When building allmodconfig KCONFIG_ALLCONFIG=$(pwd)/arch/arm64/configs/defconfig
CONFIG_CPU_BIG_ENDIAN gets enabled. Which tends not to be what most
people want. Another concern that has come up is that ACPI isn't built
for an allmodconfig kernel today since that also depends on !CPU_BIG_ENDIAN.

Rework so that we introduce a 'choice' and default the choice to
CPU_LITTLE_ENDIAN. That means that when we build an allmodconfig kernel
it will default to CPU_LITTLE_ENDIAN that most people tends to want.
Reviewed-by: NJohn Garry <john.garry@huawei.com>
Acked-by: NWill Deacon <will@kernel.org>
Signed-off-by: NAnders Roxell <anders.roxell@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

When building allmodconfig KCONFIG_ALLCONFIG=$(pwd)/arch/arm64/configs/defconfig
CONFIG_CMDLINE_FORCE gets enabled. Which forces the user to pass the
full cmdline to CONFIG_CMDLINE="...".

Rework so that CONFIG_CMDLINE_FORCE gets set only if CONFIG_CMDLINE is
set to something except an empty string.
Suggested-by: NJohn Garry <john.garry@huawei.com>
Acked-by: NWill Deacon <will@kernel.org>
Signed-off-by: NAnders Roxell <anders.roxell@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch implements FTRACE_WITH_REGS for arm64, which allows a traced
function's arguments (and some other registers) to be captured into a
struct pt_regs, allowing these to be inspected and/or modified. This is
a building block for live-patching, where a function's arguments may be
forwarded to another function. This is also necessary to enable ftrace
and in-kernel pointer authentication at the same time, as it allows the
LR value to be captured and adjusted prior to signing.

Using GCC's -fpatchable-function-entry=N option, we can have the
compiler insert a configurable number of NOPs between the function entry
point and the usual prologue. This also ensures functions are AAPCS
compliant (e.g. disabling inter-procedural register allocation).

For example, with -fpatchable-function-entry=2, GCC 8.1.0 compiles the
following:

| unsigned long bar(void);
|
| unsigned long foo(void)
| {
|         return bar() + 1;
| }

... to:

| <foo>:
|         nop
|         nop
|         stp     x29, x30, [sp, #-16]!
|         mov     x29, sp
|         bl      0 <bar>
|         add     x0, x0, #0x1
|         ldp     x29, x30, [sp], #16
|         ret

This patch builds the kernel with -fpatchable-function-entry=2,
prefixing each function with two NOPs. To trace a function, we replace
these NOPs with a sequence that saves the LR into a GPR, then calls an
ftrace entry assembly function which saves this and other relevant
registers:

| mov	x9, x30
| bl	<ftrace-entry>

Since patchable functions are AAPCS compliant (and the kernel does not
use x18 as a platform register), x9-x18 can be safely clobbered in the
patched sequence and the ftrace entry code.

There are now two ftrace entry functions, ftrace_regs_entry (which saves
all GPRs), and ftrace_entry (which saves the bare minimum). A PLT is
allocated for each within modules.
Signed-off-by: NTorsten Duwe <duwe@suse.de>
[Mark: rework asm, comments, PLTs, initialization, commit message]
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NAmit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: NTorsten Duwe <duwe@suse.de>
Tested-by: NAmit Daniel Kachhap <amit.kachhap@arm.com>
Tested-by: NTorsten Duwe <duwe@suse.de>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Julien Thierry <jthierry@redhat.com>
Cc: Will Deacon <will@kernel.org>

Now that everything is in place, let's get the ball rolling
by allowing the corresponding config option to be selected.
Also add the required information to silicon_errata.rst.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMarc Zyngier <maz@kernel.org>

Cores affected by Neoverse-N1 #1542419 could execute a stale instruction
when a branch is updated to point to freshly generated instructions.

To workaround this issue we need user-space to issue unnecessary
icache maintenance that we can trap. Start by hiding CTR_EL0.DIC.
Reviewed-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: NJames Morse <james.morse@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

So far all arm64 devices have supported 32 bit DMA masks for their
peripherals. This is not true anymore for the Raspberry Pi 4 as most of
it's peripherals can only address the first GB of memory on a total of
up to 4 GB.

