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2017-09-08treewide: make "nr_cpu_ids" unsignedAlexey Dobriyan1-1/+1
First, number of CPUs can't be negative number. Second, different signnnedness leads to suboptimal code in the following cases: 1) kmalloc(nr_cpu_ids * sizeof(X)); "int" has to be sign extended to size_t. 2) while (loff_t *pos < nr_cpu_ids) MOVSXD is 1 byte longed than the same MOV. Other cases exist as well. Basically compiler is told that nr_cpu_ids can't be negative which can't be deduced if it is "int". Code savings on allyesconfig kernel: -3KB add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370) function old new delta coretemp_cpu_online 450 512 +62 rcu_init_one 1234 1272 +38 pci_device_probe 374 399 +25 ... pgdat_reclaimable_pages 628 556 -72 select_fallback_rq 446 369 -77 task_numa_find_cpu 1923 1807 -116 Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-21arm64: kexec: have own crash_smp_send_stop() for crash dump for nonpanic coresHoeun Ryu1-1/+11
Commit 0ee5941 : (x86/panic: replace smp_send_stop() with kdump friendly version in panic path) introduced crash_smp_send_stop() which is a weak function and can be overridden by architecture codes to fix the side effect caused by commit f06e515 : (kernel/panic.c: add "crash_kexec_post_ notifiers" option). ARM64 architecture uses the weak version function and the problem is that the weak function simply calls smp_send_stop() which makes other CPUs offline and takes away the chance to save crash information for nonpanic CPUs in machine_crash_shutdown() when crash_kexec_post_notifiers kernel option is enabled. Calling smp_send_crash_stop() in machine_crash_shutdown() is useless because all nonpanic CPUs are already offline by smp_send_stop() in this case and smp_send_crash_stop() only works against online CPUs. The result is that secondary CPUs registers are not saved by crash_save_cpu() and the vmcore file misreports these CPUs as being offline. crash_smp_send_stop() is implemented to fix this problem by replacing the existing smp_send_crash_stop() and adding a check for multiple calling to the function. The function (strong symbol version) saves crash information for nonpanic CPUs and machine_crash_shutdown() tries to save crash information for nonpanic CPUs only when crash_kexec_post_notifiers kernel option is disabled. * crash_kexec_post_notifiers : false panic() __crash_kexec() machine_crash_shutdown() crash_smp_send_stop() <= save crash dump for nonpanic cores * crash_kexec_post_notifiers : true panic() crash_smp_send_stop() <= save crash dump for nonpanic cores __crash_kexec() machine_crash_shutdown() crash_smp_send_stop() <= just return. Signed-off-by: Hoeun Ryu <hoeun.ryu@gmail.com> Reviewed-by: James Morse <james.morse@arm.com> Tested-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-15arm64: kernel: remove {THREAD,IRQ_STACK}_START_SPArd Biesheuvel1-1/+1
For historical reasons, we leave the top 16 bytes of our task and IRQ stacks unused, a practice used to ensure that the SP can always be masked to find the base of the current stack (historically, where thread_info could be found). However, this is not necessary, as: * When an exception is taken from a task stack, we decrement the SP by S_FRAME_SIZE and stash the exception registers before we compare the SP against the task stack. In such cases, the SP must be at least S_FRAME_SIZE below the limit, and can be safely masked to determine whether the task stack is in use. * When transitioning to an IRQ stack, we'll place a dummy frame onto the IRQ stack before enabling asynchronous exceptions, or executing code we expect to trigger faults. Thus, if an exception is taken from the IRQ stack, the SP must be at least 16 bytes below the limit. * We no longer mask the SP to find the thread_info, which is now found via sp_el0. Note that historically, the offset was critical to ensure that cpu_switch_to() found the correct stack for new threads that hadn't yet executed ret_from_fork(). Given that, this initial offset serves no purpose, and can be removed. This brings us in-line with other architectures (e.g. x86) which do not rely on this masking. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [Mark: rebase, kill THREAD_START_SP, commit msg additions] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com>
2017-07-20arm64: Convert to using %pOF instead of full_nameRob Herring1-6/+6
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-05-23arm64: Adjust system_state checkThomas Gleixner1-2/+1
To enable smp_processor_id() and might_sleep() debug checks earlier, it's required to add system states between SYSTEM_BOOTING and SYSTEM_RUNNING. Adjust the system_state check in smp_send_stop() to handle the extra states. Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/20170516184735.112589728@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-05Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-0/+79
Pull arm64 updates from Catalin Marinas: - kdump support, including two necessary memblock additions: memblock_clear_nomap() and memblock_cap_memory_range() - ARMv8.3 HWCAP bits for JavaScript conversion instructions, complex numbers and weaker release consistency - arm64 ACPI platform MSI support - arm perf updates: ACPI PMU support, L3 cache PMU in some Qualcomm SoCs, Cortex-A53 L2 cache events and DTLB refills, MAINTAINERS update for DT perf bindings - architected timer errata framework (the arch/arm64 changes only) - support for DMA_ATTR_FORCE_CONTIGUOUS in the arm64 iommu DMA API - arm64 KVM refactoring to use common system register definitions - remove support for ASID-tagged VIVT I-cache (no ARMv8 implementation using it and deprecated in the architecture) together with some I-cache handling clean-up - PE/COFF EFI header clean-up/hardening - define BUG() instruction without CONFIG_BUG * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) arm64: Fix the DMA mmap and get_sgtable API with DMA_ATTR_FORCE_CONTIGUOUS arm64: Print DT machine model in setup_machine_fdt() arm64: pmu: Wire-up Cortex A53 L2 cache events and DTLB refills arm64: module: split core and init PLT sections arm64: pmuv3: handle pmuv3+ arm64: Add CNTFRQ_EL0 trap handler arm64: Silence spurious kbuild warning on menuconfig arm64: pmuv3: use arm_pmu ACPI framework arm64: pmuv3: handle !PMUv3 when probing drivers/perf: arm_pmu: add ACPI framework arm64: add function to get a cpu's MADT GICC table drivers/perf: arm_pmu: split out platform device probe logic drivers/perf: arm_pmu: move irq request/free into probe drivers/perf: arm_pmu: split cpu-local irq request/free drivers/perf: arm_pmu: rename irq request/free functions drivers/perf: arm_pmu: handle no platform_device drivers/perf: arm_pmu: simplify cpu_pmu_request_irqs() drivers/perf: arm_pmu: factor out pmu registration drivers/perf: arm_pmu: fold init into alloc drivers/perf: arm_pmu: define armpmu_init_fn ...
