Commit Graph

247 Commits

Author SHA1 Message Date
Alexandru Elisei
8d56e5c5a9 arm64: Treat ESR_ELx as a 64-bit register
In the initial release of the ARM Architecture Reference Manual for
ARMv8-A, the ESR_ELx registers were defined as 32-bit registers. This
changed in 2018 with version D.a (ARM DDI 0487D.a) of the architecture,
when they became 64-bit registers, with bits [63:32] defined as RES0. In
version G.a, a new field was added to ESR_ELx, ISS2, which covers bits
[36:32].  This field is used when the Armv8.7 extension FEAT_LS64 is
implemented.

As a result of the evolution of the register width, Linux stores it as
both a 64-bit value and a 32-bit value, which hasn't affected correctness
so far as Linux only uses the lower 32 bits of the register.

Make the register type consistent and always treat it as 64-bit wide. The
register is redefined as an "unsigned long", which is an unsigned
double-word (64-bit quantity) for the LP64 machine (aapcs64 [1], Table 1,
page 14). The type was chosen because "unsigned int" is the most frequent
type for ESR_ELx and because FAR_ELx, which is used together with ESR_ELx
in exception handling, is also declared as "unsigned long". The 64-bit type
also makes adding support for architectural features that use fields above
bit 31 easier in the future.

The KVM hypervisor will receive a similar update in a subsequent patch.

[1] https://github.com/ARM-software/abi-aa/releases/download/2021Q3/aapcs64.pdf

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220425114444.368693-4-alexandru.elisei@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-29 19:26:27 +01:00
Mark Brown
b4adc83b07 arm64/sme: System register and exception syndrome definitions
The arm64 Scalable Matrix Extension (SME) adds some new system registers,
fields in existing system registers and exception syndromes. This patch
adds definitions for these for use in future patches implementing support
for this extension.

Since SME will be the first user of FEAT_HCX in the kernel also include
the definitions for enumerating it and the HCRX system register it adds.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-6-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-22 18:50:43 +01:00
Linus Torvalds
194dfe88d6 asm-generic updates for 5.18
There are three sets of updates for 5.18 in the asm-generic tree:
 
  - The set_fs()/get_fs() infrastructure gets removed for good. This
    was already gone from all major architectures, but now we can
    finally remove it everywhere, which loses some particularly
    tricky and error-prone code.
    There is a small merge conflict against a parisc cleanup, the
    solution is to use their new version.
 
  - The nds32 architecture ends its tenure in the Linux kernel. The
    hardware is still used and the code is in reasonable shape, but
    the mainline port is not actively maintained any more, as all
    remaining users are thought to run vendor kernels that would never
    be updated to a future release.
    There are some obvious conflicts against changes to the removed
    files.
 
  - A series from Masahiro Yamada cleans up some of the uapi header
    files to pass the compile-time checks.
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Merge tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "There are three sets of updates for 5.18 in the asm-generic tree:

   - The set_fs()/get_fs() infrastructure gets removed for good.

     This was already gone from all major architectures, but now we can
     finally remove it everywhere, which loses some particularly tricky
     and error-prone code. There is a small merge conflict against a
     parisc cleanup, the solution is to use their new version.

   - The nds32 architecture ends its tenure in the Linux kernel.

     The hardware is still used and the code is in reasonable shape, but
     the mainline port is not actively maintained any more, as all
     remaining users are thought to run vendor kernels that would never
     be updated to a future release.

   - A series from Masahiro Yamada cleans up some of the uapi header
     files to pass the compile-time checks"

* tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits)
  nds32: Remove the architecture
  uaccess: remove CONFIG_SET_FS
  ia64: remove CONFIG_SET_FS support
  sh: remove CONFIG_SET_FS support
  sparc64: remove CONFIG_SET_FS support
  lib/test_lockup: fix kernel pointer check for separate address spaces
  uaccess: generalize access_ok()
  uaccess: fix type mismatch warnings from access_ok()
  arm64: simplify access_ok()
  m68k: fix access_ok for coldfire
  MIPS: use simpler access_ok()
  MIPS: Handle address errors for accesses above CPU max virtual user address
  uaccess: add generic __{get,put}_kernel_nofault
  nios2: drop access_ok() check from __put_user()
  x86: use more conventional access_ok() definition
  x86: remove __range_not_ok()
  sparc64: add __{get,put}_kernel_nofault()
  nds32: fix access_ok() checks in get/put_user
  uaccess: fix nios2 and microblaze get_user_8()
  sparc64: fix building assembly files
  ...
2022-03-23 18:03:08 -07:00
Sagar Patel
ee94b5a061 arm64: drop unused includes of <linux/personality.h>
Drop several includes of <linux/personality.h> which are not used.
git-blame indicates they were used at some point, but they're not needed
anymore.

Signed-off-by: Sagar Patel <sagarmp@cs.unc.edu>
Link: https://lore.kernel.org/r/20220307222412.146506-1-sagarmp@cs.unc.edu
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08 10:23:42 +00:00
Arnd Bergmann
967747bbc0 uaccess: remove CONFIG_SET_FS
There are no remaining callers of set_fs(), so CONFIG_SET_FS
can be removed globally, along with the thread_info field and
any references to it.

This turns access_ok() into a cheaper check against TASK_SIZE_MAX.

As CONFIG_SET_FS is now gone, drop all remaining references to
set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel().

Acked-by: Sam Ravnborg <sam@ravnborg.org> # for sparc32 changes
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Tested-by: Sergey Matyukevich <sergey.matyukevich@synopsys.com> # for arc changes
Acked-by: Stafford Horne <shorne@gmail.com> # [openrisc, asm-generic]
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-25 09:36:06 +01:00
Linus Torvalds
35ce8ae9ae Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull signal/exit/ptrace updates from Eric Biederman:
 "This set of changes deletes some dead code, makes a lot of cleanups
  which hopefully make the code easier to follow, and fixes bugs found
  along the way.

  The end-game which I have not yet reached yet is for fatal signals
  that generate coredumps to be short-circuit deliverable from
  complete_signal, for force_siginfo_to_task not to require changing
  userspace configured signal delivery state, and for the ptrace stops
  to always happen in locations where we can guarantee on all
  architectures that the all of the registers are saved and available on
  the stack.

  Removal of profile_task_ext, profile_munmap, and profile_handoff_task
  are the big successes for dead code removal this round.

  A bunch of small bug fixes are included, as most of the issues
  reported were small enough that they would not affect bisection so I
  simply added the fixes and did not fold the fixes into the changes
  they were fixing.

  There was a bug that broke coredumps piped to systemd-coredump. I
  dropped the change that caused that bug and replaced it entirely with
  something much more restrained. Unfortunately that required some
  rebasing.

  Some successes after this set of changes: There are few enough calls
  to do_exit to audit in a reasonable amount of time. The lifetime of
  struct kthread now matches the lifetime of struct task, and the
  pointer to struct kthread is no longer stored in set_child_tid. The
  flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is
  removed. Issues where task->exit_code was examined with
  signal->group_exit_code should been examined were fixed.

  There are several loosely related changes included because I am
  cleaning up and if I don't include them they will probably get lost.

  The original postings of these changes can be found at:
     https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org

  I trimmed back the last set of changes to only the obviously correct
  once. Simply because there was less time for review than I had hoped"

* 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits)
  ptrace/m68k: Stop open coding ptrace_report_syscall
  ptrace: Remove unused regs argument from ptrace_report_syscall
  ptrace: Remove second setting of PT_SEIZED in ptrace_attach
  taskstats: Cleanup the use of task->exit_code
  exit: Use the correct exit_code in /proc/<pid>/stat
  exit: Fix the exit_code for wait_task_zombie
  exit: Coredumps reach do_group_exit
  exit: Remove profile_handoff_task
  exit: Remove profile_task_exit & profile_munmap
  signal: clean up kernel-doc comments
  signal: Remove the helper signal_group_exit
  signal: Rename group_exit_task group_exec_task
  coredump: Stop setting signal->group_exit_task
  signal: Remove SIGNAL_GROUP_COREDUMP
  signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process
  signal: Make coredump handling explicit in complete_signal
  signal: Have prepare_signal detect coredumps using signal->core_state
  signal: Have the oom killer detect coredumps using signal->core_state
  exit: Move force_uaccess back into do_exit
  exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit
  ...
2022-01-17 05:49:30 +02:00
Eric W. Biederman
0e25498f8c exit: Add and use make_task_dead.
There are two big uses of do_exit.  The first is it's design use to be
the guts of the exit(2) system call.  The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.

Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure.  In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.

Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.

As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-12-13 12:04:45 -06:00
Russell King
b89ddf4cca arm64/bpf: Remove 128MB limit for BPF JIT programs
Commit 91fc957c9b ("arm64/bpf: don't allocate BPF JIT programs in module
memory") restricts BPF JIT program allocation to a 128MB region to ensure
BPF programs are still in branching range of each other. However this
restriction should not apply to the aarch64 JIT, since BPF_JMP | BPF_CALL
are implemented as a 64-bit move into a register and then a BLR instruction -
which has the effect of being able to call anything without proximity
limitation.

The practical reason to relax this restriction on JIT memory is that 128MB of
JIT memory can be quickly exhausted, especially where PAGE_SIZE is 64KB - one
page is needed per program. In cases where seccomp filters are applied to
multiple VMs on VM launch - such filters are classic BPF but converted to
BPF - this can severely limit the number of VMs that can be launched. In a
world where we support BPF JIT always on, turning off the JIT isn't always an
option either.

Fixes: 91fc957c9b ("arm64/bpf: don't allocate BPF JIT programs in module memory")
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <russell.king@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/1636131046-5982-2-git-send-email-alan.maguire@oracle.com
2021-11-08 22:16:26 +01:00
Will Deacon
2bc655ce29 Merge branch 'for-next/misc' into for-next/core
* for-next/misc:
  arm64: Select POSIX_CPU_TIMERS_TASK_WORK
  arm64: Document boot requirements for FEAT_SME_FA64
  arm64: ftrace: use function_nocfi for _mcount as well
  arm64: asm: setup.h: export common variables
  arm64/traps: Avoid unnecessary kernel/user pointer conversion
2021-10-29 12:24:59 +01:00
Will Deacon
99fe09c857 Merge branch 'for-next/extable' into for-next/core
* for-next/extable:
  arm64: vmlinux.lds.S: remove `.fixup` section
  arm64: extable: add load_unaligned_zeropad() handler
  arm64: extable: add a dedicated uaccess handler
  arm64: extable: add `type` and `data` fields
  arm64: extable: use `ex` for `exception_table_entry`
  arm64: extable: make fixup_exception() return bool
  arm64: extable: consolidate definitions
  arm64: gpr-num: support W registers
  arm64: factor out GPR numbering helpers
  arm64: kvm: use kvm_exception_table_entry
  arm64: lib: __arch_copy_to_user(): fold fixups into body
  arm64: lib: __arch_copy_from_user(): fold fixups into body
  arm64: lib: __arch_clear_user(): fold fixups into body
2021-10-29 12:24:37 +01:00
Mark Rutland
2e77a62cb3 arm64: extable: add a dedicated uaccess handler
For inline assembly, we place exception fixups out-of-line in the
`.fixup` section such that these are out of the way of the fast path.
This has a few drawbacks:

* Since the fixup code is anonymous, backtraces will symbolize fixups as
  offsets from the nearest prior symbol, currently
  `__entry_tramp_text_end`. This is confusing, and painful to debug
  without access to the relevant vmlinux.

