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path: root/arch/arm64/kernel/cpufeature.c
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2024-11-05arm64: Add support for FEAT_HAFTYicong Yang
Armv8.9/v9.4 introduces the feature Hardware managed Access Flag for Table descriptors (FEAT_HAFT). The feature is indicated by ID_AA64MMFR1_EL1.HAFDBS == 0b0011 and can be enabled by TCR2_EL1.HAFT so it has a dependency on FEAT_TCR2. Adds the Kconfig for FEAT_HAFT and support detecting and enabling the feature. The feature is enabled in __cpu_setup() before MMU on just like HA. A CPU capability is added to notify the user of the feature. Add definition of P{G,4,U,M}D_TABLE_AF bit and set the AF bit when creating the page table, which will save the hardware from having to update them at runtime. This will be ignored if FEAT_HAFT is not enabled. The AF bit of table descriptors cannot be managed by the software per spec, unlike the HA. So this should be used only if it's supported system wide by system_supports_haft(). Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20241102104235.62560-4-yangyicong@huawei.com Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> [catalin.marinas@arm.com: added the ID check back to __cpu_setup in case of future CPU errata] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-01arm64: Expose ID_AA64ISAR1_EL1.XS to sanitised feature consumersMarc Zyngier
Despite KVM now being able to deal with XS-tagged TLBIs, we still don't expose these feature bits to KVM. Plumb in the feature in ID_AA64ISAR1_EL1. Fixes: 0feec7769a63 ("KVM: arm64: nv: Add handling of NXS-flavoured TLBI operations") Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20241031083519.364313-1-maz@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-31arm64: cpufeature: discover CPU support for MPAMJames Morse
ARMv8.4 adds support for 'Memory Partitioning And Monitoring' (MPAM) which describes an interface to cache and bandwidth controls wherever they appear in the system. Add support to detect MPAM. Like SVE, MPAM has an extra id register that describes some more properties, including the virtualisation support, which is optional. Detect this separately so we can detect mismatched/insane systems, but still use MPAM on the host even if the virtualisation support is missing. MPAM needs enabling at the highest implemented exception level, otherwise the register accesses trap. The 'enabled' flag is accessible to lower exception levels, but its in a register that traps when MPAM isn't enabled. The cpufeature 'matches' hook is extended to test this on one of the CPUs, so that firmware can emulate MPAM as disabled if it is reserved for use by secure world. Secondary CPUs that appear late could trip cpufeature's 'lower safe' behaviour after the MPAM properties have been advertised to user-space. Add a verify call to ensure late secondaries match the existing CPUs. (If you have a boot failure that bisects here its likely your CPUs advertise MPAM in the id registers, but firmware failed to either enable or MPAM, or emulate the trap as if it were disabled) Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Joey Gouly <joey.gouly@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241030160317.2528209-4-joey.gouly@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-17arm64: Support AT_HWCAP3Mark Brown
We have filled all 64 bits of AT_HWCAP2 so in order to support discovery of further features provide the framework to use the already defined AT_HWCAP3 for further CPU features. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241004-arm64-elf-hwcap3-v2-2-799d1daad8b0@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-04arm64/hwcap: Add hwcap for GCSMark Brown
Provide a hwcap to enable userspace to detect support for GCS. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Yury Khrustalev <yury.khrustalev@arm.com> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-18-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-04arm64/cpufeature: Runtime detection of Guarded Control Stack (GCS)Mark Brown
Add a cpufeature for GCS, allowing other code to conditionally support it at runtime. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-12-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-09-04arm64: enable the Permission Overlay Extension for EL0Joey Gouly
Expose a HWCAP and ID_AA64MMFR3_EL1_S1POE to userspace, so they can be used to check if the CPU supports the feature. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-12-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-09-04arm64: cpufeature: add Permission Overlay Extension cpucapJoey Gouly
This indicates if the system supports POE. This is a CPUCAP_BOOT_CPU_FEATURE as the boot CPU will enable POE if it has it, so secondary CPUs must also have this feature. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-6-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-07-04arm64/cpufeature: Replace custom macros with fields from ID_AA64PFR0_EL1Anshuman Khandual
This replaces custom macros usage (i.e ID_AA64PFR0_EL1_ELx_64BIT_ONLY and ID_AA64PFR0_EL1_ELx_32BIT_64BIT) and instead directly uses register fields from ID_AA64PFR0_EL1 sysreg definition. Finally let's drop off both these custom macros as they are now redundant. Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mark Brown <broonie@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20240613102710.3295108-3-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-06-12arm64/cpufeatures/kvm: Add ARMv8.9 FEAT_ECBHB bits in ID_AA64MMFR1 registerNianyao Tang
Enable ECBHB bits in ID_AA64MMFR1 register as per ARM DDI 0487K.a specification. When guest OS read ID_AA64MMFR1_EL1, kvm emulate this reg using ftr_id_aa64mmfr1 and always return ID_AA64MMFR1_EL1.ECBHB=0 to guest. It results in guest syscall jump to tramp ventry, which is not needed in implementation with ID_AA64MMFR1_EL1.ECBHB=1. Let's make the guest syscall process the same as the host. Signed-off-by: Nianyao Tang <tangnianyao@huawei.com> Link: https://lore.kernel.org/r/20240611122049.2758600-1-tangnianyao@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-05-10arm64: errata: Add workaround for Arm errata 3194386 and 3312417Mark Rutland
