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2017-11-02arm64: Move the async/fiq helpers to explicitly set process context flagsJames Morse
Remove the local_{async,fiq}_{en,dis}able macros as they don't respect our newly defined order and are only used to set the flags for process context when we bring CPUs online. Add a helper to do this. The IRQ flag varies as we want it masked on the boot CPU until we are ready to handle interrupts. The boot CPU unmasks SError during early boot once it can print an error message. If we can print an error message about SError, we can do the same for FIQ. Debug exceptions are already enabled by __cpu_setup(), which has also configured MDSCR_EL1 to disable MDE and KDE. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-04arm64: consistently log boot/secondary CPU IDsMark Rutland
Currently we inconsistently log identifying information for the boot CPU and secondary CPUs. For the boot CPU, we log the MIDR and MPIDR across separate messages, whereas for the secondary CPUs we only log the MIDR. In some cases, it would be useful to know the MPIDR of secondary CPUs, and it would be nice for these messages to be consistent. This patch ensures that in the primary and secondary boot paths, we log both the MPIDR and MIDR in a single message, with a consistent format. the MPIDR is consistently padded to 10 hex characters to cover Aff3 in bits 39:32, so that IDs can be compared easily. The newly redundant message in setup_arch() is removed. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Al Stone <ahs3@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [will: added '0x' prefixes consistently] Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-02arm64: remove unneeded copy to init_utsname()->machineMasahiro Yamada
As you see in init/version.c, init_uts_ns.name.machine is initially set to UTS_MACHINE. There is no point to copy the same string. I dug the git history to figure out why this line is here. My best guess is like this: - This line has been around here since the initial support of arm64 by commit 9703d9d7f77c ("arm64: Kernel booting and initialisation"). If ARCH (=arm64) and UTS_MACHINE (=aarch64) do not match, arch/$(ARCH)/Makefile is supposed to override UTS_MACHINE, but the initial version of arch/arm64/Makefile missed to do that. Instead, the boot code copied "aarch64" to init_utsname()->machine. - Commit 94ed1f2cb5d4 ("arm64: setup: report ELF_PLATFORM as the machine for utsname") replaced "aarch64" with ELF_PLATFORM to make "uname" to reflect the endianness. - ELF_PLATFORM does not help to provide the UTS machine name to rpm target, so commit cfa88c79462d ("arm64: Set UTS_MACHINE in the Makefile") fixed it. The commit simply replaced ELF_PLATFORM with UTS_MACHINE, but missed the fact the string copy itself is no longer needed. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-05-30arm64: check return value of of_flat_dt_get_machine_nameKefeng Wang
It's useless to print machine name and setup arch-specific system identifiers if of_flat_dt_get_machine_name() return NULL, especially when ACPI-based boot. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-04-28arm64: Print DT machine model in setup_machine_fdt()Geert Uytterhoeven
On arm32, the machine model specified in the device tree is printed during boot-up, courtesy of of_flat_dt_match_machine(). On arm64, of_flat_dt_match_machine() is not called, and the machine model information is not available from the kernel log. Print the machine model to make it easier to derive the machine model from an arbitrary kernel boot log. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-05arm64: kdump: reserve memory for crash dump kernelAKASHI Takahiro
"crashkernel=" kernel parameter specifies the size (and optionally the start address) of the system ram to be used by crash dump kernel. reserve_crashkernel() will allocate and reserve that memory at boot time of primary kernel. The memory range will be exposed to userspace as a resource named "Crash kernel" in /proc/iomem. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Mark Salter <msalter@redhat.com> Signed-off-by: Pratyush Anand <panand@redhat.com> Reviewed-by: James Morse <james.morse@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-02sched/headers: Prepare to move 'init_task' and 'init_thread_union' from ↵Ingo Molnar
