Commit Graph

2630 Commits

Author SHA1 Message Date
Linus Torvalds
a2303849a6 Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The biggest change in this cycle were SGI/UV related changes that
  clean up and fix UV boot quirks and problems.

  There's also various smaller cleanups and refinements"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: Reorganize the GUID table to make it easier to read
  x86/efi: Remove the unused efi_get_time() function
  x86/efi: Update efi_thunk() to use the the arch_efi_call_virt*() macros
  x86/uv: Update uv_bios_call() to use efi_call_virt_pointer()
  efi: Convert efi_call_virt() to efi_call_virt_pointer()
  x86/efi: Remove unused variable 'efi'
  efi: Document #define FOO_PROTOCOL_GUID layout
  efibc: Report more information in the error messages
2016-07-25 12:30:01 -07:00
Rafael J. Wysocki
d5f017b796 Merge branch 'acpi-tables'
* acpi-tables:
  ACPI: Rename configfs.c to acpi_configfs.c to prevent link error
  ACPI: add support for loading SSDTs via configfs
  ACPI: add support for configfs
  efi / ACPI: load SSTDs from EFI variables
  spi / ACPI: add support for ACPI reconfigure notifications
  i2c / ACPI: add support for ACPI reconfigure notifications
  ACPI: add support for ACPI reconfiguration notifiers
  ACPI / scan: fix enumeration (visited) flags for bus rescans
  ACPI / documentation: add SSDT overlays documentation
  ACPI: ARM64: support for ACPI_TABLE_UPGRADE
  ACPI / tables: introduce ARCH_HAS_ACPI_TABLE_UPGRADE
  ACPI / tables: move arch-specific symbol to asm/acpi.h
  ACPI / tables: table upgrade: refactor function definitions
  ACPI / tables: table upgrade: use cacheable map for tables

Conflicts:
	arch/arm64/include/asm/acpi.h
2016-07-25 13:41:01 +02:00
Rafael J. Wysocki
d85f4eb699 Merge branch 'acpi-numa'
* acpi-numa:
  ACPI / NUMA: Enable ACPI based NUMA on ARM64
  arm64, ACPI, NUMA: NUMA support based on SRAT and SLIT
  ACPI / processor: Add acpi_map_madt_entry()
  ACPI / NUMA: Improve SRAT error detection and add messages
  ACPI / NUMA: Move acpi_numa_memory_affinity_init() to drivers/acpi/numa.c
  ACPI / NUMA: remove unneeded acpi_numa=1
  ACPI / NUMA: move bad_srat() and srat_disabled() to drivers/acpi/numa.c
  x86 / ACPI / NUMA: cleanup acpi_numa_processor_affinity_init()
  arm64, NUMA: Cleanup NUMA disabled messages
  arm64, NUMA: rework numa_add_memblk()
  ACPI / NUMA: move acpi_numa_slit_init() to drivers/acpi/numa.c
  ACPI / NUMA: Move acpi_numa_arch_fixup() to ia64 only
  ACPI / NUMA: remove duplicate NULL check
  ACPI / NUMA: Replace ACPI_DEBUG_PRINT() with pr_debug()
  ACPI / NUMA: Use pr_fmt() instead of printk
2016-07-25 13:40:39 +02:00
Catalin Marinas
a95b0644b3 Merge branch 'for-next/kprobes' into for-next/core
* kprobes:
  arm64: kprobes: Add KASAN instrumentation around stack accesses
  arm64: kprobes: Cleanup jprobe_return
  arm64: kprobes: Fix overflow when saving stack
  arm64: kprobes: WARN if attempting to step with PSTATE.D=1
  kprobes: Add arm64 case in kprobe example module
  arm64: Add kernel return probes support (kretprobes)
  arm64: Add trampoline code for kretprobes
  arm64: kprobes instruction simulation support
  arm64: Treat all entry code as non-kprobe-able
  arm64: Blacklist non-kprobe-able symbol
  arm64: Kprobes with single stepping support
  arm64: add conditional instruction simulation support
  arm64: Add more test functions to insn.c
  arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature
2016-07-21 18:20:41 +01:00
Will Deacon
2572214170 arm64: debug: remove unused local_dbg_{enable, disable} macros
The debug enable/disable macros are not used anywhere in the kernel, so
remove them from irqflags.h

Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 16:59:40 +01:00
Vladimir Murzin
9df53ff2bb arm64: ptrace: remove extra define for CPSR's E bit
...and do not confuse source navigation tools ;)

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:27:43 +01:00
William Cohen
da6a91252a arm64: Add trampoline code for kretprobes
The trampoline code is used by kretprobes to capture a return from a probed
function.  This is done by saving the registers, calling the handler, and
restoring the registers. The code then returns to the original saved caller
return address. It is necessary to do this directly instead of using a
software breakpoint because the code used in processing that breakpoint
could itself be kprobe'd and cause a problematic reentry into the debug
exception handler.

Signed-off-by: William Cohen <wcohen@redhat.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: removed unnecessary masking of the PSTATE bits]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:03:22 +01:00
Sandeepa Prabhu
39a67d49ba arm64: kprobes instruction simulation support
Kprobes needs simulation of instructions that cannot be stepped
from a different memory location, e.g.: those instructions
that uses PC-relative addressing. In simulation, the behaviour
of the instruction is implemented using a copy of pt_regs.

The following instruction categories are simulated:
 - All branching instructions(conditional, register, and immediate)
 - Literal access instructions(load-literal, adr/adrp)

Conditional execution is limited to branching instructions in
ARM v8. If conditions at PSTATE do not match the condition fields
of opcode, the instruction is effectively NOP.

Thanks to Will Cohen for assorted suggested changes.

Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: William Cohen <wcohen@redhat.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: removed linux/module.h include]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:03:21 +01:00
Sandeepa Prabhu
2dd0e8d2d2 arm64: Kprobes with single stepping support
Add support for basic kernel probes(kprobes) and jump probes
(jprobes) for ARM64.

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

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

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

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

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

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

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

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

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

Thanks to Steve Capper and Pratyush Anand for several suggested
Changes.

Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Signed-off-by: Pratyush Anand <panand@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:03:20 +01:00
David A. Long
2af3ec08b4 arm64: add conditional instruction simulation support
Cease using the arm32 arm_check_condition() function and replace it with
a local version for use in deprecated instruction support on arm64. Also
make the function table used by this available for future use by kprobes
and/or uprobes.

This function is derived from code written by Sandeepa Prabhu.

Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:03:19 +01:00
David A. Long
d59bee8872 arm64: Add more test functions to insn.c
Certain instructions are hard to execute correctly out-of-line (as in
kprobes).  Test functions are added to insn.[hc] to identify these.  The
instructions include any that use PC-relative addressing, change the PC,
or change interrupt masking. For efficiency and simplicity test
functions are also added for small collections of related instructions.

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:03:19 +01:00
David A. Long
0a8ea52c3e arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature
Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64, including supporting
functions and defines.

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
[catalin.marinas@arm.com: Remove unused functions]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 15:03:18 +01:00
Andre Przywara
b46f01ce4d KVM: arm/arm64: Extend arch CAP checks to allow per-VM capabilities
KVM capabilities can be a per-VM property, though ARM/ARM64 currently
does not pass on the VM pointer to the architecture specific
capability handlers.
Add a "struct kvm*" parameter to those function to later allow proper
per-VM capability reporting.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-07-18 18:10:31 +01:00
Steve Capper
f8d9f92452 arm64: cpuinfo: Expose MIDR_EL1 and REVIDR_EL1 to sysfs
It can be useful for JIT software to be aware of MIDR_EL1 and
REVIDR_EL1 to ascertain the presence of any core errata that could
affect code generation.

This patch exposes these registers through sysfs:

/sys/devices/system/cpu/cpu$ID/regs/identification/midr_el1
/sys/devices/system/cpu/cpu$ID/regs/identification/revidr_el1

where $ID is the cpu number. For big.LITTLE systems, one can have a
mixture of cores (e.g. Cortex A53 and Cortex A57), thus all CPUs need
to be enumerated.

