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* docs: arm64: Move arm64 documentation under Documentation/arch/Jonathan Corbet2023-06-211-400/+0
| | | | | | | | | | | | | | | | Architecture-specific documentation is being moved into Documentation/arch/ as a way of cleaning up the top-level documentation directory and making the docs hierarchy more closely match the source hierarchy. Move Documentation/arm64 into arch/ (along with the Chinese equvalent translations) and fix up documentation references. Cc: Will Deacon <will@kernel.org> Cc: Alex Shi <alexs@kernel.org> Cc: Hu Haowen <src.res@email.cn> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Yantengsi <siyanteng@loongson.cn> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* arm64: cpufeature: Fix the visibility of compat hwcapsAmit Daniel Kachhap2022-11-031-1/+37
| | | | | | | | | | | | | | | | | | | | | | | | Commit 237405ebef58 ("arm64: cpufeature: Force HWCAP to be based on the sysreg visible to user-space") forced the hwcaps to use sanitised user-space view of the id registers. However, the ID register structures used to select few compat cpufeatures (vfp, crc32, ...) are masked and hence such hwcaps do not appear in /proc/cpuinfo anymore for PER_LINUX32 personality. Add the ID register structures explicitly and set the relevant entry as visible. As these ID registers are now of type visible so make them available in 64-bit userspace by making necessary changes in register emulation logic and documentation. While at it, update the comment for structure ftr_generic_32bits[] which lists the ID register that use it. Fixes: 237405ebef58 ("arm64: cpufeature: Force HWCAP to be based on the sysreg visible to user-space") Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Link: https://lore.kernel.org/r/20221103082232.19189-1-amit.kachhap@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: Add HWCAP advertising FEAT_WFXTMarc Zyngier2022-04-201-0/+2
| | | | | | | | | In order to allow userspace to enjoy WFET, add a new HWCAP that advertises it when available. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220419182755.601427-9-maz@kernel.org
* arm64: cpufeature: add HWCAP for FEAT_RPRESJoey Gouly2021-12-131-0/+8
| | | | | | | | | | | | | | Add a new HWCAP to detect the Increased precision of Reciprocal Estimate and Reciprocal Square Root Estimate feature (FEAT_RPRES), introduced in Armv8.7. Also expose this to userspace in the ID_AA64ISAR2_EL1 feature register. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211210165432.8106-4-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: cpufeature: add HWCAP for FEAT_AFPJoey Gouly2021-12-131-0/+9
| | | | | | | | | | | | | Add a new HWCAP to detect the Alternate Floating-point Behaviour feature (FEAT_AFP), introduced in Armv8.7. Also expose this to userspace in the ID_AA64MMFR1_EL1 feature register. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211210165432.8106-2-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: Add HWCAP for self-synchronising virtual counterMarc Zyngier2021-10-191-2/+10
| | | | | | | | | | | Since userspace can make use of the CNTVSS_EL0 instruction, expose it via a HWCAP. Suggested-by: Will Deacon <will@kernel.org> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211017124225.3018098-18-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: mte: Add Memory Tagging Extension documentationVincenzo Frascino2020-09-041-0/+2
| | | | | | | | | | | | | | | | | Memory Tagging Extension (part of the ARMv8.5 Extensions) provides a mechanism to detect the sources of memory related errors which may be vulnerable to exploitation, including bounds violations, use-after-free, use-after-return, use-out-of-scope and use before initialization errors. Add Memory Tagging Extension documentation for the arm64 linux kernel support. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Co-developed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Szabolcs Nagy <szabolcs.nagy@arm.com> Cc: Will Deacon <will@kernel.org>
* arm64: Documentation: Fix broken table in generated HTMLSuzuki K Poulose2020-07-081-0/+2
| | | | | | | | | | | | | | | cpu-feature-registers.rst is missing a new line before a couple of tables listing the visible fields, causing broken tables in the HTML documentation generated by "make htmldocs". Fix this by adding the missing new line. Reported-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20200707143152.154541-1-suzuki.poulose@arm.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: Basic Branch Target Identification supportDave Martin2020-03-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the bare minimum required to expose the ARMv8.5 Branch Target Identification feature to userspace. By itself, this does _not_ automatically enable BTI for any initial executable pages mapped by execve(). This will come later, but for now it should be possible to enable BTI manually on those pages by using mprotect() from within the target process. Other arches already using the generic mman.h are already using 0x10 for arch-specific prot flags, so we use that for PROT_BTI here. For consistency, signal handler entry points in BTI guarded pages are required to be annotated as such, just like any other function. This blocks a relatively minor attack vector, but comforming userspace will have the annotations anyway, so we may as well enforce them. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* Merge branch 'for-next/rng' into for-next/coreWill Deacon2020-01-221-0/+2
|\ | | | | | | | | | | * for-next/rng: (2 commits) arm64: Use v8.5-RNG entropy for KASLR seed ...