2017-04-12Merge branch 'will/for-next/perf' into for-next/coreCatalin Marinas1-0/+10
* will/for-next/perf: arm64: pmuv3: use arm_pmu ACPI framework arm64: pmuv3: handle !PMUv3 when probing drivers/perf: arm_pmu: add ACPI framework arm64: add function to get a cpu's MADT GICC table drivers/perf: arm_pmu: split out platform device probe logic drivers/perf: arm_pmu: move irq request/free into probe drivers/perf: arm_pmu: split cpu-local irq request/free drivers/perf: arm_pmu: rename irq request/free functions drivers/perf: arm_pmu: handle no platform_device drivers/perf: arm_pmu: simplify cpu_pmu_request_irqs() drivers/perf: arm_pmu: factor out pmu registration drivers/perf: arm_pmu: fold init into alloc drivers/perf: arm_pmu: define armpmu_init_fn drivers/perf: arm_pmu: remove pointless PMU disabling perf: qcom: Add L3 cache PMU driver drivers/perf: arm_pmu: split irq request from enable drivers/perf: arm_pmu: manage interrupts per-cpu drivers/perf: arm_pmu: rework per-cpu allocation MAINTAINERS: Add file patterns for perf device tree bindings
2017-04-11arm64: add function to get a cpu's MADT GICC tableMark Rutland1-0/+10
Currently the ACPI parking protocol code needs to parse each CPU's MADT GICC table to extract the mailbox address and so on. Each time we parse a GICC table, we call back to the parking protocol code to parse it. This has been fine so far, but we're about to have more code that needs to extract data from the GICC tables, and adding a callback for each user is going to get unwieldy. Instead, this patch ensures that we stash a copy of each CPU's GICC table at boot time, such that anything needing to parse it can later request it. This will allow for other parsers of GICC, and for simplification to the ACPI parking protocol code. Note that we must store a copy, rather than a pointer, since the core ACPI code temporarily maps/unmaps tables while iterating over them. Since we parse the MADT before we know how many CPUs we have (and hence before we setup the percpu areas), we must use an NR_CPUS sized array. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-04-05arm64: kdump: implement machine_crash_shutdown()AKASHI Takahiro1-0/+68
Primary kernel calls machine_crash_shutdown() to shut down non-boot cpus and save registers' status in per-cpu ELF notes before starting crash dump kernel. See kernel_kexec(). Even if not all secondary cpus have shut down, we do kdump anyway. As we don't have to make non-boot(crashed) cpus offline (to preserve correct status of cpus at crash dump) before shutting down, this patch also adds a variant of smp_send_stop(). Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: James Morse <james.morse@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-30arm64: fix NULL dereference in have_cpu_die()Mark Salter1-1/+1
Commit 5c492c3f5255 ("arm64: smp: Add function to determine if cpus are stuck in the kernel") added a helper function to determine if die() is supported in cpu_ops. This function assumes a cpu will have a valid cpu_ops entry, but that may not be the case for cpu0 is spin-table or parking protocol is used to boot secondary cpus. In that case, there is a NULL dereference if have_cpu_die() is called by cpu0. So add a check for a valid cpu_ops before dereferencing it. Fixes: 5c492c3f5255 ("arm64: smp: Add function to determine if cpus are stuck in the kernel") Signed-off-by: Mark Salter <msalter@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-03-23arm64: alternatives: apply boot time fixups via the linear mappingArd Biesheuvel1-0/+1
One important rule of thumb when desiging a secure software system is that memory should never be writable and executable at the same time. We mostly adhere to this rule in the kernel, except at boot time, when regions may be mapped RWX until after we are done applying alternatives or making other one-off changes. For the alternative patching, we can improve the situation by applying the fixups via the linear mapping, which is never mapped with executable permissions. So map the linear alias of .text with RW- permissions initially, and remove the write permissions as soon as alternative patching has completed. Reviewed-by: Laura Abbott <labbott@redhat.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-03sched/headers: Move task->mm handling methods to <linux/sched/mm.h>Ingo Molnar1-1/+1
Move the following task->mm helper APIs into a new header file, <linux/sched/mm.h>, to further reduce the size and complexity of <linux/sched.h>. Here are how the APIs are used in various kernel files: # mm_alloc(): arch/arm/mach-rpc/ecard.c fs/exec.c include/linux/sched/mm.h kernel/fork.c # __mmdrop(): arch/arc/include/asm/mmu_context.h include/linux/sched/mm.h kernel/fork.c # mmdrop(): arch/arm/mach-rpc/ecard.c arch/m68k/sun3/mmu_emu.c arch/x86/mm/tlb.c drivers/gpu/drm/amd/amdkfd/kfd_process.c drivers/gpu/drm/i915/i915_gem_userptr.c drivers/infiniband/hw/hfi1/file_ops.c drivers/vfio/vfio_iommu_spapr_tce.c fs/exec.c fs/proc/base.c fs/proc/task_mmu.c fs/proc/task_nommu.c fs/userfaultfd.c include/linux/mmu_notifier.h include/linux/sched/mm.h kernel/fork.c