* Since the exception handler adjusts the PC to execute the fixup, and
  the fixup uses a direct branch back into the function it fixes,
  backtraces of fixups miss the original function. This is confusing,
  and violates requirements for RELIABLE_STACKTRACE (and therefore
  LIVEPATCH).

* Inline assembly and associated fixups are generated from templates,
  and we have many copies of logically identical fixups which only
  differ in which specific registers are written to and which address is
  branched to at the end of the fixup. This is potentially wasteful of
  I-cache resources, and makes it hard to add additional logic to fixups
  without significant bloat.

This patch address all three concerns for inline uaccess fixups by
adding a dedicated exception handler which updates registers in
exception context and subsequent returns back into the function which
faulted, removing the need for fixups specialized to each faulting
instruction.

Other than backtracing, there should be no functional change as a result
of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20211019160219.5202-12-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-21 10:45:22 +01:00
Marc Zyngier
ae976f063b arm64: Add handling of CNTVCTSS traps
Since CNTVCTSS obey the same control bits as CNTVCT, add the necessary
decoding to the hook table. Note that there is no known user of
this at the moment.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-17-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-19 10:56:20 +01:00
Amit Daniel Kachhap
f5b650f887 arm64/traps: Avoid unnecessary kernel/user pointer conversion
Annotating a pointer from kernel to __user and then back again requires
an extra __force annotation to silent sparse warning. In call_undef_hook()
this unnecessary complexity can be avoided by modifying the intermediate
user pointer to unsigned long.

This way there is no inter-changeable use of user and kernel pointers
and the code is consistent.

Note: This patch adds no functional changes to code.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210917055811.22341-1-amit.kachhap@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-09-29 16:44:20 +01:00
Will Deacon
181a126979 Merge branch 'for-next/insn' into for-next/core
Refactoring of our instruction decoding routines and addition of some
missing encodings.

* for-next/insn:
  arm64: insn: avoid circular include dependency
  arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>
  arm64: insn: decouple patching from insn code
  arm64: insn: Add load/store decoding helpers
  arm64: insn: Add some opcodes to instruction decoder
  arm64: insn: Add barrier encodings
  arm64: insn: Add SVE instruction class
  arm64: Move instruction encoder/decoder under lib/
  arm64: Move aarch32 condition check functions
  arm64: Move patching utilities out of instruction encoding/decoding
2021-06-24 14:03:24 +01:00
Mark Rutland
3e00e39d9d arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>
For histroical reasons, we define AARCH64_INSN_SIZE in
<asm/alternative-macros.h>, but it would make more sense to do so in
<asm/insn.h>. Let's move it into <asm/insn.h>, and add the necessary
include directives for this.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210609102301.17332-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-11 11:19:27 +01:00
Mark Rutland
78b92c7337 arm64: insn: decouple patching from insn code
Currently, <asm/insn.h> includes <asm/patching.h>. We intend that
<asm/insn.h> will be usable from userspace, so it doesn't make sense to
include headers for kernel-only features such as the patching routines,
and we'd intended to restrict <asm/insn.h> to instruction encoding
details.

Let's decouple the patching code from <asm/insn.h>, and explicitly
include <asm/patching.h> where it is needed. Since <asm/patching.h>
isn't included from assembly, we can drop the __ASSEMBLY__ guards.

At the same time, sort the kprobes includes so that it's easier to see
what is and isn't incldued.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210609102301.17332-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-11 11:19:27 +01:00
Mark Rutland
8168f09886 arm64: entry: split bad stack entry
We'd like to keep all the entry sequencing in entry-common.c, as this
will allow us to ensure this is consistent, and free from any unsound
instrumentation.

Currently handle_bad_stack() performs the NMI entry sequence in traps.c.
Let's split the low-level entry sequence from the reporting, moving the
former to entry-common.c and keeping the latter in traps.c. To make it
clear that reporting function never returns, it is renamed to
panic_bad_stack().

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-17-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07 11:35:56 +01:00
Mark Rutland
ec841aab8d arm64: entry: handle all vectors with C
We have 16 architectural exception vectors, and depending on kernel
configuration we handle 8 or 12 of these with C code, with the remaining
8 or 4 of these handled as special cases in the entry assembly.

It would be nicer if the entry assembly were uniform for all exceptions,
and we deferred any specific handling of the exceptions to C code. This
way the entry assembly can be more easily templated without ifdeffery or
special cases, and it's easier to modify the handling of these cases in
future (e.g. to dump additional registers other context).

This patch reworks the entry code so that we always have a C handler for
every architectural exception vector, with the entry assembly being
completely uniform. We now have to handle exceptions from EL1t and EL1h,
and also have to handle exceptions from AArch32 even when the kernel is
built without CONFIG_COMPAT. To make this clear and to simplify
templating, we rename the top-level exception handlers with a consistent
naming scheme:

  asm: <el+sp>_<regsize>_<type>
  c:   <el+sp>_<regsize>_<type>_handler

.. where:

  <el+sp> is `el1t`, `el1h`, or `el0t`
  <regsize> is `64` or `32`
  <type> is `sync`, `irq`, `fiq`, or `error`

... e.g.

  asm: el1h_64_sync
  c:   el1h_64_sync_handler

... with lower-level handlers simply using "el1" and "compat" as today.

For unexpected exceptions, this information is passed to
__panic_unhandled(), so it can report the specific vector an unexpected
exception was taken from, e.g.

| Unhandled 64-bit el1t sync exception

For vectors we never expect to enter legitimately, the C code is
generated using a macro to avoid code duplication. The exceptions are
handled via __panic_unhandled(), replacing bad_mode() (which is
removed).

The `kernel_ventry` and `entry_handler` assembly macros are updated to
handle the new naming scheme. In theory it should be possible to
generate the entry functions at the same time as the vectors using a
single table, but this will require reworking the linker script to split
the two into separate sections, so for now we have separate tables.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-15-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07 11:35:55 +01:00
Mark Rutland
cbed5f8d3f arm64: entry: move bad_mode() to entry-common.c
In subsequent patches we'll rework the way bad_mode() is called by
exception entry code. In preparation for this, let's move bad_mode()
itself into entry-common.c.

Let's also mark it as noinstr (e.g. to prevent it being kprobed), and
let's also make the `handler` array a local variable, as this is only
use by bad_mode(), and will be removed entirely in a subsequent patch.

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>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-12-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07 11:35:55 +01:00
Mark Rutland
bb8e93a287 arm64: entry: convert SError handlers to C
For various reasons we'd like to convert the bulk of arm64's exception
triage logic to C. As a step towards that, this patch converts the EL1
and EL0 SError triage logic to C.

Separate C functions are added for the native and compat cases so that
in subsequent patches we can handle native/compat differences in C.

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>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-4-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07 11:35:54 +01:00
Mark Rutland
382dcdd66c arm64: remove redundant local_daif_mask() in bad_mode()
Upon taking an exception, the CPU sets all the DAIF bits. We never
clear any of these bits prior to calling bad_mode(), and bad_mode()
itself never clears any of these bits, so there's no need to call
local_daif_mask().

This patch removes the redundant call.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-07 11:35:54 +01:00
Julien Thierry
633e5e938f arm64: Move aarch32 condition check functions
The functions to check condition flags for aarch32 execution is only
used to emulate aarch32 instructions. Move them from the instruction
encoding/decoding code to the trap handling files.

Signed-off-by: Julien Thierry <jthierry@redhat.com>
Link: https://lore.kernel.org/r/20210303170536.1838032-3-jthierry@redhat.com
[will: leave aarch32_opcode_cond_checks where it is]
Signed-off-by: Will Deacon <will@kernel.org>

Signed-off-by: Will Deacon <will@kernel.org>
2021-05-27 17:38:07 +01:00
Zhiyuan Dai
d9f1b52afa arm64: improve whitespace
In a few places we don't have whitespace between macro parameters,
which makes them hard to read. This patch adds whitespace to clearly
separate the parameters.

In a few places we have unnecessary whitespace around unary operators,
which is confusing, This patch removes the unnecessary whitespace.

Signed-off-by: Zhiyuan Dai <daizhiyuan@phytium.com.cn>
Link: https://lore.kernel.org/r/1612403029-5011-1-git-send-email-daizhiyuan@phytium.com.cn
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-04 13:59:49 +00:00
Tian Tao
3fb6819f41 arm64: traps: remove duplicate include statement
asm/exception.h is included more than once. Remove the one that isn't
necessary.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/1609139108-10819-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-01-05 17:52:12 +00:00
Catalin Marinas
d889797530 Merge remote-tracking branch 'arm64/for-next/fixes' into for-next/core
* arm64/for-next/fixes: (26 commits)
  arm64: mte: fix prctl(PR_GET_TAGGED_ADDR_CTRL) if TCF0=NONE
  arm64: mte: Fix typo in macro definition
  arm64: entry: fix EL1 debug transitions
  arm64: entry: fix NMI {user, kernel}->kernel transitions
  arm64: entry: fix non-NMI kernel<->kernel transitions
  arm64: ptrace: prepare for EL1 irq/rcu tracking
  arm64: entry: fix non-NMI user<->kernel transitions
  arm64: entry: move el1 irq/nmi logic to C
  arm64: entry: prepare ret_to_user for function call
  arm64: entry: move enter_from_user_mode to entry-common.c
  arm64: entry: mark entry code as noinstr
  arm64: mark idle code as noinstr
  arm64: syscall: exit userspace before unmasking exceptions
  arm64: pgtable: Ensure dirty bit is preserved across pte_wrprotect()
  arm64: pgtable: Fix pte_accessible()
  ACPI/IORT: Fix doc warnings in iort.c
  arm64/fpsimd: add <asm/insn.h> to <asm/kprobes.h> to fix fpsimd build
  arm64: cpu_errata: Apply Erratum 845719 to KRYO2XX Silver
  arm64: proton-pack: Add KRYO2XX silver CPUs to spectre-v2 safe-list
  arm64: kpti: Add KRYO2XX gold/silver CPU cores to kpti safelist
  ...

# Conflicts:
#	arch/arm64/include/asm/exception.h
#	arch/arm64/kernel/sdei.c
2020-12-09 18:04:55 +00:00
Mark Rutland
f0cd5ac1e4 arm64: entry: fix NMI {user, kernel}->kernel transitions
Exceptions which can be taken at (almost) any time are consdiered to be
NMIs. On arm64 that includes:

* SDEI events
* GICv3 Pseudo-NMIs
* Kernel stack overflows
* Unexpected/unhandled exceptions

... but currently debug exceptions (BRKs, breakpoints, watchpoints,
single-step) are not considered NMIs.

As these can be taken at any time, kernel features (lockdep, RCU,
ftrace) may not be in a consistent kernel state. For example, we may
take an NMI from the idle code or partway through an entry/exit path.

