00
Neil Armstrong
a9b47fc32c arm: cortex_m: linker.ld: fix relocate by moving _vector_start
The _vector_start was placed before the CONFIG_TEXT_SECTION_OFFSET, thus
adding the offset in the relocated vector table, making the table
invalid when relocated with a non null CONFIG_TEXT_SECTION_OFFSET.

This was tested using MCUboot with a 0x200 offset for the image header.

Fixes: eb48a0a73c ("arm: armv6-m: Support relocating vector table")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
2018-01-17 08:00:45 -05:00
Alberto Escolar Piedras
76f7644118 arch: native: Run Zephyr natively in a POSIX OS
A new arch (posix) which relies on pthreads to emulate the context
switching
A new soc for it (inf_clock) which emulates a CPU running at an
infinely high clock (so when the CPU is awaken it runs till completion
in 0 time)
A new board, which provides a trivial system tick timer and
irq generation.

Origin: Original

Fixes #1891

Signed-off-by: Alberto Escolar Piedras <alpi@oticon.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-27 14:16:08 -05:00
Adithya Baglody
13ac4d4264 kernel: mem_domain: Add an arch interface to configure memory domain
Add an architecure specfic code for the memory domain
configuration. This is needed to support a memory domain API
k_mem_domain_add_thread.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-12-21 11:52:27 -08:00
Wayne Ren
5f349a4d4d arch: arc: fix the comments and coding style
Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2017-12-13 12:05:33 -05:00
Wayne Ren
cdfb59a276 arch: arc: add the support of MPU version 3
MPU version 3 is included in em7d of em_starterkit 2.3.

The differences of MPU version 3 and version 2 are:

* different aux reg interface
* The address alignment requirement is 32 bytes
* supports secure mode
* supports SID (option)
* does not support memory region overlap

This commit adds the support MPU version 3 and also make some changes to
MPU version 2 to have an unified interface.

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2017-12-13 12:05:33 -05:00
Wayne Ren
528c960ae7 arch: arc: Add the support of secure mode for em
In ARC's SecureShield, a new secure mode (currently only em) is added.
The secure/normal mode is orthogonal to kernel/user mode. The
differences between secure mode and normal mode are following:

* different irq stack frame. so need to change the definition of
  _irq_stack_frame, assembly code.

* new aux regs, e.g, secure status(SEC_STAT), secure vector base
  (VECT_BASE_S)

* interrupts and exceptions, secure mode has its own vector base;
  interrupt can be configured as secure or normal through the
  interrupt priority aux reg.

* secure timers. Two secure timers (secure timer 0 and timer 1) are
  added.Here, for simplicity and backwards compatibility original
  internal timers (timer 0 and timer1) are used as sys clock of zephyr

* on reset, the processor is in secure mode and secure vector base is
  used.

Note: the mix of secure and normal mode is not supported, i.e. it's
assumed that the processor is always in secure mode.

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
2017-12-13 12:05:33 -05:00
David B. Kinder
01e59551ab doc: fix doxygen commment in x86/arch.h
API documentation missing @param command

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
2017-12-04 15:27:46 -05:00
Stephen Smalley
106b1c2050 arm: define _image_rodata_start/end
Define _image_rodata_start/end to match x86 and so that we can
refer to them in the userspace test among others.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
2017-11-28 12:29:13 -05:00
Chunlin Han
d051740ee0 arm: implement API to validate user buffer
Implement API to validate user buffer. This API will iterate
all MPU regions to check if the given buffer is user accessible
or not. For #3832.

Signed-off-by: Chunlin Han <chunlin.han@linaro.org>
2017-11-17 19:01:11 -05:00
Savinay Dharmappa
7c8a23d643 dts: arc: Add dts support for arc
Signed-off-by: Savinay Dharmappa <savinay.dharmappa@intel.com>
2017-11-15 07:21:10 -06:00
Adithya Baglody
f7b0731ce4 x86: MMU: Memory domain implementation for x86
Added support for memory domain implementation.