If the kernel does not have valid information to populate these entries
with, an empty string is returned to userspace.

Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
[suzuki.poulose@arm.com: ABI documentation updates, hotplug notifiers, kobject changes]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-12 16:09:37 +01:00
Kevin Brodsky
49eea433b3 arm64: Add support for CLOCK_MONOTONIC_RAW in clock_gettime() vDSO
So far the arm64 clock_gettime() vDSO implementation only supported
the following clocks, falling back to the syscall for the others:
- CLOCK_REALTIME{,_COARSE}
- CLOCK_MONOTONIC{,_COARSE}

This patch adds support for the CLOCK_MONOTONIC_RAW clock, taking
advantage of the recent refactoring of the vDSO time functions. Like
the non-_COARSE clocks, this only works when the "arch_sys_counter"
clocksource is in use (allowing us to read the current time from the
virtual counter register), otherwise we also have to fall back to the
syscall.

Most of the data is shared with CLOCK_MONOTONIC, and the algorithm is
similar. The reference implementation in kernel/time/timekeeping.c
shows that:
- CLOCK_MONOTONIC = tk->wall_to_monotonic + tk->xtime_sec +
  timekeeping_get_ns(&tk->tkr_mono)
- CLOCK_MONOTONIC_RAW = tk->raw_time + timekeeping_get_ns(&tk->tkr_raw)
- tkr_mono and tkr_raw are identical (in particular, same
  clocksource), except these members:
  * mult (only mono's multiplier is NTP-adjusted)
  * xtime_nsec (always 0 for raw)

Therefore, tk->raw_time and tkr_raw->mult are now also stored in the
vDSO data page.

Cc: Ali Saidi <ali.saidi@arm.com>
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-12 16:06:32 +01:00
Ganapatrao Kulkarni
47c459beab arm64: Enable workaround for Cavium erratum 27456 on thunderx-81xx
Cavium erratum 27456 commit 104a0c02e8
("arm64: Add workaround for Cavium erratum 27456")
is applicable for thunderx-81xx pass1.0 SoC as well.
Adding code to enable to 81xx.

Signed-off-by: Ganapatrao Kulkarni <gkulkarni@cavium.com>
Reviewed-by: Andrew Pinski <apinski@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-07 18:35:21 +01:00
James Morse
e19a6ee246 arm64: kernel: Save and restore UAO and addr_limit on exception entry
If we take an exception while at EL1, the exception handler inherits
the original context's addr_limit and PSTATE.UAO values. To be consistent
always reset addr_limit and PSTATE.UAO on (re-)entry to EL1. This
prevents accidental re-use of the original context's addr_limit.

Based on a similar patch for arm from Russell King.

Cc: <stable@vger.kernel.org> # 4.6-
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-07 15:55:37 +01:00
Ingo Molnar
36e91aa262 Merge branch 'locking/arch-atomic' into locking/core, because the topic is ready
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 09:12:02 +02:00
Will Deacon
03e3c2b7ed locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
smp_cond_load_acquire() is used to spin on a variable until some
expression involving that variable becomes true.

On arm64, we can build this using the LDXR and WFE instructions, since
clearing of the exclusive monitor as a result of the variable being
changed by another CPU generates an event, which will wake us up out of WFE.

This patch implements smp_cond_load_acquire() using LDXR and WFE, which
themselves are contained in an internal __cmpwait() function.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: catalin.marinas@arm.com
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1467049434-30451-1-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07 09:10:53 +02:00
Shannon Zhao
be1aaf4e40 ARM64: XEN: Add a function to initialize Xen specific UEFI runtime services
When running on Xen hypervisor, runtime services are supported through
hypercall. Add a Xen specific function to initialize runtime services.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-06 10:34:46 +01:00
Marc Zyngier
6c41a413fd arm/arm64: Get rid of KERN_TO_HYP
We have both KERN_TO_HYP and kern_hyp_va, which do the exact same
thing. Let's standardize on the latter.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
f7bec68d2f arm/arm64: KVM: Prune unused #defines
We can now remove a number of dead #defines, thanks to the trampoline
code being gone.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
e537ecd7ef arm: KVM: Allow hyp teardown
So far, KVM was getting in the way of kexec on 32bit (and the arm64
kexec hackers couldn't be bothered to fix it on 32bit...).