<linux/sched.h> to <linux/sched/task.h> Update all usage sites first. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-26arm64: kernel: do not mark reserved memory regions as IORESOURCE_BUSYArd Biesheuvel
Memory regions marked as NOMAP should not be used for general allocation by the kernel, and should not even be covered by the linear mapping (hence the name). However, drivers or other subsystems (such as ACPI) that access the firmware directly may legally access them, which means it is also reasonable for such drivers to claim them by invoking request_resource(). Currently, this is prevented by the fact that arm64's request_standard_resources() marks reserved regions as IORESOURCE_BUSY. So drop the IORESOURCE_BUSY flag from these requests. Reported-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-26arm64: Use __pa_symbol for empty_zero_pageGeert Uytterhoeven
If CONFIG_DEBUG_VIRTUAL=y and CONFIG_ARM64_SW_TTBR0_PAN=y: virt_to_phys used for non-linear address: ffffff8008cc0000 (empty_zero_page+0x0/0x1000) WARNING: CPU: 0 PID: 0 at arch/arm64/mm/physaddr.c:14 __virt_to_phys+0x28/0x60 ... [<ffffff800809abb4>] __virt_to_phys+0x28/0x60 [<ffffff8008a02600>] setup_arch+0x46c/0x4d4 Fixes: 2077be6783b5936c ("arm64: Use __pa_symbol for kernel symbols") Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-12arm64: Use __pa_symbol for kernel symbolsLaura Abbott
__pa_symbol is technically the marcro that should be used for kernel symbols. Switch to this as a pre-requisite for DEBUG_VIRTUAL which will do bounds checking. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-12-20arm64: setup: introduce kaslr_offset()Alexander Popov
Introduce kaslr_offset() similar to x86_64 to fix kcov. [ Updated by Will Deacon ] Link: http://lkml.kernel.org/r/1481417456-28826-2-git-send-email-alex.popov@linux.com Signed-off-by: Alexander Popov <alex.popov@linux.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh@kernel.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Jon Masters <jcm@redhat.com> Cc: David Daney <david.daney@cavium.com> Cc: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Nicolai Stange <nicstange@gmail.com> Cc: James Morse <james.morse@arm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Alexander Popov <alex.popov@linux.com> Cc: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-21arm64: Disable TTBR0_EL1 during normal kernel executionCatalin Marinas
When the TTBR0 PAN feature is enabled, the kernel entry points need to disable access to TTBR0_EL1. The PAN status of the interrupted context is stored as part of the saved pstate, reusing the PSR_PAN_BIT (22). Restoring access to TTBR0_EL1 is done on exception return if returning to user or returning to a context where PAN was disabled. Context switching via switch_mm() must defer the update of TTBR0_EL1 until a return to user or an explicit uaccess_enable() call. Special care needs to be taken for two cases where TTBR0_EL1 is set outside the normal kernel context switch operation: EFI run-time services (via efi_set_pgd) and CPU suspend (via cpu_(un)install_idmap). Code has been added to avoid deferred TTBR0_EL1 switching as in switch_mm() and restore the reserved TTBR0_EL1 when uninstalling the special TTBR0_EL1. User cache maintenance (user_cache_maint_handler and __flush_cache_user_range) needs the TTBR0_EL1 re-instated since the operations are performed by user virtual address. This patch also removes a stale comment on the switch_mm() function. Cc: Will Deacon <will.deacon@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-08-31arm64: Set UTS_MACHINE in the MakefileMichal Marek
The make rpm target depends on proper UTS_MACHINE definition. Also, use the variable in arch/arm64/kernel/setup.c, so that it's not accidentally removed in the future. Reported-and-tested-by: Fabian Vogt <fvogt@suse.com> Signed-off-by: Michal Marek <mmarek@suse.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-25arm64: mark reserved memblock regions explicitly in iomemAKASHI Takahiro
