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542 commits

Author SHA1 Message Date
Lorenzo Pieralisi
af3cfdbf56 arm64: kernel: remove ARM64_CPU_SUSPEND config option
ARM64_CPU_SUSPEND config option was introduced to make code providing
context save/restore selectable only on platforms requiring power
management capabilities.

Currently ARM64_CPU_SUSPEND depends on the PM_SLEEP config option which
in turn is set by the SUSPEND config option.

The introduction of CPU_IDLE for arm64 requires that code configured
by ARM64_CPU_SUSPEND (context save/restore) should be compiled in
in order to enable the CPU idle driver to rely on CPU operations
carrying out context save/restore.

The ARM64_CPUIDLE config option (ARM64 generic idle driver) is therefore
forced to select ARM64_CPU_SUSPEND, even if there may be (ie PM_SLEEP)
failed dependencies, which is not a clean way of handling the kernel
configuration option.

For these reasons, this patch removes the ARM64_CPU_SUSPEND config option
and makes the context save/restore dependent on CPU_PM, which is selected
whenever either SUSPEND or CPU_IDLE are configured, cleaning up dependencies
in the process.

This way, code previously configured through ARM64_CPU_SUSPEND is
compiled in whenever a power management subsystem requires it to be
present in the kernel (SUSPEND || CPU_IDLE), which is the behaviour
expected on ARM64 kernels.

The cpu_suspend and cpu_init_idle CPU operations are added only if
CPU_IDLE is selected, since they are CPU_IDLE specific methods and
should be grouped and defined accordingly.

PSCI CPU operations are updated to reflect the introduced changes.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-27 11:35:33 +00:00
Mark Rutland
c623b33b4e arm64: make sys_call_table const
As with x86, mark the sys_call_table const such that it will be placed
in the .rodata section. This will cause attempts to modify the table
(accidental or deliberate) to fail when strict page permissions are in
place. In the absence of strict page permissions, there should be no
functional change.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-27 09:38:08 +00:00
Catalin Marinas
9648606946 arm64: Remove asm/syscalls.h
This patch moves the sys_rt_sigreturn_wrapper prototype to
arch/arm64/kernel/sys.c and removes the asm/syscalls.h header.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-27 09:38:08 +00:00
Catalin Marinas
0156411b18 arm64: Implement the compat_sys_call_table in C
Unlike the sys_call_table[], the compat one was implemented in sys32.S
making it impossible to notice discrepancies between the number of
compat syscalls and the __NR_compat_syscalls macro, the latter having to
be defined in asm/unistd.h as including asm/unistd32.h would cause
conflicts on __NR_* definitions. With this patch, incorrect
__NR_compat_syscalls values will result in a build-time error.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
2015-01-27 09:38:07 +00:00
Jiang Liu
0aaf0dae81 smp, ARM64: Kill SMP single function call interrupt
Commit 9a46ad6d6d "smp: make smp_call_function_many() use logic
similar to smp_call_function_single()" has unified the way to handle
single and multiple cross-CPU function calls. Now only one interrupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23 18:06:47 +00:00
Suzuki K. Poulose
2d888f48e0 arm64: Emulate SETEND for AArch32 tasks
Emulate deprecated 'setend' instruction for AArch32 bit tasks.

	setend [le/be] - Sets the endianness of EL0

On systems with CPUs which support mixed endian at EL0, the hardware
support for the instruction can be enabled by setting the SCTLR_EL1.SED
bit. Like the other emulated instructions it is controlled by an entry in
/proc/sys/abi/. For more information see :
	Documentation/arm64/legacy_instructions.txt

The instruction is emulated by setting/clearing the SPSR_EL1.E bit, which
will be reflected in the PSTATE.E in AArch32 context.

This patch also restores the native endianness for the execution of signal
handlers, since the process could have changed the endianness.