Cortex-X4 and Neoverse-V3 suffer from errata whereby an MSR to the SSBS special-purpose register does not affect subsequent speculative instructions, permitting speculative store bypassing for a window of time. This is described in their Software Developer Errata Notice (SDEN) documents: * Cortex-X4 SDEN v8.0, erratum 3194386: https://developer.arm.com/documentation/SDEN-2432808/0800/ * Neoverse-V3 SDEN v6.0, erratum 3312417: https://developer.arm.com/documentation/SDEN-2891958/0600/ To workaround these errata, it is necessary to place a speculation barrier (SB) after MSR to the SSBS special-purpose register. This patch adds the requisite SB after writes to SSBS within the kernel, and hides the presence of SSBS from EL0 such that userspace software which cares about SSBS will manipulate this via prctl(PR_GET_SPECULATION_CTRL, ...). 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@kernel.org> Link: https://lore.kernel.org/r/20240508081400.235362-5-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-03-15Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "S390: - Changes to FPU handling came in via the main s390 pull request - Only deliver to the guest the SCLP events that userspace has requested - More virtual vs physical address fixes (only a cleanup since virtual and physical address spaces are currently the same) - Fix selftests undefined behavior x86: - Fix a restriction that the guest can't program a PMU event whose encoding matches an architectural event that isn't included in the guest CPUID. The enumeration of an architectural event only says that if a CPU supports an architectural event, then the event can be programmed *using the architectural encoding*. The enumeration does NOT say anything about the encoding when the CPU doesn't report support the event *in general*. It might support it, and it might support it using the same encoding that made it into the architectural PMU spec - Fix a variety of bugs in KVM's emulation of RDPMC (more details on individual commits) and add a selftest to verify KVM correctly emulates RDMPC, counter availability, and a variety of other PMC-related behaviors that depend on guest CPUID and therefore are easier to validate with selftests than with custom guests (aka kvm-unit-tests) - Zero out PMU state on AMD if the virtual PMU is disabled, it does not cause any bug but it wastes time in various cases where KVM would check if a PMC event needs to be synthesized - Optimize triggering of emulated events, with a nice ~10% performance improvement in VM-Exit microbenchmarks when a vPMU is exposed to the guest - Tighten the check for "PMI in guest" to reduce false positives if an NMI arrives in the host while KVM is handling an IRQ VM-Exit - Fix a bug where KVM would report stale/bogus exit qualification information when exiting to userspace with an internal error exit code - Add a VMX flag in /proc/cpuinfo to report 5-level EPT support - Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for read, e.g. to avoid serializing vCPUs when userspace deletes a memslot - Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB). KVM doesn't support yielding in the middle of processing a zap, and 1GiB granularity resulted in multi-millisecond lags that are quite impolite for CONFIG_PREEMPT kernels - Allocate write-tracking metadata on-demand to avoid the memory overhead when a kernel is built with i915 virtualization support but the workloads use neither shadow paging nor i915 virtualization - Explicitly initialize a variety of on-stack variables in the emulator that triggered KMSAN false positives - Fix the debugregs ABI for 32-bit KVM - Rework the "force immediate exit" code so that vendor code ultimately decides how and when to force the exit, which allowed some optimization for both Intel and AMD - Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if vCPU creation ultimately failed, causing extra unnecessary work - Cleanup the logic for checking if the currently loaded vCPU is in-kernel - Harden against underflowing the active mmu_notifier invalidation count, so that "bad" invalidations (usually due to bugs elsehwere in the kernel) are detected earlier and are less likely to hang the kernel x86 Xen emulation: - Overlay pages can now be cached based on host virtual address, instead of guest physical addresses. This removes the need to reconfigure and invalidate the cache if the guest changes the gpa but the underlying host virtual address remains the same - When possible, use a single host TSC value when computing the deadline for Xen timers in order to improve the accuracy of the timer emulation - Inject pending upcall events when the vCPU software-enables its APIC to fix a bug where an upcall can be lost (and to follow Xen's behavior) - Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen events fails, e.g. if the guest has aliased xAPIC IDs RISC-V: - Support exception and interrupt handling in selftests - New self test for RISC-V architectural timer (Sstc extension) - New extension support (Ztso, Zacas) - Support userspace emulation of random number seed CSRs ARM: - Infrastructure for building KVM's trap configuration based on the architectural features (or lack thereof) advertised in the VM's ID registers - Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to x86's WC) at stage-2, improving the performance of interacting with assigned devices that can tolerate it - Conversion of KVM's representation of LPIs to an xarray, utilized to address serialization some of the serialization on the LPI injection path - Support for _architectural_ VHE-only systems, advertised through the absence of FEAT_E2H0 in the CPU's ID register - Miscellaneous cleanups, fixes, and spelling corrections to KVM and selftests LoongArch: - Set reserved bits as zero in CPUCFG - Start SW timer only when vcpu is blocking - Do not restart SW timer when it is expired - Remove unnecessary CSR register saving during enter guest - Misc cleanups and fixes as usual Generic: - Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically always true on all architectures except MIPS (where Kconfig determines the available depending on CPU capabilities). It is replaced either by an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM) everywhere else - Factor common "select" statements in common code instead of requiring each architecture to specify it - Remove thoroughly obsolete APIs from the uapi headers - Move architecture-dependent stuff to uapi/asm/kvm.h - Always flush the async page fault workqueue when a work item is being removed, especially during vCPU destruction, to ensure that there are no workers running in KVM code when all references to KVM-the-module are gone, i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded - Grab a reference to the VM's mm_struct in the async #PF worker itself instead of gifting the worker a reference, so that there's no need to remember to *conditionally* clean up after the worker Selftests: - Reduce boilerplate especially when utilize selftest TAP infrastructure - Add basic smoke tests for SEV and SEV-ES, along with a pile of library support for handling private/encrypted/protected memory - Fix benign bugs where tests neglect to close() guest_memfd files" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits) selftests: kvm: remove meaningless assignments in Makefiles KVM: riscv: selftests: Add Zacas extension to get-reg-list test RISC-V: KVM: Allow Zacas extension for Guest/VM KVM: riscv: selftests: Add Ztso extension to get-reg-list test RISC-V: KVM: Allow Ztso extension for Guest/VM RISC-V: KVM: Forward SEED CSR access to user space KVM: riscv: selftests: Add sstc timer test KVM: riscv: selftests: Change vcpu_has_ext to a common function KVM: riscv: selftests: Add guest helper to get vcpu id KVM: riscv: selftests: Add exception handling support LoongArch: KVM: Remove unnecessary CSR register saving during enter guest LoongArch: KVM: Do not restart SW timer when it is expired LoongArch: KVM: Start SW timer only when vcpu is blocking LoongArch: KVM: Set reserved bits as zero in CPUCFG KVM: selftests: Explicitly close guest_memfd files in some gmem tests KVM: x86/xen: fix recursive deadlock in timer injection KVM: pfncache: simplify locking and make more self-contained KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled KVM: x86/xen: improve accuracy of Xen timers ...
