As is the case for a number of other architectures that have a 32-bit
compat mode, enable KEYS_COMPAT if both COMPAT and KEYS are enabled.
This allows AArch32 programs to use the keyctl() system call when
running on an AArch64 kernel.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

On Qualcomm Datacenter Technologies QDF2400 SoCs, the ITS hardware
implementation uses 16Bytes for Interrupt Translation Entry (ITE),
but reports an incorrect value of 8Bytes in GITS_TYPER.ITTE_size.

It might cause kernel memory corruption depending on the number
of MSI(x) that are configured and the amount of memory that has
been allocated for ITEs in its_create_device().

This patch fixes the potential memory corruption by setting the
correct ITE size to 16Bytes.

Cc: stable@vger.kernel.org
Signed-off-by: NShanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Currently, there's no good way to test for the presence of
set_memory_ro/rw/x/nx() helpers implemented by archs such as
x86, arm, arm64 and s390.

There's DEBUG_SET_MODULE_RONX and DEBUG_RODATA, however both
don't really reflect that: set_memory_*() are also available
even when DEBUG_SET_MODULE_RONX is turned off, and DEBUG_RODATA
is set by parisc, but doesn't implement above functions. Thus,
add ARCH_HAS_SET_MEMORY that is selected by mentioned archs,
where generic code can test against this.

This also allows later on to move DEBUG_SET_MODULE_RONX out of
the arch specific Kconfig to define it only once depending on
ARCH_HAS_SET_MEMORY.
Suggested-by: NLaura Abbott <labbott@redhat.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Qualcomm Datacenter Technologies Falkor v1 CPU may allocate TLB entries
using an incorrect ASID when TTBRx_EL1 is being updated. When the erratum
is triggered, page table entries using the new translation table base
address (BADDR) will be allocated into the TLB using the old ASID. All
circumstances leading to the incorrect ASID being cached in the TLB arise
when software writes TTBRx_EL1[ASID] and TTBRx_EL1[BADDR], a memory
operation is in the process of performing a translation using the specific
TTBRx_EL1 being written, and the memory operation uses a translation table
descriptor designated as non-global. EL2 and EL3 code changing the EL1&0
ASID is not subject to this erratum because hardware is prohibited from
performing translations from an out-of-context translation regime.

Consider the following pseudo code.

  write new BADDR and ASID values to TTBRx_EL1

Replacing the above sequence with the one below will ensure that no TLB
entries with an incorrect ASID are used by software.

  write reserved value to TTBRx_EL1[ASID]
  ISB
  write new value to TTBRx_EL1[BADDR]
  ISB
  write new value to TTBRx_EL1[ASID]
  ISB

When the above sequence is used, page table entries using the new BADDR
value may still be incorrectly allocated into the TLB using the reserved
ASID. Yet this will not reduce functionality, since TLB entries incorrectly
tagged with the reserved ASID will never be hit by a later instruction.

Based on work by Shanker Donthineni <shankerd@codeaurora.org>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NChristopher Covington <cov@codeaurora.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

There are multiple architectures that support CONFIG_DEBUG_RODATA and
CONFIG_SET_MODULE_RONX. These options also now have the ability to be
turned off at runtime. Move these to an architecture independent
location and make these options def_bool y for almost all of those
arches.
Signed-off-by: NLaura Abbott <labbott@redhat.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NKees Cook <keescook@chromium.org>

The NUMA code may get confused by the presence of NOMAP regions within
zones, resulting in spurious BUG() checks where the node id deviates
from the containing zone's node id.

Since the kernel has no business reasoning about node ids of pages it
does not own in the first place, enable CONFIG_HOLES_IN_ZONE to ensure
that such pages are disregarded.
Acked-by: NRobert Richter <rrichter@cavium.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Remove the 'HAVE_KPROBES' dependency from the HAVE_KRETPROBES line,
since HAVE_KPROBES is already selected unconditionally in the Kconfig
line above this one.
Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David A. Long <dave.long@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/148637486369.19245.316601692744886725.stgit@devboxSigned-off-by: NIngo Molnar <mingo@kernel.org>

During a TLB invalidate sequence targeting the inner shareable domain,
Falkor may prematurely complete the DSB before all loads and stores using
the old translation are observed. Instruction fetches are not subject to
the conditions of this erratum. If the original code sequence includes
multiple TLB invalidate instructions followed by a single DSB, onle one of
the TLB instructions needs to be repeated to work around this erratum.
While the erratum only applies to cases in which the TLBI specifies the
inner-shareable domain (*IS form of TLBI) and the DSB is ISH form or
stronger (OSH, SYS), this changes applies the workaround overabundantly--
to local TLBI, DSB NSH sequences as well--for simplicity.

