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2025-07-09vdso/vsyscall: Split up __arch_update_vsyscall() into __arch_update_vdso_clock()Thomas Weißschuh
The upcoming auxiliary clocks need this hook, too. To separate the architecture hooks from the timekeeper internals, refactor the hook to only operate on a single vDSO clock. While at it, use a more robust #define for the hook override. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-3-df7d9f87b9b8@linutronix.de
2025-05-28Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The headline feature is the re-enablement of support for Arm's Scalable Matrix Extension (SME) thanks to a bumper crop of fixes from Mark Rutland. If matrices aren't your thing, then Ryan's page-table optimisation work is much more interesting. Summary: ACPI, EFI and PSCI: - Decouple Arm's "Software Delegated Exception Interface" (SDEI) support from the ACPI GHES code so that it can be used by platforms booted with device-tree - Remove unnecessary per-CPU tracking of the FPSIMD state across EFI runtime calls - Fix a node refcount imbalance in the PSCI device-tree code CPU Features: - Ensure register sanitisation is applied to fields in ID_AA64MMFR4 - Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM guests can reliably query the underlying CPU types from the VMM - Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes to our context-switching, signal handling and ptrace code Entry code: - Hook up TIF_NEED_RESCHED_LAZY so that CONFIG_PREEMPT_LAZY can be selected Memory management: - Prevent BSS exports from being used by the early PI code - Propagate level and stride information to the low-level TLB invalidation routines when operating on hugetlb entries - Use the page-table contiguous hint for vmap() mappings with VM_ALLOW_HUGE_VMAP where possible - Optimise vmalloc()/vmap() page-table updates to use "lazy MMU mode" and hook this up on arm64 so that the trailing DSB (used to publish the updates to the hardware walker) can be deferred until the end of the mapping operation - Extend mmap() randomisation for 52-bit virtual addresses (on par with 48-bit addressing) and remove limited support for randomisation of the linear map Perf and PMUs: - Add support for probing the CMN-S3 driver using ACPI - Minor driver fixes to the CMN, Arm-NI and amlogic PMU drivers Selftests: - Fix FPSIMD and SME tests to align with the freshly re-enabled SME support - Fix default setting of the OUTPUT variable so that tests are installed in the right location vDSO: - Replace raw counter access from inline assembly code with a call to the the __arch_counter_get_cntvct() helper function Miscellaneous: - Add some missing header inclusions to the CCA headers - Rework rendering of /proc/cpuinfo to follow the x86-approach and avoid repeated buffer expansion (the user-visible format remains identical) - Remove redundant selection of CONFIG_CRC32 - Extend early error message when failing to map the device-tree blob" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (83 commits) arm64: cputype: Add cputype definition for HIP12 arm64: el2_setup.h: Make __init_el2_fgt labels consistent, again perf/arm-cmn: Add CMN S3 ACPI binding arm64/boot: Disallow BSS exports to startup code arm64/boot: Move global CPU override variables out of BSS arm64/boot: Move init_pgdir[] and init_idmap_pgdir[] into __pi_ namespace perf/arm-cmn: Initialise cmn->cpu earlier kselftest/arm64: Set default OUTPUT path when undefined arm64: Update comment regarding values in __boot_cpu_mode arm64: mm: Drop redundant check in pmd_trans_huge() arm64/mm: Re-organise setting up FEAT_S1PIE registers PIRE0_EL1 and PIR_EL1 arm64/mm: Permit lazy_mmu_mode to be nested arm64/mm: Disable barrier batching in interrupt contexts arm64/cpuinfo: only show one cpu's info in c_show() arm64/mm: Batch barriers when updating kernel mappings mm/vmalloc: Enter lazy mmu mode while manipulating vmalloc ptes arm64/mm: Support huge pte-mapped pages in vmap mm/vmalloc: Gracefully unmap huge ptes mm/vmalloc: Warn on improper use of vunmap_range() arm64/mm: Hoist barriers out of set_ptes_anysz() loop ...