With simpler page tables, tearing KVM down becomes very easy, so
let's just do it.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
26781f9ce1 arm/arm64: KVM: Kill free_boot_hyp_pgd
There is no way to free the boot PGD, because it doesn't exist
anymore as a standalone entity.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
12fda8123d arm/arm64: KVM: Drop boot_pgd
Since we now only have one set of page tables, the concept of
boot_pgd is useless and can be removed. We still keep it as
an element of the "extended idmap" thing.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
3421e9d88d arm64: KVM: Simplify HYP init/teardown
Now that we only have the "merged page tables" case to deal with,
there is a bunch of things we can simplify in the HYP code (both
at init and teardown time).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
1df3e2347a arm/arm64: KVM: Export __hyp_text_start/end symbols
Declare the __hyp_text_start/end symbols in asm/virt.h so that
they can be reused without having to declare them locally.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
fd81e6bf39 arm64: KVM: Refactor kern_hyp_va to deal with multiple offsets
As we move towards a selectable HYP VA range, it is obvious that
we don't want to test a variable to find out if we need to use
the bottom VA range, the top VA range, or use the address as is
(for VHE).

Instead, we can expand our current helper to generate the right
mask or nop with code patching. We default to using the top VA
space, with alternatives to switch to the bottom one or to nop
out the instructions.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
d53d9bc652 arm64: KVM: Define HYP offset masks
Define the two possible HYP VA regions in terms of VA_BITS,
and keep HYP_PAGE_OFFSET_MASK as a temporary compatibility
definition.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
853c3b21ff arm64: Add ARM64_HYP_OFFSET_LOW capability
As we need to indicate to the rest of the kernel which region of
the HYP VA space is safe to use, add a capability that will
indicate that KVM should use the [VA_BITS-2:0] range.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
fd16fe6820 arm64: KVM: Kill HYP_PAGE_OFFSET
HYP_PAGE_OFFSET is not massively useful. And the way we use it
in KERN_HYP_VA is inconsistent with the equivalent operation in
EL2, where we use a mask instead.

Let's replace the uses of HYP_PAGE_OFFSET with HYP_PAGE_OFFSET_MASK,
and get rid of the pointless macro.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
3f0f8830d4 arm/arm64: KVM: Remove hyp_kern_va helper
hyp_kern_va is now completely unused, so let's remove it entirely.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Marc Zyngier
82a81bff90 arm64: KVM: Merged page tables documentation
Since dealing with VA ranges tends to hurt my brain badly, let's
start with a bit of documentation that will hopefully help
understanding what comes next...

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03 23:41:27 +02:00
Ard Biesheuvel
bd264d046a arm64: efi: always map runtime services code and data regions down to pages
To avoid triggering diagnostics in the MMU code that are finicky about
splitting block mappings into more granular mappings, ensure that regions
that are likely to appear in the Memory Attributes table as well as the
UEFI memory map are always mapped down to pages. This way, we can use
apply_to_page_range() instead of create_pgd_mapping() for the second pass,
which cannot split or merge block entries, and operates strictly on PTEs.

Note that this aligns the arm64 Memory Attributes table handling code with
the ARM code, which already uses apply_to_page_range() to set the strict
permissions.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:56:26 +01:00
Ard Biesheuvel
53e1b32910 arm64: mm: add param to force create_pgd_mapping() to use page mappings
Add a bool parameter 'allow_block_mappings' to create_pgd_mapping() and
the various helper functions that it descends into, to give the caller
control over whether block entries may be used to create the mapping.

The UEFI runtime mapping routines will use this to avoid creating block
entries that would need to split up into page entries when applying the
permissions listed in the Memory Attributes firmware table.

