1. 28 Apr, 2016 1 commit
    • James Morse's avatar
      arm64: kernel: Add support for hibernate/suspend-to-disk · 82869ac5
      James Morse authored
      Add support for hibernate/suspend-to-disk.
      
      Suspend borrows code from cpu_suspend() to write cpu state onto the stack,
      before calling swsusp_save() to save the memory image.
      
      Restore creates a set of temporary page tables, covering only the
      linear map, copies the restore code to a 'safe' page, then uses the copy to
      restore the memory image. The copied code executes in the lower half of the
      address space, and once complete, restores the original kernel's page
      tables. It then calls into cpu_resume(), and follows the normal
      cpu_suspend() path back into the suspend code.
      
      To restore a kernel using KASLR, the address of the page tables, and
      cpu_resume() are stored in the hibernate arch-header and the el2
      vectors are pivotted via the 'safe' page in low memory.
      Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Tested-by: Kevin Hilman <khilman@baylibre.com> # Tested on Juno R2
      Signed-off-by: default avatarJames Morse <james.morse@arm.com>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      82869ac5
  2. 24 Feb, 2016 2 commits
    • Ard Biesheuvel's avatar
      arm64: add support for kernel ASLR · f80fb3a3
      Ard Biesheuvel authored
      This adds support for KASLR is implemented, based on entropy provided by
      the bootloader in the /chosen/kaslr-seed DT property. Depending on the size
      of the address space (VA_BITS) and the page size, the entropy in the
      virtual displacement is up to 13 bits (16k/2 levels) and up to 25 bits (all
      4 levels), with the sidenote that displacements that result in the kernel
      image straddling a 1GB/32MB/512MB alignment boundary (for 4KB/16KB/64KB
      granule kernels, respectively) are not allowed, and will be rounded up to
      an acceptable value.
      
      If CONFIG_RANDOMIZE_MODULE_REGION_FULL is enabled, the module region is
      randomized independently from the core kernel. This makes it less likely
      that the location of core kernel data structures can be determined by an
      adversary, but causes all function calls from modules into the core kernel
      to be resolved via entries in the module PLTs.
      
      If CONFIG_RANDOMIZE_MODULE_REGION_FULL is not enabled, the module region is
      randomized by choosing a page aligned 128 MB region inside the interval
      [_etext - 128 MB, _stext + 128 MB). This gives between 10 and 14 bits of
      entropy (depending on page size), independently of the kernel randomization,
      but still guarantees that modules are within the range of relative branch
      and jump instructions (with the caveat that, since the module region is
      shared with other uses of the vmalloc area, modules may need to be loaded
      further away if the module region is exhausted)
      Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      f80fb3a3
    • Ard Biesheuvel's avatar
      arm64: add support for module PLTs · fd045f6c
      Ard Biesheuvel authored
      This adds support for emitting PLTs at module load time for relative
      branches that are out of range. This is a prerequisite for KASLR, which
      may place the kernel and the modules anywhere in the vmalloc area,
      making it more likely that branch target offsets exceed the maximum
      range of +/- 128 MB.
      
      In this version, I removed the distinction between relocations against
      .init executable sections and ordinary executable sections. The reason
      is that it is hardly worth the trouble, given that .init.text usually
      does not contain that many far branches, and this version now only
      reserves PLT entry space for jump and call relocations against undefined
      symbols (since symbols defined in the same module can be assumed to be
      within +/- 128 MB)
      
      For example, the mac80211.ko module (which is fairly sizable at ~400 KB)
      built with -mcmodel=large gives the following relocation counts:
      
                          relocs    branches   unique     !local
        .text              3925       3347       518        219
        .init.text           11          8         7          1
        .exit.text            4          4         4          1
        .text.unlikely       81         67        36         17
      
      ('unique' means branches to unique type/symbol/addend combos, of which
      !local is the subset referring to undefined symbols)
      
      IOW, we are only emitting a single PLT entry for the .init sections, and
      we are better off just adding it to the core PLT section instead.
      Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      fd045f6c
  3. 16 Feb, 2016 1 commit
    • Lorenzo Pieralisi's avatar
      arm64: kernel: implement ACPI parking protocol · 5e89c55e
      Lorenzo Pieralisi authored
      The SBBR and ACPI specifications allow ACPI based systems that do not
      implement PSCI (eg systems with no EL3) to boot through the ACPI parking
      protocol specification[1].
      