Kdump(kexec-tools) parses /proc/iomem to identify all the memory regions on the system. Since the current kernel names "nomap" regions, like UEFI runtime services code/data, as "System RAM," kexec-tools sets up elf core header to include them in a crash dump file (/proc/vmcore). Then crash dump kernel parses UEFI memory map again, re-marks those regions as "nomap" and does not create a memory mapping for them unlike the other areas of System RAM. In this case, copying /proc/vmcore through copy_oldmem_page() on crash dump kernel will end up with a kernel abort, as reported in [1]. This patch names all the "nomap" regions explicitly as "reserved" so that we can exclude them from a crash dump file. acpi_os_ioremap() must also be modified because those regions have WB attributes [2]. Apart from kdump, this change also matches x86's use of acpi (and /proc/iomem). [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-August/448186.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-August/450089.html Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: James Morse <james.morse@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-30Merge tag 'devicetree-for-4.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull DeviceTree updates from Rob Herring: - remove most of_platform_populate() calls in arch code. Now the DT core code calls it in the default case and platforms only need to call it if they have special needs - use pr_fmt on all the DT core print statements - CoreSight binding doc improvements to block name descriptions - add dt_to_config script which can parse dts files and list corresponding kernel config options - fix memory leak hit with a PowerMac DT - correct a bunch of STMicro compatible strings to use the correct vendor prefix - fix DA9052 PMIC binding doc to match what is actually used in dts files * tag 'devicetree-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (35 commits) documentation: da9052: Update regulator bindings names to match DA9052/53 DTS expectations xtensa: Partially Revert "xtensa: Remove unnecessary of_platform_populate with default match table" xtensa: Fix build error due to missing include file MIPS: ath79: Add missing include file Fix spelling errors in Documentation/devicetree ARM: dts: fix STMicroelectronics compatible strings powerpc/dts: fix STMicroelectronics compatible strings Documentation: dt: i2c: use correct STMicroelectronics vendor prefix scripts/dtc: dt_to_config - kernel config options for a devicetree of: fdt: mark unflattened tree as detached of: overlay: add resolver error prints coresight: document binding acronyms Documentation/devicetree: document cavium-pip rx-delay/tx-delay properties of: use pr_fmt prefix for all console printing of/irq: Mark initialised interrupt controllers as populated of: fix memory leak related to safe_name() Revert "of/platform: export of_default_bus_match_table" of: unittest: use of_platform_default_populate() to populate default bus memory: omap-gpmc: use of_platform_default_populate() to populate default bus bus: uniphier-system-bus: use of_platform_default_populate() to populate default bus ...
2016-07-27Merge tag 'for-linus-4.8-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from David Vrabel: "Features and fixes for 4.8-rc0: - ACPI support for guests on ARM platforms. - Generic steal time support for arm and x86. - Support cases where kernel cpu is not Xen VCPU number (e.g., if in-guest kexec is used). - Use the system workqueue instead of a custom workqueue in various places" * tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits) xen: add static initialization of steal_clock op to xen_time_ops xen/pvhvm: run xen_vcpu_setup() for the boot CPU xen/evtchn: use xen_vcpu_id mapping xen/events: fifo: use xen_vcpu_id mapping xen/events: use xen_vcpu_id mapping in events_base x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op xen: introduce xen_vcpu_id mapping x86/acpi: store ACPI ids from MADT for future usage x86/xen: update cpuid.h from Xen-4.7 xen/evtchn: add IOCTL_EVTCHN_RESTRICT xen-blkback: really don't leak mode property xen-blkback: constify instance of "struct attribute_group" xen-blkfront: prefer xenbus_scanf() over xenbus_gather() xen-blkback: prefer xenbus_scanf() over xenbus_gather() xen: support runqueue steal time on xen arm/xen: add support for vm_assist hypercall xen: update xen headers xen-pciback: drop superfluous variables xen-pciback: short-circuit read path used for merging write values ...