| * arm64: Implement archrandom.h for ARMv8.5-RNGRichard Henderson2020-01-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Expose the ID_AA64ISAR0.RNDR field to userspace, as the RNG system registers are always available at EL0. Implement arch_get_random_seed_long using RNDR. Given that the TRNG is likely to be a shared resource between cores, and VMs, do not explicitly force re-seeding with RNDRRS. In order to avoid code complexity and potential issues with hetrogenous systems only provide values after cpufeature has finalized the system capabilities. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> [Modified to only function after cpufeature has finalized the system capabilities and move all the code into the header -- broonie] Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> [will: Advertise HWCAP via /proc/cpuinfo] Signed-off-by: Will Deacon <will@kernel.org>
* | arm64: cpufeature: Export matrix and other features to userspaceSteven Price2020-01-151-0/+14
|/ | | | | | | | | | | | | | Export the features introduced as part of ARMv8.6 exposed in the ID_AA64ISAR1_EL1 and ID_AA64ZFR0_EL1 registers. This introduces the Matrix features (ARMv8.2-I8MM, ARMv8.2-F64MM and ARMv8.2-F32MM) along with BFloat16 (Armv8.2-BF16), speculation invalidation (SPECRES) and Data Gathering Hint (ARMv8.0-DGH). Signed-off-by: Julien Grall <julien.grall@arm.com> [Added other features in those registers] Signed-off-by: Steven Price <steven.price@arm.com> [will: Don't advertise SPECRES to userspace] Signed-off-by: Will Deacon <will@kernel.org>
*-. Merge branches 'for-next/elf-hwcap-docs', 'for-next/smccc-conduit-cleanup', ↵Catalin Marinas2019-11-081-4/+15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'for-next/zone-dma', 'for-next/relax-icc_pmr_el1-sync', 'for-next/double-page-fault', 'for-next/misc', 'for-next/kselftest-arm64-signal' and 'for-next/kaslr-diagnostics' into for-next/core * for-next/elf-hwcap-docs: : Update the arm64 ELF HWCAP documentation docs/arm64: cpu-feature-registers: Rewrite bitfields that don't follow [e, s] docs/arm64: cpu-feature-registers: Documents missing visible fields docs/arm64: elf_hwcaps: Document HWCAP_SB docs/arm64: elf_hwcaps: sort the HWCAP{, 2} documentation by ascending value * for-next/smccc-conduit-cleanup: : SMC calling convention conduit clean-up firmware: arm_sdei: use common SMCCC_CONDUIT_* firmware/psci: use common SMCCC_CONDUIT_* arm: spectre-v2: use arm_smccc_1_1_get_conduit() arm64: errata: use arm_smccc_1_1_get_conduit() arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit() * for-next/zone-dma: : Reintroduction of ZONE_DMA for Raspberry Pi 4 support arm64: mm: reserve CMA and crashkernel in ZONE_DMA32 dma/direct: turn ARCH_ZONE_DMA_BITS into a variable arm64: Make arm64_dma32_phys_limit static arm64: mm: Fix unused variable warning in zone_sizes_init mm: refresh ZONE_DMA and ZONE_DMA32 comments in 'enum zone_type' arm64: use both ZONE_DMA and ZONE_DMA32 arm64: rename variables used to calculate ZONE_DMA32's size arm64: mm: use arm64_dma_phys_limit instead of calling max_zone_dma_phys() * for-next/relax-icc_pmr_el1-sync: : Relax ICC_PMR_EL1 (GICv3) accesses when ICC_CTLR_EL1.PMHE is clear arm64: Document ICC_CTLR_EL3.PMHE setting requirements arm64: Relax ICC_PMR_EL1 accesses when ICC_CTLR_EL1.PMHE is clear * for-next/double-page-fault: : Avoid a double page fault in __copy_from_user_inatomic() if hw does not