Commit Graph

825571 Commits

Author SHA1 Message Date
Qian Cai
74dd022f9e arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable
When building with -Wunused-but-set-variable, the compiler shouts about
a number of pte_unmap() users, since this expands to an empty macro on
arm64:

  | mm/gup.c: In function 'gup_pte_range':
  | mm/gup.c:1727:16: warning: variable 'ptem' set but not used
  | [-Wunused-but-set-variable]
  | mm/gup.c: At top level:
  | mm/memory.c: In function 'copy_pte_range':
  | mm/memory.c:821:24: warning: variable 'orig_dst_pte' set but not used
  | [-Wunused-but-set-variable]
  | mm/memory.c:821:9: warning: variable 'orig_src_pte' set but not used
  | [-Wunused-but-set-variable]
  | mm/swap_state.c: In function 'swap_ra_info':
  | mm/swap_state.c:641:15: warning: variable 'orig_pte' set but not used
  | [-Wunused-but-set-variable]
  | mm/madvise.c: In function 'madvise_free_pte_range':
  | mm/madvise.c:318:9: warning: variable 'orig_pte' set but not used
  | [-Wunused-but-set-variable]

Rewrite pte_unmap() as a static inline function, which silences the
warnings.

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30 11:58:28 +01:00
Vincenzo Frascino
359db57c34 arm64: compat: Reduce address limit for 64K pages
With the introduction of the config option that allows to enable kuser
helpers, it is now possible to reduce TASK_SIZE_32 when these are
disabled and 64K pages are enabled. This extends the compliance with
the section 6.5.8 of the C standard (C99).

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30 11:04:50 +01:00
Will Deacon
75a19a0202 arm64: arch_timer: Ensure counter register reads occur with seqlock held
When executing clock_gettime(), either in the vDSO or via a system call,
we need to ensure that the read of the counter register occurs within
the seqlock reader critical section. This ensures that updates to the
clocksource parameters (e.g. the multiplier) are consistent with the
counter value and therefore avoids the situation where time appears to
go backwards across multiple reads.

Extend the vDSO logic so that the seqlock critical section covers the
read of the counter register as well as accesses to the data page. Since
reads of the counter system registers are not ordered by memory barrier
instructions, introduce dependency ordering from the counter read to a
subsequent memory access so that the seqlock memory barriers apply to
the counter access in both the vDSO and the system call paths.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/linux-arm-kernel/alpine.DEB.2.21.1902081950260.1662@nanos.tec.linutronix.de/
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30 11:04:23 +01:00
Xiongfeng Wang
2f1d4e24d9 firmware: arm_sdei: Prohibit probing in '_sdei_handler'
Functions called in '_sdei_handler' are needed to be marked as
'nokprobe'. Because these functions are called in NMI context and
neither the arch-code's debug infrastructure nor kprobes core supports
this.

Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-29 16:50:48 +01:00
Boyang Zhou
f08cae2f28 arm64: mmap: Ensure file offset is treated as unsigned
The file offset argument to the arm64 sys_mmap() implementation is
scaled from bytes to pages by shifting right by PAGE_SHIFT.
Unfortunately, the offset is passed in as a signed 'off_t' type and
therefore large offsets (i.e. with the top bit set) are incorrectly
sign-extended by the shift. This has been observed to cause false mmap()
failures when mapping GPU doorbells on an arm64 server part.

Change the type of the file offset argument to sys_mmap() from 'off_t'
to 'unsigned long' so that the shifting scales the value as expected.

Cc: <stable@vger.kernel.org>
Signed-off-by: Boyang Zhou <zhouby_cn@126.com>
[will: rewrote commit message]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-29 15:27:41 +01:00
Will Deacon
bc15cf701f arm64: Kconfig: Tidy up errata workaround help text
The nature of silicon errata means that the Kconfig help text for our
various software workarounds has been written by many different people.
Along the way, we've accumulated typos and inconsistencies which make
the options needlessly difficult to read.

Fix up minor issues with the help text.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-29 14:21:11 +01:00
Kees Cook
be604c616c arm64: sysreg: Make mrs_s and msr_s macros work with Clang and LTO
Clang's integrated assembler does not allow assembly macros defined
in one inline asm block using the .macro directive to be used across
separate asm blocks. LLVM developers consider this a feature and not a
bug, recommending code refactoring:

  https://bugs.llvm.org/show_bug.cgi?id=19749

As binutils doesn't allow macros to be redefined, this change uses
UNDEFINE_MRS_S and UNDEFINE_MSR_S to define corresponding macros
in-place and workaround gcc and clang limitations on redefining macros
across different assembler blocks.