This goes against ZONE_DMA32's intent, as it's expected for ZONE_DMA32
to be addressable with a 32 bit mask. So it was decided to re-introduce
ZONE_DMA in arm64.

ZONE_DMA will contain the lower 1G of memory, which is currently the
memory area addressable by any peripheral on an arm64 device.
ZONE_DMA32 will contain the rest of the 32 bit addressable memory.
Signed-off-by: NNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Allow the user to select the workaround for TX2-219, and update
the silicon-errata.rst file to reflect this.

Cc: <stable@vger.kernel.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>

CONFIG_COMPAT_VDSO is defined by passing '-DCONFIG_COMPAT_VDSO' to the
compiler when the generic compat vDSO code is in use. It's much cleaner
and simpler to expose this as a proper Kconfig option (like x86 does),
so do that and remove the bodge.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>

The .config file and the generated include/config/auto.conf can
end up out of sync after a set of commands since
CONFIG_CROSS_COMPILE_COMPAT_VDSO is not updated correctly.

The sequence can be reproduced as follows:

$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
[...]
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- menuconfig
[set CONFIG_CROSS_COMPILE_COMPAT_VDSO="arm-linux-gnueabihf-"]
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-

Which results in:

arch/arm64/Makefile:62: CROSS_COMPILE_COMPAT not defined or empty,
the compat vDSO will not be built

even though the compat vDSO has been built:

$ file arch/arm64/kernel/vdso32/vdso.so
arch/arm64/kernel/vdso32/vdso.so: ELF 32-bit LSB pie executable, ARM,
EABI5 version 1 (SYSV), dynamically linked,
BuildID[sha1]=c67f6c786f2d2d6f86c71f708595594aa25247f6, stripped

A similar case that involves changing the configuration parameter
multiple times can be reconducted to the same family of problems.

Remove the use of CONFIG_CROSS_COMPILE_COMPAT_VDSO altogether and
instead rely on the cross-compiler prefix coming from the environment
via CROSS_COMPILE_COMPAT, much like we do for the rest of the kernel.

Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: NWill Deacon <will@kernel.org>
Signed-off-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>

This commits selects ARCH_HAS_ELF_RANDOMIZE when an arch uses the generic
topdown mmap layout functions so that this security feature is on by
default.

Note that this commit also removes the possibility for arm64 to have elf
randomization and no MMU: without MMU, the security added by randomization
is worth nothing.

Link: http://lkml.kernel.org/r/20190730055113.23635-6-alex@ghiti.frSigned-off-by: NAlexandre Ghiti <alex@ghiti.fr>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NLuis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arm64 handles top-down mmap layout in a way that can be easily reused by
other architectures, so make it available in mm.  It then introduces a new
config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other
architectures to benefit from those functions.  Note that this new config
depends on MMU being enabled, if selected without MMU support, a warning
will be thrown.

Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.frSigned-off-by: NAlexandre Ghiti <alex@ghiti.fr>
Suggested-by: NChristoph Hellwig <hch@infradead.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NLuis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The referenced file does not exist, but tagged-address-abi.rst does.
Signed-off-by: NJeremy Cline <jcline@redhat.com>
Signed-off-by: NWill Deacon <will@kernel.org>

Support for LSE atomic instructions (CONFIG_ARM64_LSE_ATOMICS) relies on
a static key to select between the legacy LL/SC implementation which is
available on all arm64 CPUs and the super-duper LSE implementation which
is available on CPUs implementing v8.1 and later.

Unfortunately, when building a kernel with CONFIG_JUMP_LABEL disabled
(e.g. because the toolchain doesn't support 'asm goto'), the static key
inside the atomics code tries to use atomics itself. This results in a
mess of circular includes and a build failure:

In file included from ./arch/arm64/include/asm/lse.h:11,
                 from ./arch/arm64/include/asm/atomic.h:16,
                 from ./include/linux/atomic.h:7,
                 from ./include/asm-generic/bitops/atomic.h:5,
                 from ./arch/arm64/include/asm/bitops.h:26,
                 from ./include/linux/bitops.h:19,
                 from ./include/linux/kernel.h:12,
                 from ./include/asm-generic/bug.h:18,
                 from ./arch/arm64/include/asm/bug.h:26,
                 from ./include/linux/bug.h:5,
                 from ./include/linux/page-flags.h:10,
                 from kernel/bounds.c:10:
./include/linux/jump_label.h: In function ‘static_key_count’:
./include/linux/jump_label.h:254:9: error: implicit declaration of function ‘atomic_read’ [-Werror=implicit-function-declaration]
  return atomic_read(&key->enabled);
         ^~~~~~~~~~~