2025-05-02arm64: vdso: Work around invalid absolute relocations from GCCThomas Weißschuh
All vDSO code needs to be completely position independent. Symbol references are marked as hidden so the compiler emits PC-relative relocations. However GCC emits absolute relocations for symbol-relative references with an offset >= 64KiB. After recent refactorings in the vDSO code this is the case in __arch_get_vdso_u_timens_data() with a page size of 64KiB. Work around the issue by preventing the optimizer from seeing the offsets. Fixes: 83a2a6b8cfc5 ("vdso/gettimeofday: Prepare do_hres_timens() for introduction of struct vdso_clock") Reported-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/all/20250430-vdso-absolute-reloc-v2-1-5efcc3bc4b26@linutronix.de Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120002 Closes: https://lore.kernel.org/lkml/aApGPAoctq_eoE2g@t14ultra/
2025-04-29arm64: vdso: Use __arch_counter_get_cntvct()Breno Leitao
While reading how `cntvct_el0` was read in the kernel, I found that __arch_get_hw_counter() is doing something very similar to what __arch_counter_get_cntvct() is already doing. Use the existing __arch_counter_get_cntvct() function instead of duplicating similar inline assembly code in __arch_get_hw_counter(). Both functions were performing nearly identical operations to read the cntvct_el0 register. The only difference was that __arch_get_hw_counter() included a memory clobber in its inline assembly, which appears unnecessary in this context. This change simplifies the code by eliminating duplicate functionality and improves maintainability by centralizing the counter access logic in a single implementation. Signed-off-by: Breno Leitao <leitao@debian.org> Link: https://lore.kernel.org/r/20250407-arm-vdso-v1-1-7012de25b195@debian.org Signed-off-by: Will Deacon <will@kernel.org>
2025-03-08vdso: Rework struct vdso_time_data and introduce struct vdso_clockAnna-Maria Behnsen
To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be an array of VDSO clocks. Now that all preparatory changes are in place: Split the clock related struct members into a separate struct vdso_clock. Make sure all users are aware, that vdso_time_data is no longer initialized as an array and vdso_clock is now the array inside vdso_data. Remove the vdso_clock define, which mapped it to vdso_time_data for the transition. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-19-c1b5c69a166f@linutronix.de
2025-03-08arm64/vdso: Prepare introduction of struct vdso_clockNam Cao
To support multiple PTP clocks, the VDSO data structure needs to be reworked. All clock specific data will end up in struct vdso_clock and in struct vdso_time_data there will be array of VDSO clocks. At the moment, vdso_clock is simply a define which maps vdso_clock to vdso_time_data. To prepare for the rework of the data structures, replace the struct vdso_time_data pointer with a struct vdso_clock pointer where applicable. No functional change. Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-16-c1b5c69a166f@linutronix.de
2025-02-21arm64: vdso: Switch to generic storage implementationThomas Weißschuh
The generic storage implementation provides the same features as the custom one. However it can be shared between architectures, making maintenance easier. This switch also moves the random state data out of the time data page. The currently used hardcoded __VDSO_RND_DATA_OFFSET does not take into account changes to the time data page layout. Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-8-13a4669dfc8c@linutronix.de
2024-10-15vdso: Remove timekeeper argument of __arch_update_vsyscall()Thomas Weißschuh
No implementation of this hook uses the passed in timekeeper anymore. This avoids including a non-VDSO header while building the VDSO, which can lead to compilation errors. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/all/20241010-vdso-generic-arch_update_vsyscall-v1-1-7fe5a3ea4382@linutronix.de
2024-09-13arm64: vDSO: Wire up getrandom() vDSO implementationAdhemerval Zanella