While nmi_enter() and nmi_exit() handle most of this state, notably they
don't save/restore the lockdep state across an NMI being taken and
handled. When interrupts are enabled and an NMI is taken, lockdep may
see interrupts become disabled within the NMI code, but not see
interrupts become enabled when returning from the NMI, leaving lockdep
believing interrupts are disabled when they are actually disabled.

The x86 code handles this in idtentry_{enter,exit}_nmi(), which will
shortly be moved to the generic entry code. As we can't use either yet,
we copy the x86 approach in arm64-specific helpers. All the NMI
entrypoints are marked as noinstr to prevent any instrumentation
handling code being invoked before the state has been corrected.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201130115950.22492-11-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-11-30 12:11:38 +00:00
Mark Rutland
2f911d494f arm64: entry: move enter_from_user_mode to entry-common.c
In later patches we'll want to extend enter_from_user_mode() and add a
corresponding exit_to_user_mode(). As these will be common for all
entries/exits from userspace, it'd be better for these to live in
entry-common.c with the rest of the entry logic.

This patch moves enter_from_user_mode() into entry-common.c. As with
other functions in entry-common.c it is marked as noinstr (which
prevents all instrumentation, tracing, and kprobes) but there are no
other functional changes.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201130115950.22492-5-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-11-30 12:11:37 +00:00
Peter Collingbourne
dceec3ff78 arm64: expose FAR_EL1 tag bits in siginfo
The kernel currently clears the tag bits (i.e. bits 56-63) in the fault
address exposed via siginfo.si_addr and sigcontext.fault_address. However,
the tag bits may be needed by tools in order to accurately diagnose
memory errors, such as HWASan [1] or future tools based on the Memory
Tagging Extension (MTE).

Expose these bits via the arch_untagged_si_addr mechanism, so that
they are only exposed to signal handlers with the SA_EXPOSE_TAGBITS
flag set.

[1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html

Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://linux-review.googlesource.com/id/Ia8876bad8c798e0a32df7c2ce1256c4771c81446
Link: https://lore.kernel.org/r/0010296597784267472fa13b39f8238d87a72cf8.1605904350.git.pcc@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-11-23 18:17:39 +00:00
Will Deacon
57b8b1b435 Merge branches 'for-next/acpi', 'for-next/boot', 'for-next/bpf', 'for-next/cpuinfo', 'for-next/fpsimd', 'for-next/misc', 'for-next/mm', 'for-next/pci', 'for-next/perf', 'for-next/ptrauth', 'for-next/sdei', 'for-next/selftests', 'for-next/stacktrace', 'for-next/svm', 'for-next/topology', 'for-next/tpyos' and 'for-next/vdso' into for-next/core
Remove unused functions and parameters from ACPI IORT code.
(Zenghui Yu via Lorenzo Pieralisi)
* for-next/acpi:
  ACPI/IORT: Remove the unused inline functions
  ACPI/IORT: Drop the unused @ops of iort_add_device_replay()

Remove redundant code and fix documentation of caching behaviour for the
HVC_SOFT_RESTART hypercall.
(Pingfan Liu)
* for-next/boot:
  Documentation/kvm/arm: improve description of HVC_SOFT_RESTART
  arm64/relocate_kernel: remove redundant code

Improve reporting of unexpected kernel traps due to BPF JIT failure.
(Will Deacon)
* for-next/bpf:
  arm64: Improve diagnostics when trapping BRK with FAULT_BRK_IMM

Improve robustness of user-visible HWCAP strings and their corresponding
numerical constants.
(Anshuman Khandual)
* for-next/cpuinfo:
  arm64/cpuinfo: Define HWCAP name arrays per their actual bit definitions

Cleanups to handling of SVE and FPSIMD register state in preparation
for potential future optimisation of handling across syscalls.
(Julien Grall)
* for-next/fpsimd:
  arm64/sve: Implement a helper to load SVE registers from FPSIMD state
  arm64/sve: Implement a helper to flush SVE registers
  arm64/fpsimdmacros: Allow the macro "for" to be used in more cases
  arm64/fpsimdmacros: Introduce a macro to update ZCR_EL1.LEN
  arm64/signal: Update the comment in preserve_sve_context
  arm64/fpsimd: Update documentation of do_sve_acc

Miscellaneous changes.
(Tian Tao and others)
* for-next/misc:
  arm64/mm: return cpu_all_mask when node is NUMA_NO_NODE
  arm64: mm: Fix missing-prototypes in pageattr.c
  arm64/fpsimd: Fix missing-prototypes in fpsimd.c
  arm64: hibernate: Remove unused including <linux/version.h>
  arm64/mm: Refactor {pgd, pud, pmd, pte}_ERROR()
  arm64: Remove the unused include statements
  arm64: get rid of TEXT_OFFSET
  arm64: traps: Add str of description to panic() in die()

Memory management updates and cleanups.
(Anshuman Khandual and others)
* for-next/mm:
  arm64: dbm: Invalidate local TLB when setting TCR_EL1.HD
  arm64: mm: Make flush_tlb_fix_spurious_fault() a no-op
  arm64/mm: Unify CONT_PMD_SHIFT
  arm64/mm: Unify CONT_PTE_SHIFT
  arm64/mm: Remove CONT_RANGE_OFFSET
  arm64/mm: Enable THP migration
  arm64/mm: Change THP helpers to comply with generic MM semantics
  arm64/mm/ptdump: Add address markers for BPF regions

Allow prefetchable PCI BARs to be exposed to userspace using normal
non-cacheable mappings.
(Clint Sbisa)
* for-next/pci:
  arm64: Enable PCI write-combine resources under sysfs

Perf/PMU driver updates.
(Julien Thierry and others)
* for-next/perf:
  perf: arm-cmn: Fix conversion specifiers for node type
  perf: arm-cmn: Fix unsigned comparison to less than zero
  arm_pmu: arm64: Use NMIs for PMU
  arm_pmu: Introduce pmu_irq_ops
  KVM: arm64: pmu: Make overflow handler NMI safe
  arm64: perf: Defer irq_work to IPI_IRQ_WORK
  arm64: perf: Remove PMU locking
  arm64: perf: Avoid PMXEV* indirection
  arm64: perf: Add missing ISB in armv8pmu_enable_counter()
  perf: Add Arm CMN-600 PMU driver
  perf: Add Arm CMN-600 DT binding
  arm64: perf: Add support caps under sysfs
  drivers/perf: thunderx2_pmu: Fix memory resource error handling
  drivers/perf: xgene_pmu: Fix uninitialized resource struct
  perf: arm_dsu: Support DSU ACPI devices
  arm64: perf: Remove unnecessary event_idx check
  drivers/perf: hisi: Add missing include of linux/module.h
  arm64: perf: Add general hardware LLC events for PMUv3

Support for the Armv8.3 Pointer Authentication enhancements.
(By Amit Daniel Kachhap)
* for-next/ptrauth:
  arm64: kprobe: clarify the comment of steppable hint instructions
  arm64: kprobe: disable probe of fault prone ptrauth instruction
  arm64: cpufeature: Modify address authentication cpufeature to exact
  arm64: ptrauth: Introduce Armv8.3 pointer authentication enhancements
  arm64: traps: Allow force_signal_inject to pass esr error code
  arm64: kprobe: add checks for ARMv8.3-PAuth combined instructions

Tonnes of cleanup to the SDEI driver.
(Gavin Shan)
* for-next/sdei:
  firmware: arm_sdei: Remove _sdei_event_unregister()
  firmware: arm_sdei: Remove _sdei_event_register()
  firmware: arm_sdei: Introduce sdei_do_local_call()
  firmware: arm_sdei: Cleanup on cross call function
  firmware: arm_sdei: Remove while loop in sdei_event_unregister()
  firmware: arm_sdei: Remove while loop in sdei_event_register()
  firmware: arm_sdei: Remove redundant error message in sdei_probe()
  firmware: arm_sdei: Remove duplicate check in sdei_get_conduit()
  firmware: arm_sdei: Unregister driver on error in sdei_init()
  firmware: arm_sdei: Avoid nested statements in sdei_init()
  firmware: arm_sdei: Retrieve event number from event instance
  firmware: arm_sdei: Common block for failing path in sdei_event_create()
  firmware: arm_sdei: Remove sdei_is_err()

Selftests for Pointer Authentication and FPSIMD/SVE context-switching.
(Mark Brown and Boyan Karatotev)
* for-next/selftests:
  selftests: arm64: Add build and documentation for FP tests
  selftests: arm64: Add wrapper scripts for stress tests
  selftests: arm64: Add utility to set SVE vector lengths
  selftests: arm64: Add stress tests for FPSMID and SVE context switching
  selftests: arm64: Add test for the SVE ptrace interface
  selftests: arm64: Test case for enumeration of SVE vector lengths
  kselftests/arm64: add PAuth tests for single threaded consistency and differently initialized keys
  kselftests/arm64: add PAuth test for whether exec() changes keys
  kselftests/arm64: add nop checks for PAuth tests
  kselftests/arm64: add a basic Pointer Authentication test

Implementation of ARCH_STACKWALK for unwinding.
(Mark Brown)
* for-next/stacktrace:
  arm64: Move console stack display code to stacktrace.c
  arm64: stacktrace: Convert to ARCH_STACKWALK
  arm64: stacktrace: Make stack walk callback consistent with generic code
  stacktrace: Remove reliable argument from arch_stack_walk() callback

Support for ASID pinning, which is required when sharing page-tables with
the SMMU.
(Jean-Philippe Brucker)
* for-next/svm:
  arm64: cpufeature: Export symbol read_sanitised_ftr_reg()
  arm64: mm: Pin down ASIDs for sharing mm with devices

Rely on firmware tables for establishing CPU topology.
(Valentin Schneider)
* for-next/topology:
  arm64: topology: Stop using MPIDR for topology information

Spelling fixes.
(Xiaoming Ni and Yanfei Xu)
* for-next/tpyos:
  arm64/numa: Fix a typo in comment of arm64_numa_init
  arm64: fix some spelling mistakes in the comments by codespell

vDSO cleanups.
(Will Deacon)
* for-next/vdso:
  arm64: vdso: Fix unusual formatting in *setup_additional_pages()
  arm64: vdso32: Remove a bunch of #ifdef CONFIG_COMPAT_VDSO guards
2020-10-02 12:01:41 +01:00
Mark Brown
9e0f085c2b arm64: Move console stack display code to stacktrace.c
Currently the code for displaying a stack trace on the console is located
in traps.c rather than stacktrace.c, using the unwinding code that is in
stacktrace.c. This can be confusing and make the code hard to find since
such output is often referred to as a stack trace which might mislead the
unwary. Due to this and since traps.c doesn't interact with this code
except for via the public interfaces move the code to stacktrace.c to
make it easier to find.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200921122341.11280-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-21 19:43:03 +01:00
Will Deacon
0fdb64c2a3 arm64: Improve diagnostics when trapping BRK with FAULT_BRK_IMM
When generating instructions at runtime, for example due to kernel text
patching or the BPF JIT, we can emit a trapping BRK instruction if we
are asked to encode an invalid instruction such as an out-of-range]
branch. This is indicative of a bug in the caller, and will result in a
crash on executing the generated code. Unfortunately, the message from
the crash is really unhelpful, and mumbles something about ptrace:

  | Unexpected kernel BRK exception at EL1
  | Internal error: ptrace BRK handler: f2000100 [#1] SMP

We can do better than this. Install a break handler for FAULT_BRK_IMM,
which is the immediate used to encode the "I've been asked to generate
an invalid instruction" error, and triage the faulting PC to determine
whether or not the failure occurred in the BPF JIT.