This also replaces the block_mappings_allowed() helper function that was
added for DEBUG_PAGEALLOC functionality, but the resulting code is
functionally equivalent (given that debug_page_alloc does not operate on
EFI page table entries anyway)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:56:26 +01:00
Andre Przywara
7dd01aef05 arm64: trap userspace "dc cvau" cache operation on errata-affected core
The ARM errata 819472, 826319, 827319 and 824069 for affected
Cortex-A53 cores demand to promote "dc cvau" instructions to
"dc civac". Since we allow userspace to also emit those instructions,
we should make sure that "dc cvau" gets promoted there too.
So lets grasp the nettle here and actually trap every userland cache
maintenance instruction once we detect at least one affected core in
the system.
We then emulate the instruction by executing it on behalf of userland,
promoting "dc cvau" to "dc civac" on the way and injecting access
fault back into userspace.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
[catalin.marinas@arm.com: s/set_segfault/arm64_notify_segfault/]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:46:00 +01:00
Andre Przywara
390bf1773c arm64: consolidate signal injection on emulation errors
The code for injecting a signal into userland if a trapped instruction
fails emulation due to a _userland_ error (like an illegal address)
will be used more often with the next patch.
Factor out the core functionality into a separate function and use
that both for the existing trap handler and for the deprecated
instructions emulation.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
[catalin.marinas@arm.com: s/set_segfault/arm64_notify_segfault/]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:43:30 +01:00
Andre Przywara
8e2318521b arm64: errata: Calling enable functions for CPU errata too
Currently we call the (optional) enable function for CPU _features_
only. As CPU _errata_ descriptions share the same data structure and
having an enable function is useful for errata as well (for instance
to set bits in SCTLR), lets call it when enumerating erratas too.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:30:28 +01:00
Andre Przywara
823066d9ed arm64: include alternative handling in dcache_by_line_op
The newly introduced dcache_by_line_op macro is used at least in
one occassion at the moment to issue a "dc cvau" instruction,
which is affected by ARM errata 819472, 826319, 827319 and 824069.
Change the macro to allow for alternative patching in there to
protect affected Cortex-A53 cores.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
[catalin.marinas@arm.com: indentation fixups]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:28:16 +01:00
Andre Przywara
290622efc7 arm64: fix "dc cvau" cache operation on errata-affected core
The ARM errata 819472, 826319, 827319 and 824069 for affected
Cortex-A53 cores demand to promote "dc cvau" instructions to
"dc civac" as well.
Attribute the usage of the instruction in __flush_cache_user_range
to also be covered by our alternative patching efforts.
For that we introduce an assembly macro which both deals with
alternatives while still tagging the instructions as USER.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:26:20 +01:00
Andre Przywara
b82bfa4793 Revert "arm64: alternatives: add enable parameter to conditional asm macros"
Commit 77ee306c0a ("arm64: alternatives: add enable parameter to
conditional asm macros") extended the alternative assembly macros.
Unfortunately this does not really work as one would expect, as the
enable parameter in fact correctly protects the alternative section
magic, but not the actual code sequences.
This results in having both the original instruction(s) _and_  the
alternative ones, if enable if false.
Since there is no user of this macros anyway, just revert it.

This reverts commit 77ee306c0a.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-01 11:26:15 +01:00
Marc Zyngier
0996353f8e arm/arm64: KVM: Make default HYP mappings non-excutable
Structures that can be generally written to don't have any requirement
to be executable (quite the opposite). This includes the kvm and vcpu
structures, as well as the stacks.

Let's change the default to incorporate the XN flag.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-29 14:01:34 +02:00
Marc Zyngier
5900270550 arm/arm64: KVM: Map the HYP text as read-only
There should be no reason for mapping the HYP text read/write.

As such, let's have a new set of flags (PAGE_HYP_EXEC) that allows
execution, but makes the page as read-only, and update the two call
sites that deal with mapping code.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-29 14:01:34 +02:00
Marc Zyngier
74a6b8885f arm/arm64: KVM: Enforce HYP read-only mapping of the kernel's rodata section
In order to be able to use C code in HYP, we're now mapping the kernel's
rodata in HYP. It works absolutely fine, except that we're mapping it RWX,
which is not what it should be.