2024-03-07Merge branch 'for-next/stage1-lpa2' into for-next/coreCatalin Marinas
* for-next/stage1-lpa2: (48 commits) : Add support for LPA2 and WXN and stage 1 arm64/mm: Avoid ID mapping of kpti flag if it is no longer needed arm64/mm: Use generic __pud_free() helper in pud_free() implementation arm64: gitignore: ignore relacheck arm64: Use Signed/Unsigned enums for TGRAN{4,16,64} and VARange arm64: mm: Make PUD folding check in set_pud() a runtime check arm64: mm: add support for WXN memory translation attribute mm: add arch hook to validate mmap() prot flags arm64: defconfig: Enable LPA2 support arm64: Enable 52-bit virtual addressing for 4k and 16k granule configs arm64: kvm: avoid CONFIG_PGTABLE_LEVELS for runtime levels arm64: ptdump: Deal with translation levels folded at runtime arm64: ptdump: Disregard unaddressable VA space arm64: mm: Add support for folding PUDs at runtime arm64: kasan: Reduce minimum shadow alignment and enable 5 level paging arm64: mm: Add 5 level paging support to fixmap and swapper handling arm64: Enable LPA2 at boot if supported by the system arm64: mm: add LPA2 and 5 level paging support to G-to-nG conversion arm64: mm: Add definitions to support 5 levels of paging arm64: mm: Add LPA2 support to phys<->pte conversion routines arm64: mm: Wire up TCR.DS bit to PTE shareability fields ...
2024-03-07Merge branches 'for-next/reorg-va-space', 'for-next/rust-for-arm64', ↵Catalin Marinas
'for-next/misc', 'for-next/daif-cleanup', 'for-next/kselftest', 'for-next/documentation', 'for-next/sysreg' and 'for-next/dpisa', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: (39 commits) docs: perf: Fix build warning of hisi-pcie-pmu.rst perf: starfive: Only allow COMPILE_TEST for 64-bit architectures MAINTAINERS: Add entry for StarFive StarLink PMU docs: perf: Add description for StarFive's StarLink PMU dt-bindings: perf: starfive: Add JH8100 StarLink PMU perf: starfive: Add StarLink PMU support docs: perf: Update usage for target filter of hisi-pcie-pmu drivers/perf: hisi_pcie: Merge find_related_event() and get_event_idx() drivers/perf: hisi_pcie: Relax the check on related events drivers/perf: hisi_pcie: Check the target filter properly drivers/perf: hisi_pcie: Add more events for counting TLP bandwidth drivers/perf: hisi_pcie: Fix incorrect counting under metric mode drivers/perf: hisi_pcie: Introduce hisi_pcie_pmu_get_event_ctrl_val() drivers/perf: hisi_pcie: Rename hisi_pcie_pmu_{config,clear}_filter() drivers/perf: hisi: Enable HiSilicon Erratum 162700402 quirk for HIP09 perf/arm_cspmu: Add devicetree support dt-bindings/perf: Add Arm CoreSight PMU perf/arm_cspmu: Simplify counter reset perf/arm_cspmu: Simplify attribute groups perf/arm_cspmu: Simplify initialisation ... * for-next/reorg-va-space: : Reorganise the arm64 kernel VA space in preparation for LPA2 support : (52-bit VA/PA). arm64: kaslr: Adjust randomization range dynamically arm64: mm: Reclaim unused vmemmap region for vmalloc use arm64: vmemmap: Avoid base2 order of struct page size to dimension region arm64: ptdump: Discover start of vmemmap region at runtime arm64: ptdump: Allow all region boundaries to be defined at boot time arm64: mm: Move fixmap region above vmemmap region arm64: mm: Move PCI I/O emulation region above the vmemmap region * for-next/rust-for-arm64: : Enable Rust support for arm64 arm64: rust: Enable Rust support for AArch64 rust: Refactor the build target to allow the use of builtin targets * for-next/misc: : Miscellaneous arm64 patches ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512 arm64: Remove enable_daif macro arm64/hw_breakpoint: Directly use ESR_ELx_WNR for an watchpoint exception arm64: cpufeatures: Clean up temporary variable to simplify code arm64: Update setup_arch() comment on interrupt masking arm64: remove unnecessary ifdefs around is_compat_task() arm64: ftrace: Don't forbid CALL_OPS+CC_OPTIMIZE_FOR_SIZE with Clang arm64/sme: Ensure that all fields in SMCR_EL1 are set to known values arm64/sve: Ensure that all fields in ZCR_EL1 are set to known values arm64/sve: Document that __SVE_VQ_MAX is much larger than needed arm64: make member of struct pt_regs and it's offset macro in the same order arm64: remove unneeded BUILD_BUG_ON assertion arm64: kretprobes: acquire the regs via a BRK exception arm64: io: permit offset addressing arm64: errata: Don't enable workarounds for "rare" errata by default * for-next/daif-cleanup: : Clean up DAIF handling for EL0 returns arm64: Unmask Debug + SError in do_notify_resume() arm64: Move do_notify_resume() to entry-common.c arm64: Simplify do_notify_resume() DAIF masking * for-next/kselftest: : Miscellaneous arm64 kselftest patches kselftest/arm64: Test that ptrace takes effect in the target process * for-next/documentation: : arm64 documentation patches arm64/sme: Remove spurious 'is' in SME documentation arm64/fp: Clarify effect of setting an unsupported system VL arm64/sme: Fix cut'n'paste in ABI document arm64/sve: Remove bitrotted comment about syscall behaviour * for-next/sysreg: : sysreg updates arm64/sysreg: Update ID_AA64DFR0_EL1 register arm64/sysreg: Update ID_DFR0_EL1 register fields arm64/sysreg: Add register fields for ID_AA64DFR1_EL1 * for-next/dpisa: : Support for 2023 dpISA extensions kselftest/arm64: Add 2023 DPISA hwcap test coverage kselftest/arm64: Add basic FPMR test kselftest/arm64: Handle FPMR context in generic signal frame parser arm64/hwcap: Define hwcaps for 2023 DPISA features arm64/ptrace: Expose FPMR via ptrace arm64/signal: Add FPMR signal handling arm64/fpsimd: Support FEAT_FPMR arm64/fpsimd: Enable host kernel access to FPMR arm64/cpufeature: Hook new identification registers up to cpufeature
2024-03-07arm64/hwcap: Define hwcaps for 2023 DPISA featuresMark Brown
The 2023 architecture extensions include a large number of floating point features, most of which simply add new instructions. Add hwcaps so that userspace can enumerate these features. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-6-c568edc8ed7f@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-03-07arm64/fpsimd: Support FEAT_FPMRMark Brown