Hook up the generic vDSO implementation to the aarch64 vDSO data page. The _vdso_rng_data required data is placed within the _vdso_data vvar page, by using a offset larger than the vdso_data. The vDSO function requires a ChaCha20 implementation that does not write to the stack, and that can do an entire ChaCha20 permutation. The one provided uses NEON on the permute operation, with a fallback to the syscall for chips that do not support AdvSIMD. This also passes the vdso_test_chacha test along with vdso_test_getrandom. The vdso_test_getrandom bench-single result on Neoverse-N1 shows: vdso: 25000000 times in 0.783884250 seconds libc: 25000000 times in 8.780275399 seconds syscall: 25000000 times in 8.786581518 seconds A small fixup to arch/arm64/include/asm/mman.h was required to avoid pulling kernel code into the vDSO, similar to what's already done in arch/arm64/include/asm/rwonce.h. Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2024-07-10arm64: rework compat syscall macrosArnd Bergmann
The generated asm/unistd_compat_32.h header file now contains macros that can be used directly in the vdso and the signal trampolines, so remove the duplicate definitions. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-09-09arm64: vdso: use SYS_CNTVCTSS_EL0 for gettimeofdayJoey Gouly
If FEAT_ECV is implemented, the self-synchronized counter CNTVCTSS_EL0 can be used, removing the need for an ISB. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20220830104833.34636-4-joey.gouly@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-10-21arm64: vdso32: drop test for -march=armv8-aNick Desaulniers
As Arnd points out: gcc-4.8 already supported -march=armv8, and we require gcc-5.1 now, so both this #if/#else construct and the corresponding "cc32-option,-march=armv8-a" check should be obsolete now. Link: https://lore.kernel.org/lkml/CAK8P3a3UBEJ0Py2ycz=rHfgog8g3mCOeQOwO0Gmp-iz6Uxkapg@mail.gmail.com/ Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20211019223646.1146945-3-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
2021-10-21arm64: vdso32: drop the test for dmb ishldNick Desaulniers
Binutils added support for this instruction in commit e797f7e0b2bedc9328d4a9a0ebc63ca7a2dbbebc which shipped in 2.24 (just missing the 2.23 release) but was cherry-picked into 2.23 in commit 27a50d6755bae906bc73b4ec1a8b448467f0bea1. Thanks to Christian and Simon for helping me with the patch archaeology. According to Documentation/process/changes.rst, the minimum supported version of binutils is 2.23. Since all supported versions of GAS support this instruction, drop the assembler invocation, preprocessor flags/guards, and the cross assembler macro that's now unused. This also avoids a recursive self reference in a follow up cleanup patch. Cc: Christian Biesinger <cbiesinger@google.com> Cc: Simon Marchi <simon.marchi@polymtl.ca> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20211019223646.1146945-2-ndesaulniers@google.com Signed-off-by: Will Deacon <will@kernel.org>
2021-04-30Merge tag 'powerpc-5.13-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable KFENCE for 32-bit. - Implement EBPF for 32-bit. - Convert 32-bit to do interrupt entry/exit in C. - Convert 64-bit BookE to do interrupt entry/exit in C. - Changes to our signal handling code to use user_access_begin/end() more extensively. - Add support for time namespaces (CONFIG_TIME_NS) - A series of fixes that allow us to reenable STRICT_KERNEL_RWX. - Other smaller features, fixes & cleanups. Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior, Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, and Zhang Yunkai. * tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits) powerpc/signal32: Fix erroneous SIGSEGV on RT signal return powerpc: Avoid clang uninitialized warning in __get_user_size_allowed powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n powerpc/kasan: Fix shadow start address with modules powerpc/kernel/iommu: Use largepool as a last resort when !largealloc powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants" powerpc/iommu: Annotate nested lock for lockdep powerpc/iommu: Do not immediately panic when failed IOMMU table allocation powerpc/iommu: Allocate it_map by vmalloc selftests/powerpc: remove unneeded semicolon powerpc/64s: remove unneeded semicolon powerpc/eeh: remove unneeded semicolon powerpc/selftests: Add selftest to test concurrent perf/ptrace events powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR powerpc/selftests/perf-hwbreak: Coalesce event creation code powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR powerpc/configs: Add IBMVNIC to some 64-bit configs selftests/powerpc: Add uaccess flush test ...