2016-07-27Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Kexec support for arm64 - Kprobes support - Expose MIDR_EL1 and REVIDR_EL1 CPU identification registers to sysfs - Trapping of user space cache maintenance operations and emulation in the kernel (CPU errata workaround) - Clean-up of the early page tables creation (kernel linear mapping, EFI run-time maps) to avoid splitting larger blocks (e.g. pmds) into smaller ones (e.g. ptes) - VDSO support for CLOCK_MONOTONIC_RAW in clock_gettime() - ARCH_HAS_KCOV enabled for arm64 - Optimise IP checksum helpers - SWIOTLB optimisation to only allocate/initialise the buffer if the available RAM is beyond the 32-bit mask - Properly handle the "nosmp" command line argument - Fix for the initialisation of the CPU debug state during early boot - vdso-offsets.h build dependency workaround - Build fix when RANDOMIZE_BASE is enabled with MODULES off * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (64 commits) arm64: arm: Fix-up the removal of the arm64 regs_query_register_name() prototype arm64: Only select ARM64_MODULE_PLTS if MODULES=y arm64: mm: run pgtable_page_ctor() on non-swapper translation table pages arm64: mm: make create_mapping_late() non-allocating arm64: Honor nosmp kernel command line option arm64: Fix incorrect per-cpu usage for boot CPU 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 arm64: debug: remove unused local_dbg_{enable, disable} macros arm64: debug: remove redundant spsr manipulation arm64: debug: unmask PSTATE.D earlier arm64: localise Image objcopy flags arm64: ptrace: remove extra define for CPSR's E bit 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 ...
2016-07-06ARM: XEN: Move xen_early_init() before efi_init()Shannon Zhao
Move xen_early_init() before efi_init(), then when calling efi_init() could initialize Xen specific UEFI. Check if it runs on Xen hypervisor through the flat dts. Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Julien Grall <julien.grall@arm.com> Tested-by: Julien Grall <julien.grall@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-27arm64: mm: fix location of _etextArd Biesheuvel
As Kees Cook notes in the ARM counterpart of this patch [0]: The _etext position is defined to be the end of the kernel text code, and should not include any part of the data segments. This interferes with things that might check memory ranges and expect executable code up to _etext. In particular, Kees is referring to the HARDENED_USERCOPY patch set [1], which rejects attempts to call copy_to_user() on kernel ranges containing executable code, but does allow access to the .rodata segment. Regardless of whether one may or may not agree with the distinction, it makes sense for _etext to have the same meaning across architectures. So let's put _etext where it belongs, between .text and .rodata, and fix up existing references to use __init_begin instead, which unlike _end_rodata includes the exception and notes sections as well. The _etext references in kaslr.c are left untouched, since its references to [_stext, _etext) are meant to capture potential jump instruction targets, and so disregarding .rodata is actually an improvement here. [0] http://article.gmane.org/gmane.linux.kernel/2245084 [1] http://thread.gmane.org/gmane.linux.kernel.hardened.devel/2502 Reported-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-23arm64: Remove unnecessary of_platform_populate with default match tableKefeng Wang
After patch "of/platform: Add common method to populate default bus", it is possible for arch code to remove unnecessary callers of of_platform_populate with default match table. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Rob Herring <robh@kernel.org>
2016-06-23of: iommu: make of_iommu_init() postcore_initcall_syncKefeng Wang
The of_iommu_init() is called multiple times by arch code, make it postcore_initcall_sync, then we can drop relevant calls fully. Note, the IOMMUs should have a chance to perform some basic initialisation before we start adding masters to them. So postcore_initcall_sync is good choice, it ensures of_iommu_init() called before of_platform_populate. Acked-by: Rich Felker <dalias@libc.org> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Rob Herring <robh@kernel.org>
2016-06-22ACPI: ARM64: support for ACPI_TABLE_UPGRADEJon Masters
This patch adds support for ACPI_TABLE_UPGRADE for ARM64 To access initrd image we need to move initialization of linear mapping a bit earlier. The implementation of the feature acpi_table_upgrade() (drivers/acpi/tables.c) works with initrd data represented as an array in virtual memory. It uses some library utility to find the redefined tables in that array and iterates over it to copy the data to new allocated memory. So to access the initrd data via fixmap we need to rewrite it considerably. In x86 arch, kernel memory is already mapped by the time when acpi_table_upgrade() and acpi_boot_table_init() are called so I think that we can just move this mapping one function earlier too. Signed-off-by: Jon Masters <jcm@redhat.com> Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-28arm64: Change cpu_resume() to enable mmu early then access sleep_sp by vaJames Morse