Based on work by Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: NChristopher Covington <cov@codeaurora.org>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Fix warning:
"(COMPAT) selects COMPAT_BINFMT_ELF which has unmet direct dependencies
(COMPAT && BINFMT_ELF)"
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

x86 has an option CONFIG_DEBUG_VIRTUAL to do additional checks
on virt_to_phys calls. The goal is to catch users who are calling
virt_to_phys on non-linear addresses immediately. This inclues callers
using virt_to_phys on image addresses instead of __pa_symbol. As features
such as CONFIG_VMAP_STACK get enabled for arm64, this becomes increasingly
important. Add checks to catch bad virt_to_phys usage.
Reviewed-by: NMark Rutland <mark.rutland@arm.com>
Tested-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NLaura Abbott <labbott@redhat.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

This patch provides APEI arch-specific bits for ARM64

Meanwhile,
 (1) Move HEST type (ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) checking to
     a generic place.
 (2) Select HAVE_ACPI_APEI when EFI and ACPI is set on ARM64, because
     arch_apei_get_mem_attribute is using efi_mem_attributes() on
     ARM64.
Signed-off-by: NTomasz Nowicki <tomasz.nowicki@linaro.org>
Tested-by: NJonathan (Zhixiong) Zhang <zjzhang@codeaurora.org>
Signed-off-by: NFu Wei <fu.wei@linaro.org>
[ Fu Wei: improve && upstream ]
Acked-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NTyler Baicar <tbaicar@codeaurora.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This patch adds the Kconfig option to enable support for TTBR0 PAN
emulation. The option is default off because of a slight performance hit
when enabled, caused by the additional TTBR0_EL1 switching during user
access operations or exception entry/exit code.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch moves arm64's struct thread_info from the task stack into
task_struct. This protects thread_info from corruption in the case of
stack overflows, and makes its address harder to determine if stack
addresses are leaked, making a number of attacks more difficult. Precise
detection and handling of overflow is left for subsequent patches.

Largely, this involves changing code to store the task_struct in sp_el0,
and acquire the thread_info from the task struct. Core code now
implements current_thread_info(), and as noted in <linux/sched.h> this
relies on offsetof(task_struct, thread_info) == 0, enforced by core
code.

This change means that the 'tsk' register used in entry.S now points to
a task_struct, rather than a thread_info as it used to. To make this
clear, the TI_* field offsets are renamed to TSK_TI_*, with asm-offsets
appropriately updated to account for the structural change.

Userspace clobbers sp_el0, and we can no longer restore this from the
stack. Instead, the current task is cached in a per-cpu variable that we
can safely access from early assembly as interrupts are disabled (and we
are thus not preemptible).

Both secondary entry and idle are updated to stash the sp and task
pointer separately.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Tested-by: NLaura Abbott <labbott@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch adds support for uprobe on ARM64 architecture.

Unit tests for following have been done so far and they have been found
working
    1. Step-able instructions, like sub, ldr, add etc.
    2. Simulation-able like ret, cbnz, cbz etc.
    3. uretprobe
    4. Reject-able instructions like sev, wfe etc.
    5. trapped and abort xol path
    6. probe at unaligned user address.
    7. longjump test cases

Currently it does not support aarch32 instruction probing.
Signed-off-by: NPratyush Anand <panand@redhat.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The RANDOMIZE_MODULE_REGION_FULL Kconfig option allows KASLR to be
configured in such a way that kernel modules and the core kernel are
allocated completely independently, which implies that modules are likely
to require branches via PLT entries to reach the core kernel. The dynamic
ftrace code does not expect that, and assumes that it can patch module
code to perform a relative branch to anywhere in the core kernel. This
may result in errors such as

  branch_imm_common: offset out of range
  ------------[ cut here ]------------
  WARNING: CPU: 3 PID: 196 at kernel/trace/ftrace.c:1995 ftrace_bug+0x220/0x2e8
  Modules linked in:

  CPU: 3 PID: 196 Comm: systemd-udevd Not tainted 4.8.0-22-generic #24
  Hardware name: AMD Seattle/Seattle, BIOS 10:34:40 Oct  6 2016
  task: ffff8d1bef7dde80 task.stack: ffff8d1bef6b0000
  PC is at ftrace_bug+0x220/0x2e8
  LR is at ftrace_process_locs+0x330/0x430

So make RANDOMIZE_MODULE_REGION_FULL mutually exclusive with DYNAMIC_FTRACE
at the Kconfig level.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

This came to light when implementing native 64-bit atomics for ARCv2.