[ ... more of the same ... ]

Since LSE atomic instructions are not critical to the operation of the
kernel, make them depend on JUMP_LABEL at compile time.
Reviewed-by: NAndrew Murray <andrew.murray@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>

arch_dma_mmap_pgprot is used for two things:

 1) to override the "normal" uncached page attributes for mapping
    memory coherent to devices that can't snoop the CPU caches
 2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older
    arm systems and some mips platforms

Replace one with the pgprot_dmacoherent macro that is already provided
by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE
handling to common code with an explicit arch opt-in.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	# m68k
Acked-by: Paul Burton <paul.burton@mips.com>		# mips

Add CONFIG_ASM_MODVERSIONS. This allows to remove one if-conditional
nesting in scripts/Makefile.build.

scripts/Makefile.build is run every time Kbuild descends into a
sub-directory. So, I want to avoid $(wildcard ...) evaluation
where possible although computing $(wildcard ...) is so cheap that
it may not make measurable performance difference.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>

This is a preparatory patch for kexec_file_load() lockdown.  A locked down
kernel needs to prevent unsigned kernel images from being loaded with
kexec_file_load().  Currently, the only way to force the signature
verification is compiling with KEXEC_VERIFY_SIG.  This prevents loading
usigned images even when the kernel is not locked down at runtime.

This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE.
Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG
turns on the signature verification but allows unsigned images to be
loaded.  KEXEC_SIG_FORCE disallows images without a valid signature.
Signed-off-by: NJiri Bohac <jbohac@suse.cz>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NMatthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: NJames Morris <jmorris@namei.org>

Most of the machinery is now in place to enable 52-bit kernel VAs that
are detectable at boot time.

This patch adds a Kconfig option for 52-bit user and kernel addresses
and plumbs in the requisite CONFIG_ macros as well as sets TCR.T1SZ,
physvirt_offset and vmemmap at early boot.

To simplify things this patch also removes the 52-bit user/48-bit kernel
kconfig option.
Signed-off-by: NSteve Capper <steve.capper@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>

KASAN_SHADOW_OFFSET is a constant that is supplied to gcc as a command
line argument and affects the codegen of the inline address sanetiser.

Essentially, for an example memory access:
    *ptr1 = val;
The compiler will insert logic similar to the below:
    shadowValue = *(ptr1 >> KASAN_SHADOW_SCALE_SHIFT + KASAN_SHADOW_OFFSET)
    if (somethingWrong(shadowValue))
        flagAnError();

This code sequence is inserted into many places, thus
KASAN_SHADOW_OFFSET is essentially baked into many places in the kernel
text.

If we want to run a single kernel binary with multiple address spaces,
then we need to do this with KASAN_SHADOW_OFFSET fixed.

Thankfully, due to the way the KASAN_SHADOW_OFFSET is used to provide
shadow addresses we know that the end of the shadow region is constant
w.r.t. VA space size:
    KASAN_SHADOW_END = ~0 >> KASAN_SHADOW_SCALE_SHIFT + KASAN_SHADOW_OFFSET

This means that if we increase the size of the VA space, the start of
the KASAN region expands into lower addresses whilst the end of the
KASAN region is fixed.

Currently the arm64 code computes KASAN_SHADOW_OFFSET at build time via
build scripts with the VA size used as a parameter. (There are build
time checks in the C code too to ensure that expected values are being
derived). It is sufficient, and indeed is a simplification, to remove
the build scripts (and build time checks) entirely and instead provide
KASAN_SHADOW_OFFSET values.

This patch removes the logic to compute the KASAN_SHADOW_OFFSET in the
arm64 Makefile, and instead we adopt the approach used by x86 to supply
offset values in kConfig. To help debug/develop future VA space changes,
the Makefile logic has been preserved in a script file in the arm64
Documentation folder.
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NSteve Capper <steve.capper@arm.com>
Signed-off-by: NWill Deacon <will@kernel.org>

Inspired by the commit 7cd01b08 ("powerpc: Add support for function
error injection"), this patch supports function error injection for
Arm64.

