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2020-01-19KVM: arm/arm64: Correct CPSR on exception entryMark Rutland
When KVM injects an exception into a guest, it generates the CPSR value from scratch, configuring CPSR.{M,A,I,T,E}, and setting all other bits to zero. This isn't correct, as the architecture specifies that some CPSR bits are (conditionally) cleared or set upon an exception, and others are unchanged from the original context. This patch adds logic to match the architectural behaviour. To make this simple to follow/audit/extend, documentation references are provided, and bits are configured in order of their layout in SPSR_EL2. This layout can be seen in the diagram on ARM DDI 0487E.a page C5-426. Note that this code is used by both arm and arm64, and is intended to fuction with the SPSR_EL2 and SPSR_HYP layouts. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200108134324.46500-3-mark.rutland@arm.com
2019-08-07arm64: Add support for function error injectionLeo Yan
Inspired by the commit 7cd01b08d35f ("powerpc: Add support for function error injection"), this patch supports function error injection for Arm64. This patch mainly support two functions: one is regs_set_return_value() which is used to overwrite the return value; the another function is override_function_with_return() which is to override the probed function returning and jump to its caller. Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Leo Yan <leo.yan@linaro.org> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-01arm64: Lower priority mask for GIC_PRIO_IRQONJulien Thierry
On a system with two security states, if SCR_EL3.FIQ is cleared, non-secure IRQ priorities get shifted to fit the secure view but priority masks aren't. On such system, it turns out that GIC_PRIO_IRQON masks the priority of normal interrupts, which obviously ends up in a hang. Increase GIC_PRIO_IRQON value (i.e. lower priority) to make sure interrupts are not blocked by it. Cc: Oleg Nesterov <oleg@redhat.com> Fixes: bd82d4bd21880b7c ("arm64: Fix incorrect irqflag restore for priority masking") Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Julien Thierry <julien.thierry.kdev@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [will: fixed Fixes: tag] Signed-off-by: Will Deacon <will@kernel.org>
2019-07-12Merge tag 'asm-generic-5.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "The asm-generic changes for 5.3 consist of a cleanup series to remove ptrace.h from Christoph Hellwig, who explains: 'asm-generic/ptrace.h is a little weird in that it doesn't actually implement any functionality, but it provided multiple layers of macros that just implement trivial inline functions. We implement those directly in the few architectures and be off with a much simpler design.' at https://lore.kernel.org/lkml/20190624054728.30966-1-hch@lst.de/" * tag 'asm-generic-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: remove ptrace.h x86: don't use asm-generic/ptrace.h sh: don't use asm-generic/ptrace.h powerpc: don't use asm-generic/ptrace.h arm64: don't use asm-generic/ptrace.h
2019-07-08Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP} - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to manage the permissions of executable vmalloc regions more strictly - Slight performance improvement by keeping softirqs enabled while touching the FPSIMD/SVE state (kernel_neon_begin/end) - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new XAFLAG and AXFLAG instructions for floating point comparison flags manipulation) and FRINT (rounding floating point numbers to integers) - Re-instate ARM64_PSEUDO_NMI support which was previously marked as BROKEN due to some bugs (now fixed) - Improve parking of stopped CPUs and implement an arm64-specific panic_smp_self_stop() to avoid warning on not being able to stop secondary CPUs during panic - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI platforms - perf: DDR performance monitor support for iMX8QXP - cache_line_size() can now be set from DT or ACPI/PPTT if provided to cope with a system cache info not exposed via the CPUID registers - Avoid warning on hardware cache line size greater than ARCH_DMA_MINALIGN if the system is fully coherent - arm64 do_page_fault() and hugetlb cleanups - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep) - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the 'arm_boot_flags' introduced in 5.1) - CONFIG_RANDOMIZE_BASE now enabled in defconfig - Allow the selection of ARM64_MODULE_PLTS, currently only done via RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill over into the vmalloc area - Make ZONE_DMA32 configurable * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits) perf: arm_spe: Enable ACPI/Platform automatic module loading arm_pmu: acpi: spe: Add initial MADT/SPE probing ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens ACPI/PPTT: Modify node flag detection to find last IDENTICAL x86/entry: Simplify _TIF_SYSCALL_EMU handling arm64: rename dump_instr as dump_kernel_instr arm64/mm: Drop [PTE|PMD]_TYPE_FAULT arm64: Implement panic_smp_self_stop() arm64: Improve parking of stopped CPUs arm64: Expose FRINT capabilities to userspace arm64: Expose ARMv8.5 CondM capability to userspace arm64: defconfig: enable CONFIG_RANDOMIZE_BASE arm64: ARM64_MODULES_PLTS must depend on MODULES arm64: bpf: do not allocate executable memory arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP arm64: module: create module allocations without exec permissions arm64: Allow user selection of ARM64_MODULE_PLTS acpi/arm64: ignore 5.1 FADTs that are reported as 5.0 arm64: Allow selecting Pseudo-NMI again ...