Link: https://lore.kernel.org/r/20200915141707.GB26439@willie-the-truck
Reported-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-18 16:35:54 +01:00
Gavin Shan
2cf660eb81 arm64/mm: Refactor {pgd, pud, pmd, pte}_ERROR()
The function __{pgd, pud, pmd, pte}_error() are introduced so that
they can be called by {pgd, pud, pmd, pte}_ERROR(). However, some
of the functions could never be called when the corresponding page
table level isn't enabled. For example, __{pud, pmd}_error() are
unused when PUD and PMD are folded to PGD.

This removes __{pgd, pud, pmd, pte}_error() and call pr_err() from
{pgd, pud, pmd, pte}_ERROR() directly, similar to what x86/powerpc
are doing. With this, the code looks a bit simplified either.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20200913234730.23145-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-14 13:23:41 +01:00
Amit Daniel Kachhap
e16aeb0726 arm64: ptrauth: Introduce Armv8.3 pointer authentication enhancements
Some Armv8.3 Pointer Authentication enhancements have been introduced
which are mandatory for Armv8.6 and optional for Armv8.3. These features
are,

* ARMv8.3-PAuth2 - An enhanced PAC generation logic is added which hardens
  finding the correct PAC value of the authenticated pointer.

* ARMv8.3-FPAC - Fault is generated now when the ptrauth authentication
  instruction fails in authenticating the PAC present in the address.
  This is different from earlier case when such failures just adds an
  error code in the top byte and waits for subsequent load/store to abort.
  The ptrauth instructions which may cause this fault are autiasp, retaa
  etc.

The above features are now represented by additional configurations
for the Address Authentication cpufeature and a new ESR exception class.

The userspace fault received in the kernel due to ARMv8.3-FPAC is treated
as Illegal instruction and hence signal SIGILL is injected with ILL_ILLOPN
as the signal code. Note that this is different from earlier ARMv8.3
ptrauth where signal SIGSEGV is issued due to Pointer authentication
failures. The in-kernel PAC fault causes kernel to crash.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20200914083656.21428-4-amit.kachhap@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-14 12:07:02 +01:00
Amit Daniel Kachhap
4ef333b2d1 arm64: traps: Allow force_signal_inject to pass esr error code
Some error signal need to pass proper ARM esr error code to userspace to
better identify the cause of the signal. So the function
force_signal_inject is extended to pass this as a parameter. The
existing code is not affected by this change.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Link: https://lore.kernel.org/r/20200914083656.21428-3-amit.kachhap@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-14 12:07:02 +01:00
Yue Hu
b4c9712459 arm64: traps: Add str of description to panic() in die()
Currently, there are different description strings in die() such as
die("Oops",,), die("Oops - BUG",,). And panic() called by die() will
always show "Fatal exception" or "Fatal exception in interrupt".

Note that panic() will run any panic handler via panic_notifier_list.
And the string above will be formatted and placed in static buf[]
which will be passed to handler.

So panic handler can not distinguish which Oops it is from the buf if
we want to do some things like reserve the string in memory or panic
statistics. It's not benefit to debug. We need to add more codes to
troubleshoot. Let's utilize existing resource to make debug much simpler.

Signed-off-by: Yue Hu <huyue2@yulong.com>
Link: https://lore.kernel.org/r/20200804085347.10720-1-zbestahu@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-07 11:39:56 +01:00
Maninder Singh
338c11e94e arm64: use IRQ_STACK_SIZE instead of THREAD_SIZE for irq stack
IRQ_STACK_SIZE can be made different from THREAD_SIZE,
and as IRQ_STACK_SIZE is used while irq stack allocation,
same define should be used while printing information of irq stack.

Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1596196190-14141-1-git-send-email-maninder1.s@samsung.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-31 18:05:36 +01:00
Linus Torvalds
84bc1993e2 arm64 fixes for -rc2
- Fix handling of watchpoints triggered by uaccess routines
 
 - Fix initialisation of gigantic pages for CMA buffers
 
 - Raise minimum clang version for BTI to avoid miscompilation
 
 - Fix data race in SVE vector length configuration code
 
 - Ensure address tags are ignored in kern_addr_valid()
 
 - Dump register state on fatal BTI exception
 
 - kexec_file() cleanup to use struct_size() macro
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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:
 "Unfortunately, we still have a number of outstanding issues so there
  will be more fixes to come, but this lot are a good start.

   - Fix handling of watchpoints triggered by uaccess routines

   - Fix initialisation of gigantic pages for CMA buffers

   - Raise minimum clang version for BTI to avoid miscompilation

   - Fix data race in SVE vector length configuration code

   - Ensure address tags are ignored in kern_addr_valid()

   - Dump register state on fatal BTI exception

   - kexec_file() cleanup to use struct_size() macro"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: hw_breakpoint: Don't invoke overflow handler on uaccess watchpoints
  arm64: kexec_file: Use struct_size() in kmalloc()
  arm64: mm: reserve hugetlb CMA after numa_init
  arm64: bti: Require clang >= 10.0.1 for in-kernel BTI support
  arm64: sve: Fix build failure when ARM64_SVE=y and SYSCTL=n
  arm64: pgtable: Clear the GP bit for non-executable kernel pages
  arm64: mm: reset address tag set by kasan sw tagging
  arm64: traps: Dump registers prior to panic() in bad_mode()
  arm64/sve: Eliminate data races on sve_default_vl
  docs/arm64: Fix typo'd #define in sve.rst
  arm64: remove TEXT_OFFSET randomization
2020-06-19 12:19:12 -07:00
Christoph Hellwig
25f12ae45f maccess: rename probe_kernel_address to get_kernel_nofault
Better describe what this helper does, and match the naming of
copy_from_kernel_nofault.

Also switch the argument order around, so that it acts and looks
like get_user().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-18 11:14:40 -07:00
Will Deacon
413d3ea6b7 arm64: traps: Dump registers prior to panic() in bad_mode()
When panicing due to an unknown/unhandled exception at EL1, dump the
registers of the faulting context so that it's easier to figure out
what went wrong. In particular, this makes it a lot easier to debug
in-kernel BTI failures since it pretty-prints PSTATE.BTYPE in the crash
log.

Cc: Mark Brown <broonie@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200615113458.2884-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-15 16:58:13 +01:00
Michel Lespinasse
d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Dmitry Safonov
9cb8f069de kernel: rename show_stack_loglvl() => show_stack()
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov
c0fe096a8a arm64: add show_stack_loglvl()
Currently, the log-level of show_stack() depends on a platform
realization.  It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).

Furthermore, it forces the logic decision from user to an architecture
side.  In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages.  And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.

Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers.  Also, it will consolidate
printings with headers.

Introduce show_stack_loglvl(), that eventually will substitute
show_stack().

[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-11-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:11 -07:00
Dmitry Safonov
c76898373f arm64: add loglvl to dump_backtrace()
Currently, the log-level of show_stack() depends on a platform
realization.  It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).

Furthermore, it forces the logic decision from user to an architecture
side.  In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages.  And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.

Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers.  Also, it will consolidate
printings with headers.

Add log level argument to dump_backtrace() as a preparation for
introducing show_stack_loglvl().

[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-10-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:11 -07:00
Linus Torvalds
533b220f7b arm64 updates for 5.8
- Branch Target Identification (BTI)
 	* Support for ARMv8.5-BTI in both user- and kernel-space. This
 	  allows branch targets to limit the types of branch from which
 	  they can be called and additionally prevents branching to
 	  arbitrary code, although kernel support requires a very recent
 	  toolchain.
 
 	* Function annotation via SYM_FUNC_START() so that assembly
 	  functions are wrapped with the relevant "landing pad"
 	  instructions.
 
 	* BPF and vDSO updates to use the new instructions.
 
 	* Addition of a new HWCAP and exposure of BTI capability to
 	  userspace via ID register emulation, along with ELF loader
 	  support for the BTI feature in .note.gnu.property.
 
 	* Non-critical fixes to CFI unwind annotations in the sigreturn
 	  trampoline.
 
 - Shadow Call Stack (SCS)
 	* Support for Clang's Shadow Call Stack feature, which reserves
 	  platform register x18 to point at a separate stack for each
 	  task that holds only return addresses. This protects function
 	  return control flow from buffer overruns on the main stack.
 
 	* Save/restore of x18 across problematic boundaries (user-mode,
 	  hypervisor, EFI, suspend, etc).
 
 	* Core support for SCS, should other architectures want to use it
 	  too.
 
 	* SCS overflow checking on context-switch as part of the existing
 	  stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
 
 - CPU feature detection
 	* Removed numerous "SANITY CHECK" errors when running on a system
 	  with mismatched AArch32 support at EL1. This is primarily a
 	  concern for KVM, which disabled support for 32-bit guests on
 	  such a system.
 
 	* Addition of new ID registers and fields as the architecture has
 	  been extended.
 
 - Perf and PMU drivers
 	* Minor fixes and cleanups to system PMU drivers.
 
 - Hardware errata
 	* Unify KVM workarounds for VHE and nVHE configurations.
 
 	* Sort vendor errata entries in Kconfig.
 
 - Secure Monitor Call Calling Convention (SMCCC)
 	* Update to the latest specification from Arm (v1.2).
 
 	* Allow PSCI code to query the SMCCC version.
 
 - Software Delegated Exception Interface (SDEI)
 	* Unexport a bunch of unused symbols.
 
 	* Minor fixes to handling of firmware data.
 
 - Pointer authentication
 	* Add support for dumping the kernel PAC mask in vmcoreinfo so
 	  that the stack can be unwound by tools such as kdump.
 
 	* Simplification of key initialisation during CPU bringup.
 
 - BPF backend
 	* Improve immediate generation for logical and add/sub
 	  instructions.
 
 - vDSO
 	- Minor fixes to the linker flags for consistency with other
 	  architectures and support for LLVM's unwinder.
 
 	- Clean up logic to initialise and map the vDSO into userspace.
 
 - ACPI
 	- Work around for an ambiguity in the IORT specification relating
 	  to the "num_ids" field.
 
 	- Support _DMA method for all named components rather than only
 	  PCIe root complexes.
 
 	- Minor other IORT-related fixes.
 
 - Miscellaneous
 	* Initialise debug traps early for KGDB and fix KDB cacheflushing
 	  deadlock.
 
 	* Minor tweaks to early boot state (documentation update, set
 	  TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
 
 	* Refactoring and cleanup
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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:
 "A sizeable pile of arm64 updates for 5.8.

  Summary below, but the big two features are support for Branch Target
  Identification and Clang's Shadow Call stack. The latter is currently
  arm64-only, but the high-level parts are all in core code so it could
  easily be adopted by other architectures pending toolchain support

  Branch Target Identification (BTI):

   - Support for ARMv8.5-BTI in both user- and kernel-space. This allows
     branch targets to limit the types of branch from which they can be
     called and additionally prevents branching to arbitrary code,
     although kernel support requires a very recent toolchain.