2021-04-14lib/vdso: Add vdso_data pointer as input to __arch_get_timens_vdso_data()Christophe Leroy
For the same reason as commit e876f0b69dc9 ("lib/vdso: Allow architectures to provide the vdso data pointer"), powerpc wants to avoid calculation of relative position to code. As the timens_vdso_data is next page to vdso_data, provide vdso_data pointer to __arch_get_timens_vdso_data() in order to ease the calculation on powerpc in following patches. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Acked-by: Andrei Vagin <avagin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/539c4204b1baa77c55f758904a1ea239abbc7a5c.1617209142.git.christophe.leroy@csgroup.eu
2021-03-24arm64: vdso: Avoid ISB after reading from cntvct_el0Will Deacon
We can avoid the expensive ISB instruction after reading the counter in the vDSO gettime functions by creating a fake address hazard against a dummy stack read, just like we do inside the kernel. Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lore.kernel.org/r/20210318170738.7756-5-will@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-08-06vdso/treewide: Add vdso_data pointer argument to __arch_get_hw_counter()Thomas Gleixner
MIPS already uses and S390 will need the vdso data pointer in __arch_get_hw_counter(). This works nicely as long as the architecture does not support time namespaces in the VDSO. With time namespaces enabled the regular accessor to the vdso data pointer __arch_get_vdso_data() will return the namespace specific VDSO data page for tasks which are part of a non-root time namespace. This would cause the architectures which need the vdso data pointer in __arch_get_hw_counter() to access the wrong vdso data page. Add a vdso_data pointer argument to __arch_get_hw_counter() and hand it in from the call sites in the core code. For architectures which do not need the data pointer in their counter accessor function the compiler will just optimize it out. Fix up all existing architecture implementations and make MIPS utilize the pointer instead of invoking the accessor function. No functional change and no change in the resulting object code (except MIPS). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/draft-87wo2ekuzn.fsf@nanos.tec.linutronix.de
2020-08-03Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 and cross-arch updates from Catalin Marinas: "Here's a slightly wider-spread set of updates for 5.9. Going outside the usual arch/arm64/ area is the removal of read_barrier_depends() series from Will and the MSI/IOMMU ID translation series from Lorenzo. The notable arm64 updates include ARMv8.4 TLBI range operations and translation level hint, time namespace support, and perf. Summary: - Removal of the tremendously unpopular read_barrier_depends() barrier, which is a NOP on all architectures apart from Alpha, in favour of allowing architectures to override READ_ONCE() and do whatever dance they need to do to ensure address dependencies provide LOAD -> LOAD/STORE ordering. This work also offers a potential solution if compilers are shown to convert LOAD -> LOAD address dependencies into control dependencies (e.g. under LTO), as weakly ordered architectures will effectively be able to upgrade READ_ONCE() to smp_load_acquire(). The latter case is not used yet, but will be discussed further at LPC. - Make the MSI/IOMMU input/output ID translation PCI agnostic, augment the MSI/IOMMU ACPI/OF ID mapping APIs to accept an input ID bus-specific parameter and apply the resulting changes to the device ID space provided by the Freescale FSL bus. - arm64 support for TLBI range operations and translation table level hints (part of the ARMv8.4 architecture version). - Time namespace support for arm64. - Export the virtual and physical address sizes in vmcoreinfo for makedumpfile and crash utilities. - CPU feature handling cleanups and checks for programmer errors (overlapping bit-fields). - ACPI updates for arm64: disallow AML accesses to EFI code regions and kernel memory. - perf updates for arm64. - Miscellaneous fixes and cleanups, most notably PLT counting optimisation for module loading, recordmcount fix to ignore relocations other than R_AARCH64_CALL26, CMA areas reserved for gigantic pages on 16K and 64K configurations. - Trivial typos, duplicate words" Link: http://lkml.kernel.org/r/20200710165203.31284-1-will@kernel.org Link: http://lkml.kernel.org/r/20200619082013.13661-1-lorenzo.pieralisi@arm.com * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (82 commits) arm64: use IRQ_STACK_SIZE instead of THREAD_SIZE for irq stack arm64/mm: save memory access in check_and_switch_context() fast switch path arm64: sigcontext.h: delete duplicated word arm64: ptrace.h: delete duplicated word arm64: pgtable-hwdef.h: delete duplicated words bus: fsl-mc: Add ACPI support for fsl-mc bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver of/irq: Make of_msi_map_rid() PCI bus agnostic of/irq: make of_msi_map_get_device_domain() bus agnostic dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus of/device: Add input id to of_dma_configure() of/iommu: Make of_map_rid() PCI agnostic ACPI/IORT: Add an input ID to acpi_dma_configure() ACPI/IORT: Remove useless PCI bus walk ACPI/IORT: Make iort_msi_map_rid() PCI agnostic ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC arm64: enable time namespace support arm64/vdso: Restrict splitting VVAR VMA arm64/vdso: Handle faults on timens page ...
