1. 18 Nov, 2015 1 commit
  2. 17 Nov, 2015 4 commits
    • Lorenzo Pieralisi's avatar
      arm64: kernel: pause/unpause function graph tracer in cpu_suspend() · de818bd4
      Lorenzo Pieralisi authored
      The function graph tracer adds instrumentation that is required to trace
      both entry and exit of a function. In particular the function graph
      tracer updates the "return address" of a function in order to insert
      a trace callback on function exit.
      
      Kernel power management functions like cpu_suspend() are called
      upon power down entry with functions called "finishers" that are in turn
      called to trigger the power down sequence but they may not return to the
      kernel through the normal return path.
      
      When the core resumes from low-power it returns to the cpu_suspend()
      function through the cpu_resume path, which leaves the trace stack frame
      set-up by the function tracer in an incosistent state upon return to the
      kernel when tracing is enabled.
      
      This patch fixes the issue by pausing/resuming the function graph
      tracer on the thread executing cpu_suspend() (ie the function call that
      subsequently triggers the "suspend finishers"), so that the function graph
      tracer state is kept consistent across functions that enter power down
      states and never return by effectively disabling graph tracer while they
      are executing.
      
      Fixes: 819e50e2
      
       ("arm64: Add ftrace support")
      Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
      Reported-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Reported-by: default avatarAKASHI Takahiro <takahiro.akashi@linaro.org>
      Suggested-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: <stable@vger.kernel.org> # 3.16+
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      de818bd4
    • Arnd Bergmann's avatar
      arm64: do not include ptrace.h from compat.h · adc235af
      Arnd Bergmann authored
      
      
      including ptrace.h brings a definition of BITS_PER_PAGE into device
      drivers and cause a build warning in allmodconfig builds:
      
      drivers/block/drbd/drbd_bitmap.c:482:0: warning: "BITS_PER_PAGE" redefined
       #define BITS_PER_PAGE  (1UL << (PAGE_SHIFT + 3))
      
      This uses a slightly different way to express current_pt_regs()
      that avoids the use of the header and gets away with the already
      included asm/ptrace.h.
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      adc235af
    • Arnd Bergmann's avatar
      arm64: simplify dma_get_ops · 1dccb598
      Arnd Bergmann authored
      
      
      Including linux/acpi.h from asm/dma-mapping.h causes tons of compile-time
      warnings, e.g.
      
       drivers/isdn/mISDN/dsp_ecdis.h:43:0: warning: "FALSE" redefined
       drivers/isdn/mISDN/dsp_ecdis.h:44:0: warning: "TRUE" redefined
       drivers/net/fddi/skfp/h/targetos.h:62:0: warning: "TRUE" redefined
       drivers/net/fddi/skfp/h/targetos.h:63:0: warning: "FALSE" redefined
      
      However, it looks like the dependency should not even there as
      I do not see why __generic_dma_ops() cares about whether we have
      an ACPI based system or not.
      
      The current behavior is to fall back to the global dma_ops when
      a device has not set its own dma_ops, but only for DT based systems.
      This seems dangerous, as a random device might have different
      requirements regarding IOMMU or coherency, so we should really
      never have that fallback and just forbid DMA when we have not
      initialized DMA for a device.
      
      This removes the global dma_ops variable and the special-casing
      for ACPI, and just returns the dma ops that got set for the
      device, or the dummy_dma_ops if none were present.
      
      The original code has apparently been copied from arm32 where we
      rely on it for ISA devices things like the floppy controller, but
      we should have no such devices on ARM64.
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      [catalin.marinas@arm.com: removed acpi_disabled check in arch_setup_dma_ops()]
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      1dccb598
    • Ard Biesheuvel's avatar
      arm64: mm: use correct mapping granularity under DEBUG_RODATA · 4fee9f36
      Ard Biesheuvel authored
      When booting a 64k pages kernel that is built with CONFIG_DEBUG_RODATA
      and resides at an offset that is not a multiple of 512 MB, the rounding
      that occurs in __map_memblock() and fixup_executable() results in
      incorrect regions being mapped.
      
      The following snippet from /sys/kernel/debug/kernel_page_tables shows
      how, when the kernel is loaded 2 MB above the base of DRAM at 0x40000000,
      the first 2 MB of memory (which may be inaccessible from non-secure EL1
      or just reserved by the firmware) is inadvertently mapped into the end of
      the module region.
      
        ---[ Modules start ]---
        0xfffffdffffe00000-0xfffffe0000000000     2M RW NX ... UXN MEM/NORMAL
        ---[ Modules end ]---
        ---[ Kernel Mapping ]---
        0xfffffe0000000000-0xfffffe0000090000   576K RW NX ... UXN MEM/NORMAL
        0xfffffe0000090000-0xfffffe0000200000  1472K ro x  ... UXN MEM/NORMAL
        0xfffffe0000200000-0xfffffe0000800000     6M ro x  ... UXN MEM/NORMAL
        0xfffffe0000800000-0xfffffe0000810000    64K ro x  ... UXN MEM/NORMAL
        0xfffffe0000810000-0xfffffe0000a00000  1984K RW NX ... UXN MEM/NORMAL
        0xfffffe0000a00000-0xfffffe00ffe00000  4084M RW NX ... UXN MEM/NORMAL
      
      The same issue is likely to occur on 16k pages kernels whose load
      address is not a multiple of 32 MB (i.e., SECTION_SIZE). So round to
      SWAPPER_BLOCK_SIZE instead of SECTION_SIZE.
      
      Fixes: da141706
      
       ("arm64: add better page protections to arm64")
      Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      Acked-by: default avatarLaura Abbott <labbott@redhat.com>
      Cc: <stable@vger.kernel.org> # 4.0+
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      4fee9f36
  3. 16 Nov, 2015 1 commit
  4. 14 Nov, 2015 4 commits
  5. 12 Nov, 2015 12 commits
  6. 11 Nov, 2015 18 commits