   - Function annotation via SYM_FUNC_START() so that assembly functions
     are wrapped with the relevant "landing pad" instructions.

   - BPF and vDSO updates to use the new instructions.

   - Addition of a new HWCAP and exposure of BTI capability to userspace
     via ID register emulation, along with ELF loader support for the
     BTI feature in .note.gnu.property.

   - Non-critical fixes to CFI unwind annotations in the sigreturn
     trampoline.

  Shadow Call Stack (SCS):

   - Support for Clang's Shadow Call Stack feature, which reserves
     platform register x18 to point at a separate stack for each task
     that holds only return addresses. This protects function return
     control flow from buffer overruns on the main stack.

   - Save/restore of x18 across problematic boundaries (user-mode,
     hypervisor, EFI, suspend, etc).

   - Core support for SCS, should other architectures want to use it
     too.

   - SCS overflow checking on context-switch as part of the existing
     stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.

  CPU feature detection:

   - Removed numerous "SANITY CHECK" errors when running on a system
     with mismatched AArch32 support at EL1. This is primarily a concern
     for KVM, which disabled support for 32-bit guests on such a system.

   - Addition of new ID registers and fields as the architecture has
     been extended.

  Perf and PMU drivers:

   - Minor fixes and cleanups to system PMU drivers.

  Hardware errata:

   - Unify KVM workarounds for VHE and nVHE configurations.

   - Sort vendor errata entries in Kconfig.

  Secure Monitor Call Calling Convention (SMCCC):

   - Update to the latest specification from Arm (v1.2).

   - Allow PSCI code to query the SMCCC version.

  Software Delegated Exception Interface (SDEI):

   - Unexport a bunch of unused symbols.

   - Minor fixes to handling of firmware data.

  Pointer authentication:

   - Add support for dumping the kernel PAC mask in vmcoreinfo so that
     the stack can be unwound by tools such as kdump.

   - Simplification of key initialisation during CPU bringup.

  BPF backend:

   - Improve immediate generation for logical and add/sub instructions.

  vDSO:

   - Minor fixes to the linker flags for consistency with other
     architectures and support for LLVM's unwinder.

   - Clean up logic to initialise and map the vDSO into userspace.

  ACPI:

   - Work around for an ambiguity in the IORT specification relating to
     the "num_ids" field.

   - Support _DMA method for all named components rather than only PCIe
     root complexes.

   - Minor other IORT-related fixes.

  Miscellaneous:

   - Initialise debug traps early for KGDB and fix KDB cacheflushing
     deadlock.

   - Minor tweaks to early boot state (documentation update, set
     TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).

   - Refactoring and cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
  KVM: arm64: Check advertised Stage-2 page size capability
  arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
  ACPI/IORT: Remove the unused __get_pci_rid()
  arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
  arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
  arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
  arm64/cpufeature: Introduce ID_MMFR5 CPU register
  arm64/cpufeature: Introduce ID_DFR1 CPU register
  arm64/cpufeature: Introduce ID_PFR2 CPU register
  arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
  arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
  arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
  arm64: mm: Add asid_gen_match() helper
  firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
  arm64: vdso: Fix CFI directives in sigreturn trampoline
  arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
  ...
2020-06-01 15:18:27 -07:00
Will Deacon
d27865279f Merge branch 'for-next/bti' into for-next/core
Support for Branch Target Identification (BTI) in user and kernel
(Mark Brown and others)
* for-next/bti: (39 commits)
  arm64: vdso: Fix CFI directives in sigreturn trampoline
  arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
  arm64: bti: Fix support for userspace only BTI
  arm64: kconfig: Update and comment GCC version check for kernel BTI
  arm64: vdso: Map the vDSO text with guarded pages when built for BTI
  arm64: vdso: Force the vDSO to be linked as BTI when built for BTI
  arm64: vdso: Annotate for BTI
  arm64: asm: Provide a mechanism for generating ELF note for BTI
  arm64: bti: Provide Kconfig for kernel mode BTI
  arm64: mm: Mark executable text as guarded pages
  arm64: bpf: Annotate JITed code for BTI
  arm64: Set GP bit in kernel page tables to enable BTI for the kernel
  arm64: asm: Override SYM_FUNC_START when building the kernel with BTI
  arm64: bti: Support building kernel C code using BTI
  arm64: Document why we enable PAC support for leaf functions
  arm64: insn: Report PAC and BTI instructions as skippable
  arm64: insn: Don't assume unrecognized HINTs are skippable
  arm64: insn: Provide a better name for aarch64_insn_is_nop()
  arm64: insn: Add constants for new HINT instruction decode
  arm64: Disable old style assembly annotations
  ...
2020-05-28 18:00:51 +01:00
Peter Zijlstra
69ea03b56e hardirq/nmi: Allow nested nmi_enter()
Since there are already a number of sites (ARM64, PowerPC) that effectively
nest nmi_enter(), make the primitive support this before adding even more.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lkml.kernel.org/r/20200505134100.864179229@linutronix.de
2020-05-19 15:51:17 +02:00
Douglas Anderson
b322c65f8c arm64: Call debug_traps_init() from trap_init() to help early kgdb
A new kgdb feature will soon land (kgdb_earlycon) that lets us run
kgdb much earlier.  In order for everything to work properly it's
important that the break hook is setup by the time we process
"kgdbwait".

Right now the break hook is setup in debug_traps_init() and that's
called from arch_initcall().  That's a bit too late since
kgdb_earlycon really needs things to be setup by the time the system
calls dbg_late_init().

We could fix this by adding call_break_hook() into early_brk64() and
that works fine.  However, it's a little ugly.  Instead, let's just
add a call to debug_traps_init() straight from trap_init().  There's
already a documented dependency between trap_init() and
debug_traps_init() and this makes the dependency more obvious rather
than just relying on a comment.

NOTE: this solution isn't early enough to let us select the
"ARCH_HAS_EARLY_DEBUG" KConfig option that is introduced by the
kgdb_earlycon patch series.  That would only be set if we could do
breakpoints when early params are parsed.  This patch only enables
"late early" breakpoints, AKA breakpoints when dbg_late_init() is
called.  It's expected that this should be fine for most people.

It should also be noted that if you crash you can still end up in kgdb
earlier than debug_traps_init().  Since you don't need breakpoints to
debug a crash that's fine.

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200513160501.1.I0b5edf030cc6ebef6ab4829f8867cdaea42485d8@changeid
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-18 17:51:20 +01:00
Dave Martin
0537c4cd71 arm64: BTI: Reset BTYPE when skipping emulated instructions
Since normal execution of any non-branch instruction resets the
PSTATE BTYPE field to 0, so do the same thing when emulating a
trapped instruction.

Branches don't trap directly, so we should never need to assign a
non-zero value to BTYPE here.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 17:19:49 +00:00
Dave Martin
d2c2ee4cc3 arm64: traps: Shuffle code to eliminate forward declarations
Hoist the IT state handling code earlier in traps.c, to avoid
accumulating forward declarations.

No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 17:19:49 +00:00
Dave Martin
172a797661 arm64: unify native/compat instruction skipping
Skipping of an instruction on AArch32 works a bit differently from
AArch64, mainly due to the different CPSR/PSTATE semantics.

Currently arm64_skip_faulting_instruction() is only suitable for
AArch64, and arm64_compat_skip_faulting_instruction() handles the IT
state machine but is local to traps.c.

Since manual instruction skipping implies a trap, it's a relatively
slow path.

So, make arm64_skip_faulting_instruction() handle both compat and
native, and get rid of the arm64_compat_skip_faulting_instruction()
special case.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 17:19:49 +00:00
Dave Martin
8ef8f360cf arm64: Basic Branch Target Identification support
This patch adds the bare minimum required to expose the ARMv8.5
Branch Target Identification feature to userspace.

By itself, this does _not_ automatically enable BTI for any initial
executable pages mapped by execve().  This will come later, but for
now it should be possible to enable BTI manually on those pages by
using mprotect() from within the target process.

Other arches already using the generic mman.h are already using
0x10 for arch-specific prot flags, so we use that for PROT_BTI
here.

For consistency, signal handler entry points in BTI guarded pages
are required to be annotated as such, just like any other function.
This blocks a relatively minor attack vector, but comforming
userspace will have the annotations anyway, so we may as well
enforce them.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-16 17:19:48 +00:00
Thomas Gleixner
7ef858dad9 sched/rt, arm64: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the Kconfig dependency, entry code and preemption handling over
to use CONFIG_PREEMPTION. Add PREEMPT_RT output in show_stack().

[bigeasy: +traps.c, Kconfig]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20191015191821.11479-3-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08 14:37:32 +01:00
Catalin Marinas
8301ae822d Merge branch 'for-next/entry-s-to-c' into for-next/core
Move the synchronous exception paths from entry.S into a C file to
improve the code readability.

* for-next/entry-s-to-c:
  arm64: entry-common: don't touch daif before bp-hardening
  arm64: Remove asmlinkage from updated functions
  arm64: entry: convert el0_sync to C
  arm64: entry: convert el1_sync to C
  arm64: add local_daif_inherit()
  arm64: Add prototypes for functions called by entry.S
  arm64: remove __exception annotations
2019-10-28 17:02:56 +00:00
James Morse
afa7c0e5b9 arm64: Remove asmlinkage from updated functions
Now that the callers of these functions have moved into C, they no longer
need the asmlinkage annotation. Remove it.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-28 11:22:51 +00:00
James Morse
b6e43c0e31 arm64: remove __exception annotations
Since commit 7326749801 ("arm64: unwind: reference pt_regs via embedded
stack frame") arm64 has not used the __exception annotation to dump
the pt_regs during stack tracing. in_exception_text() has no callers.

This annotation is only used to blacklist kprobes, it means the same as
__kprobes.

Section annotations like this require the functions to be grouped
together between the start/end markers, and placed according to
the linker script. For kprobes we also have NOKPROBE_SYMBOL() which
logs the symbol address in a section that kprobes parses and
blacklists at boot.

Using NOKPROBE_SYMBOL() instead lets kprobes publish the list of
blacklisted symbols, and saves us from having an arm64 specific
spelling of __kprobes.

do_debug_exception() already has a NOKPROBE_SYMBOL() annotation.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-28 11:22:38 +00:00
James Morse
ee9d90be9d arm64: Fake the IminLine size on systems affected by Neoverse-N1 #1542419
Systems affected by Neoverse-N1 #1542419 support DIC so do not need to
perform icache maintenance once new instructions are cleaned to the PoU.
For the errata workaround, the kernel hides DIC from user-space, so that
the unnecessary cache maintenance can be trapped by firmware.

To reduce the number of traps, produce a fake IminLine value based on
PAGE_SIZE.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-25 17:48:44 +01:00
James Morse
05460849c3 arm64: errata: Hide CTR_EL0.DIC on systems affected by Neoverse-N1 #1542419
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: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-10-25 17:46:40 +01:00
Linus Torvalds
e77fafe9af arm64 updates for 5.4:
- 52-bit virtual addressing in the kernel
 
 - New ABI to allow tagged user pointers to be dereferenced by syscalls
 
 - Early RNG seeding by the bootloader
 
 - Improve robustness of SMP boot
 
 - Fix TLB invalidation in light of recent architectural clarifications
 
 - Support for i.MX8 DDR PMU
 
 - Remove direct LSE instruction patching in favour of static keys
 
 - Function error injection using kprobes
 
 - Support for the PPTT "thread" flag introduced by ACPI 6.3
 
 - Move PSCI idle code into proper cpuidle driver
 
 - Relaxation of implicit I/O memory barriers
 
 - Build with RELR relocations when toolchain supports them
 
 - Numerous cleanups and non-critical fixes
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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:
 "Although there isn't tonnes of code in terms of line count, there are
  a fair few headline features which I've noted both in the tag and also
  in the merge commits when I pulled everything together.