kernel/futex.c kernel/sched/core.c mm/khugepaged.c mm/ksm.c mm/mmu_context.c mm/mmu_notifier.c mm/oom_kill.c virt/kvm/kvm_main.c # mmdrop_async_fn(): include/linux/sched/mm.h # mmdrop_async(): include/linux/sched/mm.h kernel/fork.c # mmget_not_zero(): fs/userfaultfd.c include/linux/sched/mm.h mm/oom_kill.c # mmput(): arch/arc/include/asm/mmu_context.h arch/arc/kernel/troubleshoot.c arch/frv/mm/mmu-context.c arch/powerpc/platforms/cell/spufs/context.c arch/sparc/include/asm/mmu_context_32.h drivers/android/binder.c drivers/gpu/drm/etnaviv/etnaviv_gem.c drivers/gpu/drm/i915/i915_gem_userptr.c drivers/infiniband/core/umem.c drivers/infiniband/core/umem_odp.c drivers/infiniband/core/uverbs_main.c drivers/infiniband/hw/mlx4/main.c drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/usnic/usnic_uiom.c drivers/iommu/amd_iommu_v2.c drivers/iommu/intel-svm.c drivers/lguest/lguest_user.c drivers/misc/cxl/fault.c drivers/misc/mic/scif/scif_rma.c drivers/oprofile/buffer_sync.c drivers/vfio/vfio_iommu_type1.c drivers/vhost/vhost.c drivers/xen/gntdev.c fs/exec.c fs/proc/array.c fs/proc/base.c fs/proc/task_mmu.c fs/proc/task_nommu.c fs/userfaultfd.c include/linux/sched/mm.h kernel/cpuset.c kernel/events/core.c kernel/events/uprobes.c kernel/exit.c kernel/fork.c kernel/ptrace.c kernel/sys.c kernel/trace/trace_output.c kernel/tsacct.c mm/memcontrol.c mm/memory.c mm/mempolicy.c mm/migrate.c mm/mmu_notifier.c mm/nommu.c mm/oom_kill.c mm/process_vm_access.c mm/rmap.c mm/swapfile.c mm/util.c virt/kvm/async_pf.c # mmput_async(): include/linux/sched/mm.h kernel/fork.c mm/oom_kill.c # get_task_mm(): arch/arc/kernel/troubleshoot.c arch/powerpc/platforms/cell/spufs/context.c drivers/android/binder.c drivers/gpu/drm/etnaviv/etnaviv_gem.c drivers/infiniband/core/umem.c drivers/infiniband/core/umem_odp.c drivers/infiniband/hw/mlx4/main.c drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/usnic/usnic_uiom.c drivers/iommu/amd_iommu_v2.c drivers/iommu/intel-svm.c drivers/lguest/lguest_user.c drivers/misc/cxl/fault.c drivers/misc/mic/scif/scif_rma.c drivers/oprofile/buffer_sync.c drivers/vfio/vfio_iommu_type1.c drivers/vhost/vhost.c drivers/xen/gntdev.c fs/proc/array.c fs/proc/base.c fs/proc/task_mmu.c include/linux/sched/mm.h kernel/cpuset.c kernel/events/core.c kernel/exit.c kernel/fork.c kernel/ptrace.c kernel/sys.c kernel/trace/trace_output.c kernel/tsacct.c mm/memcontrol.c mm/memory.c mm/mempolicy.c mm/migrate.c mm/mmu_notifier.c mm/nommu.c mm/util.c # mm_access(): fs/proc/base.c include/linux/sched/mm.h kernel/fork.c mm/process_vm_access.c # mm_release(): arch/arc/include/asm/mmu_context.h fs/exec.c include/linux/sched/mm.h include/uapi/linux/sched.h kernel/exit.c kernel/fork.c 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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. 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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to <linux/sched/hotplug.h>Ingo Molnar1-0/+1
We are going to split <linux/sched/hotplug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/hotplug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. 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>
2017-02-27mm: add new mmgrab() helperVegard Nossum1-1/+1
Apart from adding the helper function itself, the rest of the kernel is converted mechanically using: git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/' git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/' This is needed for a later patch that hooks into the helper, but might be a worthwhile cleanup on its own. (Michal Hocko provided most of the kerneldoc comment.) Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-02arm64: make use of for_each_node_by_type()Dmitry Torokhov1-2/+2
Instead of open-coding the loop, let's use canned macro. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-11arm64: split thread_info from task stackMark Rutland1-0/+2
This patch moves arm64's struct thread_info from the task stack into task_struct. This protects thread_info from corruption in the case of stack overflows, and makes its address harder to determine if stack addresses are leaked, making a number of attacks more difficult. Precise detection and handling of overflow is left for subsequent patches. Largely, this involves changing code to store the task_struct in sp_el0, and acquire the thread_info from the task struct. Core code now implements current_thread_info(), and as noted in <linux/sched.h> this relies on offsetof(task_struct, thread_info) == 0, enforced by core code. This change means that the 'tsk' register used in entry.S now points to a task_struct, rather than a thread_info as it used to. To make this clear, the TI_* field offsets are renamed to TSK_TI_*, with asm-offsets appropriately updated to account for the structural change. Userspace clobbers sp_el0, and we can no longer restore this from the stack. Instead, the current task is cached in a per-cpu variable that we can safely access from early assembly as interrupts are disabled (and we are thus not preemptible). Both secondary entry and idle are updated to stash the sp and task pointer separately. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: James Morse <james.morse@arm.com> Cc: Kees Cook <keescook@chromium.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-11arm64: make cpu number a percpu variableMark Rutland1-0/+5