      This patch implements the ACPI parking protocol CPU operations, and adds
      code that eases parsing the parking protocol data structures to the
      ARM64 SMP initializion carried out at the same time as cpus enumeration.
      
      To wake-up the CPUs from the parked state, this patch implements a
      wakeup IPI for ARM64 (ie arch_send_wakeup_ipi_mask()) that mirrors the
      ARM one, so that a specific IPI is sent for wake-up purpose in order
      to distinguish it from other IPI sources.
      
      Given the current ACPI MADT parsing API, the patch implements a glue
      layer that helps passing MADT GICC data structure from SMP initialization
      code to the parking protocol implementation somewhat overriding the CPU
      operations interfaces. This to avoid creating a completely trasparent
      DT/ACPI CPU operations layer that would require creating opaque
      structure handling for CPUs data (DT represents CPU through DT nodes, ACPI
      through static MADT table entries), which seems overkill given that ACPI
      on ARM64 mandates only two booting protocols (PSCI and parking protocol),
      so there is no need for further protocol additions.
      
      Based on the original work by Mark Salter <msalter@redhat.com>
      
      [1] https://acpica.org/sites/acpica/files/MP%20Startup%20for%20ARM%20platforms.docxSigned-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
      Tested-by: default avatarLoc Ho <lho@apm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Hanjun Guo <hanjun.guo@linaro.org>
      Cc: Sudeep Holla <sudeep.holla@arm.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Al Stone <ahs3@redhat.com>
      [catalin.marinas@arm.com: Added WARN_ONCE(!acpi_parking_protocol_valid() on the IPI]
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      5e89c55e
  4. 04 Jan, 2016 2 commits
  5. 21 Dec, 2015 1 commit
  6. 30 Oct, 2015 1 commit
  7. 12 Oct, 2015 2 commits
    • Andrey Ryabinin's avatar
      arm64: add KASAN support · 39d114dd
      Andrey Ryabinin authored
      This patch adds arch specific code for kernel address sanitizer
      (see Documentation/kasan.txt).
      
      1/8 of kernel addresses reserved for shadow memory. There was no
      big enough hole for this, so virtual addresses for shadow were
      stolen from vmalloc area.
      
      At early boot stage the whole shadow region populated with just
      one physical page (kasan_zero_page). Later, this page reused
      as readonly zero shadow for some memory that KASan currently
      don't track (vmalloc).
      After mapping the physical memory, pages for shadow memory are
      allocated and mapped.
      
      Functions like memset/memmove/memcpy do a lot of memory accesses.
      If bad pointer passed to one of these function it is important
      to catch this. Compiler's instrumentation cannot do this since
      these functions are written in assembly.
      KASan replaces memory functions with manually instrumented variants.
      Original functions declared as weak symbols so strong definitions
      in mm/kasan/kasan.c could replace them. Original functions have aliases
      with '__' prefix in name, so we could call non-instrumented variant
      if needed.
      Some files built without kasan instrumentation (e.g. mm/slub.c).
      Original mem* function replaced (via #define) with prefixed variants
      to disable memory access checks for such files.
      Signed-off-by: default avatarAndrey Ryabinin <ryabinin.a.a@gmail.com>
      Tested-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      39d114dd
    • Ard Biesheuvel's avatar
      arm64/efi: isolate EFI stub from the kernel proper · e8f3010f
      Ard Biesheuvel authored
      Since arm64 does not use a builtin decompressor, the EFI stub is built
      into the kernel proper. So far, this has been working fine, but actually,
      since the stub is in fact a PE/COFF relocatable binary that is executed
      at an unknown offset in the 1:1 mapping provided by the UEFI firmware, we
      should not be seamlessly sharing code with the kernel proper, which is a
      position dependent executable linked at a high virtual offset.
      