Add a new HYP_PAGE_RO protection, and pass it as the protection flags
when mapping the rodata section.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-29 13:59:14 +02:00
Marc Zyngier
1166f3fe6a arm64: Add PTE_HYP_XN page table flag
EL2 page tables can be configured to deny code from being
executed, which is done by setting bit 54 in the page descriptor.

It is the same bit as PTE_UXN, but the "USER" reference felt odd
in the hypervisor code.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-29 13:59:14 +02:00
Marc Zyngier
c8dddecdeb arm/arm64: KVM: Add a protection parameter to create_hyp_mappings
Currently, create_hyp_mappings applies a "one size fits all" page
protection (PAGE_HYP). As we're heading towards separate protections
for different sections, let's make this protection a parameter, and
let the callers pass their prefered protection (PAGE_HYP for everyone
for the time being).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-29 13:59:14 +02:00
Geoff Levand
d28f6df130 arm64/kexec: Add core kexec support
Add three new files, kexec.h, machine_kexec.c and relocate_kernel.S to the
arm64 architecture that add support for the kexec re-boot mechanism
(CONFIG_KEXEC) on arm64 platforms.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Reviewed-by: James Morse <james.morse@arm.com>
[catalin.marinas@arm.com: removed dead code following James Morse's comments]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-27 16:31:25 +01:00
Geoff Levand
f9076ecfb1 arm64: Add back cpu reset routines
Commit 68234df4ea ("arm64: kill flush_cache_all()") removed the global
arm64 routines cpu_reset() and cpu_soft_restart() needed by the arm64
kexec and kdump support.  Add back a simplified version of
cpu_soft_restart() with some changes needed for kexec in the new files
cpu_reset.S, and cpu_reset.h.

When a CPU is reset it needs to be put into the exception level it had when
it entered the kernel. Update cpu_soft_restart() to accept an argument
which signals if the reset address should be entered at EL1 or EL2, and
add a new hypercall HVC_SOFT_RESTART which is used for the EL2 switch.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-27 16:31:25 +01:00
James Morse
b69e0dc14c arm64: smp: Add function to determine if cpus are stuck in the kernel
kernel/smp.c has a fancy counter that keeps track of the number of CPUs
it marked as not-present and left in cpu_park_loop(). If there are any
CPUs spinning in here, features like kexec or hibernate may release them
by overwriting this memory.

This problem also occurs on machines using spin-tables to release
secondary cores.
After commit 44dbcc93ab ("arm64: Fix behavior of maxcpus=N")
we bring all known cpus into the secondary holding pen, meaning this
memory can't be re-used by kexec or hibernate.

Add a function cpus_are_stuck_in_kernel() to determine if either of these
cases have occurred.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: cherry-picked from mainline for kexec dependency]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-27 16:24:51 +01:00
Alex Thorlton
80e7559607 efi: Convert efi_call_virt() to efi_call_virt_pointer()
This commit makes a few slight modifications to the efi_call_virt() macro
to get it to work with function pointers that are stored in locations
other than efi.systab->runtime, and renames the macro to
efi_call_virt_pointer().  The majority of the changes here are to pull
these macros up into header files so that they can be accessed from
outside of drivers/firmware/efi/runtime-wrappers.c.

The most significant change not directly related to the code move is to
add an extra "p" argument into the appropriate efi_call macros, and use
that new argument in place of the, formerly hard-coded,
efi.systab->runtime pointer.

The last piece of the puzzle was to add an efi_call_virt() macro back into
drivers/firmware/efi/runtime-wrappers.c to wrap around the new
efi_call_virt_pointer() macro - this was mainly to keep the code from
looking too cluttered by adding a bunch of extra references to
efi.systab->runtime everywhere.

Note that I also broke up the code in the efi_call_virt_pointer() macro a
bit in the process of moving it.

Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roy Franz <roy.franz@linaro.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1466839230-12781-5-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-27 13:06:56 +02:00