Specifically, the current state after preprocessing looks like this:

asm volatile(".macro mXX_s ... .endm");
void f()
{
	asm volatile("mXX_s a, b");
}

With GCC, it gives macro redefinition error because sysreg.h is included
in multiple source files, and assembler code for all of them is later
combined for LTO (I've seen an intermediate file with hundreds of
identical definitions).

With clang, it gives macro undefined error because clang doesn't allow
sharing macros between inline asm statements.

I also seem to remember catching another sort of undefined error with
GCC due to reordering of macro definition asm statement and generated
asm code for function that uses the macro.

The solution with defining and undefining for each use, while certainly
not elegant, satisfies both GCC and clang, LTO and non-LTO.

Co-developed-by: Alex Matveev <alxmtvv@gmail.com>
Co-developed-by: Yury Norov <ynorov@caviumnetworks.com>
Co-developed-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-25 14:59:49 +01:00
Dave Martin
06a916feca arm64: Expose SVE2 features for userspace
This patch provides support for reporting the presence of SVE2 and
its optional features to userspace.

This will also enable visibility of SVE2 for guests, when KVM
support for SVE-enabled guests is available.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-23 18:02:00 +01:00
Will Deacon
dd523791c9 arm64: Kconfig: Make CONFIG_COMPAT a menuconfig entry
Make CONFIG_COMPAT a menuconfig entry so that we can place
CONFIG_KUSER_HELPERS and CONFIG_ARMV8_DEPRECATED underneath it.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-23 18:01:59 +01:00
Vincenzo Frascino
af1b3cf2c2 arm64: compat: Add KUSER_HELPERS config option
When kuser helpers are enabled the kernel maps the relative code at
a fixed address (0xffff0000). Making configurable the option to disable
them means that the kernel can remove this mapping and any access to
this memory area results in a sigfault.

Add a KUSER_HELPERS config option that can be used to disable the
mapping when it is turned off.

This option can be turned off if and only if the applications are
designed specifically for the platform and they do not make use of the
kuser helpers code.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[will: Use IS_ENABLED() instead of #ifdef]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-23 18:01:58 +01:00
Vincenzo Frascino
1255a7341b arm64: compat: Refactor aarch32_alloc_vdso_pages()
aarch32_alloc_vdso_pages() needs to be refactored to make it
easier to disable kuser helpers.

Divide the function in aarch32_alloc_kuser_vdso_page() and
aarch32_alloc_sigreturn_vdso_page().

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[will: Inlined sigpage allocation to simplify error paths]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-23 18:01:58 +01:00
Vincenzo Frascino
d1e5ca64d5 arm64: compat: Split kuser32
To make it possible to disable kuser helpers in aarch32 we need to
divide the kuser and the sigreturn functionalities.

Split the current version of kuser32 in kuser32 (for kuser helpers)
and sigreturn32 (for sigreturn helpers).

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-23 18:01:57 +01:00
Vincenzo Frascino
0d747f6585 arm64: compat: Alloc separate pages for vectors and sigpage
For AArch32 tasks, we install a special "[vectors]" page that contains
the sigreturn trampolines and kuser helpers, which is mapped at a fixed
address specified by the kuser helpers ABI.

Having the sigreturn trampolines in the same page as the kuser helpers
makes it impossible to disable the kuser helpers independently.

Follow the Arm implementation, by moving the signal trampolines out of
the "[vectors]" page and into their own "[sigpage]".