2019-07-01arm64: don't use asm-generic/ptrace.hChristoph Hellwig
Doing the indirection through macros for the regs accessors just makes them harder to read, so implement the helpers directly. Note that only the helpers actually used are implemented now. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-06-21arm64: Fix incorrect irqflag restore for priority maskingJulien Thierry
When using IRQ priority masking to disable interrupts, in order to deal with the PSR.I state, local_irq_save() would convert the I bit into a PMR value (GIC_PRIO_IRQOFF). This resulted in local_irq_restore() potentially modifying the value of PMR in undesired location due to the state of PSR.I upon flag saving [1]. In an attempt to solve this issue in a less hackish manner, introduce a bit (GIC_PRIO_IGNORE_PMR) for the PMR values that can represent whether PSR.I is being used to disable interrupts, in which case it takes precedence of the status of interrupt masking via PMR. GIC_PRIO_PSR_I_SET is chosen such that (<pmr_value> | GIC_PRIO_PSR_I_SET) does not mask more interrupts than <pmr_value> as some sections (e.g. arch_cpu_idle(), interrupt acknowledge path) requires PMR not to mask interrupts that could be signaled to the CPU when using only PSR.I. [1] https://www.spinics.net/lists/arm-kernel/msg716956.html Fixes: 4a503217ce37 ("arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking") Cc: <stable@vger.kernel.org> # 5.1.x- Reported-by: Zenghui Yu <yuzenghui@huawei.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Wei Li <liwei391@huawei.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Christoffer Dall <christoffer.dall@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Suzuki K Pouloze <suzuki.poulose@arm.com> Cc: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-12arm64: ptrace: Add function argument access APIMasami Hiramatsu
Add regs_get_argument() which returns N th argument of the function call. On arm64, it supports up to 8th argument. Note that this chooses most probably assignment, in some case it can be incorrect (e.g. passing data structure or floating point etc.) This enables ftrace kprobe events to access kernel function arguments via $argN syntax. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> [will: tidied up the comment a bit] Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-02-06arm64: Make PMR part of task contextJulien Thierry
In order to replace PSR.I interrupt disabling/enabling with ICC_PMR_EL1 interrupt masking, ICC_PMR_EL1 needs to be saved/restored when taking/returning from an exception. This mimics the way hardware saves and restores PSR.I bit in spsr_el1 for exceptions and ERET. Add PMR to the registers to save in the pt_regs struct upon kernel entry, and restore it before ERET. Also, initialize it to a sane value when creating new tasks. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-02-06arm64: ptrace: Provide definitions for PMR valuesJulien Thierry
Introduce fixed values for PMR that are going to be used to mask and unmask interrupts by priority. The current priority given to GIC interrupts is 0xa0, so clearing PMR's most significant bit is enough to mask interrupts. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Suggested-by: Daniel Thompson <daniel.thompson@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-10-25Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Radim Krčmář: "ARM: - Improved guest IPA space support (32 to 52 bits) - RAS event delivery for 32bit - PMU fixes - Guest entry hardening - Various cleanups - Port of dirty_log_test selftest PPC: - Nested HV KVM support for radix guests on POWER9. The performance is much better than with PR KVM. Migration and arbitrary level of nesting is supported. - Disable nested HV-KVM on early POWER9 chips that need a particular hardware bug workaround - One VM per core mode to prevent potential data leaks - PCI pass-through optimization - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base s390: - Initial version of AP crypto virtualization via vfio-mdev - Improvement for vfio-ap - Set the host program identifier - Optimize page table locking x86: - Enable nested virtualization by default - Implement Hyper-V IPI hypercalls - Improve #PF and #DB handling - Allow guests to use Enlightened VMCS - Add migration selftests for VMCS and Enlightened VMCS - Allow coalesced PIO accesses - Add an option to perform nested VMCS host state consistency check through hardware - Automatic tuning of lapic_timer_advance_ns - Many fixes, minor improvements, and cleanups" * tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned Revert "kvm: x86: optimize dr6 restore" KVM: PPC: Optimize clearing TCEs for sparse tables x86/kvm/nVMX: tweak shadow fields selftests/kvm: add missing executables to .gitignore KVM: arm64: Safety check PSTATE when entering guest and handle IL KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips arm/arm64: KVM: Enable 32 bits kvm vcpu events support arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension() KVM: arm64: Fix caching of host MDCR_EL2 value KVM: VMX: enable nested virtualization by default KVM/x86: Use 32bit xor to clear registers in svm.c kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD kvm: vmx: Defer setting of DR6 until #DB delivery kvm: x86: Defer setting of CR2 until #PF delivery kvm: x86: Add payload operands to kvm_multiple_exception kvm: x86: Add exception payload fields to kvm_vcpu_events kvm: x86: Add has_payload and payload to kvm_queued_exception KVM: Documentation: Fix omission in struct kvm_vcpu_events KVM: selftests: add Enlightened VMCS test ...
2018-10-19KVM: arm64: Safety check PSTATE when entering guest and handle ILChristoffer Dall
This commit adds a paranoid check when entering the guest to make sure we don't attempt running guest code in an equally or more privilged mode than the hypervisor. We also catch other accidental programming of the SPSR_EL2 which results in an illegal exception return and report this safely back to the user. Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-14arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3Will Deacon
On CPUs with support for PSTATE.SSBS, the kernel can toggle the SSBD state without needing to call into firmware. This patch hooks into the existing SSBD infrastructure so that SSBS is used on CPUs that support it, but it's all made horribly complicated by the very real possibility of big/little systems that don't uniformly provide the new capability. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-07-05arm64: remove unused COMPAT_PSR definitionsMark Rutland
Now that users have been migrated to PSR_AA32, kill the unused COMPAT_PSR definitions. The only difference we need a definition for is COMPAT_PSR_DIT_BIT, which differs from PSR_AA32_DIT_BIT. Signed-off-by: Mark Rutland <mark.rutland@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>
2018-07-05arm64: use PSR_AA32 definitionsMark Rutland
Some code cares about the SPSR_ELx format for exceptions taken from AArch32 to inspect or manipulate the SPSR_ELx value, which is already in the SPSR_ELx format, and not in the AArch32 PSR format. To separate these from cases where we care about the AArch32 PSR format, migrate these cases to use the PSR_AA32_* definitions rather than COMPAT_PSR_*. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@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>
2018-07-05arm64: add PSR_AA32_* definitionsMark Rutland
The AArch32 CPSR/SPSR format is *almost* identical to the AArch64 SPSR_ELx format for exceptions taken from AArch32, but the two have diverged with the addition of DIT, and we need to treat the two as logically distinct. This patch adds new definitions for the SPSR_ELx format for exceptions taken from AArch32, with a consistent PSR_AA32_ prefix. The existing COMPAT_PSR_ definitions will be used for the PSR format as seen from AArch32. Definitions of DIT are provided for both, and inline functions are provided to map between the two formats. Note that for SPSR_ELx, the (RES0) J bit has been re-allocated as the DIT bit. Once users of the COMPAT_PSR definitions have been migrated over to the PSR_AA32 definitions, the (majority of) the former will be removed, so no efforts is made to avoid duplication until then. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoffer Dall <christoffer.dall@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Suzuki Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-09Merge branch 'arm64/exception-stack' of ↵Catalin Marinas
git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core * 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux: arm64: unwind: remove sp from struct stackframe arm64: unwind: reference pt_regs via embedded stack frame arm64: unwind: disregard frame.sp when validating frame pointer arm64: unwind: avoid percpu indirection for irq stack arm64: move non-entry code out of .entry.text arm64: consistently use bl for C exception entry arm64: Add ASM_BUG()
2017-08-09arm64: unwind: reference pt_regs via embedded stack frameArd Biesheuvel