FEAT_FPMR defines a new EL0 accessible register FPMR use to configure the FP8 related features added to the architecture at the same time. Detect support for this register and context switch it for EL0 when present. Due to the sharing of responsibility for saving floating point state between the host kernel and KVM FP8 support is not yet implemented in KVM and a stub similar to that used for SVCR is provided for FPMR in order to avoid bisection issues. To make it easier to share host state with the hypervisor we store FPMR as a hardened usercopy field in uw (along with some padding). Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-3-c568edc8ed7f@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-03-07arm64/cpufeature: Hook new identification registers up to cpufeatureMark Brown
The 2023 architecture extensions have defined several new ID registers, hook them up to the cpufeature code so we can add feature checks and hwcaps based on their contents. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-1-c568edc8ed7f@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-03-01arm64: cpufeatures: Clean up temporary variable to simplify codeLiao Chang
Clean up one temporary variable to simplifiy code in capability detection. Signed-off-by: Liao Chang <liaochang1@huawei.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20240229105208.456704-1-liaochang1@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-19arm64: Use Signed/Unsigned enums for TGRAN{4,16,64} and VARangeMarc Zyngier
Open-coding the feature matching parameters for LVA/LVA2 leads to issues with upcoming changes to the cpufeature code. By making TGRAN{4,16,64} and VARange signed/unsigned as per the architecture, we can use the existing macros, making the feature match robust against those changes. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: Enable 52-bit virtual addressing for 4k and 16k granule configsArd Biesheuvel
Update Kconfig to permit 4k and 16k granule configurations to be built with 52-bit virtual addressing, now that all the prerequisites are in place. While at it, update the feature description so it matches on the appropriate feature bits depending on the page size. For simplicity, let's just keep ARM64_HAS_VA52 as the feature name. Note that LPA2 based 52-bit virtual addressing requires 52-bit physical addressing support to be enabled as well, as programming TCR.TxSZ to values below 16 is not allowed unless TCR.DS is set, which is what activates the 52-bit physical addressing support. While supporting the converse (52-bit physical addressing without 52-bit virtual addressing) would be possible in principle, let's keep things simple, by only allowing these features to be enabled at the same time. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-85-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: mm: Add support for folding PUDs at runtimeArd Biesheuvel
In order to support LPA2 on 16k pages in a way that permits non-LPA2 systems to run the same kernel image, we have to be able to fall back to at most 48 bits of virtual addressing. Falling back to 48 bits would result in a level 0 with only 2 entries, which is suboptimal in terms of TLB utilization. So instead, let's fall back to 47 bits in that case. This means we need to be able to fold PUDs dynamically, similar to how we fold P4Ds for 48 bit virtual addressing on LPA2 with 4k pages. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-81-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: mm: add LPA2 and 5 level paging support to G-to-nG conversionArd Biesheuvel
Add support for 5 level paging in the G-to-nG routine that creates its own temporary page tables to traverse the swapper page tables. Also add support for running the 5 level configuration with the top level folded at runtime, to support CPUs that do not implement the LPA2 extension. While at it, wire up the level skipping logic so it will also trigger on 4 level configurations with LPA2 enabled at build time but not active at runtime, as we'll fall back to 3 level paging in that case. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-77-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: mm: Add feature override support for LVAArd Biesheuvel
Add support for overriding the VARange field of the MMFR2 CPU ID register. This permits the associated LVA feature to be overridden early enough for the boot code that creates the kernel mapping to take it into account. Given that LPA2 implies LVA, disabling the latter should disable the former as well. So override the ID_AA64MMFR0.TGran field of the current page size as well if it advertises support for 52-bit addressing. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-71-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: mm: Handle LVA support as a CPU featureArd Biesheuvel
Currently, we detect CPU support for 52-bit virtual addressing (LVA) extremely early, before creating the kernel page tables or enabling the MMU. We cannot override the feature this early, and so large virtual addressing is always enabled on CPUs that implement support for it if the software support for it was enabled at build time. It also means we rely on non-trivial code in asm to deal with this feature. Given that both the ID map and the TTBR1 mapping of the kernel image are guaranteed to be 48-bit addressable, it is not actually necessary to enable support this early, and instead, we can model it as a CPU feature. That way, we can rely on code patching to get the correct TCR.T1SZ values programmed on secondary boot and resume from suspend. On the primary boot path, we simply enable the MMU with 48-bit virtual addressing initially, and update TCR.T1SZ if LVA is supported from C code, right before creating the kernel mapping. Given that TTBR1 still points to reserved_pg_dir at this point, updating TCR.T1SZ should be safe without the need for explicit TLB maintenance. Since this gets rid of all accesses to the vabits_actual variable from asm code that occurred before TCR.T1SZ had been programmed, we no longer have a need for this variable, and we can replace it with a C expression that produces the correct value directly, based on the value of TCR.T1SZ. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-70-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: mm: Make kaslr_requires_kpti() a static inlineArd Biesheuvel