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
[will: tweaked comments and fixed sparse warning]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-23 18:01:31 +01:00
Kefeng Wang
36a2ba0775 ACPI/IORT: Reject platform device creation on NUMA node mapping failure
In a system where, through IORT firmware mappings, the SMMU device is
mapped to a NUMA node that is not online, the kernel bootstrap results
in the following crash:

  Unable to handle kernel paging request at virtual address 0000000000001388
  Mem abort info:
    ESR = 0x96000004
    Exception class = DABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
  Data abort info:
    ISV = 0, ISS = 0x00000004
    CM = 0, WnR = 0
  [0000000000001388] user address but active_mm is swapper
  Internal error: Oops: 96000004 [#1] SMP
  Modules linked in:
  CPU: 5 PID: 1 Comm: swapper/0 Not tainted 5.0.0 #15
  pstate: 80c00009 (Nzcv daif +PAN +UAO)
  pc : __alloc_pages_nodemask+0x13c/0x1068
  lr : __alloc_pages_nodemask+0xdc/0x1068
  ...
  Process swapper/0 (pid: 1, stack limit = 0x(____ptrval____))
  Call trace:
   __alloc_pages_nodemask+0x13c/0x1068
   new_slab+0xec/0x570
   ___slab_alloc+0x3e0/0x4f8
   __slab_alloc+0x60/0x80
   __kmalloc_node_track_caller+0x10c/0x478
   devm_kmalloc+0x44/0xb0
   pinctrl_bind_pins+0x4c/0x188
   really_probe+0x78/0x2b8
   driver_probe_device+0x64/0x110
   device_driver_attach+0x74/0x98
   __driver_attach+0x9c/0xe8
   bus_for_each_dev+0x84/0xd8
   driver_attach+0x30/0x40
   bus_add_driver+0x170/0x218
   driver_register+0x64/0x118
   __platform_driver_register+0x54/0x60
   arm_smmu_driver_init+0x24/0x2c
   do_one_initcall+0xbc/0x328
   kernel_init_freeable+0x304/0x3ac
   kernel_init+0x18/0x110
   ret_from_fork+0x10/0x1c
  Code: f90013b5 b9410fa1 1a9f0694 b50014c2 (b9400804)
  ---[ end trace dfeaed4c373a32da ]--

Change the dev_set_proximity() hook prototype so that it returns a
value and make it return failure if the PXM->NUMA-node mapping
corresponds to an offline node, fixing the crash.

Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Link: https://lore.kernel.org/linux-arm-kernel/20190315021940.86905-1-wangkefeng.wang@huawei.com/
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 18:16:24 +01:00
Vincenzo Frascino
81fb8736dd arm64: vdso: Fix clock_getres() for CLOCK_REALTIME
clock_getres() in the vDSO library has to preserve the same behaviour
of posix_get_hrtimer_res().

In particular, posix_get_hrtimer_res() does:

    sec = 0;
    ns = hrtimer_resolution;

where 'hrtimer_resolution' depends on whether or not high resolution
timers are enabled, which is a runtime decision.

The vDSO incorrectly returns the constant CLOCK_REALTIME_RES. Fix this
by exposing 'hrtimer_resolution' in the vDSO datapage and returning that
instead.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
[will: Use WRITE_ONCE(), move adr off COARSE path, renumber labels, use 'w' reg]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 18:15:56 +01:00
Nishad Kamdar
22e6c8087e arm64: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style
in the arm64 Hardware Architecture related files.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:28:01 +01:00
Mark Rutland
131e135f7f arm64: instrument smp_{load_acquire,store_release}
Our __smp_store_release() and __smp_load_acquire() macros use inline
assembly, which is opaque to kasan. This means that kasan can't catch
erroneous use of these.

This patch adds kasan instrumentation to both.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[will: consistently use *p as argument to sizeof]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:28:00 +01:00
Miles Chen
eea1bb2248 arm64: mm: check virtual addr in virt_to_page() if CONFIG_DEBUG_VIRTUAL=y
This change uses the original virt_to_page() (the one with __pa()) to
check the given virtual address if CONFIG_DEBUG_VIRTUAL=y.

Recently, I worked on a bug: a driver passes a symbol address to
dma_map_single() and the virt_to_page() (called by dma_map_single())
does not work for non-linear addresses after commit 9f2875912d
("arm64: mm: restrict virt_to_page() to the linear mapping").

I tried to trap the bug by enabling CONFIG_DEBUG_VIRTUAL but it
did not work - bacause the commit removes the __pa() from
virt_to_page() but CONFIG_DEBUG_VIRTUAL checks the virtual address
in __pa()/__virt_to_phys().

A simple solution is to use the original virt_to_page()
(the one with__pa()) if CONFIG_DEBUG_VIRTUAL=y.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:59 +01:00
Andrew Murray
b9585f53bc arm64: Advertise ARM64_HAS_DCPODP cpu feature
Advertise ARM64_HAS_DCPODP when both DC CVAP and DC CVADP are supported.