  The part I'm most pleased with is that we had 35 contributors this
  time around, which feels like a big jump from the usual small group of
  core arm64 arch developers. Hopefully they all enjoyed it so much that
  they'll continue to contribute, but we'll see.

  It's probably worth highlighting that we've pulled in a branch from
  the risc-v folks which moves our CPU topology code out to where it can
  be shared with others.

  Summary:

   - 52-bit virtual addressing in the kernel

   - New ABI to allow tagged user pointers to be dereferenced by
     syscalls

   - Early RNG seeding by the bootloader

   - Improve robustness of SMP boot

   - Fix TLB invalidation in light of recent architectural
     clarifications

   - Support for i.MX8 DDR PMU

   - Remove direct LSE instruction patching in favour of static keys

   - Function error injection using kprobes

   - Support for the PPTT "thread" flag introduced by ACPI 6.3

   - Move PSCI idle code into proper cpuidle driver

   - Relaxation of implicit I/O memory barriers

   - Build with RELR relocations when toolchain supports them

   - Numerous cleanups and non-critical fixes"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (114 commits)
  arm64: remove __iounmap
  arm64: atomics: Use K constraint when toolchain appears to support it
  arm64: atomics: Undefine internal macros after use
  arm64: lse: Make ARM64_LSE_ATOMICS depend on JUMP_LABEL
  arm64: asm: Kill 'asm/atomic_arch.h'
  arm64: lse: Remove unused 'alt_lse' assembly macro
  arm64: atomics: Remove atomic_ll_sc compilation unit
  arm64: avoid using hard-coded registers for LSE atomics
  arm64: atomics: avoid out-of-line ll/sc atomics
  arm64: Use correct ll/sc atomic constraints
  jump_label: Don't warn on __exit jump entries
  docs/perf: Add documentation for the i.MX8 DDR PMU
  perf/imx_ddr: Add support for AXI ID filtering
  arm64: kpti: ensure patched kernel text is fetched from PoU
  arm64: fix fixmap copy for 16K pages and 48-bit VA
  perf/smmuv3: Validate groups for global filtering
  perf/smmuv3: Validate group size
  arm64: Relax Documentation/arm64/tagged-pointers.rst
  arm64: kvm: Replace hardcoded '1' with SYS_PAR_EL1_F
  arm64: mm: Ignore spurious translation faults taken from the kernel
  ...
2019-09-16 14:31:40 -07:00
James Morse
2671828c3f arm64: entry: Move ct_user_exit before any other exception
When taking an SError or Debug exception from EL0, we run the C
handler for these exceptions before updating the context tracking
code and unmasking lower priority interrupts.

When booting with nohz_full lockdep tells us we got this wrong:
| =============================
| WARNING: suspicious RCU usage
| 5.3.0-rc2-00010-gb4b5e9dcb11b-dirty #11271 Not tainted
| -----------------------------
| include/linux/rcupdate.h:643 rcu_read_unlock() used illegally wh!
|
| other info that might help us debug this:
|
|
| RCU used illegally from idle CPU!
| rcu_scheduler_active = 2, debug_locks = 1
| RCU used illegally from extended quiescent state!
| 1 lock held by a.out/432:
|  #0: 00000000c7a79515 (rcu_read_lock){....}, at: brk_handler+0x00
|
| stack backtrace:
| CPU: 1 PID: 432 Comm: a.out Not tainted 5.3.0-rc2-00010-gb4b5e9d1
| Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno De8
| Call trace:
|  dump_backtrace+0x0/0x140
|  show_stack+0x14/0x20
|  dump_stack+0xbc/0x104
|  lockdep_rcu_suspicious+0xf8/0x108
|  brk_handler+0x164/0x1b0
|  do_debug_exception+0x11c/0x278
|  el0_dbg+0x14/0x20

Moving the ct_user_exit calls to be before do_debug_exception() means
they are also before trace_hardirqs_off() has been updated. Add a new
ct_user_exit_irqoff macro to avoid the context-tracking code using
irqsave/restore before we've updated trace_hardirqs_off(). To be
consistent, do this everywhere.

The C helper is called enter_from_user_mode() to match x86 in the hope
we can merge them into kernel/context_tracking.c later.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 6c81fe7925 ("arm64: enable context tracking")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-21 18:45:52 +01:00
Mark Rutland
37143dcc44 arm64: constify sys64_hook instances
All instances of struct sys64_hook contain compile-time constant data,
and are never inentionally modified, so let's make them all const.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-13 18:32:17 +01:00
Linus Torvalds
7f20fd2337 Bugfixes (arm and x86) and cleanups.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Bugfixes (arm and x86) and cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  selftests: kvm: Adding config fragments
  KVM: selftests: Update gitignore file for latest changes
  kvm: remove unnecessary PageReserved check
  KVM: arm/arm64: vgic: Reevaluate level sensitive interrupts on enable
  KVM: arm: Don't write junk to CP15 registers on reset
  KVM: arm64: Don't write junk to sysregs on reset
  KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block
  x86: kvm: remove useless calls to kvm_para_available
  KVM: no need to check return value of debugfs_create functions
  KVM: remove kvm_arch_has_vcpu_debugfs()
  KVM: Fix leak vCPU's VMCS value into other pCPU
  KVM: Check preempted_in_kernel for involuntary preemption
  KVM: LAPIC: Don't need to wakeup vCPU twice afer timer fire
  arm64: KVM: hyp: debug-sr: Mark expected switch fall-through
  KVM: arm64: Update kvm_arm_exception_class and esr_class_str for new EC
  KVM: arm: vgic-v3: Mark expected switch fall-through
  arm64: KVM: regmap: Fix unexpected switch fall-through
  KVM: arm/arm64: Introduce kvm_pmu_vcpu_init() to setup PMU counter index
2019-08-09 15:46:29 -07:00
Will Deacon
332e5281a4 arm64: esr: Add ESR exception class encoding for trapped ERET
The ESR.EC encoding of 0b011010 (0x1a) describes an exception generated
by an ERET, ERETAA or ERETAB instruction as a result of a nested
virtualisation trap to EL2.

Add an encoding for this EC and a string description so that we identify
it correctly if we take one unexpectedly.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-05 11:06:34 +01:00
Zenghui Yu
6701c619fa KVM: arm64: Update kvm_arm_exception_class and esr_class_str for new EC
We've added two ESR exception classes for new ARM hardware extensions:
ESR_ELx_EC_PAC and ESR_ELx_EC_SVE, but failed to update the strings
used in tracing and other debug.

Let's update "kvm_arm_exception_class" for these two EC, which the
new EC will be visible to user-space via kvm_exit trace events
Also update to "esr_class_str" for ESR_ELx_EC_PAC, by which we can
get more readable debug info.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-07-26 15:40:38 +01:00
Dave Martin
f3dcbe67ed arm64: stacktrace: Factor out backtrace initialisation
Some common code is required by each stacktrace user to initialise
struct stackframe before the first call to unwind_frame().

In preparation for adding to the common code, this patch factors it
out into a separate function start_backtrace(), and modifies the
stacktrace callers appropriately.

No functional change.

Signed-off-by: Dave Martin <dave.martin@arm.com>
[Mark: drop tsk argument, update more callsites]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-07-22 11:44:08 +01:00
Linus Torvalds
39d7530d74 ARM:
* support for chained PMU counters in guests
 * improved SError handling
 * handle Neoverse N1 erratum #1349291
 * allow side-channel mitigation status to be migrated
 * standardise most AArch64 system register accesses to msr_s/mrs_s
 * fix host MPIDR corruption on 32bit
 * selftests ckleanups
 
 x86:
 * PMU event {white,black}listing
 * ability for the guest to disable host-side interrupt polling
 * fixes for enlightened VMCS (Hyper-V pv nested virtualization),
 * new hypercall to yield to IPI target
 * support for passing cstate MSRs through to the guest
 * lots of cleanups and optimizations
 
 Generic:
 * Some txt->rST conversions for the documentation
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - support for chained PMU counters in guests
   - improved SError handling
   - handle Neoverse N1 erratum #1349291
   - allow side-channel mitigation status to be migrated
   - standardise most AArch64 system register accesses to msr_s/mrs_s
   - fix host MPIDR corruption on 32bit
   - selftests ckleanups

  x86:
   - PMU event {white,black}listing
   - ability for the guest to disable host-side interrupt polling
   - fixes for enlightened VMCS (Hyper-V pv nested virtualization),
   - new hypercall to yield to IPI target
   - support for passing cstate MSRs through to the guest
   - lots of cleanups and optimizations

  Generic:
   - Some txt->rST conversions for the documentation"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (128 commits)
  Documentation: virtual: Add toctree hooks
  Documentation: kvm: Convert cpuid.txt to .rst
  Documentation: virtual: Convert paravirt_ops.txt to .rst
  KVM: x86: Unconditionally enable irqs in guest context
  KVM: x86: PMU Event Filter
  kvm: x86: Fix -Wmissing-prototypes warnings
  KVM: Properly check if "page" is valid in kvm_vcpu_unmap
  KVM: arm/arm64: Initialise host's MPIDRs by reading the actual register
  KVM: LAPIC: Retry tune per-vCPU timer_advance_ns if adaptive tuning goes insane
  kvm: LAPIC: write down valid APIC registers
  KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_s
  KVM: doc: Add API documentation on the KVM_REG_ARM_WORKAROUNDS register
  KVM: arm/arm64: Add save/restore support for firmware workaround state
  arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests
  KVM: arm/arm64: Support chained PMU counters
  KVM: arm/arm64: Remove pmc->bitmask
  KVM: arm/arm64: Re-create event when setting counter value
  KVM: arm/arm64: Extract duplicated code to own function
  KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functions
  KVM: LAPIC: ARBPRI is a reserved register for x2APIC
  ...
2019-07-12 15:35:14 -07:00
Linus Torvalds
5ad18b2e60 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
 "A source of error over the years has been that force_sig has taken a
  task parameter when it is only safe to use force_sig with the current
  task.

  The force_sig function is built for delivering synchronous signals
  such as SIGSEGV where the userspace application caused a synchronous
  fault (such as a page fault) and the kernel responded with a signal.

  Because the name force_sig does not make this clear, and because the
  force_sig takes a task parameter the function force_sig has been
  abused for sending other kinds of signals over the years. Slowly those
  have been fixed when the oopses have been tracked down.