GH-3852

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-11-07 12:22:43 -08:00
Adithya Baglody
83bedcc912 ARM: MPU: Arch specific memory domain APIs
Added architecture specific support for memory domain destroy
and remove partition for arm and nxp. An optimized version of
remove partition was also added.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-11-07 12:22:43 -08:00
Andrew Boie
2a8684f60c x86: de-couple user mode and HW stack protection
This is intended for memory-constrained systems and will save
4K per thread, since we will no longer reserve room for or
activate a kernel stack guard page.

If CONFIG_USERSPACE is enabled, stack overflows will still be
caught in some situations:

1) User mode threads overflowing stack, since it crashes into the
kernel stack page
2) Supervisor mode threads overflowing stack, since the kernel
stack page is marked non-present for non-user threads

Stack overflows will not be caught:

1) When handling a system call
2) When the interrupt stack overflows

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-07 09:31:49 -08:00
Andrew Boie
a705eae315 gen_gdt: add debug statements and simplify logic
This is in preparation for making CONFIG_USERSPACE not
depend on CONFIG_HW_STACK_PROTECTION.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-07 09:31:49 -08:00
Gustavo Lima Chaves
97a8716a4f x86: Jailhouse port, tested for UART (# 0, polling) and LOAPIC timer
This is an introductory port for Zephyr to be run as a Jailhouse
hypervisor[1]'s "inmate cell", on x86 64-bit CPUs (running on 32-bit
mode). This was tested with their "tiny-demo" inmate demo cell
configuration, which takes one of the CPUs of the QEMU-VM root cell
config, along with some RAM and serial controller access (it will even
do nice things like reserving some L3 cache for it via Intel CAT) and
Zephyr samples:

   - hello_world
   - philosophers
   - synchronization

The final binary receives an additional boot sequence preamble that
conforms to Jailhouse's expectations (starts at 0x0 in real mode). It
will put the processor in 32-bit protected mode and then proceed to
Zephyr's __start function.

Testing it is just a matter of:
  $ mmake -C samples/<sample_dir> BOARD=x86_jailhouse JAILHOUSE_QEMU_IMG_FILE=<path_to_image.qcow2> run
  $ sudo insmod <path to jailhouse.ko>
  $ sudo jailhouse enable <path to configs/qemu-x86.cell>
  $ sudo jailhouse cell create <path to configs/tiny-demo.cell>
  $ sudo mount -t 9p -o trans/virtio host /mnt
  $ sudo jailhouse cell load tiny-demo /mnt/zephyr.bin
  $ sudo jailhouse cell start tiny-demo
  $ sudo jailhouse cell destroy tiny-demo
  $ sudo jailhouse disable
  $ sudo rmmod jailhouse

For the hello_world demo case, one should then get QEMU's serial port
output similar to:

"""
Created cell "tiny-demo"
Page pool usage after cell creation: mem 275/1480, remap 65607/131072
Cell "tiny-demo" can be loaded
CPU 3 received SIPI, vector 100
Started cell "tiny-demo"
***** BOOTING ZEPHYR OS v1.9.0 - BUILD: Sep 12 2017 20:03:22 *****
Hello World! x86
"""

Note that the Jailhouse's root cell *has to be started in xAPIC
mode* (kernel command line argument 'nox2apic') in order for this to
work. x2APIC support and its reasoning will come on a separate commit.

As a reminder, the make run target introduced for x86_jailhouse board
involves a root cell image with Jailhouse in it, to be launched and then
partitioned (with >= 2 64-bit CPUs in it).

Inmate cell configs with no JAILHOUSE_CELL_PASSIVE_COMMREG flag
set (e.g. apic-demo one) would need extra code in Zephyr to deal with
cell shutdown command responses from the hypervisor.

You may want to fine tune CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC for your
specific CPU—there is no detection from Zephyr with regard to that.