Even though we don't use this feature now, we provide it for consistency
with DCPOP and anticipate it being used in the future.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:59 +01:00
Andrew Murray
04a1438e56 arm64: add CVADP support to the cache maintenance helper
Allow users of dcache_by_line_op to specify cvadp as an op.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:58 +01:00
Andrew Murray
671db58181 arm64: Expose DC CVADP to userspace
ARMv8.5 builds upon the ARMv8.2 DC CVAP instruction by introducing a DC
CVADP instruction which cleans the data cache to the point of deep
persistence. Let's expose this support via the arm64 ELF hwcaps.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:56 +01:00
Andrew Murray
d16ed4105f arm64: Handle trapped DC CVADP
The ARMv8.5 DC CVADP instruction may be trapped to EL1 via
SCTLR_EL1.UCI therefore let's provide a handler for it.

Just like the CVAP instruction we use a 'sys' instruction instead of
the 'dc' alias to avoid build issues with older toolchains.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:36 +01:00
Andrew Murray
aec0bff757 arm64: HWCAP: encapsulate elf_hwcap
The introduction of AT_HWCAP2 introduced accessors which ensure that
hwcap features are set and tested appropriately.

Let's now mandate access to elf_hwcap via these accessors by making
elf_hwcap static within cpufeature.c.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:35 +01:00
Andrew Murray
aaba098fe6 arm64: HWCAP: add support for AT_HWCAP2
As we will exhaust the first 32 bits of AT_HWCAP let's start
exposing AT_HWCAP2 to userspace to give us up to 64 caps.

Whilst it's possible to use the remaining 32 bits of AT_HWCAP, we
prefer to expand into AT_HWCAP2 in order to provide a consistent
view to userspace between ILP32 and LP64. However internal to the
kernel we prefer to continue to use the full space of elf_hwcap.

To reduce complexity and allow for future expansion, we now
represent hwcaps in the kernel as ordinals and use a
KERNEL_HWCAP_ prefix. This allows us to support automatic feature
based module loading for all our hwcaps.

We introduce cpu_set_feature to set hwcaps which complements the
existing cpu_have_feature helper. These helpers allow us to clean
up existing direct uses of elf_hwcap and reduce any future effort
required to move beyond 64 caps.

For convenience we also introduce cpu_{have,set}_named_feature which
makes use of the cpu_feature macro to allow providing a hwcap name
without a {KERNEL_}HWCAP_ prefix.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
[will: use const_ilog2() and tweak documentation]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16 16:27:12 +01:00
Masami Hiramatsu
a823c35ff2 arm64: ptrace: Add function argument access API
Add regs_get_argument() which returns N th argument of the function
call. On arm64, it supports up to 8th argument.
Note that this chooses most probably assignment, in some case
it can be incorrect (e.g. passing data structure or floating
point etc.)

This enables ftrace kprobe events to access kernel function
arguments via $argN syntax.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[will: tidied up the comment a bit]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-12 17:04:27 +01:00
Masahiro Yamada
691efbedc6 arm64: vdso: use $(LD) instead of $(CC) to link VDSO
We use $(LD) to link vmlinux, modules, decompressors, etc.

VDSO is the only exceptional case where $(CC) is used as the linker
driver, but I do not know why we need to do so. VDSO uses a special
linker script, and does not link standard libraries at all.

I changed the Makefile to use $(LD) rather than $(CC). I tested this,
and VDSO worked for me.

Users will be able to use their favorite linker (e.g. lld instead of
of bfd) by passing LD= from the command line.

My plan is to rewrite all VDSO Makefiles to use $(LD), then delete
cc-ldoption.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-11 18:15:02 +01:00
Vincenzo Frascino
d263119387 arm64: compat: Reduce address limit
Currently, compat tasks running on arm64 can allocate memory up to
TASK_SIZE_32 (UL(0x100000000)).

This means that mmap() allocations, if we treat them as returning an
array, are not compliant with the sections 6.5.8 of the C standard
(C99) which states that: "If the expression P points to an element of
an array object and the expression Q points to the last element of the
same array object, the pointer expression Q+1 compares greater than P".