The atomic64 self-test code uses CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
to check whether atomic64_dec_if_positive() is available.  It seems it
was needed when not every arch defined it.  However as of current code
the Kconfig option seems needless

 - for CONFIG_GENERIC_ATOMIC64 it is auto-enabled in lib/Kconfig and a
   generic definition of API is present lib/atomic64.c
 - arches with native 64-bit atomics select it in arch/*/Kconfig and
   define the API in their headers

So I see no point in keeping the Kconfig option

Compile tested for:
 - blackfin (CONFIG_GENERIC_ATOMIC64)
 - x86 (!CONFIG_GENERIC_ATOMIC64)
 - ia64

Link: http://lkml.kernel.org/r/1473703083-8625-3-git-send-email-vgupta@synopsys.comSigned-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ming Lin <ming.l@ssi.samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Arm64 supports gigantic pages after commit 084bd298 ("ARM64: mm:
HugeTLB support.") however, it can only be allocated at boottime and
can't be freed.

This patch selects ARCH_HAS_GIGANTIC_PAGE to make gigantic pages can be
allocated and freed at runtime for arch arm64.

Link: http://lkml.kernel.org/r/1475227569-63446-3-git-send-email-xieyisheng1@huawei.comSigned-off-by: NYisheng Xie <xieyisheng1@huawei.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NHillf Danton <hillf.zj@alibaba-inc.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

SBBR mentions SPCR as a mandatory ACPI table.  So enable it for ARM64

Earlycon should be set up as early as possible.  ACPI boot tables are
mapped in arch/arm64/kernel/acpi.c:acpi_boot_table_init() that
is called from setup_arch() and that's where we parse SPCR.
So it has to be opted-in per-arch.

When ACPI_SPCR_TABLE is defined initialization of DT earlycon is
deferred until the DT/ACPI decision is done.  Initialize DT earlycon
if ACPI is disabled.
Acked-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NAleksey Makarov <aleksey.makarov@linaro.org>
Tested-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: NChristopher Covington <cov@codeaurora.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The arm64 forces CONFIG_SMP=y with commit 4b3dc967, no need to
add SMP dependence for NUMA.
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Move OF_NUMA select under NUMA config, and select ACPI_NUMA
when ACPI enabled.
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Instead of comparing the name to a magic string, use archdata to
explicitly communicate whether the arch timer is suitable for
direct vdso access.
Acked-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NRussell King <rmk+kernel@armlinux.org.uk>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NScott Wood <oss@buserror.net>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

To make each percpu area allocated from its local numa node. Without this
patch, all percpu areas will be allocated from the node which cpu0 belongs
to.
Signed-off-by: NZhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Any arm64 based parts that have cache aliasing issues can set it
manually.  Apparently dragged in from ARM(32) defaults in commit
8c2c3df3 "arm64: Build infrastructure".
Signed-off-by: NKim Phillips <kim.phillips@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Cortex-A53 erratum 843419 is worked around by the linker, although it is
a configure-time option to GCC as to whether ld is actually asked to
apply the workaround or not.

This patch ensures that we pass --fix-cortex-a53-843419 to the linker
when both CONFIG_ARM64_ERRATUM_843419=y and the linker supports the
option.
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Follow the example set by x86 in commit 9ccaf77c ("x86/mm:
Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option"), and
make these protections a fundamental security feature rather than an
opt-in. This also results in a minor code simplification.

For those rare cases when users wish to disable this protection (e.g.
for debugging), this can be done by passing 'rodata=off' on the command
line.

As DEBUG_RODATA_ALIGN is only intended to address a performance/memory
tradeoff, and does not affect correctness, this is left user-selectable.
DEBUG_MODULE_RONX is also left user-selectable until the core code
provides a boot-time option to disable the protection for debugging
use-cases.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NKees Cook <keescook@chromium.org>
Acked-by: NLaura Abbott <labbott@redhat.com>
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

DEBUG_PAGEALLOC removes the valid bit of page table entries to prevent
any access to unallocated memory. Hibernate uses this as a hint that those
pages don't need to be saved/restored. This patch adds the
kernel_page_present() function it uses.

hibernate.c copies the resume kernel's linear map for use during restore.
Add _copy_pte() to fill-in the holes made by DEBUG_PAGEALLOC in the resume
kernel, so we can restore data the original kernel had at these addresses.

Finally, DEBUG_PAGEALLOC means the linear-map alias of KERNEL_START to
KERNEL_END may have holes in it, so we can't lazily clean this whole
area to the PoC. Only clean the new mmuoff region, and the kernel/kvm
idmaps.