Note: All CPUs on the system must have mixed endian support at EL0. Once the
handler is registered, hotplugging a CPU which doesn't support mixed endian,
could lead to unexpected results/behavior in applications.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23 17:11:44 +00:00
Suzuki K. Poulose
736d474f0f arm64: Consolidate hotplug notifier for instruction emulation
As of now each insn_emulation has a cpu hotplug notifier that
enables/disables the CPU feature bit for the functionality. This
patch re-arranges the code, such that there is only one notifier
that runs through the list of registered emulation hooks and runs
their corresponding set_hw_mode.

We do nothing when a CPU is dying as we will set the appropriate bits
as it comes back online based on the state of the hooks.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
[catalin.marinas@arm.com: fix pr_warn compilation error]
[catalin.marinas@arm.com: remove unnecessary "insn" check]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23 17:11:30 +00:00
Suzuki K. Poulose
04597a65c5 arm64: Track system support for mixed endian EL0
This patch keeps track of the mixed endian EL0 support across
the system and provides helper functions to export it. The status
is a boolean indicating whether all the CPUs on the system supports
mixed endian at EL0.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23 17:02:19 +00:00
Robin Murphy
78d51e0b8b arm64: implement generic IOMMU configuration
Add the necessary call to of_iommu_init.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23 16:44:16 +00:00
Ard Biesheuvel
60305db988 arm64/efi: move virtmap init to early initcall
Now that the create_mapping() code in mm/mmu.c is able to support
setting up kernel page tables at initcall time, we can move the whole
virtmap creation to arm64_enable_runtime_services() instead of having
a distinct stage during early boot. This also allows us to drop the
arm64-specific EFI_VIRTMAP flag.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-22 14:59:25 +00:00
Laura Abbott
da141706ae arm64: add better page protections to arm64
Add page protections for arm64 similar to those in arm.
This is for security reasons to prevent certain classes
of exploits. The current method:

- Map all memory as either RWX or RW. We round to the nearest
  section to avoid creating page tables before everything is mapped
- Once everything is mapped, if either end of the RWX section should
  not be X, we split the PMD and remap as necessary
- When initmem is to be freed, we change the permissions back to
  RW (using stop machine if necessary to flush the TLB)
- If CONFIG_DEBUG_RODATA is set, the read only sections are set
  read only.

Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-22 14:54:29 +00:00
Laura Abbott
2f896d5866 arm64: use fixmap for text patching
When kernel text is marked as read only, it cannot be modified directly.
Use a fixmap to modify the text instead in a similar manner to
x86 and arm.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-22 11:50:56 +00:00
Mark Rutland
6083fe74b7 arm64: respect mem= for EFI
When booting with EFI, we acquire the EFI memory map after parsing the
early params. This unfortuantely renders the option useless as we call
memblock_enforce_memory_limit (which uses memblock_remove_range behind
the scenes) before we've added any memblocks. We end up removing
nothing, then adding all of memory later when efi_init calls
reserve_regions.

Instead, we can log the limit and apply this later when we do the rest
of the memblock work in memblock_init, which should work regardless of
the presence of EFI. At the same time we may as well move the early
parameter into arm64's mm/init.c, close to arm64_memblock_init.

Any memory which must be mapped (e.g. for use by EFI runtime services)
must be mapped explicitly reather than relying on the linear mapping,
which may be truncated as a result of a mem= option passed on the kernel
command line.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-16 16:21:58 +00:00
Ard Biesheuvel
7fe5d2b1da arm64/efi: handle potential failure to remap memory map
When remapping the UEFI memory map using ioremap_cache(), we
have to deal with potential failure. Note that, even if the
common case is for ioremap_cache() to return the existing linear
mapping of the memory map, we cannot rely on that to be always the
case, e.g., in the presence of a mem= kernel parameter.

At the same time, remove a stale comment and move the memmap code
together.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-16 16:18:16 +00:00
Catalin Marinas
0ce339a9e6 Merge branch 'arm64/common-esr-macros' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux
ESR_ELx definitions clean-up from Mark Rutland.