This patch mainly support two functions: one is regs_set_return_value()
which is used to overwrite the return value; the another function is
override_function_with_return() which is to override the probed
function returning and jump to its caller.
Reviewed-by: NMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NWill Deacon <will@kernel.org>

It is not desirable to relax the ABI to allow tagged user addresses into
the kernel indiscriminately. This patch introduces a prctl() interface
for enabling or disabling the tagged ABI with a global sysctl control
for preventing applications from enabling the relaxed ABI (meant for
testing user-space prctl() return error checking without reconfiguring
the kernel). The ABI properties are inherited by threads of the same
application and fork()'ed children but cleared on execve(). A Kconfig
option allows the overall disabling of the relaxed ABI.

The PR_SET_TAGGED_ADDR_CTRL will be expanded in the future to handle
MTE-specific settings like imprecise vs precise exceptions.
Reviewed-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NAndrey Konovalov <andreyknvl@google.com>
Signed-off-by: NWill Deacon <will@kernel.org>

RELR is a relocation packing format for relative relocations.
The format is described in a generic-abi proposal:
https://groups.google.com/d/topic/generic-abi/bX460iggiKg/discussion

The LLD linker can be instructed to pack relocations in the RELR
format by passing the flag --pack-dyn-relocs=relr.

This patch adds a new config option, CONFIG_RELR. Enabling this option
instructs the linker to pack vmlinux's relative relocations in the RELR
format, and causes the kernel to apply the relocations at startup along
with the RELA relocations. RELA relocations still need to be applied
because the linker will emit RELA relative relocations if they are
unrepresentable in the RELR format (i.e. address not a multiple of 2).

Enabling CONFIG_RELR reduces the size of a defconfig kernel image
with CONFIG_RANDOMIZE_BASE by 3.5MB/16% uncompressed, or 550KB/5%
compressed (lz4).
Signed-off-by: NPeter Collingbourne <pcc@google.com>
Tested-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NWill Deacon <will@kernel.org>

In order for things like get_user_pages() to work on ZONE_DEVICE memory,
we need a software PTE bit to identify device-backed PFNs.  Hook this up
along with the relevant helpers to join in with ARCH_HAS_PTE_DEVMAP.

[robin.murphy@arm.com: build fixes]
  Link: http://lkml.kernel.org/r/13026c4e64abc17133bbfa07d7731ec6691c0bcd.1559050949.git.robin.murphy@arm.com
Link: http://lkml.kernel.org/r/817d92886fc3b33bcbf6e105ee83a74babb3a5aa.1558547956.git.robin.murphy@arm.comSigned-off-by: NRobin Murphy <robin.murphy@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The Kdump documentation describes procedures with admins use
in order to solve issues on their systems.
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>

Converts ARM the text files to ReST, preparing them to be an
architecture book.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by Corentin Labbe <clabbe.montjoie@gmail.com> # For sun4i-ss

We only support the generic GUP now, so rename the config option to
be more clear, and always use the mm/Kconfig definition of the
symbol and select it from the arch Kconfigs.

Link: http://lkml.kernel.org/r/20190625143715.1689-11-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NKhalid Aziz <khalid.aziz@oracle.com>
Reviewed-by: NJason Gunthorpe <jgg@mellanox.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: James Hogan <jhogan@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ARCH_WANT_HUGE_PMD_SHARE config was declared in both architectures:
move this declaration in arch/Kconfig and make those architectures
select it.
Signed-off-by: NAlexandre Ghiti <alex@ghiti.fr>
Reviewed-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> # for arm64
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NPaul Walmsley <paul.walmsley@sifive.com>

Otherwise, selecting it without MODULES leads to build failures.

Fixes: 58557e48 ("arm64: Allow user selection of ARM64_MODULE_PLTS")
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Wire up the special helper functions to manipulate aliases of vmalloc
regions in the linear map.
Acked-by: NWill Deacon <will@kernel.org>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Make ARM64_MODULE_PLTS a selectable Kconfig symbol, since some people
might have very big modules spilling out of the dedicated module area
into vmalloc. Help text is copied from the ARM 32-bit counterpart and
modified to a mention of KASLR and specific ARM errata workaround(s).
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add vDSO compat support to the arm64 build system.
Signed-off-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NShijith Thotton <sthotton@marvell.com>
Tested-by: NAndre Przywara <andre.przywara@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Link: https://lkml.kernel.org/r/20190621095252.32307-16-vincenzo.frascino@arm.com

To take advantage of the commonly defined vdso interface for gettimeofday()
the architectural code requires an adaptation.