  This set of changes fixes the remaining abusers of force_sig and
  carefully rips out the task parameter from force_sig and friends
  making this kind of error almost impossible in the future"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
  signal: Remove the signal number and task parameters from force_sig_info
  signal: Factor force_sig_info_to_task out of force_sig_info
  signal: Generate the siginfo in force_sig
  signal: Move the computation of force into send_signal and correct it.
  signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
  signal: Remove the task parameter from force_sig_fault
  signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
  signal: Explicitly call force_sig_fault on current
  signal/unicore32: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from ptrace_break
  signal/nds32: Remove tsk parameter from send_sigtrap
  signal/riscv: Remove tsk parameter from do_trap
  signal/sh: Remove tsk parameter from force_sig_info_fault
  signal/um: Remove task parameter from send_sigtrap
  signal/x86: Remove task parameter from send_sigtrap
  signal: Remove task parameter from force_sig_mceerr
  signal: Remove task parameter from force_sig
  signal: Remove task parameter from force_sigsegv
  ...
2019-07-08 21:48:15 -07:00
Linus Torvalds
dfd437a257 arm64 updates for 5.3:
- arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}
 
 - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
   manage the permissions of executable vmalloc regions more strictly
 
 - Slight performance improvement by keeping softirqs enabled while
   touching the FPSIMD/SVE state (kernel_neon_begin/end)
 
 - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new XAFLAG
   and AXFLAG instructions for floating point comparison flags
   manipulation) and FRINT (rounding floating point numbers to integers)
 
 - Re-instate ARM64_PSEUDO_NMI support which was previously marked as
   BROKEN due to some bugs (now fixed)
 
 - Improve parking of stopped CPUs and implement an arm64-specific
   panic_smp_self_stop() to avoid warning on not being able to stop
   secondary CPUs during panic
 
 - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
   platforms
 
 - perf: DDR performance monitor support for iMX8QXP
 
 - cache_line_size() can now be set from DT or ACPI/PPTT if provided to
   cope with a system cache info not exposed via the CPUID registers
 
 - Avoid warning on hardware cache line size greater than
   ARCH_DMA_MINALIGN if the system is fully coherent
 
 - arm64 do_page_fault() and hugetlb cleanups
 
 - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)
 
 - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the 'arm_boot_flags'
   introduced in 5.1)
 
 - CONFIG_RANDOMIZE_BASE now enabled in defconfig
 
 - Allow the selection of ARM64_MODULE_PLTS, currently only done via
   RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
   over into the vmalloc area
 
 - Make ZONE_DMA32 configurable
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}

 - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
   manage the permissions of executable vmalloc regions more strictly

 - Slight performance improvement by keeping softirqs enabled while
   touching the FPSIMD/SVE state (kernel_neon_begin/end)

 - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new
   XAFLAG and AXFLAG instructions for floating point comparison flags
   manipulation) and FRINT (rounding floating point numbers to integers)

 - Re-instate ARM64_PSEUDO_NMI support which was previously marked as
   BROKEN due to some bugs (now fixed)

 - Improve parking of stopped CPUs and implement an arm64-specific
   panic_smp_self_stop() to avoid warning on not being able to stop
   secondary CPUs during panic

 - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
   platforms

 - perf: DDR performance monitor support for iMX8QXP

 - cache_line_size() can now be set from DT or ACPI/PPTT if provided to
   cope with a system cache info not exposed via the CPUID registers

 - Avoid warning on hardware cache line size greater than
   ARCH_DMA_MINALIGN if the system is fully coherent

 - arm64 do_page_fault() and hugetlb cleanups

 - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)

 - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the
   'arm_boot_flags' introduced in 5.1)

 - CONFIG_RANDOMIZE_BASE now enabled in defconfig

 - Allow the selection of ARM64_MODULE_PLTS, currently only done via
   RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
   over into the vmalloc area

 - Make ZONE_DMA32 configurable

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits)
  perf: arm_spe: Enable ACPI/Platform automatic module loading
  arm_pmu: acpi: spe: Add initial MADT/SPE probing
  ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens
  ACPI/PPTT: Modify node flag detection to find last IDENTICAL
  x86/entry: Simplify _TIF_SYSCALL_EMU handling
  arm64: rename dump_instr as dump_kernel_instr
  arm64/mm: Drop [PTE|PMD]_TYPE_FAULT
  arm64: Implement panic_smp_self_stop()
  arm64: Improve parking of stopped CPUs
  arm64: Expose FRINT capabilities to userspace
  arm64: Expose ARMv8.5 CondM capability to userspace
  arm64: defconfig: enable CONFIG_RANDOMIZE_BASE
  arm64: ARM64_MODULES_PLTS must depend on MODULES
  arm64: bpf: do not allocate executable memory
  arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages
  arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP
  arm64: module: create module allocations without exec permissions
  arm64: Allow user selection of ARM64_MODULE_PLTS
  acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
  arm64: Allow selecting Pseudo-NMI again
  ...
2019-07-08 09:54:55 -07:00
James Morse
3276cc2489 arm64: Update silicon-errata.txt for Neoverse-N1 #1349291
Neoverse-N1 affected by #1349291 may report an Uncontained RAS Error
as Unrecoverable. The kernel's architecture code already considers
Unrecoverable errors as fatal as without kernel-first support no
further error-handling is possible.

Now that KVM attributes SError to the host/guest more precisely
the host's architecture code will always handle host errors that
become pending during world-switch.
Errors misclassified by this errata that affected the guest will be
re-injected to the guest as an implementation-defined SError, which can
be uncontained.

Until kernel-first support is implemented, no workaround is needed
for this issue.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05 13:03:30 +01:00
jinho lim
7b71665603 arm64: rename dump_instr as dump_kernel_instr
In traps.c, only __die calls dump_instr.
However, this function has sub-function as __dump_instr.

dump_kernel_instr can replace those functions.
By using aarch64_insn_read, it does not have to change fs to KERNEL_DS.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: jinho lim <jordan.lim@samsung.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-06-26 17:59:15 +01:00
Thomas Gleixner
caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Eric W. Biederman
2e1661d267 signal: Remove the task parameter from force_sig_fault
As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from from force_sig_fault to make it explicit that is what is going
on.

The two known exceptions that deliver a synchronous exception to a
stopped ptraced task have already been changed to
force_sig_fault_to_task.

The callers have been changed with the following emacs regular expression
(with obvious variations on the architectures that take more arguments)
to avoid typos:

force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)]
->
force_sig_fault(\1,\2,\3)

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-29 09:31:43 -05:00
Eric W. Biederman
d76cac67db signal/arm64: Use force_sig not force_sig_fault for SIGKILL
I don't think this is userspace visible but SIGKILL does not have
any si_codes that use the fault member of the siginfo union.  Correct
this the simple way and call force_sig instead of force_sig_fault when
the signal is SIGKILL.

The two know places where synchronous SIGKILL are generated are
do_bad_area and fpsimd_save.  The call paths to force_sig_fault are:
do_bad_area
  arm64_force_sig_fault
    force_sig_fault
force_signal_inject
  arm64_notify_die
    arm64_force_sig_fault
       force_sig_fault

Which means correcting this in arm64_force_sig_fault is enough
to ensure the arm64 code is not misusing the generic code, which
could lead to maintenance problems later.

Cc: stable@vger.kernel.org
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Fixes: af40ff687b ("arm64: signal: Ensure si_code is valid for all fault signals")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-05-29 11:05:25 +01:00
Eric W. Biederman
f8eac9011b signal: Remove task parameter from force_sig_mceerr
All of the callers pass current into force_sig_mceer so remove the
task parameter to make this obvious.

This also makes it clear that force_sig_mceerr passes current
into force_sig_info.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-27 09:36:28 -05:00
Eric W. Biederman
3cf5d076fb signal: Remove task parameter from force_sig
All of the remaining callers pass current into force_sig so
remove the task parameter to make this obvious and to make
misuse more difficult in the future.

This also makes it clear force_sig passes current into force_sig_info.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-27 09:36:28 -05:00
Eric W. Biederman
82e10af224 signal/arm64: Use force_sig not force_sig_fault for SIGKILL
I don't think this is userspace visible but SIGKILL does not have
any si_codes that use the fault member of the siginfo union.  Correct
this the simple way and call force_sig instead of force_sig_fault when
the signal is SIGKILL.

The two know places where synchronous SIGKILL are generated are
do_bad_area and fpsimd_save.  The call paths to force_sig_fault are:
do_bad_area
  arm64_force_sig_fault
    force_sig_fault
force_signal_inject
  arm64_notify_die
    arm64_force_sig_fault
       force_sig_fault

Which means correcting this in arm64_force_sig_fault is enough
to ensure the arm64 code is not misusing the generic code, which
could lead to maintenance problems later.

Cc: stable@vger.kernel.org
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Fixes: af40ff687b ("arm64: signal: Ensure si_code is valid for all fault signals")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-27 09:36:27 -05:00
Will Deacon
3e29ead500 arm64: Remove useless message during oops
During an oops, we print the name of the current task and its pid twice.
We also helpfully advertise its stack limit as "0x(____ptrval____)".

Drop these useless messages.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-05-23 11:38:10 +01:00
Linus Torvalds
c620f7bd0b arm64 updates for 5.2
Mostly just incremental improvements here:
 
 - Introduce AT_HWCAP2 for advertising CPU features to userspace
 
 - Expose SVE2 availability to userspace
 
 - Support for "data cache clean to point of deep persistence" (DC PODP)
 
 - Honour "mitigations=off" on the cmdline and advertise status via sysfs
 
 - CPU timer erratum workaround (Neoverse-N1 #1188873)
 
 - Introduce perf PMU driver for the SMMUv3 performance counters
 
 - Add config option to disable the kuser helpers page for AArch32 tasks
 
 - Futex modifications to ensure liveness under contention
 
 - Rework debug exception handling to seperate kernel and user handlers
 
 - Non-critical fixes and cleanup
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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:
 "Mostly just incremental improvements here:

   - Introduce AT_HWCAP2 for advertising CPU features to userspace

   - Expose SVE2 availability to userspace

   - Support for "data cache clean to point of deep persistence" (DC PODP)

   - Honour "mitigations=off" on the cmdline and advertise status via
     sysfs

   - CPU timer erratum workaround (Neoverse-N1 #1188873)

   - Introduce perf PMU driver for the SMMUv3 performance counters

   - Add config option to disable the kuser helpers page for AArch32 tasks

   - Futex modifications to ensure liveness under contention

   - Rework debug exception handling to seperate kernel and user
     handlers

   - Non-critical fixes and cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
  Documentation: Add ARM64 to kernel-parameters.rst
  arm64/speculation: Support 'mitigations=' cmdline option
  arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB
  arm64: enable generic CPU vulnerabilites support
  arm64: add sysfs vulnerability show for speculative store bypass
  arm64: Fix size of __early_cpu_boot_status
  clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters
  clocksource/arm_arch_timer: Remove use of workaround static key
  clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable
  clocksource/arm_arch_timer: Direcly assign set_next_event workaround
  arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct
  watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvct
  ARM: vdso: Remove dependency with the arch_timer driver internals
  arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1
  arm64: Add part number for Neoverse N1
  arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT
  arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32
  arm64: mm: Remove pte_unmap_nested()
  arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable
  arm64: compat: Reduce address limit for 64K pages
  ...
2019-05-06 17:54:22 -07:00
Will Deacon
24cf262da1 Merge branch 'for-next/timers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux into for-next/core
Conflicts:
	arch/arm64/Kconfig
	arch/arm64/include/asm/arch_timer.h
2019-05-01 15:45:36 +01:00
Marc Zyngier
dea86a8003 arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct
Only arch_timer_read_counter will guarantee that workarounds are
applied. So let's use this one instead of arch_counter_get_cntvct.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30 16:10:01 +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
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
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
1e6f5440a6 arm64: backtrace: Don't bother trying to unwind the userspace stack
Calling dump_backtrace() with a pt_regs argument corresponding to
userspace doesn't make any sense and our unwinder will simply print
"Call trace:" before unwinding the stack looking for user frames.