* 'arm64/common-esr-macros' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux:
  arm64: kvm: decode ESR_ELx.EC when reporting exceptions
  arm64: kvm: remove ESR_EL2_* macros
  arm64: remove ESR_EL1_* macros
  arm64: kvm: move to ESR_ELx macros
  arm64: decode ESR_ELx.EC when reporting exceptions
  arm64: move to ESR_ELx macros
  arm64: introduce common ESR_ELx_* definitions
2015-01-15 15:44:44 +00:00
Mark Rutland
60a1f02c9e arm64: decode ESR_ELx.EC when reporting exceptions
To aid the developer when something triggers an unexpected exception,
decode the ESR_ELx.EC field when logging an ESR_ELx value. This doesn't
tell the developer the specifics of the exception encoded in the
remaining IL and ISS bits, but it can be helpful to distinguish between
exception classes (e.g. SError and a data abort) without having to
manually decode the field, which can be tiresome.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
2015-01-15 12:24:22 +00:00
Mark Rutland
aed40e0144 arm64: move to ESR_ELx macros
Now that we have common ESR_ELx_* macros, move the core arm64 code over
to them.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
2015-01-15 12:24:15 +00:00
Sudeep Holla
5d425c1865 arm64: kernel: add support for cpu cache information
This patch adds support for cacheinfo on ARM64.

On ARMv8, the cache hierarchy can be identified through Cache Level ID
(CLIDR) register while the cache geometry is provided by Cache Size ID
(CCSIDR) register.

Since the architecture doesn't provide any way of detecting the cpus
sharing particular cache, device tree is used for the same purpose.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-15 11:55:07 +00:00
Ard Biesheuvel
9679be1031 arm64/efi: remove idmap manipulations from UEFI code
Now that we have moved the call to SetVirtualAddressMap() to the stub,
UEFI has no use for the ID map, so we can drop the code that installs
ID mappings for UEFI memory regions.

Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12 16:29:32 +00:00
Ard Biesheuvel
3033b84596 arm64/efi: remove free_boot_services() and friends
Now that we are calling SetVirtualAddressMap() from the stub, there is no
need to reserve boot-only memory regions, which implies that there is also
no reason to free them again later.

Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12 16:29:31 +00:00
Ard Biesheuvel
f3cdfd239d arm64/efi: move SetVirtualAddressMap() to UEFI stub
In order to support kexec, the kernel needs to be able to deal with the
state of the UEFI firmware after SetVirtualAddressMap() has been called.
To avoid having separate code paths for non-kexec and kexec, let's move
the call to SetVirtualAddressMap() to the stub: this will guarantee us
that it will only be called once (since the stub is not executed during
kexec), and ensures that the UEFI state is identical between kexec and
normal boot.

This implies that the layout of the virtual mapping needs to be created
by the stub as well. All regions are rounded up to a naturally aligned
multiple of 64 KB (for compatibility with 64k pages kernels) and recorded
in the UEFI memory map. The kernel proper reads those values and installs
the mappings in a dedicated set of page tables that are swapped in during
UEFI Runtime Services calls.

Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-01-12 16:29:12 +00:00
Linus Torvalds
ddb321a8dd Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also some kernel side fixes: uncore PMU
  driver fix, user regs sampling fix and an instruction decoder fix that
  unbreaks PEBS precise sampling"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/uncore/hsw-ep: Handle systems with only two SBOXes
  perf/x86_64: Improve user regs sampling
  perf: Move task_pt_regs sampling into arch code
  x86: Fix off-by-one in instruction decoder
  perf hists browser: Fix segfault when showing callchain
  perf callchain: Free callchains when hist entries are deleted
  perf hists: Fix children sort key behavior
  perf diff: Fix to sort by baseline field by default
  perf list: Fix --raw-dump option
  perf probe: Fix crash in dwarf_getcfi_elf
  perf probe: Fix to fall back to find probe point in symbols
  perf callchain: Append callchains only when requested
  perf ui/tui: Print backtrace symbols when segfault occurs
  perf report: Show progress bar for output resorting
2015-01-11 11:47:45 -08:00
Andy Lutomirski
88a7c26af8 perf: Move task_pt_regs sampling into arch code
On x86_64, at least, task_pt_regs may be only partially initialized
in many contexts, so x86_64 should not use it without extra care
from interrupt context, let alone NMI context.