Redefine TASK_SIZE_32 to address the issue.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: <stable@vger.kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
[will: fixed typo in comment]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-10 17:38:12 +01:00
Jean-Philippe Brucker
827a108e35 arm64: Save and restore OSDLR_EL1 across suspend/resume
When the CPU comes out of suspend, the firmware may have modified the OS
Double Lock Register. Save it in an unused slot of cpu_suspend_ctx, and
restore it on resume.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 12:39:13 +01:00
Jean-Philippe Brucker
6fda41bf12 arm64: Clear OSDLR_EL1 on CPU boot
Some firmwares may reboot CPUs with OS Double Lock set. Make sure that
it is unlocked, in order to use debug exceptions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 12:38:31 +01:00
Will Deacon
475ba3fc19 arm64: mm: Consolidate early page table allocation
The logic for early allocation of page tables is duplicated between
pgd_kernel_pgtable_alloc() and pgd_pgtable_alloc(). Drop the duplication
by calling one from the other and renaming pgd_kernel_pgtable_alloc()
accordingly.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:50 +01:00
Yu Zhao
54c8d9119e arm64: mm: enable per pmd page table lock
Switch from per mm_struct to per pmd page table lock by enabling
ARCH_ENABLE_SPLIT_PMD_PTLOCK. This provides better granularity for
large system.

I'm not sure if there is contention on mm->page_table_lock. Given
the option comes at no cost (apart from initializing more spin
locks), why not enable it now.

We only do so when pmd is not folded, so we don't mistakenly call
pgtable_pmd_page_ctor() on pud or p4d in pgd_pgtable_alloc().

Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:50 +01:00
Anshuman Khandual
14b94d0757 KVM: ARM: Remove pgtable page standard functions from stage-2 page tables
ARM64 standard pgtable functions are going to use pgtable_page_[ctor|dtor]
or pgtable_pmd_page_[ctor|dtor] constructs. At present KVM guest stage-2
PUD|PMD|PTE level page tabe pages are allocated with __get_free_page()
via mmu_memory_cache_alloc() but released with standard pud|pmd_free() or
pte_free_kernel(). These will fail once they start calling into pgtable_
[pmd]_page_dtor() for pages which never originally went through respective
constructor functions. Hence convert all stage-2 page table page release
functions to call buddy directly while freeing pages.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:50 +01:00
Yu Zhao
369aaab845 arm64: mm: don't call page table ctors for init_mm
init_mm doesn't require page table lock to be initialized at
any level. Add a separate page table allocator for it, and the
new one skips page table ctors.

The ctors allocate memory when ALLOC_SPLIT_PTLOCKS is set. Not
calling them avoids memory leak in case we call pte_free_kernel()
on init_mm.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:50 +01:00
Yu Zhao
90292aca98 arm64: mm: use appropriate ctors for page tables
For pte page, use pgtable_page_ctor(); for pmd page, use
pgtable_pmd_page_ctor(); and for the rest (pud, p4d and pgd),
don't use any.

For now, we don't select ARCH_ENABLE_SPLIT_PMD_PTLOCK and
pgtable_pmd_page_ctor() is a nop. When we do in patch 3, we
make sure pmd is not folded so we won't mistakenly call
pgtable_pmd_page_ctor() on pud or p4d.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:50 +01:00
Will Deacon
ab6211c900 arm64: debug: Clean up brk_handler()
brk_handler() now looks pretty strange and can be refactored to drop its
funny 'handler_found' local variable altogether.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:13 +01:00
Will Deacon
453b7740eb arm64: probes: Move magic BRK values into brk-imm.h
kprobes and uprobes reserve some BRK immediates for installing their
probes. Define these along with the other reservations in brk-imm.h
and rename the ESR definitions to be consistent with the others that we
already have.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:13 +01:00
Will Deacon
fb610f2a20 arm64: debug: Remove redundant user_mode(regs) checks from debug handlers
Now that the debug hook dispatching code takes the triggering exception
level into account, there's no need for the hooks themselves to poke
around with user_mode(regs).

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:13 +01:00
Will Deacon
a22d570aee arm64: kprobes: Avoid calling kprobes debug handlers explicitly
Kprobes bypasses our debug hook registration code so that it doesn't
get tangled up with recursive debug exceptions from things like lockdep:

  http://lists.infradead.org/pipermail/linux-arm-kernel/2015-February/324385.html

However, since then, (a) the hook list has become RCU protected and (b)
the kprobes hooks were found not to filter out exceptions from userspace
correctly. On top of that, the step handler is invoked directly from
single_step_handler(), which *does* use the debug hook list, so it's
clearly not the end of the world.