In preparation for moving the first assignment of arm64_use_ng_mappings to an earlier stage in the boot, ensure that kaslr_requires_kpti() is accessible without relying on the core kernel's view on whether or not KASLR is enabled. So make it a static inline, and move the kaslr_enabled() check out of it and into the callers, one of which will disappear in a subsequent patch. Once/when support for the obsolete ThunderX 1 platform is dropped, this check reduces to a E0PD feature check on the local CPU. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-61-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: cpufeature: Add helper to test for CPU feature overridesArd Biesheuvel
Add some helpers to extract and apply feature overrides to the bare idreg values. This involves inspecting the value and mask of the specific field that we are interested in, given that an override value/mask pair might be invalid for one field but valid for another. Then, wire up the new helper for the hVHE test - note that we can drop the sysreg test here, as the override will be invalid when trying to enable hVHE on non-VHE capable hardware. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-55-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-16arm64: Move feature overrides into the BSS sectionArd Biesheuvel
In order to allow the CPU feature override detection code to run even earlier, move the feature override global variables into BSS, which is the only part of the static kernel image that is mapped read-write in the initial ID map. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240214122845.2033971-52-ardb+git@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-02-15arm64: cpufeatures: Fix FEAT_NV check when checking for FEAT_NV1Marc Zyngier
Using this_cpu_has_cap() has the potential to go wrong when used system-wide on a preemptible kernel. Instead, use the __system_matches_cap() helper when checking for FEAT_NV in the FEAT_NV1 probing helper. Fixes: 3673d01a2f55 ("arm64: cpufeatures: Only check for NV1 if NV is present") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/kvmarm/86bk8k5ts3.wl-maz@kernel.org/ Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-12arm64: cpufeatures: Only check for NV1 if NV is presentMarc Zyngier
We handle ID_AA64MMFR4_EL1.E2H0 being 0 as NV1 being present. However, this is only true if FEAT_NV is implemented. Add the required check to has_nv1(), avoiding spuriously advertising NV1 on HW that doesn't have NV at all. Fixes: da9af5071b25 ("arm64: cpufeature: Detect HCR_EL2.NV1 being RES0") Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240212144736.1933112-3-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-12arm64: cpufeatures: Add missing ID_AA64MMFR4_EL1 to __read_sysreg_by_encoding()Marc Zyngier
When triggering a CPU hotplug scenario, we reparse the CPU feature with SCOPE_LOCAL_CPU, for which we use __read_sysreg_by_encoding() to get the HW value for this CPU. As it turns out, we're missing the handling for ID_AA64MMFR4_EL1, and trigger a BUG(). Funnily enough, Marek isn't completely happy about that. Add the damn register to the list. Fixes: 805bb61f8279 ("arm64: cpufeature: Add ID_AA64MMFR4_EL1 handling") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240212144736.1933112-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-08KVM: arm64: Handle Apple M2 as not having HCR_EL2.NV1 implementedMarc Zyngier
Although the Apple M2 family of CPUs can have HCR_EL2.NV1 being set and clear, with the change in trap behaviour being OK, they explode spectacularily on an EL2 S1 page table using the nVHE format. This is no good. Let's pretend this HW doesn't have NV1, and move along. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-11-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-08arm64: cpufeature: Detect HCR_EL2.NV1 being RES0Marc Zyngier
A variant of FEAT_E2H0 not being implemented exists in the form of HCR_EL2.E2H being RES1 *and* HCR_EL2.NV1 being RES0 (indicating that only VHE is supported on the host and nested guests). Add the necessary infrastructure for this new CPU capability. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-7-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-08arm64: cpufeature: Add ID_AA64MMFR4_EL1 handlingMarc Zyngier
Add ID_AA64MMFR4_EL1 to the list of idregs the kernel knows about, and describe the E2H0 field. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-6-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-08arm64: cpufeature: Correctly display signed override valuesMarc Zyngier
When a field gets overriden, the kernel indicates the result of the override in dmesg. This works well with unsigned fields, but results in a pretty ugly output when the field is signed. Truncate the field to its width before displaying it. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-4-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-08arm64: cpufeatures: Correctly handle signed valuesMarc Zyngier
Although we've had signed values for some features such as PMUv3 and FP, the code that handles the comparaison with some limit has a couple of annoying issues: - the min_field_value is always unsigned, meaning that we cannot easily compare it with a negative value - it is not possible to have a range of values, let alone a range of negative values Fix this by: - adding an upper limit to the comparison, defaulting to all bits being set to the maximum positive value - ensuring that the signess of the min and max values are taken into account A ARM64_CPUID_FIELDS_NEG() macro is provided for signed features, but nothing is using it yet. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-3-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-01-17Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "Generic: - Use memdup_array_user() to harden against overflow. - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures. - Clean up Kconfigs that all KVM architectures were selecting - New functionality around "guest_memfd", a new userspace API that creates an anonymous file and returns a file descriptor that refers to it. guest_memfd files are bound to their owning virtual machine, cannot be mapped, read, or written by userspace, and cannot be resized. guest_memfd files do however support PUNCH_HOLE, which can be used to switch a memory area between guest_memfd and regular anonymous memory. - New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify per-page attributes for a given page of guest memory; right now the only attribute is whether the guest expects to access memory via guest_memfd or not, which in Confidential SVMs backed by SEV-SNP, TDX or ARM64 pKVM is checked by firmware or hypervisor that guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in the case of pKVM). x86: - Support for "software-protected VMs" that can use the new guest_memfd and page attributes infrastructure. This is mostly useful for testing, since there is no pKVM-like infrastructure to provide a meaningfully reduced TCB. - Fix a relatively benign off-by-one error when splitting huge pages during CLEAR_DIRTY_LOG. - Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE. - Use more generic lockdep assertions in paths that don't actually care about whether the caller is a reader or a writer. - let Xen guests opt out of having PV clock reported as "based on a stable TSC", because some of them don't expect the "TSC stable" bit (added to the pvclock ABI by KVM, but never set by Xen) to be set. - Revert a bogus, made-up nested SVM consistency check for TLB_CONTROL. - Advertise flush-by-ASID support for nSVM unconditionally, as KVM always flushes on nested transitions, i.e. always satisfies flush requests. This allows running bleeding edge versions of VMware Workstation on top of KVM. - Sanity check that the CPU supports flush-by-ASID when enabling SEV support. - On AMD machines with vNMI, always rely on hardware instead of intercepting IRET in some cases to detect unmasking of NMIs - Support for virtualizing Linear Address Masking (LAM) - Fix a variety of vPMU bugs where KVM fail to stop/reset counters and other state prior to refreshing the vPMU model. - Fix a double-overflow PMU bug by tracking emulated counter events using a dedicated field instead of snapshotting the "previous" counter. If the hardware PMC count triggers overflow that is recognized in the same VM-Exit that KVM manually bumps an event count, KVM would pend PMIs for both the hardware-triggered overflow and for KVM-triggered overflow. - Turn off KVM_WERROR by default for all configs so that it's not inadvertantly enabled by non-KVM developers, which can be problematic for subsystems that require no regressions for W=1 builds. - Advertise all of the host-supported CPUID bits that enumerate IA32_SPEC_CTRL "features". - Don't force a masterclock update when a vCPU synchronizes to the current TSC generation, as updating the masterclock can cause kvmclock's time to "jump" unexpectedly, e.g. when userspace hotplugs a pre-created vCPU. - Use RIP-relative address to read kvm_rebooting in the VM-Enter fault paths, partly as a super minor optimization, but mostly to make KVM play nice with position independent executable builds. - Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on CONFIG_HYPERV as a minor optimization, and to self-document the code. - Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation" at build time. ARM64: - LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base granule sizes. Branch shared with the arm64 tree. - Large Fine-Grained Trap rework, bringing some sanity to the feature, although there is more to come. This comes with a prefix branch shared with the arm64 tree. - Some additional Nested Virtualization groundwork, mostly introducing the NV2 VNCR support and retargetting the NV support to that version of the architecture. - A small set of vgic fixes and associated cleanups. Loongarch: - Optimization for memslot hugepage checking - Cleanup and fix some HW/SW timer issues - Add LSX/LASX (128bit/256bit SIMD) support RISC-V: - KVM_GET_REG_LIST improvement for vector registers - Generate ISA extension reg_list using macros in get-reg-list selftest - Support for reporting steal time along with selftest s390: - Bugfixes Selftests: - Fix an annoying goof where the NX hugepage test prints out garbage instead of the magic token needed to run the test. - Fix build errors when a header is delete/moved due to a missing flag in the Makefile. - Detect if KVM bugged/killed a selftest's VM and print out a helpful message instead of complaining that a random ioctl() failed. - Annotate the guest printf/assert helpers with __printf(), and fix the various bugs that were lurking due to lack of said annotation" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits) x86/kvm: Do not try to disable kvmclock if it was not enabled KVM: x86: add missing "depends on KVM" KVM: fix direction of dependency on MMU notifiers KVM: introduce CONFIG_KVM_COMMON KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache RISC-V: KVM: selftests: Add get-reg-list test for STA registers RISC-V: KVM: selftests: Add steal_time test support RISC-V: KVM: selftests: Add guest_sbi_probe_extension RISC-V: KVM: selftests: Move sbi_ecall to processor.c RISC-V: KVM: Implement SBI STA extension RISC-V: KVM: Add support for SBI STA registers RISC-V: KVM: Add support for SBI extension registers RISC-V: KVM: Add SBI STA info to vcpu_arch RISC-V: KVM: Add steal-update vcpu request RISC-V: KVM: Add SBI STA extension skeleton RISC-V: paravirt: Implement steal-time support RISC-V: Add SBI STA extension definitions RISC-V: paravirt: Add skeleton for pv-time support RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr() ...
2024-01-08Merge tag 'kvmarm-6.8' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 6.8 - LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base granule sizes. Branch shared with the arm64 tree. - Large Fine-Grained Trap rework, bringing some sanity to the feature, although there is more to come. This comes with a prefix branch shared with the arm64 tree. - Some additional Nested Virtualization groundwork, mostly introducing the NV2 VNCR support and retargetting the NV support to that version of the architecture. - A small set of vgic fixes and associated cleanups.