This will allow x86_64 to override the logic and will supply some
scratch space to use to make a cleaner copy of user regs.

Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: chenggang.qcg@taobao.com
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/e431cd4c18c2e1c44c774f10758527fb2d1025c4.1420396372.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-09 11:12:28 +01:00
Ard Biesheuvel
0e63ea48b4 arm64/efi: add missing call to early_ioremap_reset()
The early ioremap support introduced by patch bf4b558eba
("arm64: add early_ioremap support") failed to add a call to
early_ioremap_reset() at an appropriate time. Without this call,
invocations of early_ioremap etc. that are done too late will go
unnoticed and may cause corruption.

This is exactly what happened when the first user of this feature
was added in patch f84d02755f ("arm64: add EFI runtime services").
The early mapping of the EFI memory map is unmapped during an early
initcall, at which time the early ioremap support is long gone.

Fix by adding the missing call to early_ioremap_reset() to
setup_arch(), and move the offending early_memunmap() to right after
the point where the early mapping of the EFI memory map is last used.

Fixes: f84d02755f ("arm64: add EFI runtime services")
Cc: <stable@vger.kernel.org>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-08 11:57:04 +00:00
Paul Walmsley
59c68329a0 arm64: fix missing asm/io.h include in kernel/smp_spin_table.c
On next-20150105, defconfig compilation breaks with:

arch/arm64/kernel/smp_spin_table.c:80:2: error: implicit declaration of function ‘ioremap_cache’ [-Werror=implicit-function-declaration]
arch/arm64/kernel/smp_spin_table.c:92:2: error: implicit declaration of function ‘writeq_relaxed’ [-Werror=implicit-function-declaration]
arch/arm64/kernel/smp_spin_table.c:101:2: error: implicit declaration of function ‘iounmap’ [-Werror=implicit-function-declaration]

Fix by including asm/io.h, which contains definitions or prototypes
for these macros or functions.

This second version incorporates a comment from Mark Rutland
<mark.rutland@arm.com> to keep the includes in alphabetical order
by filename.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-07 11:40:59 +00:00
Paul Walmsley
2c2b282d00 arm64: fix missing asm/alternative.h include in kernel/module.c
On next-20150105, defconfig compilation breaks with:

arch/arm64/kernel/module.c:408:4: error: implicit declaration of function ‘apply_alternatives’ [-Werror=implicit-function-declaration]

Fix by including asm/alternative.h, where the apply_alternatives()
prototype is declared.

This second version incorporates a comment from Mark Rutland
<mark.rutland@arm.com> to keep the includes in alphabetical order
by filename.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-07 11:40:59 +00:00
Mark Rutland
80639d4a79 arm64: sanity checks: add missing AArch32 registers
We don't currently check a number of registers exposed to AArch32 guests
(MVFR{0,1,2}_EL1 and ID_DFR0_EL1), despite the fact these describe
AArch32 feature support exposed to userspace and KVM guests similarly to
AArch64 registers which we do check. We do not expect these registers to
vary across a set of CPUs.

This patch adds said registers to the cpuinfo framework and sanity
checks. No sanity check failures have been observed on a current ARMv8
big.LITTLE platform (Juno).

Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-07 11:40:58 +00:00
Lorenzo Pieralisi
f43c27188a arm64: kernel: fix __cpu_suspend mm switch on warm-boot
On arm64 the TTBR0_EL1 register is set to either the reserved TTBR0
page tables on boot or to the active_mm mappings belonging to user space
processes, it must never be set to swapper_pg_dir page tables mappings.

When a CPU is booted its active_mm is set to init_mm even though its
TTBR0_EL1 points at the reserved TTBR0 page mappings. This implies
that when __cpu_suspend is triggered the active_mm can point at
init_mm even if the current TTBR0_EL1 register contains the reserved
TTBR0_EL1 mappings.