In the absence of CONFIG_THREAD_INFO_IN_TASK, core code maintains thread_info::cpu, and low-level architecture code can access this to build raw_smp_processor_id(). With CONFIG_THREAD_INFO_IN_TASK, core code maintains task_struct::cpu, which for reasons of hte header soup is not accessible to low-level arch code. Instead, we can maintain a percpu variable containing the cpu number. For both the old and new implementation of raw_smp_processor_id(), we read a syreg into a GPR, add an offset, and load the result. As the offset is now larger, it may not be folded into the load, but otherwise the assembly shouldn't change much. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Cc: James Morse <james.morse@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-11arm64: smp: prepare for smp_processor_id() reworkMark Rutland1-3/+4
Subsequent patches will make smp_processor_id() use a percpu variable. This will make smp_processor_id() dependent on the percpu offset, and thus we cannot use smp_processor_id() to figure out what to initialise the offset to. Prepare for this by initialising the percpu offset based on current::cpu, which will work regardless of how smp_processor_id() is implemented. Also, make this relationship obvious by placing this code together at the start of secondary_start_kernel(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Laura Abbott <labbott@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-10-17arm64: kernel: numa: fix ACPI boot cpu numa node mappingLorenzo Pieralisi1-0/+1
Commit 7ba5f605f3a0 ("arm64/numa: remove the limitation that cpu0 must bind to node0") removed the numa cpu<->node mapping restriction whereby logical cpu 0 always corresponds to numa node 0; removing the restriction was correct, in that it does not really exist in practice but the commit only updated the early mapping of logical cpu 0 to its real numa node for the DT boot path, missing the ACPI one, leading to boot failures on ACPI systems owing to missing node<->cpu map for logical cpu 0. Fix the issue by updating the ACPI boot path with code that carries out the early cpu<->node mapping also for the boot cpu (ie cpu 0), mirroring what is currently done in the DT boot path. Fixes: 7ba5f605f3a0 ("arm64/numa: remove the limitation that cpu0 must bind to node0") Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: Laszlo Ersek <lersek@redhat.com> Reported-by: Laszlo Ersek <lersek@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Hanjun Guo <hanjun.guo@linaro.org> Cc: Andrew Jones <drjones@redhat.com> Cc: Zhen Lei <thunder.leizhen@huawei.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-10-03Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-1/+13
Pull arm64 updates from Will Deacon: "It's a bit all over the place this time with no "killer feature" to speak of. Support for mismatched cache line sizes should help people seeing whacky JIT failures on some SoCs, and the big.LITTLE perf updates have been a long time coming, but a lot of the changes here are cleanups. We stray outside arch/arm64 in a few areas: the arch/arm/ arch_timer workaround is acked by Russell, the DT/OF bits are acked by Rob, the arch_timer clocksource changes acked by Marc, CPU hotplug by tglx and jump_label by Peter (all CC'd). Summary: - Support for execute-only page permissions - Support for hibernate and DEBUG_PAGEALLOC - Support for heterogeneous systems with mismatches cache line sizes - Errata workarounds (A53 843419 update and QorIQ A-008585 timer bug) - arm64 PMU perf updates, including cpumasks for heterogeneous systems - Set UTS_MACHINE for building rpm packages - Yet another head.S tidy-up - Some cleanups and refactoring, particularly in the NUMA code - Lots of random, non-critical fixes across the board" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (100 commits) arm64: tlbflush.h: add __tlbi() macro arm64: Kconfig: remove SMP dependence for NUMA arm64: Kconfig: select OF/ACPI_NUMA under NUMA config arm64: fix dump_backtrace/unwind_frame with NULL tsk arm/arm64: arch_timer: Use archdata to indicate vdso suitability arm64: arch_timer: Work around QorIQ Erratum A-008585 arm64: arch_timer: Add device tree binding for A-008585 erratum arm64: Correctly bounds check virt_addr_valid arm64: migrate exception table users off module.h and onto extable.h arm64: pmu: Hoist pmu platform device name arm64: pmu: Probe default hw/cache counters arm64: pmu: add fallback probe table MAINTAINERS: Update ARM PMU PROFILING AND DEBUGGING entry arm64: Improve kprobes test for atomic sequence arm64/kvm: use alternative auto-nop arm64: use alternative auto-nop arm64: alternative: add auto-nop infrastructure arm64: lse: convert lse alternatives NOP padding to use __nops arm64: barriers: introduce nops and __nops macros for NOP sequences arm64: sysreg: replace open-coded mrs_s/msr_s with {read,write}_sysreg_s ...