support auto Access Flag mm: fix double page fault on arm64 if PTE_AF is cleared x86/mm: implement arch_faults_on_old_pte() stub on x86 arm64: mm: implement arch_faults_on_old_pte() on arm64 arm64: cpufeature: introduce helper cpu_has_hw_af() * for-next/misc: : Various fixes and clean-ups arm64: kpti: Add NVIDIA's Carmel core to the KPTI whitelist arm64: mm: Remove MAX_USER_VA_BITS definition arm64: mm: simplify the page end calculation in __create_pgd_mapping() arm64: print additional fault message when executing non-exec memory arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill() arm64: pgtable: Correct typo in comment arm64: docs: cpu-feature-registers: Document ID_AA64PFR1_EL1 arm64: cpufeature: Fix typos in comment arm64/mm: Poison initmem while freeing with free_reserved_area() arm64: use generic free_initrd_mem() arm64: simplify syscall wrapper ifdeffery * for-next/kselftest-arm64-signal: : arm64-specific kselftest support with signal-related test-cases kselftest: arm64: fake_sigreturn_misaligned_sp kselftest: arm64: fake_sigreturn_bad_size kselftest: arm64: fake_sigreturn_duplicated_fpsimd kselftest: arm64: fake_sigreturn_missing_fpsimd kselftest: arm64: fake_sigreturn_bad_size_for_magic0 kselftest: arm64: fake_sigreturn_bad_magic kselftest: arm64: add helper get_current_context kselftest: arm64: extend test_init functionalities kselftest: arm64: mangle_pstate_invalid_mode_el[123][ht] kselftest: arm64: mangle_pstate_invalid_daif_bits kselftest: arm64: mangle_pstate_invalid_compat_toggle and common utils kselftest: arm64: extend toplevel skeleton Makefile * for-next/kaslr-diagnostics: : Provide diagnostics on boot for KASLR arm64: kaslr: Check command line before looking for a seed arm64: kaslr: Announce KASLR status on boot
| | * arm64: docs: cpu-feature-registers: Document ID_AA64PFR1_EL1Dave Martin2019-10-251-4/+11
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | Commit d71be2b6c0e1 ("arm64: cpufeature: Detect SSBS and advertise to userspace") exposes ID_AA64PFR1_EL1 to userspace, but didn't update the documentation to match. Add it. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * docs/arm64: cpu-feature-registers: Rewrite bitfields that don't follow [e, s]Julien Grall2019-11-011-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | Commit "docs/arm64: cpu-feature-registers: Documents missing visible fields" added bitfields following the convention [s, e]. However, the documentation is following [s, e] and so does the Arm ARM. Rewrite the bitfields to match the format [s, e]. Fixes: a8613e7070e7 ("docs/arm64: cpu-feature-registers: Documents missing visible fields") Signed-off-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * docs/arm64: cpu-feature-registers: Documents missing visible fieldsJulien Grall2019-10-141-0/+4
|/ | | | | | | | | A couple of fields visible to userspace are not described in the documentation. So update it. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* docs: arm64: convert docs to ReST and rename to .rstMauro Carvalho Chehab2019-06-141-0/+304
The documentation is in a format that is very close to ReST format. The conversion is actually: - add blank lines in order to identify paragraphs; - fixing tables markups; - adding some lists markups; - marking literal blocks; - adjust some title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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