As it turns out, the unwind code is slightly broken, and probably has been for a while. The problem is in the dumping of the exception stack, which is intended to dump the contents of the pt_regs struct at each level in the call stack where an exception was taken and routed to a routine marked as __exception (which means its stack frame is right below the pt_regs struct on the stack). 'Right below the pt_regs struct' is ill defined, though: the unwind code assigns 'frame pointer + 0x10' to the .sp member of the stackframe struct at each level, and dump_backtrace() happily dereferences that as the pt_regs pointer when encountering an __exception routine. However, the actual size of the stack frame created by this routine (which could be one of many __exception routines we have in the kernel) is not known, and so frame.sp is pretty useless to figure out where struct pt_regs really is. So it seems the only way to ensure that we can find our struct pt_regs when walking the stack frames is to put it at a known fixed offset of the stack frame pointer that is passed to such __exception routines. The simplest way to do that is to put it inside pt_regs itself, which is the main change implemented by this patch. As a bonus, doing this allows us to get rid of a fair amount of cruft related to walking from one stack to the other, which is especially nice since we intend to introduce yet another stack for overflow handling once we add support for vmapped stacks. It also fixes an inconsistency where we only add a stack frame pointing to ELR_EL1 if we are executing from the IRQ stack but not when we are executing from the task stack. To consistly identify exceptions regs even in the presence of exceptions taken from entry code, we must check whether the next frame was created by entry text, rather than whether the current frame was crated by exception text. To avoid backtracing using PCs that fall in the idmap, or are controlled by userspace, we must explcitly zero the FP and LR in startup paths, and must ensure that the frame embedded in pt_regs is zeroed upon entry from EL0. To avoid these NULL entries showin in the backtrace, unwind_frame() is updated to avoid them. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [Mark: compare current frame against .entry.text, avoid bogus PCs] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will.deacon@arm.com>
2017-08-07arm64: Abstract syscallno manipulationDave Martin
The -1 "no syscall" value is written in various ways, shared with the user ABI in some places, and generally obscure. This patch attempts to make things a little more consistent and readable by replacing all these uses with a single #define. A couple of symbolic helpers are provided to clarify the intent further. Because the in-syscall check in do_signal() is changed from >= 0 to != NO_SYSCALL by this patch, different behaviour may be observable if syscallno is set to values less than -1 by a tracer. However, this is not different from the behaviour that is already observable if a tracer sets syscallno to a value >= __NR_(compat_)syscalls. It appears that this can cause spurious syscall restarting, but that is not a new behaviour either, and does not appear harmful. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-07arm64: syscallno is secretly an int, make it officialDave Martin
The upper 32 bits of the syscallno field in thread_struct are handled inconsistently, being sometimes zero extended and sometimes sign-extended. In fact, only the lower 32 bits seem to have any real significance for the behaviour of the code: it's been OK to handle the upper bits inconsistently because they don't matter. Currently, the only place I can find where those bits are significant is in calling trace_sys_enter(), which may be unintentional: for example, if a compat tracer attempts to cancel a syscall by passing -1 to (COMPAT_)PTRACE_SET_SYSCALL at the syscall-enter-stop, it will be traced as syscall 4294967295 rather than -1 as might be expected (and as occurs for a native tracer doing the same thing). Elsewhere, reads of syscallno cast it to an int or truncate it. There's also a conspicuous amount of code and casting to bodge around the fact that although semantically an int, syscallno is stored as a u64. Let's not pretend any more. In order to preserve the stp x instruction that stores the syscall number in entry.S, this patch special-cases the layout of struct pt_regs for big endian so that the newly 32-bit syscallno field maps onto the low bits of the stored value. This is not beautiful, but benchmarking of the getpid syscall on Juno suggests indicates a minor slowdown if the stp is split into an stp x and stp w. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-02-15arm64: ptrace: add XZR-safe regs accessorsMark Rutland