Rather than go through this song and dance, just return early if we're
passed a user register state.

Cc: <stable@vger.kernel.org>
Fixes: 1149aad10b ("arm64: Add dump_backtrace() in show_regs")
Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-08 18:05:24 +01:00
Julien Thierry
7d31464adf arm64: Handle serror in NMI context
Per definition of the daifflags, Serrors can occur during any interrupt
context, that includes NMI contexts. Trying to nmi_enter in an nmi context
will crash.

Skip nmi_enter/nmi_exit when serror occurred during an NMI.

Suggested-by: James Morse <james.morse@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-02-06 10:05:22 +00:00
Linus Torvalds
495d714ad1 Tracing changes for v4.21:
- Rework of the kprobe/uprobe and synthetic events to consolidate all
    the dynamic event code. This will make changes in the future easier.
 
  - Partial rewrite of the function graph tracing infrastructure.
    This will allow for multiple users of hooking onto functions
    to get the callback (return) of the function. This is the ground
    work for having kprobes and function graph tracer using one code base.
 
  - Clean up of the histogram code that will facilitate adding more
    features to the histograms in the future.
 
  - Addition of str_has_prefix() and a few use cases. There currently
    is a similar function strstart() that is used in a few places, but
    only returns a bool and not a length. These instances will be
    removed in the future to use str_has_prefix() instead.
 
  - A few other various clean ups as well.
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Merge tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Rework of the kprobe/uprobe and synthetic events to consolidate all
   the dynamic event code. This will make changes in the future easier.

 - Partial rewrite of the function graph tracing infrastructure. This
   will allow for multiple users of hooking onto functions to get the
   callback (return) of the function. This is the ground work for having
   kprobes and function graph tracer using one code base.

 - Clean up of the histogram code that will facilitate adding more
   features to the histograms in the future.

 - Addition of str_has_prefix() and a few use cases. There currently is
   a similar function strstart() that is used in a few places, but only
   returns a bool and not a length. These instances will be removed in
   the future to use str_has_prefix() instead.

 - A few other various clean ups as well.

* tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
  tracing: Use the return of str_has_prefix() to remove open coded numbers
  tracing: Have the historgram use the result of str_has_prefix() for len of prefix
  tracing: Use str_has_prefix() instead of using fixed sizes
  tracing: Use str_has_prefix() helper for histogram code
  string.h: Add str_has_prefix() helper function
  tracing: Make function ‘ftrace_exports’ static
  tracing: Simplify printf'ing in seq_print_sym
  tracing: Avoid -Wformat-nonliteral warning
  tracing: Merge seq_print_sym_short() and seq_print_sym_offset()
  tracing: Add hist trigger comments for variable-related fields
  tracing: Remove hist trigger synth_var_refs
  tracing: Use hist trigger's var_ref array to destroy var_refs
  tracing: Remove open-coding of hist trigger var_ref management
  tracing: Use var_refs[] for hist trigger reference checking
  tracing: Change strlen to sizeof for hist trigger static strings
  tracing: Remove unnecessary hist trigger struct field
  tracing: Fix ftrace_graph_get_ret_stack() to use task and not current
  seq_buf: Use size_t for len in seq_buf_puts()
  seq_buf: Make seq_buf_puts() null-terminate the buffer
  arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
  ...
2018-12-31 11:46:59 -08:00
Andrey Konovalov
41eea9cd23 kasan, arm64: add brk handler for inline instrumentation
Tag-based KASAN inline instrumentation mode (which embeds checks of shadow
memory into the generated code, instead of inserting a callback) generates
a brk instruction when a tag mismatch is detected.

This commit adds a tag-based KASAN specific brk handler, that decodes the
immediate value passed to the brk instructions (to extract information
about the memory access that triggered the mismatch), reads the register
values (x0 contains the guilty address) and reports the bug.

Link: http://lkml.kernel.org/r/c91fe7684070e34dc34b419e6b69498f4dcacc2d.1544099024.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28 12:11:44 -08:00
Steven Rostedt (VMware)
a448276ce5 arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
The structure of the ret_stack array on the task struct is going to
change, and accessing it directly via the curr_ret_stack index will no
longer give the ret_stack entry that holds the return address. To access
that, architectures must now use ftrace_graph_get_ret_stack() to get the
associated ret_stack that matches the saved return address.

Cc: linux-arm-kernel@lists.infradead.org
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:21:02 -05:00
Linus Torvalds
ba9f6f8954 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull siginfo updates from Eric Biederman:
 "I have been slowly sorting out siginfo and this is the culmination of
  that work.

  The primary result is in several ways the signal infrastructure has
  been made less error prone. The code has been updated so that manually
  specifying SEND_SIG_FORCED is never necessary. The conversion to the
  new siginfo sending functions is now complete, which makes it
  difficult to send a signal without filling in the proper siginfo
  fields.

  At the tail end of the patchset comes the optimization of decreasing
  the size of struct siginfo in the kernel from 128 bytes to about 48
  bytes on 64bit. The fundamental observation that enables this is by
  definition none of the known ways to use struct siginfo uses the extra
  bytes.

  This comes at the cost of a small user space observable difference.
  For the rare case of siginfo being injected into the kernel only what
  can be copied into kernel_siginfo is delivered to the destination, the
  rest of the bytes are set to 0. For cases where the signal and the
  si_code are known this is safe, because we know those bytes are not
  used. For cases where the signal and si_code combination is unknown
  the bits that won't fit into struct kernel_siginfo are tested to
  verify they are zero, and the send fails if they are not.

  I made an extensive search through userspace code and I could not find
  anything that would break because of the above change. If it turns out
  I did break something it will take just the revert of a single change
  to restore kernel_siginfo to the same size as userspace siginfo.

  Testing did reveal dependencies on preferring the signo passed to
  sigqueueinfo over si->signo, so bit the bullet and added the
  complexity necessary to handle that case.

  Testing also revealed bad things can happen if a negative signal
  number is passed into the system calls. Something no sane application
  will do but something a malicious program or a fuzzer might do. So I
  have fixed the code that performs the bounds checks to ensure negative
  signal numbers are handled"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
  signal: Guard against negative signal numbers in copy_siginfo_from_user32
  signal: Guard against negative signal numbers in copy_siginfo_from_user
  signal: In sigqueueinfo prefer sig not si_signo
  signal: Use a smaller struct siginfo in the kernel
  signal: Distinguish between kernel_siginfo and siginfo
  signal: Introduce copy_siginfo_from_user and use it's return value
  signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
  signal: Fail sigqueueinfo if si_signo != sig
  signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
  signal/unicore32: Use force_sig_fault where appropriate
  signal/unicore32: Generate siginfo in ucs32_notify_die
  signal/unicore32: Use send_sig_fault where appropriate
  signal/arc: Use force_sig_fault where appropriate
  signal/arc: Push siginfo generation into unhandled_exception
  signal/ia64: Use force_sig_fault where appropriate
  signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
  signal/ia64: Use the generic force_sigsegv in setup_frame
  signal/arm/kvm: Use send_sig_mceerr
  signal/arm: Use send_sig_fault where appropriate
  signal/arm: Use force_sig_fault where appropriate
  ...
2018-10-24 11:22:39 +01:00
Marc Zyngier
c219bc4e92 arm64: Trap WFI executed in userspace
It recently came to light that userspace can execute WFI, and that
the arm64 kernel doesn't trap this event. This sounds rather benign,
but the kernel should decide when it wants to wait for an interrupt,
and not userspace.

Let's trap WFI and immediately return after having skipped the
instruction. This effectively makes WFI a rather expensive NOP.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 16:52:24 +01:00
Marc Zyngier
32a3e635fb arm64: compat: Add CNTFRQ trap handler
Just like CNTVCT, we need to handle userspace trapping into the
kernel if we're decided that the timer wasn't fit for purpose...
64bit userspace is already dealt with, but we're missing the
equivalent compat handling.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:36:03 +01:00
Marc Zyngier
50de013d22 arm64: compat: Add CNTVCT trap handler
Since people seem to make a point in breaking the userspace visible
counter, we have no choice but to trap the access. We already do this
for 64bit userspace, but this is lacking for compat. Let's provide
the required handler.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:36:01 +01:00
Marc Zyngier
2a8905e18c arm64: compat: Add cp15_32 and cp15_64 handler arrays
We're now ready to start handling CP15 access. Let's add (empty)
arrays for both 32 and 64bit accessors, and the code that deals
with them.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:35:59 +01:00
Marc Zyngier
1f1c014035 arm64: compat: Add condition code checks and IT advance
Here's a /really nice/ part of the architecture: a CP15 access is
allowed to trap even if it fails its condition check, and SW must
handle it. This includes decoding the IT state if this happens in
am IT block. As a consequence, SW must also deal with advancing
the IT state machine.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:35:56 +01:00
Marc Zyngier
70c63cdfd6 arm64: compat: Add separate CP15 trapping hook
Instead of directly generating an UNDEF when trapping a CP15 access,
let's add a new entry point to that effect (which only generates an
UNDEF for now).

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-01 13:35:53 +01:00
Eric W. Biederman
f3a900b341 signal/arm64: Add and use arm64_force_sig_ptrace_errno_trap
Add arm64_force_sig_ptrace_errno_trap for consistency with
arm64_force_sig_fault and use it where appropriate.

This adds the show_signal logic to the force_sig_errno_trap case,
where it was apparently overlooked earlier.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:55:15 +02:00
Eric W. Biederman
009f608ab2 signal/arm64: Remove arm64_force_sig_info
The function has no more callers so remove it.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:55:00 +02:00
Eric W. Biederman
b4d5557caa signal/arm64: Add and use arm64_force_sig_mceerr as appropriate
Add arm64_force_sig_mceerr for consistency with arm64_force_sig_fault,
and use it in the one location that can take advantage of it.

This removes the fiddly filling out of siginfo before sending a signal
reporting an memory error to userspace.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:54:51 +02:00
Eric W. Biederman
feca355b3d signal/arm64: Add and use arm64_force_sig_fault where appropriate
Wrap force_sig_fault with a helper that calls arm64_show_signal
and call arm64_force_sig_fault where appropraite.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2018-09-27 21:54:43 +02:00
Eric W. Biederman
1628a7cc85 signal/arm64: Factor out arm64_show_signal from arm64_force_sig_info
Filling in siginfo is error prone and so it is wise to use more
specialized helpers to do that work.  Factor out the arm specific
unhandled signal reporting from the work of delivering a signal so
the code can be modified to use functions that take the information
to fill out siginfo as parameters.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-27 21:53:46 +02:00