2024-01-04Merge branch 'for-next/fixes' into for-next/coreWill Deacon
Merge in arm64 fixes queued for 6.7 so that kpti_install_ng_mappings() can be updated to use arm64_kernel_unmapped_at_el0() instead of checking the ARM64_UNMAP_KERNEL_AT_EL0 CPU capability directly. * for-next/fixes: arm64: mm: Always make sw-dirty PTEs hw-dirty in pte_modify perf/arm-cmn: Fail DTC counter allocation correctly arm64: Avoid enabling KPTI unnecessarily
2024-01-04Merge branch 'for-next/lpa2-prep' into for-next/coreWill Deacon
* for-next/lpa2-prep: arm64: mm: get rid of kimage_vaddr global variable arm64: mm: Take potential load offset into account when KASLR is off arm64: kernel: Disable latent_entropy GCC plugin in early C runtime arm64: Add ARM64_HAS_LPA2 CPU capability arm64/mm: Add FEAT_LPA2 specific ID_AA64MMFR0.TGRAN[2] arm64/mm: Update tlb invalidation routines for FEAT_LPA2 arm64/mm: Add lpa2_is_enabled() kvm_lpa2_is_enabled() stubs arm64/mm: Modify range-based tlbi to decrement scale
2023-12-19Merge branch kvm-arm64/nv-6.8-prefix into kvmarm-master/nextMarc Zyngier
* kvm-arm64/nv-6.8-prefix: : . : Nested Virtualization support update, focussing on the : NV2 support (VNCR mapping and such). : . KVM: arm64: nv: Handle virtual EL2 registers in vcpu_read/write_sys_reg() KVM: arm64: nv: Map VNCR-capable registers to a separate page KVM: arm64: nv: Add EL2_REG_VNCR()/EL2_REG_REDIR() sysreg helpers KVM: arm64: Introduce a bad_trap() primitive for unexpected trap handling KVM: arm64: nv: Add include containing the VNCR_EL2 offsets KVM: arm64: nv: Add non-VHE-EL2->EL1 translation helpers KVM: arm64: nv: Drop EL12 register traps that are redirected to VNCR KVM: arm64: nv: Compute NV view of idregs as a one-off KVM: arm64: nv: Hoist vcpu_has_nv() into is_hyp_ctxt() arm64: cpufeatures: Restrict NV support to FEAT_NV2 Signed-off-by: Marc Zyngier <maz@kernel.org>
2023-12-19arm64: cpufeatures: Restrict NV support to FEAT_NV2Marc Zyngier
To anyone who has played with FEAT_NV, it is obvious that the level of performance is rather low due to the trap amplification that it imposes on the host hypervisor. FEAT_NV2 solves a number of the problems that FEAT_NV had. It also turns out that all the existing hardware that has FEAT_NV also has FEAT_NV2. Finally, it is now allowed by the architecture to build FEAT_NV2 *only* (as denoted by ID_AA64MMFR4_EL1.NV_frac), which effectively seals the fate of FEAT_NV. Restrict the NV support to NV2, and be done with it. Nobody will cry over the old crap. NV_frac will eventually be supported once the intrastructure is ready. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Marc Zyngier <maz@kernel.org>
2023-12-13arm64: Align boot cpucap handling with system cpucap handlingMark Rutland
Currently the detection+enablement of boot cpucaps is separate from the patching of boot cpucap alternatives, which means there's a period where cpus_have_cap($CAP) and alternative_has_cap($CAP) may be mismatched. It would be preferable to manage the boot cpucaps in the same way as the system cpucaps, both for clarity and to minimize the risk of accidental usage of code relying upon an alternative which has not yet been patched. This patch aligns the handling of boot cpucaps with the handling of system cpucaps: * The existing setup_boot_cpu_capabilities() function is moved to be closer to the setup_system_capabilities() and setup_system_features() functions so that they're more clearly related and more likely to be updated together in future. * The patching of boot cpucap alternatives is moved into setup_boot_cpu_capabilities(), immediately after boot cpucaps are detected and enabled. * A new setup_boot_cpu_features() function is added to mirror setup_system_features(); this handles initialization of cpucap data structures and calls setup_boot_cpu_capabilities(). This makes init_cpu_features() a closer mirror to update_cpu_features(), and makes smp_prepare_boot_cpu() a closer mirror to smp_cpus_done(). Importantly, while these changes alter the structure of the code, they retain the existing order of calls to: init_cpu_features(); // prefix initializing feature regs init_cpucap_indirect_list(); detect_system_supports_pseudo_nmi(); update_cpu_capabilities(SCOPE_BOOT_CPU | SCOPE_LOCAL_CPU); enable_cpu_capabilities(SCOPE_BOOT_CPU); apply_boot_alternatives(); ... and hence there should be no functional change as a result of this patch; this is purely a structural cleanup. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20231212170910.3745497-3-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2023-12-13arm64: Cleanup system cpucap handlingMark Rutland
Recent changes to remove cpus_have_const_cap() introduced new users of cpus_have_cap() in the period between detecting system cpucaps and patching alternatives. It would be preferable to defer these until after the relevant cpucaps have been patched so that these can use the usual feature check helper functions, which is clearer and has less risk of accidental usage of code relying upon an alternative which has not yet been patched. This patch reworks the system-wide cpucap detection and patching to minimize this transient period: * The detection, enablement, and patching of system cpucaps is moved into a new setup_system_capabilities() function so that these can be grouped together more clearly, with no other functions called in the period between detection and patching. This is called from setup_system_features() before the subsequent checks that depend on the cpucaps. The logging of TTBR0 PAN and cpucaps with a mask is also moved here to keep these as close as possible to update_cpu_capabilities(). At the same time, comments are corrected and improved to make the intent clearer. * As hyp_mode_check() only tests system register values (not hwcaps) and must be called prior to patching, the call to hyp_mode_check() is moved before the call to setup_system_features(). * In setup_system_features(), the use of system_uses_ttbr0_pan() is restored, now that this occurs after alternatives are patched. This is a partial revert of commit: 53d62e995d9eaed1 ("arm64: Avoid cpus_have_const_cap() for ARM64_HAS_PAN") * In sve_setup() and sme_setup(), the use of system_supports_sve() and system_supports_sme() respectively are restored, now that these occur after alternatives are patched. This is a partial revert of commit: a76521d160284a1e ("arm64: Avoid cpus_have_const_cap() for ARM64_{SVE,SME,SME2,FA64}") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20231212170910.3745497-2-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2023-12-05arm64: Get rid of ARM64_HAS_NO_HW_PREFETCHMarc Zyngier