Therefore, the mm save and restore executed in __cpu_suspend might
turn out to be erroneous in that, if the current->active_mm corresponds
to init_mm, on resume from low power it ends up restoring in the
TTBR0_EL1 the init_mm mappings that are global and can cause speculation
of TLB entries which end up being propagated to user space.

This patch fixes the issue by checking the active_mm pointer before
restoring the TTBR0 mappings. If the current active_mm == &init_mm,
the code sets the TTBR0_EL1 to the reserved TTBR0 mapping instead of
switching back to the active_mm, which is the expected behaviour
corresponding to the TTBR0_EL1 settings when __cpu_suspend was entered.

Fixes: 95322526ef ("arm64: kernel: cpu_{suspend/resume} implementation")
Cc: <stable@vger.kernel.org> # 3.14+: 18ab7db
Cc: <stable@vger.kernel.org> # 3.14+: 714f599
Cc: <stable@vger.kernel.org> # 3.14+: c3684fb
Cc: <stable@vger.kernel.org> # 3.14+
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-23 16:38:50 +00:00
Linus Torvalds
36c0a48fe5 arm64 fixes:
Fix some fallout introduced during the merge window:
  - Build failure when PM_SLEEP is disabled but CPU_IDLE is enabled
  - Compiler warning from page table dumper w/ 48-bit VAs
  - Erroneous page table truncation in reported dump
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Given that my availability next week is likely to be poor, here are
  three arm64 fixes to resolve some issues introduced by features merged
  last week.  I was going to wait until -rc1, but it doesn't make much
  sense to sit on fixes.

  Fix some fallout introduced during the merge window:

   - Build failure when PM_SLEEP is disabled but CPU_IDLE is enabled
   - Compiler warning from page table dumper w/ 48-bit VAs
   - Erroneous page table truncation in reported dump"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: mm: dump: don't skip final region
  arm64: mm: dump: fix shift warning
  arm64: psci: Fix build breakage without PM_SLEEP
2014-12-16 14:12:33 -08:00
Linus Torvalds
eedb3d3304 Merge branch 'for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu updates from Tejun Heo:
 "Nothing interesting.  A patch to convert the remaining __get_cpu_var()
  users, another to fix non-critical off-by-one in an assertion and a
  cosmetic conversion to lockless_dereference() in percpu-ref.

  The back-merge from mainline is to receive lockless_dereference()"

* 'for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: Replace smp_read_barrier_depends() with lockless_dereference()
  percpu: Convert remaining __get_cpu_var uses in 3.18-rcX
  percpu: off by one in BUG_ON()
2014-12-11 18:36:26 -08:00
Krzysztof Kozlowski
e5e62d4752 arm64: psci: Fix build breakage without PM_SLEEP
Fix build failure of defconfig when PM_SLEEP is disabled (e.g. by
disabling SUSPEND) and CPU_IDLE enabled:

arch/arm64/kernel/psci.c:543:2: error: unknown field ‘cpu_suspend’ specified in initializer
  .cpu_suspend = cpu_psci_cpu_suspend,
  ^
arch/arm64/kernel/psci.c:543:2: warning: initialization from incompatible pointer type [enabled by default]
arch/arm64/kernel/psci.c:543:2: warning: (near initialization for ‘cpu_psci_ops.cpu_prepare’) [enabled by default]
make[1]: *** [arch/arm64/kernel/psci.o] Error 1

The cpu_operations.cpu_suspend field exists only if ARM64_CPU_SUSPEND is
defined, not CPU_IDLE.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-11 12:08:06 +00:00
Linus Torvalds
b64bb1d758 arm64 updates for 3.19
Changes include:
  - Support for alternative instruction patching from Andre
  - seccomp from Akashi
  - Some AArch32 instruction emulation, required by the Android folks
  - Optimisations for exception entry/exit code, cmpxchg, pcpu atomics
  - mmu_gather range calculations moved into core code
  - EFI updates from Ard, including long-awaited SMBIOS support
  - /proc/cpuinfo fixes to align with the format used by arch/arm/
  - A few non-critical fixes across the architecture
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "Here's the usual mixed bag of arm64 updates, also including some
  related EFI changes (Acked by Matt) and the MMU gather range cleanup
  (Acked by you).