2016-09-23arm64: Call numa_store_cpu_info() earlier.David Daney1-8/+6
The wq_numa_init() function makes a private CPU to node map by calling cpu_to_node() early in the boot process, before the non-boot CPUs are brought online. Since the default implementation of cpu_to_node() returns zero for CPUs that have never been brought online, the workqueue system's view is that *all* CPUs are on node zero. When the unbound workqueue for a non-zero node is created, the tsk_cpus_allowed() for the worker threads is the empty set because there are, in the view of the workqueue system, no CPUs on non-zero nodes. The code in try_to_wake_up() using this empty cpumask ends up using the cpumask empty set value of NR_CPUS as an index into the per-CPU area pointer array, and gets garbage as it is one past the end of the array. This results in: [ 0.881970] Unable to handle kernel paging request at virtual address fffffb1008b926a4 [ 1.970095] pgd = fffffc00094b0000 [ 1.973530] [fffffb1008b926a4] *pgd=0000000000000000, *pud=0000000000000000, *pmd=0000000000000000 [ 1.982610] Internal error: Oops: 96000004 [#1] SMP [ 1.987541] Modules linked in: [ 1.990631] CPU: 48 PID: 295 Comm: cpuhp/48 Tainted: G W 4.8.0-rc6-preempt-vol+ #9 [ 1.999435] Hardware name: Cavium ThunderX CN88XX board (DT) [ 2.005159] task: fffffe0fe89cc300 task.stack: fffffe0fe8b8c000 [ 2.011158] PC is at try_to_wake_up+0x194/0x34c [ 2.015737] LR is at try_to_wake_up+0x150/0x34c [ 2.020318] pc : [<fffffc00080e7468>] lr : [<fffffc00080e7424>] pstate: 600000c5 [ 2.027803] sp : fffffe0fe8b8fb10 [ 2.031149] x29: fffffe0fe8b8fb10 x28: 0000000000000000 [ 2.036522] x27: fffffc0008c63bc8 x26: 0000000000001000 [ 2.041896] x25: fffffc0008c63c80 x24: fffffc0008bfb200 [ 2.047270] x23: 00000000000000c0 x22: 0000000000000004 [ 2.052642] x21: fffffe0fe89d25bc x20: 0000000000001000 [ 2.058014] x19: fffffe0fe89d1d00 x18: 0000000000000000 [ 2.063386] x17: 0000000000000000 x16: 0000000000000000 [ 2.068760] x15: 0000000000000018 x14: 0000000000000000 [ 2.074133] x13: 0000000000000000 x12: 0000000000000000 [ 2.079505] x11: 0000000000000000 x10: 0000000000000000 [ 2.084879] x9 : 0000000000000000 x8 : 0000000000000000 [ 2.090251] x7 : 0000000000000040 x6 : 0000000000000000 [ 2.095621] x5 : ffffffffffffffff x4 : 0000000000000000 [ 2.100991] x3 : 0000000000000000 x2 : 0000000000000000 [ 2.106364] x1 : fffffc0008be4c24 x0 : ffffff0ffffada80 [ 2.111737] [ 2.113236] Process cpuhp/48 (pid: 295, stack limit = 0xfffffe0fe8b8c020) [ 2.120102] Stack: (0xfffffe0fe8b8fb10 to 0xfffffe0fe8b90000) [ 2.125914] fb00: fffffe0fe8b8fb80 fffffc00080e7648 . . . [ 2.442859] Call trace: [ 2.445327] Exception stack(0xfffffe0fe8b8f940 to 0xfffffe0fe8b8fa70) [ 2.451843] f940: fffffe0fe89d1d00 0000040000000000 fffffe0fe8b8fb10 fffffc00080e7468 [ 2.459767] f960: fffffe0fe8b8f980 fffffc00080e4958 ffffff0ff91ab200 fffffc00080e4b64 [ 2.467690] f980: fffffe0fe8b8f9d0 fffffc00080e515c fffffe0fe8b8fa80 0000000000000000 [ 2.475614] f9a0: fffffe0fe8b8f9d0 fffffc00080e58e4 fffffe0fe8b8fa80 0000000000000000 [ 2.483540] f9c0: fffffe0fe8d10000 0000000000000040 fffffe0fe8b8fa50 fffffc00080e5ac4 [ 2.491465] f9e0: ffffff0ffffada80 fffffc0008be4c24 0000000000000000 0000000000000000 [ 2.499387] fa00: 0000000000000000 ffffffffffffffff 0000000000000000 0000000000000040 [ 2.507309] fa20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 2.515233] fa40: 0000000000000000 0000000000000000 0000000000000000 0000000000000018 [ 2.523156] fa60: 0000000000000000 0000000000000000 [ 2.528089] [<fffffc00080e7468>] try_to_wake_up+0x194/0x34c [ 2.533723] [<fffffc00080e7648>] wake_up_process+0x28/0x34 [ 2.539275] [<fffffc00080d3764>] create_worker+0x110/0x19c [ 2.544824] [<fffffc00080d69dc>] alloc_unbound_pwq+0x3cc/0x4b0 [ 2.550724] [<fffffc00080d6bcc>] wq_update_unbound_numa+0x10c/0x1e4 [ 2.557066] [<fffffc00080d7d78>] workqueue_online_cpu+0x220/0x28c [ 