By enabling the MMU early in cpu_resume(), the sleep_save_sp and stack can be accessed by VA, which avoids the need to convert-addresses and clean to PoC on the suspend path. MMU setup is shared with the boot path, meaning the swapper_pg_dir is restored directly: ttbr1_el1 is no longer saved/restored. struct sleep_save_sp is removed, replacing it with a single array of pointers. cpu_do_{suspend,resume} could be further reduced to not restore: cpacr_el1, mdscr_el1, tcr_el1, vbar_el1 and sctlr_el1, all of which are set by __cpu_setup(). However these values all contain res0 bits that may be used to enable future features. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-15arm64, numa: Add NUMA support for arm64 platforms.Ganapatrao Kulkarni
Attempt to get the memory and CPU NUMA node via of_numa. If that fails, default the dummy NUMA node and map all memory and CPUs to node 0. Tested-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-15arm64: Move unflatten_device_tree() call earlier.David Daney
In order to extract NUMA information from the device tree, we need to have the tree in its unflattened form. Move the call to bootmem_init() in the tail of paging_init() into setup_arch, and adjust header files so that its declaration is visible. Move the unflatten_device_tree() call between the calls to paging_init() and bootmem_init(). Follow on patches add NUMA handling to bootmem_init(). Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-14arm64: remove the now unneeded relocate_initrd()Ard Biesheuvel
This removes the relocate_initrd() implementation and invocation, which are no longer needed now that the placement of the initrd is guaranteed to be covered by the linear mapping. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-17Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Here are the main arm64 updates for 4.6. There are some relatively intrusive changes to support KASLR, the reworking of the kernel virtual memory layout and initial page table creation. Summary: - Initial page table creation reworked to avoid breaking large block mappings (huge pages) into smaller ones. The ARM architecture requires break-before-make in such cases to avoid TLB conflicts but that's not always possible on live page tables - Kernel virtual memory layout: the kernel image is no longer linked to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of the vmalloc space, allowing the kernel to be loaded (nearly) anywhere in physical RAM - Kernel ASLR: position independent kernel Image and modules being randomly mapped in the vmalloc space with the randomness is provided by UEFI (efi_get_random_bytes() patches merged via the arm64 tree, acked by Matt Fleming) - Implement relative exception tables for arm64, required by KASLR (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but actual x86 conversion to deferred to 4.7 because of the merge dependencies) - Support for the User Access Override feature of ARMv8.2: this allows uaccess functions (get_user etc.) to be implemented using LDTR/STTR instructions. Such instructions, when run by the kernel, perform unprivileged accesses adding an extra level of protection. The set_fs() macro is used to "upgrade" such instruction to privileged accesses via the UAO bit - Half-precision floating point support (part of ARMv8.2) - Optimisations for CPUs with or without a hardware prefetcher (using run-time code patching) - copy_page performance improvement to deal with 128 bytes at a time - Sanity checks on the CPU capabilities (via CPUID) to prevent incompatible secondary CPUs from being brought up (e.g. weird big.LITTLE configurations) - valid_user_regs() reworked for better sanity check of the sigcontext information (restored pstate information) - ACPI parking protocol implementation - CONFIG_DEBUG_RODATA enabled by default - VDSO code marked as read-only - DEBUG_PAGEALLOC support - ARCH_HAS_UBSAN_SANITIZE_ALL enabled - Erratum workaround Cavium ThunderX SoC - set_pte_at() fix for PROT_NONE mappings - Code clean-ups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits) arm64: kasan: Fix zero shadow mapping overriding kernel image shadow arm64: kasan: Use actual memory node when populating the kernel image shadow arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission arm64: Fix misspellings in comments. arm64: efi: add missing frame pointer assignment arm64: make mrs_s prefixing implicit in read_cpuid arm64: enable CONFIG_DEBUG_RODATA by default arm64: Rework valid_user_regs arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly arm64: KVM: Move kvm_call_hyp back to its original localtion arm64: mm: treat memstart_addr as a signed quantity arm64: mm: list kernel sections in order arm64: lse: deal with clobbered IP registers after branch via PLT arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR arm64: kconfig: add submenu for 8.2 architectural features arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot arm64: Add support for Half precision floating point arm64: Remove fixmap include fragility arm64: Add workaround for Cavium erratum 27456 arm64: mm: Mark .rodata as RO ...