For now, have kprobes use the debug hook registration API like everybody
else. We can revisit this in the future if this is found to limit
coverage significantly.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:13 +01:00
Will Deacon
26a04d84bc arm64: debug: Separate debug hooks based on target exception level
Mixing kernel and user debug hooks together is highly error-prone as it
relies on all of the hooks to figure out whether the exception came from
kernel or user, and then to act accordingly.

Make our debug hook code a little more robust by maintaining separate
hook lists for user and kernel, with separate registration functions
to force callers to be explicit about the exception levels that they
care about.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:13 +01:00
Will Deacon
cb764a69fa arm64: debug: Remove meaningless comment
The comment next to the definition of our 'break_hook' list head is
at best wrong but mainly just meaningless. Rip it out.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:12 +01:00
Will Deacon
5a9132add8 arm64: debug: Rename addr parameter for non-watchpoint exception hooks
Since the 'addr' parameter contains an UNKNOWN value for non-watchpoint
debug exceptions, rename it to 'unused' for those hooks so we don't get
tempted to use it in the future.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:12 +01:00
Will Deacon
52c6d145da arm64: debug: Remove unused return value from do_debug_exception()
do_debug_exception() goes out of its way to return a value that isn't
ever used, so just make the thing void.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 11:21:12 +01:00
Torsten Duwe
e2092740b7 kasan: Makefile: Replace -pg with CC_FLAGS_FTRACE
In preparation for arm64 supporting ftrace built on other compiler
options, let's have Makefiles remove the $(CC_FLAGS_FTRACE) flags,
whatever these may be, rather than assuming '-pg'.

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

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 10:34:59 +01:00
Torsten Duwe
e1a7eafb73 efi/arm/arm64: Makefile: Replace -pg with CC_FLAGS_FTRACE
In preparation for arm64 supporting ftrace built on other compiler
options, let's have Makefiles remove the $(CC_FLAGS_FTRACE) flags,
whatever these maybe, rather than assuming '-pg'.

While at it, fix arm32 as well. There should be no functional change as
a result of this patch.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 10:34:59 +01:00
Torsten Duwe
edf072d36d arm64: Makefile: Replace -pg with CC_FLAGS_FTRACE
In preparation for arm64 supporting ftrace built on other compiler
options, let's have the arm64 Makefiles remove the $(CC_FLAGS_FTRACE)
flags, whatever these may be, rather than assuming '-pg'.

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

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-09 10:34:59 +01:00
Alexandru Elisei
f6e564354a arm64: Use defines instead of magic numbers
Following assembly code is not trivial; make it slightly easier to read by
replacing some of the magic numbers with the defines which are already
present in sysreg.h.

Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-05 12:32:00 +01:00
Masahiro Yamada
697e96ed17 arm64: vdso: fix and clean-up Makefile
- $(call if_changed,...) must have FORCE as a prerequisite

- vdso.lds is a generated file, so it should be prefixed with
  $(obj)/ instead of $(src)/.

- cmd_vdsosym is a one-liner rule, so the assignment with '='
  is simpler.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-03 18:35:14 +01:00
Will Deacon
70b3d237bd arm64: mm: Ensure we ignore the initrd if it is placed out of range
If the initrd payload isn't completely accessible via the linear map,
then we print a warning during boot and nobble the virtual address of
the payload so that we ignore it later on.

Unfortunately, since commit c756c592e4 ("arm64: Utilize
phys_initrd_start/phys_initrd_size"), the virtual address isn't
initialised until later anyway, so we need to nobble the size of the
payload to ensure that we don't try to use it later on.

Fixes: c756c592e4 ("arm64: Utilize phys_initrd_start/phys_initrd_size")
Reported-by: Pierre Kuo <vichy.kuo@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-03 18:35:08 +01:00
Wen Yang
92606ec928 arm64: cpu_ops: fix a leaked reference by adding missing of_node_put
The call to of_get_next_child returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
  ./arch/arm64/kernel/cpu_ops.c:102:1-7: ERROR: missing of_node_put;
  acquired a node pointer with refcount incremented on line 69, but
  without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-03 13:50:35 +01:00
Will Deacon
7048a5973e arm64: mm: Make show_pte() a static function
show_pte() doesn't have any external callers, so make it static.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-03 13:36:54 +01:00