Back in 2016, it was argued that implementations lacking a HW prefetcher could be helped by sprinkling a number of PRFM instructions in strategic locations. In 2023, the one platform that presumably needed this hack is no longer in active use (let alone maintained), and an quick experiment shows dropping this hack only leads to a 0.4% drop on a full kernel compilation (tested on a MT30-GS0 48 CPU system). Given that this is pretty much in the noise department and that it may give odd ideas to other implementers, drop the hack for good. Suggested-by: Will Deacon <will@kernel.org> Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20231122133754.1240687-1-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2023-11-30arm64: Avoid enabling KPTI unnecessarilyArd Biesheuvel
Commit 42c5a3b04bf6 refactored the KPTI init code in a way that results in the use of non-global kernel mappings even on systems that have no need for it, and even when KPTI has been disabled explicitly via the command line. Ensure that this only happens when we have decided (based on the detected system-wide CPU features) that KPTI should be enabled. Fixes: 42c5a3b04bf6 ("arm64: Split kpti_install_ng_mappings()") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20231127120049.2258650-6-ardb@google.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-11-27arm64: Add ARM64_HAS_LPA2 CPU capabilityRyan Roberts
Expose FEAT_LPA2 as a capability so that we can take advantage of alternatives patching in the hypervisor. Although FEAT_LPA2 presence is advertised separately for stage1 and stage2, the expectation is that in practice both stages will either support or not support it. Therefore, we combine both into a single capability, allowing us to simplify the implementation. KVM requires support in both stages in order to use LPA2 since the same library is used for hyp stage 1 and guest stage 2 pgtables. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231127111737.1897081-6-ryan.roberts@arm.com
2023-11-08arm64: Move MediaTek GIC quirk handling from irqchip to coreDouglas Anderson
In commit 44bd78dd2b88 ("irqchip/gic-v3: Disable pseudo NMIs on MediaTek devices w/ firmware issues") we added a method for detecting MediaTek devices with broken firmware and disabled pseudo-NMI. While that worked, it didn't address the problem at a deep enough level. The fundamental issue with this broken firmware is that it's not saving and restoring several important GICR registers. The current list is believed to be: * GICR_NUM_IPRIORITYR * GICR_CTLR * GICR_ISPENDR0 * GICR_ISACTIVER0 * GICR_NSACR Pseudo-NMI didn't work because it was the only thing (currently) in the kernel that relied on the broken registers, so forcing pseudo-NMI off was an effective fix. However, it could be observed that calling system_uses_irq_prio_masking() on these systems still returned "true". That caused confusion and led to the need for commit a07a59415217 ("arm64: smp: avoid NMI IPIs with broken MediaTek FW"). It's worried that the incorrect value returned by system_uses_irq_prio_masking() on these systems will continue to confuse future developers. Let's fix the issue a little more completely by disabling IRQ priorities at a deeper level in the kernel. Once we do this we can revert some of the other bits of code dealing with this quirk. This includes a partial revert of commit 44bd78dd2b88 ("irqchip/gic-v3: Disable pseudo NMIs on MediaTek devices w/ firmware issues"). This isn't a full revert because it leaves some of the changes to the "quirks" structure around in case future code needs it. Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20231107072651.v2.1.Ide945748593cffd8ff0feb9ae22b795935b944d6@changeid Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-10-26Merge branch 'for-next/cpus_have_const_cap' into for-next/coreCatalin Marinas
* for-next/cpus_have_const_cap: (38 commits) : cpus_have_const_cap() removal arm64: Remove cpus_have_const_cap() arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_REPEAT_TLBI arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_NVIDIA_CARMEL_CNP arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_CAVIUM_23154 arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_2645198 arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_1742098 arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_1542419 arm64: Avoid cpus_have_const_cap() for ARM64_WORKAROUND_843419 arm64: Avoid cpus_have_const_cap() for ARM64_UNMAP_KERNEL_AT_EL0 arm64: Avoid cpus_have_const_cap() for ARM64_{SVE,SME,SME2,FA64} arm64: Avoid cpus_have_const_cap() for ARM64_SPECTRE_V2 arm64: Avoid cpus_have_const_cap() for ARM64_SSBS arm64: Avoid cpus_have_const_cap() for ARM64_MTE arm64: Avoid cpus_have_const_cap() for ARM64_HAS_TLB_RANGE arm64: Avoid cpus_have_const_cap() for ARM64_HAS_WFXT arm64: Avoid cpus_have_const_cap() for ARM64_HAS_RNG arm64: Avoid cpus_have_const_cap() for ARM64_HAS_EPAN arm64: Avoid cpus_have_const_cap() for ARM64_HAS_PAN arm64: Avoid cpus_have_const_cap() for ARM64_HAS_GIC_PRIO_MASKING arm64: Avoid cpus_have_const_cap() for ARM64_HAS_DIT ...
2023-10-26Merge branch 'for-next/feat_lse128' into for-next/coreCatalin Marinas
* for-next/feat_lse128: : HWCAP for FEAT_LSE128 kselftest/arm64: add FEAT_LSE128 to hwcap test arm64: add FEAT_LSE128 HWCAP
2023-10-26Merge branch 'for-next/feat_lrcpc3' into for-next/coreCatalin Marinas
* for-next/feat_lrcpc3: : HWCAP for FEAT_LRCPC3 selftests/arm64: add HWCAP2_LRCPC3 test arm64: add FEAT_LRCPC3 HWCAP