In A64, XZR and the SP share the same encoding (31), and whether an instruction accesses XZR or SP for a particular register parameter depends on the definition of the instruction. We store the SP in pt_regs::regs[31], and thus when emulating instructions, we must be careful to not erroneously read from or write back to the saved SP. Unfortunately, we often fail to be this careful. In all cases, instructions using a transfer register parameter Xt use this to refer to XZR rather than SP. This patch adds helpers so that we can more easily and consistently handle these cases. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-07arm64: Add uprobe supportPratyush Anand
This patch adds support for uprobe on ARM64 architecture. Unit tests for following have been done so far and they have been found working 1. Step-able instructions, like sub, ldr, add etc. 2. Simulation-able like ret, cbnz, cbz etc. 3. uretprobe 4. Reject-able instructions like sev, wfe etc. 5. trapped and abort xol path 6. probe at unaligned user address. 7. longjump test cases Currently it does not support aarch32 instruction probing. Signed-off-by: Pratyush Anand <panand@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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 ...
2016-07-27arm64: arm: Fix-up the removal of the arm64 regs_query_register_name() prototypeCatalin Marinas
Commit 0a8ea52c3eb1 ("arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature") inadvertently removed the arch/arm prototype instead of the arm64 one introduced by the original patch. There should not be any bisection issues since this function is not called from anywhere else (it could as well be removed from arch/arm at some point). Fixes: 0a8ea52c3eb1 ("arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature") Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-21Merge branch 'for-next/kprobes' into for-next/coreCatalin Marinas
* kprobes: arm64: kprobes: Add KASAN instrumentation around stack accesses arm64: kprobes: Cleanup jprobe_return arm64: kprobes: Fix overflow when saving stack arm64: kprobes: WARN if attempting to step with PSTATE.D=1 kprobes: Add arm64 case in kprobe example module arm64: Add kernel return probes support (kretprobes) arm64: Add trampoline code for kretprobes arm64: kprobes instruction simulation support arm64: Treat all entry code as non-kprobe-able arm64: Blacklist non-kprobe-able symbol arm64: Kprobes with single stepping support arm64: add conditional instruction simulation support arm64: Add more test functions to insn.c arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature
2016-07-19arm64: ptrace: remove extra define for CPSR's E bitVladimir Murzin
...and do not confuse source navigation tools ;) Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19arm64: Kprobes with single stepping supportSandeepa Prabhu
Add support for basic kernel probes(kprobes) and jump probes (jprobes) for ARM64. Kprobes utilizes software breakpoint and single step debug exceptions supported on ARM v8. A software breakpoint is placed at the probe address to trap the kernel execution into the kprobe handler. ARM v8 supports enabling single stepping before the break exception return (ERET), with next PC in exception return address (ELR_EL1). The kprobe handler prepares an executable memory slot for out-of-line execution with a copy of the original instruction being probed, and enables single stepping. The PC is set to the out-of-line slot address before the ERET. With this scheme, the instruction is executed with the exact same register context except for the PC (and DAIF) registers. Debug mask (PSTATE.D) is enabled only when single stepping a recursive kprobe, e.g.: during kprobes reenter so that probed instruction can be single stepped within the kprobe handler -exception- context. The recursion depth of kprobe is always 2, i.e. upon probe re-entry, any further re-entry is prevented by not calling handlers and the case counted as a missed kprobe). Single stepping from the x-o-l slot has a drawback for PC-relative accesses like branching and symbolic literals access as the offset from the new PC (slot address) may not be ensured to fit in the immediate value of the opcode. Such instructions need simulation, so reject probing them. Instructions generating exceptions or cpu mode change are rejected for probing. Exclusive load/store instructions are rejected too. Additionally, the code is checked to see if it is inside an exclusive load/store sequence (code from Pratyush). System instructions are mostly enabled for stepping, except MSR/MRS accesses to "DAIF" flags in PSTATE, which are not safe for probing. This also changes arch/arm64/include/asm/ptrace.h to use include/asm-generic/ptrace.h. Thanks to Steve Capper and Pratyush Anand for several suggested Changes. Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com> Signed-off-by: David A. Long <dave.long@linaro.org> Signed-off-by: Pratyush Anand <panand@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19arm64: Add HAVE_REGS_AND_STACK_ACCESS_API featureDavid A. Long
Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64, including supporting functions and defines. Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> [catalin.marinas@arm.com: Remove unused functions] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-07arm64: kernel: Save and restore UAO and addr_limit on exception entryJames Morse
If we take an exception while at EL1, the exception handler inherits the original context's addr_limit and PSTATE.UAO values. To be consistent always reset addr_limit and PSTATE.UAO on (re-)entry to EL1. This prevents accidental re-use of the original context's addr_limit. Based on a similar patch for arm from Russell King. Cc: <stable@vger.kernel.org> # 4.6- Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-02arm64: Rework valid_user_regsMark Rutland
We validate pstate using PSR_MODE32_BIT, which is part of the user-provided pstate (and cannot be trusted). Also, we conflate validation of AArch32 and AArch64 pstate values, making the code difficult to reason about. Instead, validate the pstate value based on the associated task. The task may or may not be current (e.g. when using ptrace), so this must be passed explicitly by callers. To avoid circular header dependencies via sched.h, is_compat_task is pulled out of asm/ptrace.h. To make the code possible to reason about, the AArch64 and AArch32 validation is split into separate functions. Software must respect the RES0 policy for SPSR bits, and thus the kernel mirrors the hardware policy (RAZ/WI) for bits as-yet unallocated. When these acquire an architected meaning writes may be permitted (potentially with additional validation). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Dave Martin <dave.martin@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-29arm64: Fix compat register mappingsRobin Murphy
For reasons not entirely apparent, but now enshrined in history, the architectural mapping of AArch32 banked registers to AArch64 registers actually orders SP_<mode> and LR_<mode> backwards compared to the intuitive r13/r14 order, for all modes except FIQ. Fix the compat_<reg>_<mode> macros accordingly, in the hope of avoiding subtle bugs with KVM and AArch32 guests. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-27arm64: force CONFIG_SMP=y and remove redundant #ifdefsWill Deacon
Nobody seems to be producing !SMP systems anymore, so this is just becoming a source of kernel bugs, particularly if people want to use coherent DMA with non-shared pages. This patch forces CONFIG_SMP=y for arm64, removing a modest amount of code in the process. Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-23arm64: Emulate SETEND for AArch32 tasksSuzuki K. Poulose
Emulate deprecated 'setend' instruction for AArch32 bit tasks. setend [le/be] - Sets the endianness of EL0 On systems with CPUs which support mixed endian at EL0, the hardware support for the instruction can be enabled by setting the SCTLR_EL1.SED bit. Like the other emulated instructions it is controlled by an entry in /proc/sys/abi/. For more information see : Documentation/arm64/legacy_instructions.txt The instruction is emulated by setting/clearing the SPSR_EL1.E bit, which will be reflected in the PSTATE.E in AArch32 context. This patch also restores the native endianness for the execution of signal handlers, since the process could have changed the endianness. Note: All CPUs on the system must have mixed endian support at EL0. Once the handler is registered, hotplugging a CPU which doesn't support mixed endian, could lead to unexpected results/behavior in applications. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-08-29arm64: Add brackets around user_stack_pointer()Catalin Marinas
Commit 5f888a1d33 (ARM64: perf: support dwarf unwinding in compat mode) changes user_stack_pointer() to return the compat SP for 32-bit tasks but without brackets around the whole definition, with possible issues on the call sites (noticed with a subsequent fix for KSTK_ESP). Fixes: 5f888a1d33c4 (ARM64: perf: support dwarf unwinding in compat mode) Reported-by: Sudeep Holla <sudeep.holla@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-07-04arm64: fix el2_setup check of CurrentELMarc Zyngier