      So instead, separate the contents of libstub and its dependencies, by
      putting them into their own namespace by prefixing all of its symbols
      with __efistub. This way, we have tight control over what parts of the
      kernel proper are referenced by the stub.
      Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Reviewed-by: default avatarMatt Fleming <matt.fleming@intel.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      e8f3010f
  8. 24 Aug, 2015 1 commit
  9. 29 Jul, 2015 1 commit
  10. 27 Jul, 2015 2 commits
  11. 30 Mar, 2015 1 commit
  12. 25 Mar, 2015 1 commit
  13. 19 Mar, 2015 1 commit
  14. 26 Feb, 2015 1 commit
    • Will Deacon's avatar
      arm64: psci: move psci firmware calls out of line · f5e0a12c
      Will Deacon authored
      An arm64 allmodconfig fails to build with GCC 5 due to __asmeq
      assertions in the PSCI firmware calling code firing due to mcount
      preambles breaking our assumptions about register allocation of function
      arguments:
      
        /tmp/ccDqJsJ6.s: Assembler messages:
        /tmp/ccDqJsJ6.s:60: Error: .err encountered
        /tmp/ccDqJsJ6.s:61: Error: .err encountered
        /tmp/ccDqJsJ6.s:62: Error: .err encountered
        /tmp/ccDqJsJ6.s:99: Error: .err encountered
        /tmp/ccDqJsJ6.s:100: Error: .err encountered
        /tmp/ccDqJsJ6.s:101: Error: .err encountered
      
      This patch fixes the issue by moving the PSCI calls out-of-line into
      their own assembly files, which are safe from the compiler's meddling
      fingers.
      Reported-by: default avatarAndy Whitcroft <apw@canonical.com>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      f5e0a12c
  15. 27 Jan, 2015 2 commits
    • Lorenzo Pieralisi's avatar
      arm64: kernel: remove ARM64_CPU_SUSPEND config option · af3cfdbf
      Lorenzo Pieralisi authored
      ARM64_CPU_SUSPEND config option was introduced to make code providing
      context save/restore selectable only on platforms requiring power
      management capabilities.
      
      Currently ARM64_CPU_SUSPEND depends on the PM_SLEEP config option which
      in turn is set by the SUSPEND config option.
      
      The introduction of CPU_IDLE for arm64 requires that code configured
      by ARM64_CPU_SUSPEND (context save/restore) should be compiled in
      in order to enable the CPU idle driver to rely on CPU operations
      carrying out context save/restore.
      
      The ARM64_CPUIDLE config option (ARM64 generic idle driver) is therefore
      forced to select ARM64_CPU_SUSPEND, even if there may be (ie PM_SLEEP)
      failed dependencies, which is not a clean way of handling the kernel
      configuration option.
      
      For these reasons, this patch removes the ARM64_CPU_SUSPEND config option
      and makes the context save/restore dependent on CPU_PM, which is selected
      whenever either SUSPEND or CPU_IDLE are configured, cleaning up dependencies
      in the process.
      
      This way, code previously configured through ARM64_CPU_SUSPEND is
      compiled in whenever a power management subsystem requires it to be
      present in the kernel (SUSPEND || CPU_IDLE), which is the behaviour
      expected on ARM64 kernels.
      
      The cpu_suspend and cpu_init_idle CPU operations are added only if
      CPU_IDLE is selected, since they are CPU_IDLE specific methods and
      should be grouped and defined accordingly.
      