2016-02-24arm64: add support for kernel ASLRArd Biesheuvel
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: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16arm64: unmap idmap earlierMark Rutland
During boot we leave the idmap in place until paging_init, as we previously had to wait for the zero page to become allocated and accessible. Now that we have a statically-allocated zero page, we can uninstall the idmap much earlier in the boot process, making it far easier to spot accidental use of physical addresses. This also brings the cold boot path in line with the secondary boot path. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16arm64: unify idmap removalMark Rutland
We currently open-code the removal of the idmap and restoration of the current task's MMU state in a few places. Before introducing yet more copies of this sequence, unify these to call a new helper, cpu_uninstall_idmap. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-30arch: Set IORESOURCE_SYSTEM_RAM flag for System RAMToshi Kani
Set IORESOURCE_SYSTEM_RAM in flags of resource ranges with "System RAM", "Kernel code", "Kernel data", and "Kernel bss". Note that: - IORESOURCE_SYSRAM (i.e. modifier bit) is set in flags when IORESOURCE_MEM is already set. IORESOURCE_SYSTEM_RAM is defined as (IORESOURCE_MEM|IORESOURCE_SYSRAM). - Some archs do not set 'flags' for children nodes, such as "Kernel code". This patch does not change 'flags' in this case. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@linux-mips.org Cc: linux-mm <linux-mm@kvack.org> Cc: linux-parisc@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/1453841853-11383-7-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-04Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - "genirq: Introduce generic irq migration for cpu hotunplugged" patch merged from tip/irq/for-arm to allow the arm64-specific part to be upstreamed via the arm64 tree - CPU feature detection reworked to cope with heterogeneous systems where CPUs may not have exactly the same features. The features reported by the kernel via internal data structures or ELF_HWCAP are delayed until all the CPUs are up (and before user space starts) - Support for 16KB pages, with the additional bonus of a 36-bit VA space, though the latter only depending on EXPERT - Implement native {relaxed, acquire, release} atomics for arm64 - New ASID allocation algorithm which avoids IPI on roll-over, together with TLB invalidation optimisations (using local vs global where feasible) - KASan support for arm64 - EFI_STUB clean-up and isolation for the kernel proper (required by KASan) - copy_{to,from,in}_user optimisations (sharing the memcpy template) - perf: moving arm64 to the arm32/64 shared PMU framework - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware - Support for the contiguous PTE hint on kernel mapping (16 consecutive entries may be able to use a single TLB entry) - Generic CONFIG_HZ now used on arm64 - defconfig updates * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits) arm64/efi: fix libstub build under CONFIG_MODVERSIONS ARM64: Enable multi-core scheduler support by default arm64/efi: move arm64 specific stub C code to libstub arm64: page-align sections for DEBUG_RODATA arm64: Fix build with CONFIG_ZONE_DMA=n arm64: Fix compat register mappings arm64: Increase the max granular size arm64: remove bogus TASK_SIZE_64 check arm64: make Timer Interrupt Frequency selectable arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED arm64: cachetype: fix definitions of ICACHEF_* flags arm64: cpufeature: declare enable_cpu_capabilities as static genirq: Make the cpuhotplug migration code less noisy arm64: Constify hwcap name string arrays arm64/kvm: Make use of the system wide safe values arm64/debug: Make use of the system wide safe value arm64: Move FP/ASIMD hwcap handling to common code arm64/HWCAP: Use system wide safe values arm64/capabilities: Make use of system wide safe value arm64: Delay cpu feature capability checks ...