2.563234] [<fffffc00080bd288>] cpuhp_invoke_callback+0x6c/0x168 [ 2.569398] [<fffffc00080bdf74>] cpuhp_up_callbacks+0x44/0xe4 [ 2.575210] [<fffffc00080be194>] cpuhp_thread_fun+0x13c/0x148 [ 2.581027] [<fffffc00080dfbac>] smpboot_thread_fn+0x19c/0x1a8 [ 2.586929] [<fffffc00080dbd64>] kthread+0xdc/0xf0 [ 2.591776] [<fffffc0008083380>] ret_from_fork+0x10/0x50 [ 2.597147] Code: b00057e1 91304021 91005021 b8626822 (b8606821) [ 2.603464] ---[ end trace 58c0cd36b88802bc ]--- [ 2.608138] Kernel panic - not syncing: Fatal exception Fix by moving call to numa_store_cpu_info() for all CPUs into smp_prepare_cpus(), which happens before wq_numa_init(). Since smp_store_cpu_info() now contains only a single function call, simplify by removing the function and out-lining its contents. Suggested-by: Robert Richter <rric@kernel.org> Fixes: 1a2db300348b ("arm64, numa: Add NUMA support for arm64 platforms.") Cc: <stable@vger.kernel.org> # 4.7.x- Signed-off-by: David Daney <david.daney@cavium.com> Reviewed-by: Robert Richter <rrichter@cavium.com> Tested-by: Yisheng Xie <xieyisheng1@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-09-09arm64: Rearrange CPU errata workaround checksSuzuki K Poulose1-1/+7
Right now we run through the work around checks on a CPU from __cpuinfo_store_cpu. There are some problems with that: 1) We initialise the system wide CPU feature registers only after the Boot CPU updates its cpuinfo. Now, if a work around depends on the variance of a CPU ID feature (e.g, check for Cache Line size mismatch), we have no way of performing it cleanly for the boot CPU. 2) It is out of place, invoked from __cpuinfo_store_cpu() in cpuinfo.c. It is not an obvious place for that. This patch rearranges the CPU specific capability(aka work around) checks. 1) At the moment we use verify_local_cpu_capabilities() to check if a new CPU has all the system advertised features. Use this for the secondary CPUs to perform the work around check. For that we rename verify_local_cpu_capabilities() => check_local_cpu_capabilities() which: If the system wide capabilities haven't been initialised (i.e, the CPU is activated at the boot), update the system wide detected work arounds. Otherwise (i.e a CPU hotplugged in later) verify that this CPU conforms to the system wide capabilities. 2) Boot CPU updates the work arounds from smp_prepare_boot_cpu() after we have initialised the system wide CPU feature values. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09arm64/numa: remove the limitation that cpu0 must bind to node0Zhen Lei1-0/+1
1. Remove the old binding code. 2. Read the nid of cpu0 from dts. 3. Fallback the nid of cpu0 to 0 when numa=off is set in bootargs. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-07arm64: Use static keys for CPU featuresCatalin Marinas1-0/+5
This patch adds static keys transparently for all the cpu_hwcaps features by implementing an array of default-false static keys and enabling them when detected. The cpus_have_cap() check uses the static keys if the feature being checked is a constant, otherwise the compiler generates the bitmap test. Because of the early call to static_branch_enable() via check_local_cpu_errata() -> update_cpu_capabilities(), the jump labels are initialised in cpuinfo_store_boot_cpu(). Cc: Will Deacon <will.deacon@arm.com> Cc: Suzuki K. Poulose <Suzuki.Poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-09arm64: Support hard limit of cpu count by nr_cpusKefeng Wang1-4/+4
Enable the hard limit of cpu count by set boot options nr_cpus=x on arm64, and make a minor change about message when total number of cpu exceeds the limit. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reported-by: Shiyuan Hu <hushiyuan@huawei.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-27Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-2/+8
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 ...