The CurrentEL system register reports the Current Exception Level of the CPU. It doesn't say anything about the stack handling, and yet we compare it to PSR_MODE_EL2t and PSR_MODE_EL2h. It works by chance because PSR_MODE_EL2t happens to match the right bits, but that's otherwise a very bad idea. Just check for the EL value instead. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> [catalin.marinas@arm.com: fixed arch/arm64/kernel/efi-entry.S] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-12arm64: Add regs_return_value() in syscall.hAKASHI Takahiro
This macro, regs_return_value, is used mainly for audit to record system call's results, but may also be used in test_kprobes.c. Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-03-13ARM64: perf: support dwarf unwinding in compat modeJean Pihet
Add support for unwinding using the dwarf information in compat mode. Using the correct user stack pointer allows perf to record the frames correctly in the native and compat modes. Note that although the dwarf frame unwinding works ok using libunwind in native mode (on ARMv7 & ARMv8), some changes are required to the libunwind code for the compat mode. Those changes are posted separately on the libunwind mailing list. Tested on ARMv8 platform with v8 and compat v7 binaries, the latter are statically built. Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-03-13ARM64: perf: add support for perf registers APIJean Pihet
This patch implements the functions required for the perf registers API, allowing the perf tool to interface kernel register dumps with libunwind in order to provide userspace backtracing. Compat mode is also supported. Only the general purpose user space registers are exported, i.e.: PERF_REG_ARM_X0, ... PERF_REG_ARM_X28, PERF_REG_ARM_FP, PERF_REG_ARM_LR, PERF_REG_ARM_SP, PERF_REG_ARM_PC and not the PERF_REG_ARM_V* registers. Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-26misc: debug: remove compilation warningsVijaya Kumar K
typecast instruction_pointer macro to unsigned long to resolve following compiler warnings like warning: format '%lx' expects argument of type 'long unsigned int', but argument 2 has type 'u64' [-Wformat] Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25arm64: compat: add support for big-endian (BE8) AArch32 binariesWill Deacon
This patch adds support for BE8 AArch32 tasks to the compat layer. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-06-12arm64: debug: consolidate software breakpoint handlersWill Deacon
The software breakpoint handlers are hooked in directly from ptrace, which makes it difficult to add additional handlers for things like kprobes and kgdb. This patch moves the handling code into debug-monitors.c, where we can dispatch to different debug subsystems more easily. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-01-29arm64: add COMPAT_PSR_*_BIT flagsMarc Zyngier
In order to mess with the processor state when running 32bit guests, define all the AArch32 PSR flags. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-12-05arm64: add AArch32 execution modes to ptrace.hMarc Zyngier
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-12-05arm64: expand register mapping between AArch32 and AArch64Marc Zyngier
The general purpose registers in AArch32 are mapped in an architecturally defined manner into the AArch64 registers. It allows the AArch32 registers of an application or a virtual machine to be inspected by the OS or an hypervisor. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-10-11UAPI: (Scripted) Disintegrate arch/arm64/include/asmDavid Howells
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
2012-10-11arm64: Do not export the compat-specific definitions to the userCatalin Marinas
This patch adds #ifdef __KERNEL__ guards around the COMPAT_* definitions to avoid exporting them to user. AArch32 user requiring the kernel headers must use those generated with ARCH=arm. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com>
2012-09-27arm64: ptrace: remove obsolete ptrace request numbers from user headersWill Deacon
The use of regsets has removed the need for many private ptrace requests, so remove the corresponding definitions from the user-visible ptrace.h Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-09-17arm64: Exception handlingCatalin Marinas
The patch contains the exception entry code (kernel/entry.S), pt_regs structure and related accessors, undefined instruction trapping and stack tracing. AArch64 Linux kernel (including kernel threads) runs in EL1 mode using the SP1 stack. The vectors don't have a fixed address, only alignment (2^11) requirements. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>