2020-07-31Merge branch 'for-next/read-barrier-depends' into for-next/coreCatalin Marinas
* for-next/read-barrier-depends: : Allow architectures to override __READ_ONCE() arm64: Reduce the number of header files pulled into vmlinux.lds.S compiler.h: Move compiletime_assert() macros into compiler_types.h checkpatch: Remove checks relating to [smp_]read_barrier_depends() include/linux: Remove smp_read_barrier_depends() from comments tools/memory-model: Remove smp_read_barrier_depends() from informal doc Documentation/barriers/kokr: Remove references to [smp_]read_barrier_depends() Documentation/barriers: Remove references to [smp_]read_barrier_depends() locking/barriers: Remove definitions for [smp_]read_barrier_depends() alpha: Replace smp_read_barrier_depends() usage with smp_[r]mb() vhost: Remove redundant use of read_barrier_depends() barrier asm/rwonce: Don't pull <asm/barrier.h> into 'asm-generic/rwonce.h' asm/rwonce: Remove smp_read_barrier_depends() invocation alpha: Override READ_ONCE() with barriered implementation asm/rwonce: Allow __READ_ONCE to be overridden by the architecture compiler.h: Split {READ,WRITE}_ONCE definitions out into rwonce.h tools: bpf: Use local copy of headers including uapi/linux/filter.h
2020-07-24arm64/vdso: Add time namespace pageAndrei Vagin
Allocate the time namespace page among VVAR pages. Provide __arch_get_timens_vdso_data() helper for VDSO code to get the code-relative position of VVARs on that special page. If a task belongs to a time namespace then the VVAR page which contains the system wide VDSO data is replaced with a namespace specific page which has the same layout as the VVAR page. That page has vdso_data->seq set to 1 to enforce the slow path and vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time namespace handling path. The extra check in the case that vdso_data->seq is odd, e.g. a concurrent update of the VDSO data is in progress, is not really affecting regular tasks which are not part of a time namespace as the task is spin waiting for the update to finish and vdso_data->seq to become even again. If a time namespace task hits that code path, it invokes the corresponding time getter function which retrieves the real VVAR page, reads host time and then adds the offset for the requested clock which is stored in the special VVAR page. The time-namespace page isn't allocated on !CONFIG_TIME_NAMESPACE, but vma is the same size, which simplifies criu/vdso migration between different kernel configs. Signed-off-by: Andrei Vagin <avagin@gmail.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Dmitry Safonov <dima@arista.com> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20200624083321.144975-4-avagin@gmail.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-21asm/rwonce: Don't pull <asm/barrier.h> into 'asm-generic/rwonce.h'Will Deacon
Now that 'smp_read_barrier_depends()' has gone the way of the Norwegian Blue, drop the inclusion of <asm/barrier.h> in 'asm-generic/rwonce.h'. This requires fixups to some architecture vdso headers which were previously relying on 'asm/barrier.h' coming in via 'linux/compiler.h'. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-07-08arm64: Introduce a way to disable the 32bit vdsoMarc Zyngier
We have a class of errata (grouped under the ARM64_WORKAROUND_1418040 banner) that force the trapping of counter access from 32bit EL0. We would normally disable the whole vdso for such defect, except that it would disable it for 64bit userspace as well, which is a shame. Instead, add a new vdso_clock_mode, which signals that the vdso isn't usable for compat tasks. This gets checked in the new vdso_clocksource_ok() helper, now provided for the 32bit vdso. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200706163802.1836732-2-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2020-03-21arm64: vdso32: Include common headers in the vdso libraryVincenzo Frascino
The vDSO library should only include the necessary headers required for a userspace library (UAPI and a minimal set of kernel headers). To make this possible it is necessary to isolate from the kernel headers the common parts that are strictly necessary to build the library. Refactor the vdso32 implementation to include common headers. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200320145351.32292-22-vincenzo.frascino@arm.com
2020-03-21arm64: vdso: Include common headers in the vdso libraryVincenzo Frascino
The vDSO library should only include the necessary headers required for a userspace library (UAPI and a minimal set of kernel headers). To make this possible it is necessary to isolate from the kernel headers the common parts that are strictly necessary to build the library. Refactor the vdso implementation to include common headers. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200320145351.32292-21-vincenzo.frascino@arm.com
2020-03-21arm64: Introduce asm/vdso/processor.hVincenzo Frascino