2015-10-21arm64: Move /proc/cpuinfo handling codeSuzuki K. Poulose
This patch moves the /proc/cpuinfo handling code: arch/arm64/kernel/{setup.c to cpuinfo.c} No functional changes Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Move cpu feature detection codeSuzuki K. Poulose
This patch moves the CPU feature detection code from arch/arm64/kernel/{setup.c to cpufeature.c} The plan is to consolidate all the CPU feature handling in cpufeature.c. Apart from changing pr_fmt from "alternatives" to "cpu features", there are no functional changes. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Delay cpuinfo_store_boot_cpuSuzuki K. Poulose
At the moment the boot CPU stores the cpuinfo long before the PERCPU areas are initialised by the kernel. This could be problematic as the non-boot CPU data structures might get copied with the data from the boot CPU, giving us no chance to detect if a particular CPU updated its cpuinfo. This patch delays the boot cpu store to smp_prepare_boot_cpu(). Also kills the setup_processor() which no longer does meaningful work. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Delay ELF HWCAP initialisation until all CPUs are upSuzuki K. Poulose
Delay the ELF HWCAP initialisation until all the (enabled) CPUs are up, i.e, smp_cpus_done(). This is in preparation for detecting the common features across the CPUS and creating a consistent ELF HWCAP for the system. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Make the CPU information more clearSuzuki K. Poulose
At early boot, we print the CPU version/revision. On a heterogeneous system, we could have different types of CPUs. Print the CPU info for all active cpus. Also, the secondary CPUs prints the message only when they turn online. Also, remove the redundant 'revision' information which doesn't make any sense without the 'variant' field. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-12arm64: add KASAN supportAndrey Ryabinin
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: Andrey Ryabinin <ryabinin.a.a@gmail.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-06arm64: Don't relocate non-existent initrdMark Rutland
When booting a kernel without an initrd, the kernel reports that it moves -1 bytes worth, having gone through the motions with initrd_start equal to initrd_end: Moving initrd from [4080000000-407fffffff] to [9fff49000-9fff48fff] Prevent this by bailing out early when the initrd size is zero (i.e. we have no initrd), avoiding the confusing message and other associated work. Fixes: 1570f0d7ab425c1e ("arm64: support initrd outside kernel linear map") Cc: Mark Salter <msalter@redhat.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-09-08arm64: support initrd outside kernel linear mapMark Salter
The use of mem= could leave part or all of the initrd outside of the kernel linear map. This will lead to an error when unpacking the initrd and a probable failure to boot. This patch catches that situation and relocates the initrd to be fully within the linear map. Signed-off-by: Mark Salter <msalter@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: - Support for new architectural features introduced in ARMv8.1: * Privileged Access Never (PAN) to catch user pointer dereferences in the kernel * Large System Extension (LSE) for building scalable atomics and locks (depends on locking/arch-atomic from tip, which is included here) * Hardware Dirty Bit Management (DBM) for updating clean PTEs automatically - Move our PSCI implementation out into drivers/firmware/, where it can be shared with arch/arm/. RMK has also pulled this component branch and has additional patches moving arch/arm/ over. MAINTAINERS is updated accordingly. - Better BUG implementation based on the BRK instruction for trapping - Leaf TLB invalidation for unmapping user pages - Support for PROBE_ONLY PCI configurations - Various cleanups and non-critical fixes, including: * Always flush FP/SIMD state over exec() * Restrict memblock additions based on range of linear mapping * Ensure *(LIST_POISON) generates a fatal fault * Context-tracking syscall return no longer corrupts return value when not forced on. * Alternatives patching synchronisation/stability improvements * Signed sub-word cmpxchg compare fix (tickled by HAVE_CMPXCHG_LOCAL) * Force SMP=y * Hide direct DCC access from userspace * Fix EFI stub memory allocation when DRAM starts at 0x0 * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) arm64: flush FP/SIMD state correctly after execve() arm64: makefile: fix perf_callchain.o kconfig dependency arm64: set MAX_MEMBLOCK_ADDR according to linear region size of/fdt: make memblock maximum physical address arch configurable arm64: Fix source code file path in comments arm64: entry: always restore x0 from the stack on syscall return arm64: mdscr_el1: avoid exposing DCC to userspace arm64: kconfig: Move LIST_POISON to a safe value arm64: Add __exception_irq_entry definition for function graph arm64: mm: ensure patched kernel text is fetched from PoU arm64: alternatives: ensure secondary CPUs execute ISB after patching arm64: make ll/sc __cmpxchg_case_##name asm consistent arm64: dma-mapping: Simplify pgprot handling arm64: restore cpu suspend/resume functionality ARM64: PCI: do not enable resources on PROBE_ONLY systems arm64: cmpxchg: truncate sub-word signed types before comparison arm64: alternative: put secondary CPUs into polling loop during patch arm64/Documentation: clarify wording regarding memory below the Image arm64: lse: fix lse cmpxchg code indentation arm64: remove redundant object file list ...