Other config differences from pristine QEMU defaults worth of mention
are:

   - there is no HPET when running as Jailhouse guest. We use the LOAPIC
     timer, instead
   - there is no PIC_DISABLE, because there is no 8259A PIC when running
     as a Jailhouse guest
   - XIP makes no sense also when running as Jailhouse guest, and both
     PHYS_RAM_ADDR/PHYS_LOAD_ADD are set to zero, what tiny-demo cell
     config is set to

This opens up new possibilities for Zephyr, so that usages beyond just
MCUs come to the table. I see special demand coming from
functional-safety related use cases on industry, automotive, etc.

[1] https://github.com/siemens/jailhouse

Reference to Jailhouse's booting preamble code:

Origin: Jailhouse
License: BSD 2-Clause
URL: https://github.com/siemens/jailhouse
commit: 607251b44397666a3cbbf859d784dccf20aba016
Purpose: Dual-licensing of inmate lib code
Maintained-by: Zephyr

Signed-off-by: Gustavo Lima Chaves <gustavo.lima.chaves@intel.com>
2017-11-07 08:58:49 -05:00
Jan Kiszka
283a0cdafb x86: MMU: Rename gen_mmu script
It's x86-only.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
2017-11-03 09:29:39 -07:00
Leandro Pereira
b007b64d30 kernel: Add option to ensure writable pages are not executable
This adds CONFIG_EXECUTE_XOR_WRITE, which is enabled by default on
systems that support controlling whether a page can contain executable
code.  This is also known as W^X[1].

Trying to add a memory domain with a page that is both executable and
writable, either for supervisor mode threads, or for user mode threads,
will result in a kernel panic.

There are few cases where a writable page should also be executable
(JIT compilers, which are most likely out of scope for Zephyr), so an
option is provided to disable the check.

Since the memory domain APIs are executed in supervisor mode, a
determined person could bypass these checks with ease.  This is seen
more as a way to avoid people shooting themselves in the foot.

[1] https://en.wikipedia.org/wiki/W%5EX

Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
2017-11-02 13:40:50 -07:00
Andrew Boie
9d24be8daf nios2: asm_inline_gcc: fix includes
This header needs toolchain.h but wasn't including it directly.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-02 13:25:01 -07:00
Andrew Boie
4b0e4f769b x86: apic: don't include headers we don't need
We were unnecessarily pulling in headers which resulted in kernel.h
being pulled in, which is undesirable since arch/cpu.h pulls in
these headers.

Added integral type headers since we do need those.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-02 13:25:01 -07:00
Andrew Boie
e4eeb09c5d x86: arch.h: remove reverse dependency
kernel.h depends on arch.h, and reverse dependencies need to be
removed. Define k_tid_t as some opaque pointer type so that arch.h
doesn't have to pull in kernel.h.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-01 13:13:25 -07:00
Andrew Boie
7d1b1212aa arm_core_mpu_dev.h: include proper headers
This header needs Zephyr's specific type definitions. It also
needs struct k_mem_partition and struct k_mem_domain, but they
are defined opaquely here instead of pulling in kernel.h (which
would create nasty dependency loops)

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-11-01 11:24:00 -07:00
Anas Nashif
780324b8ed cleanup: rename fiber/task -> thread
We still have many places talking about tasks and threads, replace those
with thread terminology.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-10-30 18:41:15 -04:00
Adithya Baglody
725de70d86 x86: MMU: Create PAE page structures and unions.
Created structures and unions needed to enable the software to
access these tables.
Also updated the helper macros to ease the usage of the MMU page
tables.

JIRA: ZEP-2511

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-10-23 10:13:07 -07:00
Bobby Noelte
2f7688bfd3 arch: arm: core: fix vector table relocate write to flash
Some SOCs (e.g. STM32F0) can map the flash to address 0 and
the flash base address at the same time. Prevent writing to
duplicate flash address which stops the SOC.

Allow Cortex M SOCs to create their own vector table relocation
function.

Provide a relocation function for STM32F0x SOCs.