      PSCI CPU operations are updated to reflect the introduced changes.
      Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
      Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      af3cfdbf
    • Catalin Marinas's avatar
      arm64: Implement the compat_sys_call_table in C · 0156411b
      Catalin Marinas authored
      Unlike the sys_call_table[], the compat one was implemented in sys32.S
      making it impossible to notice discrepancies between the number of
      compat syscalls and the __NR_compat_syscalls macro, the latter having to
      be defined in asm/unistd.h as including asm/unistd32.h would cause
      conflicts on __NR_* definitions. With this patch, incorrect
      __NR_compat_syscalls values will result in a build-time error.
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Suggested-by: default avatarMark Rutland <mark.rutland@arm.com>
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      0156411b
  16. 15 Jan, 2015 1 commit
  17. 25 Nov, 2014 2 commits
  18. 20 Nov, 2014 3 commits
  19. 30 Sep, 2014 1 commit
  20. 12 Sep, 2014 1 commit
  21. 18 Jul, 2014 2 commits
  22. 29 May, 2014 2 commits
    • AKASHI Takahiro's avatar
      arm64: ftrace: Add CALLER_ADDRx macros · 3711784e
      AKASHI Takahiro authored
      CALLER_ADDRx returns caller's address at specified level in call stacks.
      They are used for several tracers like irqsoff and preemptoff.
      Strange to say, however, they are refered even without FTRACE.
      Signed-off-by: default avatarAKASHI Takahiro <takahiro.akashi@linaro.org>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      3711784e
    • AKASHI Takahiro's avatar
      arm64: Add ftrace support · 819e50e2
      AKASHI Takahiro authored
      This patch implements arm64 specific part to support function tracers,
      such as function (CONFIG_FUNCTION_TRACER), function_graph
      (CONFIG_FUNCTION_GRAPH_TRACER) and function profiler
      (CONFIG_FUNCTION_PROFILER).
      
      With 'function' tracer, all the functions in the kernel are traced with
      timestamps in ${sysfs}/tracing/trace. If function_graph tracer is
      specified, call graph is generated.
      
      The kernel must be compiled with -pg option so that _mcount() is inserted
      at the beginning of functions. This function is called on every function's
      entry as long as tracing is enabled.
      In addition, function_graph tracer also needs to be able to probe function's
      exit. ftrace_graph_caller() & return_to_handler do this by faking link
      register's value to intercept function's return path.
      
      More details on architecture specific requirements are described in
      Documentation/trace/ftrace-design.txt.
      Reviewed-by: default avatarGanapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
      Acked-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarAKASHI Takahiro <takahiro.akashi@linaro.org>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      819e50e2
  23. 30 Apr, 2014 2 commits
  24. 24 Apr, 2014 1 commit
  25. 13 Mar, 2014 1 commit
  26. 04 Mar, 2014 1 commit
    • Mark Brown's avatar
      arm64: topology: Implement basic CPU topology support · f6e763b9
      Mark Brown authored
      Add basic CPU topology support to arm64, based on the existing pre-v8
      code and some work done by Mark Hambleton.  This patch does not
      implement any topology discovery support since that should be based on
      information from firmware, it merely implements the scaffolding for
      integration of topology support in the architecture.
      
      No locking of the topology data is done since it is only modified during
      CPU bringup with external serialisation from the SMP code.
      
      The goal is to separate the architecture hookup for providing topology
      information from the DT parsing in order to ease review and avoid
      blocking the architecture code (which will be built on by other work)
      with the DT code review by providing something simple and basic.
      
      Following patches will implement support for interpreting topology
      information from MPIDR and for parsing the DT topology bindings for ARM,
      similar patches will be needed for ACPI.
      Signed-off-by: default avatarMark Brown <broonie@linaro.org>
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      [catalin.marinas@arm.com: removed CONFIG_CPU_TOPOLOGY, always on if SMP]
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      f6e763b9
  27. 26 Feb, 2014 1 commit
  28. 08 Jan, 2014 2 commits