2015-09-03Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM development updates from Russell King: "Included in this update: - moving PSCI code from ARM64/ARM to drivers/ - removal of some architecture internals from global kernel view - addition of software based "privileged no access" support using the old domains register to turn off the ability for kernel loads/stores to access userspace. Only the proper accessors will be usable. - addition of early fixup support for early console - re-addition (and reimplementation) of OMAP special interconnect barrier - removal of finish_arch_switch() - only expose cpuX/online in sysfs if hotpluggable - a number of code cleanups" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits) ARM: software-based priviledged-no-access support ARM: entry: provide uaccess assembly macro hooks ARM: entry: get rid of multiple macro definitions ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die() ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore() ARM: mm: improve do_ldrd_abort macro ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit() ARM: entry: efficiency cleanups ARM: entry: get rid of asm_trace_hardirqs_on_cond ARM: uaccess: simplify user access assembly ARM: domains: remove DOMAIN_TABLE ARM: domains: keep vectors in separate domain ARM: domains: get rid of manager mode for user domain ARM: domains: move initial domain setting value to asm/domains.h ARM: domains: provide domain_mask() ARM: domains: switch to keeping domain value in register ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD() ARM: 8416/1: Feroceon: use of_iomap() to map register base ARM: 8415/1: early fixmap support for earlycon ...
2015-08-05Merge branch 'aarch64/psci/drivers' into aarch64/for-next/coreWill Deacon
Move our PSCI implementation out into drivers/firmware/ where it can be shared with arch/arm/. Conflicts: arch/arm64/kernel/psci.c
2015-08-03arm64: psci: factor invocation code to driversMark Rutland
To enable sharing with arm, move the core PSCI framework code to drivers/firmware. This results in a minor gain in lines of code, but this will quickly be amortised by the removal of code currently duplicated in arch/arm. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-29arm64: remove dead-code depending on CONFIG_UP_LATE_INITJonas Rabenstein
Commit 4b3dc9679cf7 ("arm64: force CONFIG_SMP=y and remove redundant and therfore can not be selected anymore. Remove dead #ifdef-block depending on UP_LATE_INIT in arch/arm64/kernel/setup.c Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de> [will: kill do_post_cpus_up_work altogether] Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: elf: use cpuid_feature_extract_field for hwcap detectionWill Deacon
cpuid_feature_extract_field takes care of the fiddly ID register field sign-extension, so use that instead of rolling our own version. Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: lse: use generic cpufeature detection for LSE atomicsWill Deacon
Rework the cpufeature detection to support ISAR0 and use that for detecting the presence of LSE atomics. Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: lse: rename ARM64_CPU_FEAT_LSE_ATOMICS for consistencyWill Deacon
Other CPU features follow an 'ARM64_HAS_*' naming scheme, so do the same for the LSE atomics. Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: atomics: patch in lse instructions when supported by the CPUWill Deacon
On CPUs which support the LSE atomic instructions introduced in ARMv8.1, it makes sense to use them in preference to ll/sc sequences. This patch introduces runtime patching of atomic_t and atomic64_t routines so that the call-site for the out-of-line ll/sc sequences is patched with an LSE atomic instruction when we detect that the CPU supports it. If binutils is not recent enough to assemble the LSE instructions, then the ll/sc sequences are inlined as though CONFIG_ARM64_LSE_ATOMICS=n. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-27arm64: alternatives: add cpu feature for lse atomicsWill Deacon
Add a CPU feature for the LSE atomic instructions, so that they can be patched in at runtime when we detect that they are supported. Reviewed-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>