  Changes include:
   - support for alternative instruction patching from Andre
   - seccomp from Akashi
   - some AArch32 instruction emulation, required by the Android folks
   - optimisations for exception entry/exit code, cmpxchg, pcpu atomics
   - mmu_gather range calculations moved into core code
   - EFI updates from Ard, including long-awaited SMBIOS support
   - /proc/cpuinfo fixes to align with the format used by arch/arm/
   - a few non-critical fixes across the architecture"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits)
  arm64: remove the unnecessary arm64_swiotlb_init()
  arm64: add module support for alternatives fixups
  arm64: perf: Prevent wraparound during overflow
  arm64/include/asm: Fixed a warning about 'struct pt_regs'
  arm64: Provide a namespace to NCAPS
  arm64: bpf: lift restriction on last instruction
  arm64: Implement support for read-mostly sections
  arm64: compat: align cacheflush syscall with arch/arm
  arm64: add seccomp support
  arm64: add SIGSYS siginfo for compat task
  arm64: add seccomp syscall for compat task
  asm-generic: add generic seccomp.h for secure computing mode 1
  arm64: ptrace: allow tracer to skip a system call
  arm64: ptrace: add NT_ARM_SYSTEM_CALL regset
  arm64: Move some head.text functions to executable section
  arm64: jump labels: NOP out NOP -> NOP replacement
  arm64: add support to dump the kernel page tables
  arm64: Add FIX_HOLE to permanent fixed addresses
  arm64: alternatives: fix pr_fmt string for consistency
  arm64: vmlinux.lds.S: don't discard .exit.* sections at link-time
  ...
2014-12-09 13:12:47 -08:00
Andre Przywara
932ded4b0b arm64: add module support for alternatives fixups
Currently the kernel patches all necessary instructions once at boot
time, so modules are not covered by this.
Change the apply_alternatives() function to take a beginning and an
end pointer and introduce a new variant (apply_alternatives_all()) to
cover the existing use case for the static kernel image section.
Add a module_finalize() function to arm64 to check for an
alternatives section in a module and patch only the instructions from
that specific area.
Since that module code is not touched before the module
initialization has ended, we don't need to halt the machine before
doing the patching in the module's code.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-04 10:28:24 +00:00
Daniel Thompson
cbbf2e6ed7 arm64: perf: Prevent wraparound during overflow
If the overflow threshold for a counter is set above or near the
0xffffffff boundary then the kernel may lose track of the overflow
causing only events that occur *after* the overflow to be recorded.
Specifically the problem occurs when the value of the performance counter
overtakes its original programmed value due to wrap around.

Typical solutions to this problem are either to avoid programming in
values likely to be overtaken or to treat the overflow bit as the 33rd
bit of the counter.

Its somewhat fiddly to refactor the code to correctly handle the 33rd bit
during irqsave sections (context switches for example) so instead we take
the simpler approach of avoiding values likely to be overtaken.

We set the limit to half of max_period because this matches the limit
imposed in __hw_perf_event_init(). This causes a doubling of the interrupt
rate for large threshold values, however even with a very fast counter
ticking at 4GHz the interrupt rate would only be ~1Hz.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-04 10:26:54 +00:00
Fabio Estevam
06f9eb884b arm64: Provide a namespace to NCAPS
Building arm64.allmodconfig leads to the following warning:

usb/gadget/function/f_ncm.c:203:0: warning: "NCAPS" redefined
 #define NCAPS (USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
 ^
In file included from /home/build/work/batch/arch/arm64/include/asm/io.h:32:0,
                 from /home/build/work/batch/include/linux/clocksource.h:19,
                 from /home/build/work/batch/include/clocksource/arm_arch_timer.h:19,
                 from /home/build/work/batch/arch/arm64/include/asm/arch_timer.h:27,
                 from /home/build/work/batch/arch/arm64/include/asm/timex.h:19,
                 from /home/build/work/batch/include/linux/timex.h:65,
                 from /home/build/work/batch/include/linux/sched.h:19,
                 from /home/build/work/batch/arch/arm64/include/asm/compat.h:25,
                 from /home/build/work/batch/arch/arm64/include/asm/stat.h:23,
                 from /home/build/work/batch/include/linux/stat.h:5,
                 from /home/build/work/batch/include/linux/module.h:10,
                 from /home/build/work/batch/drivers/usb/gadget/function/f_ncm.c:19:
arch/arm64/include/asm/cpufeature.h:27:0: note: this is the location of the previous definition
 #define NCAPS     2