This reverts commit da24eb1f.
Reported-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJames Morse <james.morse@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

This replaces:

- "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB" as this can
  now be selected directly.

- "select ARCH_WANT_OPTIONAL_GPIOLIB" with no dependency: GPIOLIB
  is now selectable by everyone, so we need not declare our
  intent to select it.

Cc: Michael Büsch <m@bues.ch>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Selecting CONFIG_RANDOMIZE_BASE=y and CONFIG_MODULES=n fails to build
the module PLTs support:

  CC      arch/arm64/kernel/module-plts.o
/work/Linux/linux-2.6-aarch64/arch/arm64/kernel/module-plts.c: In function ‘module_emit_plt_entry’:
/work/Linux/linux-2.6-aarch64/arch/arm64/kernel/module-plts.c:32:49: error: dereferencing pointer to incomplete type ‘struct module’

This patch selects ARM64_MODULE_PLTS conditionally only if MODULES is
enabled.

Fixes: f80fb3a3 ("arm64: add support for kernel ASLR")
Cc: <stable@vger.kernel.org> # 4.6+
Reported-by: NJeff Vander Stoep <jeffv@google.com>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Enables CONFIG_HARDENED_USERCOPY checks on arm64. As done by KASAN in -next,
renames the low-level functions to __arch_copy_*_user() so a static inline
can do additional work before the copy.
Signed-off-by: NKees Cook <keescook@chromium.org>

The pre-handler of this special 'trampoline' kprobe executes the return
probe handler functions and restores original return address in ELR_EL1.
This way the saved pt_regs still hold the original register context to be
carried back to the probed kernel function.
Signed-off-by: NSandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: NDavid A. Long <dave.long@linaro.org>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add support for basic kernel probes(kprobes) and jump probes
(jprobes) for ARM64.

Kprobes utilizes software breakpoint and single step debug
exceptions supported on ARM v8.

A software breakpoint is placed at the probe address to trap the
kernel execution into the kprobe handler.

ARM v8 supports enabling single stepping before the break exception
return (ERET), with next PC in exception return address (ELR_EL1). The
kprobe handler prepares an executable memory slot for out-of-line
execution with a copy of the original instruction being probed, and
enables single stepping. The PC is set to the out-of-line slot address
before the ERET. With this scheme, the instruction is executed with the
exact same register context except for the PC (and DAIF) registers.

Debug mask (PSTATE.D) is enabled only when single stepping a recursive
kprobe, e.g.: during kprobes reenter so that probed instruction can be
single stepped within the kprobe handler -exception- context.
The recursion depth of kprobe is always 2, i.e. upon probe re-entry,
any further re-entry is prevented by not calling handlers and the case
counted as a missed kprobe).

Single stepping from the x-o-l slot has a drawback for PC-relative accesses
like branching and symbolic literals access as the offset from the new PC
(slot address) may not be ensured to fit in the immediate value of
the opcode. Such instructions need simulation, so reject
probing them.

Instructions generating exceptions or cpu mode change are rejected
for probing.

Exclusive load/store instructions are rejected too.  Additionally, the
code is checked to see if it is inside an exclusive load/store sequence
(code from Pratyush).

System instructions are mostly enabled for stepping, except MSR/MRS
accesses to "DAIF" flags in PSTATE, which are not safe for
probing.

This also changes arch/arm64/include/asm/ptrace.h to use
include/asm-generic/ptrace.h.

Thanks to Steve Capper and Pratyush Anand for several suggested
Changes.
Signed-off-by: NSandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: NDavid A. Long <dave.long@linaro.org>
Signed-off-by: NPratyush Anand <panand@redhat.com>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64, including supporting
functions and defines.
Signed-off-by: NDavid A. Long <dave.long@linaro.org>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: Remove unused functions]
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add three new files, kexec.h, machine_kexec.c and relocate_kernel.S to the
arm64 architecture that add support for the kexec re-boot mechanism
(CONFIG_KEXEC) on arm64 platforms.
Signed-off-by: NGeoff Levand <geoff@infradead.org>
Reviewed-by: NJames Morse <james.morse@arm.com>
[catalin.marinas@arm.com: removed dead code following James Morse's comments]
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This reverts commit 6b14c517.

The original patch and UBSAN+KASAN enabled causes Linux to fail to link
with:

lib/built-in.o: In function `get_signed_val':
lib/ubsan.c:93: undefined reference to `__ashlti3'
lib/ubsan.c:93: undefined reference to `__ashrti3'
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch adds support for ACPI_TABLE_UPGRADE for ARM64

To access initrd image we need to move initialization
of linear mapping a bit earlier.