Re-implement the gettimeofday VDSO in C in order to use lib/vdso.

With the new implementation arm64 gains support for CLOCK_BOOTTIME
and CLOCK_TAI.

[ tglx: Reformatted the function line breaks ]
Signed-off-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NShijith Thotton <sthotton@marvell.com>
Tested-by: NAndre Przywara <andre.przywara@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Link: https://lkml.kernel.org/r/20190621095252.32307-5-vincenzo.frascino@arm.com

Now that Pseudo-NMI are fixed, allow the use of that option again

This reverts commit 96a13f57 ("arm64:
Kconfig: Make ARM64_PSEUDO_NMI depend on BROKEN for now").

Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NJulien Thierry <julien.thierry@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Using IRQ priority masking to enable/disable interrupts is a bit
sensitive as it requires to deal with both ICC_PMR_EL1 and PSR.I.

Introduce some validity checks to both highlight the states in which
functions dealing with IRQ enabling/disabling can (not) be called, and
bark a warning when called in an unexpected state.

Since these checks are done on hotpaths, introduce a build option to
choose whether to do the checking.

Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NJulien Thierry <julien.thierry@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Convert kdump documentation to ReST and add it to the
user faced manual, as the documents are mainly focused on
sysadmins that would be enabling kdump.

Note: the vmcoreinfo.rst has one very long title on one of its
sub-sections:

	PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_slab|PG_hwpoision|PG_head_mask|PAGE_BUDDY_MAPCOUNT_VALUE(~PG_buddy)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_offline)

I opted to break this one, into two entries with the same content,
in order to make it easier to display after being parsed in html and PDF.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: NMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.

Also since commit f467c564 ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:

    ...
    One side effect of (and the main motivation for) this change is making
    the following two definitions behave exactly the same:

        config FOO
                bool

        config FOO
                bool
                default n

    With this change, neither of these will generate a
    '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
    That might make it clearer to people that a bare 'default n' is
    redundant.
    ...
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This change makes CONFIG_ZONE_DMA32 defuly y and allows users
to overwrite it only when CONFIG_EXPERT=y.

For the SoCs that do not need CONFIG_ZONE_DMA32, this is the
first step to manage all available memory by a single
zone(normal zone) to reduce the overhead of multiple zones.

The change also fixes a build error when CONFIG_NUMA=y and
CONFIG_ZONE_DMA32=n.

arch/arm64/mm/init.c:195:17: error: use of undeclared identifier 'ZONE_DMA32'
                max_zone_pfns[ZONE_DMA32] = PFN_DOWN(max_zone_dma_phys());

Change since v1:
1. only expose CONFIG_ZONE_DMA32 when CONFIG_EXPERT=y
2. remove redundant IS_ENABLED(CONFIG_ZONE_DMA32)

Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: NMiles Chen <miles.chen@mediatek.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Although we merged support for pseudo-nmi using interrupt priority
masking in 5.1, we've since uncovered a number of non-trivial issues
with the implementation. Although there are patches pending to address
these problems, we're facing issues that prevent us from merging them at
this current time:

  https://lkml.kernel.org/r/1556553607-46531-1-git-send-email-julien.thierry@arm.com

For now, simply mark this optional feature as BROKEN in the hope that we
can fix things properly in the near future.

Cc: <stable@vger.kernel.org> # 5.1
Cc: Julien Thierry <julien.thierry@arm.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

We already mitigate erratum 1188873 affecting Cortex-A76 and
Neoverse-N1 r0p0 to r2p0. It turns out that revisions r0p0 to
r3p1 of the same cores are affected by erratum 1418040, which
has the same workaround as 1188873.

Let's expand the range of affected revisions to match 1418040,
and repaint all occurences of 1188873 to 1418040. Whilst we're
there, do a bit of reformating in silicon-errata.txt and drop
a now unnecessary dependency on ARM_ARCH_TIMER_OOL_WORKAROUND.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Revisions of the Cortex-A76 CPU prior to r4p0 are affected by an erratum
that can prevent interrupts from being taken when single-stepping.

This patch implements a software workaround to prevent userspace from
effectively being able to disable interrupts.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>