2016-07-25Merge branch 'acpi-numa'Rafael J. Wysocki1-0/+2
* 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
2016-07-21arm64: Honor nosmp kernel command line optionSuzuki K Poulose1-0/+7
Passing "nosmp" should boot the kernel with a single processor, without provision to enable secondary CPUs even if they are present. "nosmp" is implemented by setting maxcpus=0. At the moment we still mark the secondary CPUs present even with nosmp, which allows the userspace to bring them up. This patch corrects the smp_prepare_cpus() to honor the maxcpus == 0. Commit 44dbcc93ab67145 ("arm64: Fix behavior of maxcpus=N") fixed the behavior for maxcpus >= 1, but broke maxcpus = 0. Fixes: 44dbcc93ab67 ("arm64: Fix behavior of maxcpus=N") Cc: <stable@vger.kernel.org> # 4.7+ Cc: Will Deacon <will.deacon@arm.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> [catalin.marinas@arm.com: updated code comment] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-21arm64: Fix incorrect per-cpu usage for boot CPUSuzuki K Poulose1-1/+1
In smp_prepare_boot_cpu(), we invoke cpuinfo_store_boot_cpu to store the cpuinfo in a per-cpu ptr, before initialising the per-cpu offset for the boot CPU. This patch reorders the sequence to make sure we initialise the per-cpu offset before accessing the per-cpu area. Commit 4b998ff1885eec ("arm64: Delay cpuinfo_store_boot_cpu") fixed the issue where we modified the per-cpu area even before the kernel initialises the per-cpu areas, but failed to wait until the boot cpu updated it's offset. Fixes: 4b998ff1885e ("arm64: Delay cpuinfo_store_boot_cpu") Cc: <stable@vger.kernel.org> # 4.4+ Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19arm64: debug: unmask PSTATE.D earlierWill Deacon1-1/+0
Clearing PSTATE.D is one of the requirements for generating a debug exception. The arm64 booting protocol requires that PSTATE.D is set, since many of the debug registers (for example, the hw_breakpoint registers) are UNKNOWN out of reset and could potentially generate spurious, fatal debug exceptions in early boot code if PSTATE.D was clear. Once the debug registers have been safely initialised, PSTATE.D is cleared, however this is currently broken for two reasons: (1) The boot CPU clears PSTATE.D in a postcore_initcall and secondary CPUs clear PSTATE.D in secondary_start_kernel. Since the initcall runs after SMP (and the scheduler) have been initialised, there is no guarantee that it is actually running on the boot CPU. In this case, the boot CPU is left with PSTATE.D set and is not capable of generating debug exceptions. (2) In a preemptible kernel, we may explicitly schedule on the IRQ return path to EL1. If an IRQ occurs with PSTATE.D set in the idle thread, then we may schedule the kthread_init thread, run the postcore_initcall to clear PSTATE.D and then context switch back to the idle thread before returning from the IRQ. The exception return path will then restore PSTATE.D from the stack, and set it again. This patch fixes the problem by moving the clearing of PSTATE.D earlier to proc.S. This has the desirable effect of clearing it in one place for all CPUs, long before we have to worry about the scheduler or any exception handling. We ensure that the previous reset of MDSCR_EL1 has completed before unmasking the exception, so that any spurious exceptions resulting from UNKNOWN debug registers are not generated. Without this patch applied, the kprobes selftests have been seen to fail under KVM, where we end up attempting to step the OOL instruction buffer with PSTATE.D set and therefore fail to complete the step. Cc: <stable@vger.kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-27arm64: smp: Add function to determine if cpus are stuck in the kernelJames Morse1-0/+18
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 44dbcc93ab67 ("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>
2016-06-22arm64: smp: Add function to determine if cpus are stuck in the kernelJames Morse1-0/+18
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 44dbcc93ab67 ("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>
2016-05-30arm64, ACPI, NUMA: NUMA support based on SRAT and SLITHanjun Guo1-0/+2
Introduce a new file to hold ACPI based NUMA information parsing from SRAT and SLIT. SRAT includes the CPU ACPI ID to Proximity Domain mappings and memory ranges to Proximity Domain mapping. SLIT has the information of inter node distances(relative number for access latency). Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> [rrichter@cavium.com Reworked for numa v10 series ] Signed-off-by: Robert Richter <rrichter@cavium.com> [david.daney@cavium.com reorderd and combinded with other patches in Hanjun Guo's original set, removed get_mpidr_in_madt() and use acpi_map_madt_entry() instead.] Signed-off-by: David Daney <david.daney@cavium.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Dennis Chen <dennis.chen@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-05-11arm64: secondary_start_kernel: Remove unnecessary barrierSuzuki K Poulose1-2/+0
Remove the unnecessary smp_wmb(), which was added to make sure that the update_cpu_boot_status() completes before we mark the CPU online. But update_cpu_boot_status() already has dsb() (required for the failing CPUs) to ensure the correct behavior. Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Dennis Chen <dennis.chen@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-25arm64: Fix behavior of maxcpus=NSuzuki K Poulose1-17/+1
maxcpu=n sets the number of CPUs activated at boot time to a max of n, but allowing the remaining CPUs to be brought up later if the user decides to do so. However, on arm64 due to various reasons, we disallowed hotplugging CPUs beyond n, by marking them not present. Now that we have checks in place to make sure the hotplugged CPUs have compatible features with system and requires no new errata, relax the restriction. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-19arm64: Reduce verbosity on SMP CPU stopJan Glauber1-11/+5
When CPUs are stopped during an abnormal operation like panic for each CPU a line is printed and the stack trace is dumped. This information is only interesting for the aborting CPU and on systems with many CPUs it only makes it harder to debug if after the aborting CPU the log is flooded with data about all other CPUs too. Therefore remove the stack dump and printk of other CPUs and only print a single line that the other CPUs are going to be stopped and, in case any CPUs remain online list them. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-15arm64, numa: Add NUMA support for arm64 platforms.Ganapatrao Kulkarni1-0/+4
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: vhe: Verify CPU Exception LevelsSuzuki K Poulose1-0/+38
With a VHE capable CPU, kernel can run at EL2 and is a decided at early boot. If some of the CPUs didn't start it EL2 or doesn't have VHE, we could have CPUs running at different exception levels, all in the same kernel! This patch adds an early check for the secondary CPUs to detect such situations. For each non-boot CPU add a sanity check to make sure we don't have different run levels w.r.t the boot CPU. We save the information on whether the boot CPU is running in hyp mode or not and ensure the remaining CPUs match it. Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> [will: made boot_cpu_hyp_mode static] Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-17Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxLinus Torvalds1-3/+96
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 ...