Fixes #3923

Signed-off-by: Bobby Noelte <b0661n0e17e@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
2017-10-23 12:31:47 +02:00
Andrew Boie
d7631ec7e4 Revert "x86: MMU: Memory domain implementation for x86"
This reverts commit d0f6ce2d98.
2017-10-20 15:02:59 -04:00
Adithya Baglody
d0f6ce2d98 x86: MMU: Memory domain implementation for x86
Added support for memory domain implementation.

GH-3852

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-10-20 10:39:51 -07:00
Andrew Boie
d95f5374b4 x86: fix _arch_syscall_invoke6
arg6 is treated as a memory constraint. If that memory
address was expressed as an operand to 'mov' in the generated
code as an offset from the stack pointer, then the 'push'
instruction immediately before it could end up causing memory 4
bytes off from what was intended being passed in as the 6th
argument.

Add ESP register to the clobber list to fix this issue.

Fixes issues observed with k_thread_create() passing in a
NULL argument list with CONFIG_DEBUG=y.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-10-18 10:24:25 -07:00
Andrew Boie
bca15da650 userspace: treat thread stacks as kernel objects
We need to track permission on stack memory regions like we do
with other kernel objects. We want stacks to live in a memory
area that is outside the scope of memory domain permission
management. We need to be able track what stacks are in use,
and what stacks may be used by user threads trying to call
k_thread_create().

Some special handling is needed because thread stacks appear as
variously-sized arrays of struct _k_thread_stack_element which is
just a char. We need the entire array to be considered an object,
but also properly handle arrays of stacks.

Validation of stacks also requires that the bounds of the stack
are not exceeded. Various approaches were considered. Storing
the size in some header region of the stack itself would not allow
the stack to live in 'noinit'. Having a stack object be a data
structure that points to the stack buffer would confound our
current APIs for declaring stacks as arrays or struct members.
In the end, the struct _k_object was extended to store this size.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-10-16 19:02:00 -07:00
Andrew Boie
8487cd1fe7 x86: fix syscall optimization issue
These needed "memory" clobbers otherwise the compiler would do
unnecessary optimizations for parameters passed in as pointer
values.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-10-09 10:25:36 -07:00
Chunlin Han
607c9aa3cd arch: arm: add new memory partition attributes
Add execution-allowed memory partition attributes for arch arm.

Signed-off-by: Chunlin Han <chunlin.han@linaro.org>
2017-10-03 19:30:28 -04:00
Chunlin Han
e9c9702818 kernel: add memory domain APIs
Add the following application-facing memory domain APIs:

k_mem_domain_init() - to initialize a memory domain
k_mem_domain_destroy() - to destroy a memory domain
k_mem_domain_add_partition() - to add a partition into a domain
k_mem_domain_remove_partition() - to remove a partition from a domain
k_mem_domain_add_thread() - to add a thread into a domain
k_mem_domain_remove_thread() - to remove a thread from a domain

A memory domain would contain some number of memory partitions.
A memory partition is a memory region (might be RAM, peripheral
registers, flash...) with specific attributes (access permission,
e.g. privileged read/write, unprivileged read-only, execute never...).
Memory partitions would be defined by set of MPU regions or MMU tables
underneath.
A thread could only belong to a single memory domain any point in time
but a memory domain could contain multiple threads.
Threads in the same memory domain would have the same access permission
to the memory partitions belong to the memory domain.

The memory domain APIs are used by unprivileged threads to share data
to the threads in the same memory and protect sensitive data from
threads outside their domain. It is not only for improving the security
but also useful for debugging (unexpected access would cause exception).

Jira: ZEP-2281

Signed-off-by: Chunlin Han <chunlin.han@linaro.org>
2017-09-29 16:48:53 -07:00
Andrew Boie
d279979613 x86: fix _arch_syscall_invoke6()
The compiler was complaining about impossible constraints since register
constraint was provided, but there are no general purpose registers left
available.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2017-09-29 14:51:27 -07:00