So add a ARM64 prefix to avoid such problem.

Reported-by: Olof's autobuilder <build@lixom.net>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-04 09:57:41 +00:00
Vladimir Murzin
a2d25a5391 arm64: compat: align cacheflush syscall with arch/arm
Update handling of cacheflush syscall with changes made in arch/arm
counterpart:
 - return error to userspace when flushing syscall fails
 - split user cache-flushing into interruptible chunks
 - don't bother rounding to nearest vma

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
[will: changed internal return value from -EINTR to 0 to match arch/arm/]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-01 13:31:12 +00:00
AKASHI Takahiro
a1ae65b219 arm64: add seccomp support
secure_computing() is called first in syscall_trace_enter() so that
a system call will be aborted quickly without doing succeeding syscall
tracing if seccomp rules want to deny that system call.

On compat task, syscall numbers for system calls allowed in seccomp mode 1
are different from those on normal tasks, and so _NR_seccomp_xxx_32's need
to be redefined.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:24:59 +00:00
AKASHI Takahiro
cc5e9097c9 arm64: add SIGSYS siginfo for compat task
SIGSYS is primarily used in secure computing to notify tracer of syscall
events. This patch allows signal handler on compat task to get correct
information with SA_SIGINFO specified when this signal is delivered.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:24:59 +00:00
AKASHI Takahiro
1014c81d9a arm64: ptrace: allow tracer to skip a system call
If tracer modifies a syscall number to -1, this traced system call should
be skipped with a return value specified in x0.
This patch implements this semantics.

Please note:
* syscall entry tracing and syscall exit tracing (ftrace tracepoint and
  audit) are always executed, if enabled, even when skipping a system call
  (that is, -1).
  In this way, we can avoid a potential bug where audit_syscall_entry()
  might be called without audit_syscall_exit() at the previous system call
  being called, that would cause OOPs in audit_syscall_entry().

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
[will: fixed up conflict with blr rework]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:24:13 +00:00
AKASHI Takahiro
766a85d7bc arm64: ptrace: add NT_ARM_SYSTEM_CALL regset
This regeset is intended to be used to get and set a system call number
while tracing.
There was some discussion about possible approaches to do so:

(1) modify x8 register with ptrace(PTRACE_SETREGSET) indirectly,
    and update regs->syscallno later on in syscall_trace_enter(), or
(2) define a dedicated regset for this purpose as on s390, or
(3) support ptrace(PTRACE_SET_SYSCALL) as on arch/arm

Thinking of the fact that user_pt_regs doesn't expose 'syscallno' to
tracer as well as that secure_computing() expects a changed syscall number,
especially case of -1, to be visible before this function returns in
syscall_trace_enter(), (1) doesn't work well.
We will take (2) since it looks much cleaner.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-28 10:19:49 +00:00
Laura Abbott
034edabe6c arm64: Move some head.text functions to executable section
The head.text section is intended to be run at early bootup
before any of the regular kernel mappings have been setup.
Parts of head.text may be freed back into the buddy allocator
due to TEXT_OFFSET so for security requirements this memory
must not be executable. The suspend/resume/hotplug code path
requires some of these head.S functions to run however which
means they need to be executable. Support these conflicting
requirements by moving the few head.text functions that need
to be executable to the text section which has the appropriate
page table permissions.

Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-26 17:19:47 +00:00
Mark Rutland
6ddae41868 arm64: jump labels: NOP out NOP -> NOP replacement
In the arm64 arch_static_branch implementation we place an A64 NOP into
the instruction stream and log relevant details to a jump_entry in a
__jump_table section. Later this may be replaced with an immediate
branch without link to the code for the unlikely case.

At init time, the core calls arch_jump_label_transform_static to
initialise the NOPs. On x86 this involves inserting the optimal NOP for
a given microarchitecture, but on arm64 we only use the architectural
NOP, and hence replace each NOP with the exact same NOP. This is
somewhat pointless.

Additionally, at module load time we don't call jump_label_apply_nops to
patch the optimal NOPs in, unlike other architectures, but get away with
this because we only use the architectural NOP anyway. A later notifier
will patch NOPs with branches as required.

Similarly to x86 commit 11570da1c5 (x86/jump-label: Do not bother
updating NOPs if they are correct), we can avoid patching NOPs with
identical NOPs. Given that we only use a single NOP encoding, this means
we can NOP-out the body of arch_jump_label_transform_static entirely. As
the default __weak arch_jump_label_transform_static implementation
performs a patch, we must use an empty function to achieve this.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-26 17:19:47 +00:00
Will Deacon
c9453a3ab1 arm64: alternatives: fix pr_fmt string for consistency
Consistently use the plural form for alternatives pr_fmt strings.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 18:27:01 +00:00
Will Deacon
07c802bd7c arm64: vmlinux.lds.S: don't discard .exit.* sections at link-time
.exit.* sections may be subject to patching by the new alternatives
framework and so shouldn't be discarded at link-time. Without this patch,
such a section will result in the following linker error:

`.exit.text' referenced in section `.altinstructions' of
 drivers/built-in.o: defined in discarded section `.exit.text' of
drivers/built-in.o

Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:45 +00:00
Laura Abbott
af86e5974d arm64: Factor out fixmap initialization from ioremap
The fixmap API was originally added for arm64 for
early_ioremap purposes. It can be used for other purposes too
so move the initialization from ioremap to somewhere more
generic. This makes it obvious where the fixmap is being set
up and allows for a cleaner implementation of __set_fixmap.

Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:45 +00:00
Laura Abbott
c3684fbb44 arm64: Move cpu_resume into the text section
The function cpu_resume currently lives in the .data section.
There's no reason for it to be there since we can use relative
instructions without a problem. Move a few cpu_resume data
structures out of the assembly file so the .data annotation
can be dropped completely and cpu_resume ends up in the read
only text section.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:44 +00:00
Laura Abbott
ac2dec5f6c arm64: Switch to adrp for loading the stub vectors
The hyp stub vectors are currently loaded using adr. This
instruction has a +/- 1MB range for the loading address. If
the alignment for sections is changed the address may be more
than 1MB away, resulting in reclocation errors. Switch to using
adrp for getting the address to ensure we aren't affected by the
location of the __hyp_stub_vectors.

Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:44 +00:00
Laura Abbott
fcff588633 arm64: Treat handle_arch_irq as a function pointer
handle_arch_irq isn't actually text, it's just a function pointer.
It doesn't need to be stored in the text section and doing so
causes problesm if we ever want to make the kernel text read only.
Declare handle_arch_irq as a proper function pointer stored in
the data section.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:44 +00:00
Mark Rutland
3eebdbe5fc arm64: sanity checks: add ID_AA64DFR{0,1}_EL1
While we currently expect self-hosted debug support to be identical
across CPUs, we don't currently sanity check this.

This patch adds logging of the ID_AA64DFR{0,1}_EL1 values and associated
sanity checking code.

It's not clear to me whether we need to check PMUVer, TraceVer, and
DebugVer, as we don't currently rely on these fields at all.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:44 +00:00
Mark Rutland
efdf4211d5 arm64: sanity checks: add missing newline to print
A missing newline in the WARN_TAINT_ONCE string results in ugly and
somewhat difficult to read output in the case of a sanity check failure,
as the next print does not appear on a new line:

  Unsupported CPU feature variation.Modules linked in:

This patch adds the missing newline, fixing the output formatting.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 15:56:43 +00:00