2016-03-01arch/hotplug: Call into idle with a proper stateThomas Gleixner1-1/+1
Let the non boot cpus call into idle with the corresponding hotplug state, so the hotplug core can handle the further bringup. That's a first step to convert the boot side of the hotplugged cpus to do all the synchronization with the other side through the state machine. For now it'll only start the hotplug thread and kick the full bringup of the cpu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Rik van Riel <riel@redhat.com> Cc: Rafael Wysocki <rafael.j.wysocki@intel.com> Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25arm64: Handle early CPU boot failuresSuzuki K Poulose1-0/+45
A secondary CPU could fail to come online due to insufficient capabilities and could simply die or loop in the kernel. e.g, a CPU with no support for the selected kernel PAGE_SIZE loops in kernel with MMU turned off. or a hotplugged CPU which doesn't have one of the advertised system capability will die during the activation. There is no way to synchronise the status of the failing CPU back to the master. This patch solves the issue by adding a field to the secondary_data which can be updated by the failing CPU. If the secondary CPU fails even before turning the MMU on, it updates the status in a special variable reserved in the head.txt section to make sure that the update can be cache invalidated safely without possible sharing of cache write back granule. Here are the possible states : -1. CPU_MMU_OFF - Initial value set by the master CPU, this value indicates that the CPU could not turn the MMU on, hence the status could not be reliably updated in the secondary_data. Instead, the CPU has updated the status @ __early_cpu_boot_status. 0. CPU_BOOT_SUCCESS - CPU has booted successfully. 1. CPU_KILL_ME - CPU has invoked cpu_ops->die, indicating the master CPU to synchronise by issuing a cpu_ops->cpu_kill. 2. CPU_STUCK_IN_KERNEL - CPU couldn't invoke die(), instead is looping in the kernel. This information could be used by say, kexec to check if it is really safe to do a kexec reboot. 3. CPU_PANIC_KERNEL - CPU detected some serious issues which requires kernel to crash immediately. The secondary CPU cannot call panic() until it has initialised the GIC. This flag can be used to instruct the master to do so. Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> [catalin.marinas@arm.com: conflict resolution] [catalin.marinas@arm.com: converted "status" from int to long] [catalin.marinas@arm.com: updated update_early_cpu_boot_status to use str_l] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24arm64: Move cpu_die_early to smp.cSuzuki K Poulose1-0/+22
This patch moves cpu_die_early to smp.c, where it fits better. No functional changes, except for adding the necessary checks for CONFIG_HOTPLUG_CPU. Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16arm64: kernel: implement ACPI parking protocolLorenzo Pieralisi1-0/+28
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.docx Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: Loc 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: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16arm64: unify idmap removalMark Rutland1-3/+1
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>
2015-11-12arm64: smp: make of_parse_and_init_cpus staticJisheng Zhang1-1/+1
of_parse_and_init_cpus is only called from within smp.c, so it can be declared static. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Delay cpu feature capability checksSuzuki K. Poulose1-0/+7
At the moment we run through the arm64_features capability list for each CPU and set the capability if one of the CPU supports it. This could be problematic in a heterogeneous system with differing capabilities. Delay the CPU feature checks until all the enabled CPUs are up(i.e, smp_cpus_done(), so that we can make better decisions based on the overall system capability. Once we decide and advertise the capabilities the alternatives can be applied. From this state, we cannot roll back a feature to disabled based on the values from a new hotplugged CPU, due to the runtime patching and other reasons. So, for all new CPUs, we need to make sure that they have the established system capabilities. Failing which, we bring the CPU down, preventing it from turning online. Once the capabilities are decided, any new CPU booting up goes through verification to ensure that it has all the enabled capabilities and also invokes the respective enable() method on the CPU. The CPU errata checks are not delayed and is still executed per-CPU to detect the respective capabilities. If we ever come across a non-errata capability that needs to be checked on each-CPU, we could introduce them via a new capability table(or introduce a flag), which can be processed per CPU. The next patch will make the feature checks use the system wide safe value of a feature register. NOTE: The enable() methods associated with the capability is scheduled on all the CPUs (which is the only use case at the moment). If we need a different type of 'enable()' which only needs to be run once on any CPU, we should be able to handle that when needed. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> [catalin.marinas@arm.com: static variable and coding style fixes] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Delay cpuinfo_store_boot_cpuSuzuki K. Poulose1-0/+1
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. Poulose1-0/+1
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. Poulose1-1/+2
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>