The vDSO library should only include the necessary headers required for a userspace library (UAPI and a minimal set of kernel headers). To make this possible it is necessary to isolate from the kernel headers the common parts that are strictly necessary to build the library. Introduce asm/vdso/processor.h to contain all the arm64 specific functions that are suitable for vDSO inclusion. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200320145351.32292-20-vincenzo.frascino@arm.com
2020-03-21arm64: vdso32: Code clean upVincenzo Frascino
The compat vdso library had some checks that are not anymore relevant. Remove the unused code from the compat vDSO library. Note: This patch is preparatory for a future one that will introduce asm/vdso/processor.h on arm64. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/lkml/20200317122220.30393-19-vincenzo.frascino@arm.com Link: https://lkml.kernel.org/r/20200320145351.32292-19-vincenzo.frascino@arm.com
2020-03-21arm64: Introduce asm/vdso/clocksource.hVincenzo Frascino
The vDSO library should only include the necessary headers required for a userspace library (UAPI and a minimal set of kernel headers). To make this possible it is necessary to isolate from the kernel headers the common parts that are strictly necessary to build the library. Introduce asm/vdso/clocksource.h to contain all the arm64 specific functions that are suitable for vDSO inclusion. This header will be required by a future patch that will generalize vdso/clocksource.h. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/20200320145351.32292-7-vincenzo.frascino@arm.com
2020-02-17ARM/arm64: vdso: Use common vdso clock mode storageThomas Gleixner
Convert ARM/ARM64 to the generic VDSO clock mode storage. This needs to happen in one go as they share the clocksource driver. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lkml.kernel.org/r/20200207124403.363235229@linutronix.de
2020-01-14arm64: compat: vdso: Remove unused VDSO_HAS_32BIT_FALLBACKVincenzo Frascino
VDSO_HAS_32BIT_FALLBACK has been removed from the core since the architectures that support the generic vDSO library have been converted to support the 32 bit fallbacks. Remove unused VDSO_HAS_32BIT_FALLBACK from arm64 compat vdso. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20190830135902.20861-7-vincenzo.frascino@arm.com
2020-01-14arm64: compat: vdso: Expose BUILD_VDSO32Vincenzo Frascino
clock_gettime32 and clock_getres_time32 should be compiled only with the 32 bit vdso library. Expose BUILD_VDSO32 when arm64 compat is compiled, to provide an indication to the generic library to include these symbols. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20190830135902.20861-2-vincenzo.frascino@arm.com
2019-11-04timekeeping/vsyscall: Update VDSO data unconditionallyHuacai Chen
The update of the VDSO data is depending on __arch_use_vsyscall() returning True. This is a leftover from the attempt to map the features of various architectures 1:1 into generic code. The usage of __arch_use_vsyscall() in the actual vsyscall implementations got dropped and replaced by the requirement for the architecture code to return U64_MAX if the global clocksource is not usable in the VDSO. But the __arch_use_vsyscall() check in the update code stayed which causes the VDSO data to be stale or invalid when an architecture actually implements that function and returns False when the current clocksource is not usable in the VDSO. As a consequence the VDSO implementations of clock_getres(), time(), clock_gettime(CLOCK_.*_COARSE) operate on invalid data and return bogus information. Remove the __arch_use_vsyscall() check from the VDSO update function and update the VDSO data unconditionally. [ tglx: Massaged changelog and removed the now useless implementations in asm-generic/ARM64/MIPS ] Fixes: 44f57d788e7deecb50 ("timekeeping: Provide a generic update_vsyscall() implementation") Signed-off-by: Huacai Chen <chenhc@lemote.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Burton <paul.burton@mips.com> Cc: linux-mips@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1571887709-11447-1-git-send-email-chenhc@lemote.com
2019-10-07arm64: vdso32: Detect binutils support for dmb ishldVincenzo Frascino
Older versions of binutils (prior to 2.24) do not support the "ISHLD" option for memory barrier instructions, which leads to a build failure when assembling the vdso32 library. Add a compilation time mechanism that detects if binutils supports those instructions and configure the kernel accordingly. Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-07-31arm64: compat: vdso: Use legacy syscalls as fallbackThomas Gleixner