The implementation of the feature acpi_table_upgrade()
(drivers/acpi/tables.c) works with initrd data represented as an array
in virtual memory.  It uses some library utility to find the redefined
tables in that array and iterates over it to copy the data to new
allocated memory.  So to access the initrd data via fixmap
we need to rewrite it considerably.

In x86 arch, kernel memory is already mapped by the time when
acpi_table_upgrade() and acpi_boot_table_init() are called so I
think that we can just move this mapping one function earlier too.
Signed-off-by: NJon Masters <jcm@redhat.com>
Signed-off-by: NAleksey Makarov <aleksey.makarov@linaro.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add ARCH_HAS_KCOV to ARM64 config. To avoid potential crashes, disable
instrumentation of the files in arch/arm64/kvm/hyp/*.
Signed-off-by: NAlexander Potapenko <glider@google.com>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Tested-by: NJames Morse <james.morse@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The gcc support __SIZEOF_INT128__ and __int128 in arm64, thus,
enable ARCH_SUPPORTS_INT128 to make mul_u64_u32_shr() a bit
more efficient in scheduler.
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The PCI_MSI symbol is used inconsistently throughout the tree, with some
drivers using 'select' and others using 'depends on', or using conditional
selects.  This keeps causing problems; the latest one is a result of
ARCH_ALPINE using a 'select' statement to enable its platform-specific MSI
driver without enabling MSI:

  warning: (ARCH_ALPINE) selects ALPINE_MSI which has unmet direct dependencies (PCI && PCI_MSI)
  drivers/irqchip/irq-alpine-msi.c:104:15: error: variable 'alpine_msix_domain_info' has initializer but incomplete type
   static struct msi_domain_info alpine_msix_domain_info = {
		 ^~~~~~~~~~~~~~~
  drivers/irqchip/irq-alpine-msi.c:105:2: error: unknown field 'flags' specified in initializer
    .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
    ^
  drivers/irqchip/irq-alpine-msi.c:105:11: error: 'MSI_FLAG_USE_DEF_DOM_OPS' undeclared here (not in a function)
    .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
	     ^~~~~~~~~~~~~~~~~~~~~~~~

There is little reason to enable PCI support for a platform that uses MSI
but then leave MSI disabled at compile time.

Select PCI_MSI from irqchips that implement MSI, and make PCI host bridges
that use MSI on ARM depend on PCI_MSI_IRQ_DOMAIN.

For all three architectures that support PCI_MSI_IRQ_DOMAIN (ARM, ARM64,
X86), enable it by default whenever MSI is enabled.

[bhelgaas: changelog, omit crypto config change]
Suggested-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>

Implement pci_acpi_scan_root() and other arch-specific calls so ARM64 can
use ACPI to setup and enumerate PCI buses.

Use memory-mapped configuration space information from either the ACPI
_CBA method or the MCFG table and the ECAM library and generic ECAM config
accessor ops.

Implement acpi_pci_bus_find_domain_nr() to retrieve the domain number from
the acpi_pci_root structure.

Implement pcibios_add_bus() and pcibios_remove_bus() to call
acpi_pci_add_bus() and acpi_pci_remove_bus() for ACPI slot management and
other configuration.
Signed-off-by: NTomasz Nowicki <tn@semihalf.com>
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

This patch allows to build the whole kernel with GCC plugins. It was ported from
grsecurity/PaX. The infrastructure supports building out-of-tree modules and
building in a separate directory. Cross-compilation is supported too.
Currently the x86, arm, arm64 and uml architectures enable plugins.

The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory
there. The plugins compile with these options:
 * -fno-rtti: gcc is compiled with this option so the plugins must use it too
 * -fno-exceptions: this is inherited from gcc too
 * -fasynchronous-unwind-tables: this is inherited from gcc too
 * -ggdb: it is useful for debugging a plugin (better backtrace on internal
    errors)
 * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h)
 * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version
    variable, plugin-version.h)

The infrastructure introduces a new Makefile target called gcc-plugins. It
supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script
chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++).
This script also checks the availability of the included headers in
scripts/gcc-plugins/gcc-common.h.

The gcc-common.h header contains frequently included headers for GCC plugins
and it has a compatibility layer for the supported gcc versions.

The gcc-generate-*-pass.h headers automatically generate the registration
structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes.

Note that 'make clean' keeps the *.so files (only the distclean or mrproper
targets clean all) because they are needed for out-of-tree modules.

Based on work created by the PaX Team.
Signed-off-by: NEmese Revfy <re.emese@gmail.com>
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NMichal Marek <mmarek@suse.com>