The generic VDSO implementation uses the Y2038 safe clock_gettime64() and clock_getres_time64() syscalls as fallback for 32bit VDSO. This breaks seccomp setups because these syscalls might be not (yet) allowed. Implement the 32bit variants which use the legacy syscalls and select the variant in the core library. The 64bit time variants are not removed because they are required for the time64 based vdso accessors. Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation") Reported-by: Sean Christopherson <sean.j.christopherson@intel.com> Reported-by: Paul Bolle <pebolle@tiscali.nl> Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://lkml.kernel.org/r/20190728131648.971361611@linutronix.de
2019-06-26arm64: compat: Fix __arch_get_hw_counter() implementationVincenzo Frascino
Provide the following fixes for the __arch_get_hw_counter() implementation on arm64: - Fallback on syscall when an unstable counter is detected. - Introduce isb()s before and after the counter read to avoid speculation of the counter value and of the seq lock respectively. The second isb() is a temporary solution that will be revisited in 5.3-rc1. These fixes restore the semantics that __arch_counter_get_cntvct() had on arm64. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: catalin.marinas@arm.com Cc: will.deacon@arm.com Cc: arnd@arndb.de Cc: linux@armlinux.org.uk Cc: ralf@linux-mips.org Cc: paul.burton@mips.com Cc: daniel.lezcano@linaro.org Cc: salyzyn@android.com Cc: pcc@google.com Cc: shuah@kernel.org Cc: 0x7f454c46@gmail.com Cc: linux@rasmusvillemoes.dk Cc: huw@codeweavers.com Cc: sthotton@marvell.com Cc: andre.przywara@arm.com Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190625161804.38713-3-vincenzo.frascino@arm.com
2019-06-26arm64: Fix __arch_get_hw_counter() implementationVincenzo Frascino
Provide the following fixes for the __arch_get_hw_counter() implementation on arm64: - Fallback on syscall when an unstable counter is detected. - Introduce isb()s before and after the counter read to avoid speculation of the counter value and of the seq lock respectively. The second isb() is a temporary solution that will be revisited in 5.3-rc1. These fixes restore the semantics that __arch_counter_get_cntvct() had on arm64. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: catalin.marinas@arm.com Cc: will.deacon@arm.com Cc: arnd@arndb.de Cc: linux@armlinux.org.uk Cc: ralf@linux-mips.org Cc: paul.burton@mips.com Cc: daniel.lezcano@linaro.org Cc: salyzyn@android.com Cc: pcc@google.com Cc: shuah@kernel.org Cc: 0x7f454c46@gmail.com Cc: linux@rasmusvillemoes.dk Cc: huw@codeweavers.com Cc: sthotton@marvell.com Cc: andre.przywara@arm.com Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20190625161804.38713-2-vincenzo.frascino@arm.com
2019-06-26arm64: compat: No need for pre-ARMv7 barriers on an ARMv8 systemCatalin Marinas
Remove the deprecated (pre-ARMv7) compat barriers as they would not be used on an ARMv8 system. Fixes: a7f71a2c8903 ("arm64: compat: Add vDSO") Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@armlinux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Salyzyn <salyzyn@android.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Huw Davies <huw@codeweavers.com> Cc: Shijith Thotton <sthotton@marvell.com> Cc: Andre Przywara <andre.przywara@arm.com> Link: https://lkml.kernel.org/r/20190624140018.GD29120@arrakis.emea.arm.com
2019-06-22arm64: compat: Add vDSOVincenzo Frascino
Provide the arm64 compat (AArch32) vDSO in kernel/vdso32 in a similar way to what happens in kernel/vdso. The compat vDSO leverages on an adaptation of the arm architecture code with few changes: - Use of lib/vdso for gettimeofday - Implement a syscall based fallback - Introduce clock_getres() for the compat library - Implement trampolines - Implement elf note To build the compat vDSO a 32 bit compiler is required and needs to be specified via CONFIG_CROSS_COMPILE_COMPAT_VDSO. The code is not yet enabled as other prerequisites are missing. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shijith Thotton <sthotton@marvell.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@armlinux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Salyzyn <salyzyn@android.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Huw Davies <huw@codeweavers.com> Link: https://lkml.kernel.org/r/20190621095252.32307-11-vincenzo.frascino@arm.com
2019-06-22arm64: vdso: Substitute gettimeofday() with C implementationVincenzo Frascino
To take advantage of the commonly defined vdso interface for gettimeofday() the architectural code requires an adaptation. Re-implement the gettimeofday VDSO in C in order to use lib/vdso. With the new implementation arm64 gains support for CLOCK_BOOTTIME and CLOCK_TAI. [ tglx: Reformatted the function line breaks ] Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shijith Thotton <sthotton@marvell.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@armlinux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Salyzyn <salyzyn@android.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Huw Davies <huw@codeweavers.com> Link: https://lkml.kernel.org/r/20190621095252.32307-5-vincenzo.frascino@arm.com