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2024-07-29Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linuxLinus Torvalds
Pull ARM updates from Russell King: - ftrace: don't assume stack frames are contiguous in memory - remove unused mod_inwind_map structure - spelling fixes - allow use of LD dead code/data elimination - fix callchain_trace() return value - add support for stackleak gcc plugin - correct some reset asm function prototypes for CFI [ Missed the merge window because Russell forgot to push out ] * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux: ARM: 9408/1: mm: CFI: Fix some erroneous reset prototypes ARM: 9407/1: Add support for STACKLEAK gcc plugin ARM: 9406/1: Fix callchain_trace() return value ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION ARM: 9403/1: Alpine: Spelling s/initialiing/initializing/ ARM: 9402/1: Kconfig: Spelling s/Cortex A-/Cortex-A/ ARM: 9400/1: Remove unused struct 'mod_unwind_map'
2024-07-27Merge tag 'riscv-for-linus-6.11-mw2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - Support for NUMA (via SRAT and SLIT), console output (via SPCR), and cache info (via PPTT) on ACPI-based systems. - The trap entry/exit code no longer breaks the return address stack predictor on many systems, which results in an improvement to trap latency. - Support for HAVE_ARCH_STACKLEAK. - The sv39 linear map has been extended to support 128GiB mappings. - The frequency of the mtime CSR is now visible via hwprobe. * tag 'riscv-for-linus-6.11-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (21 commits) RISC-V: Provide the frequency of time CSR via hwprobe riscv: Extend sv39 linear mapping max size to 128G riscv: enable HAVE_ARCH_STACKLEAK riscv: signal: Remove unlikely() from WARN_ON() condition riscv: Improve exception and system call latency RISC-V: Select ACPI PPTT drivers riscv: cacheinfo: initialize cacheinfo's level and type from ACPI PPTT riscv: cacheinfo: remove the useless input parameter (node) of ci_leaf_init() RISC-V: ACPI: Enable SPCR table for console output on RISC-V riscv: boot: remove duplicated targets line trace: riscv: Remove deprecated kprobe on ftrace support riscv: cpufeature: Extract common elements from extension checking riscv: Introduce vendor variants of extension helpers riscv: Add vendor extensions to /proc/cpuinfo riscv: Extend cpufeature.c to detect vendor extensions RISC-V: run savedefconfig for defconfig RISC-V: hwprobe: sort EXT_KEY()s in hwprobe_isa_ext0() alphabetically ACPI: NUMA: replace pr_info with pr_debug in arch_acpi_numa_init ACPI: NUMA: change the ACPI_NUMA to a hidden option ACPI: NUMA: Add handler for SRAT RINTC affinity structure ...
2024-07-26riscv: enable HAVE_ARCH_STACKLEAKJisheng Zhang
Add support for the stackleak feature. Whenever the kernel returns to user space the kernel stack is filled with a poison value. At the same time, disables the plugin in EFI stub code because EFI stub is out of scope for the protection. Tested on qemu and milkv duo: / # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT [ 38.675575] lkdtm: Performing direct entry STACKLEAK_ERASING [ 38.678448] lkdtm: stackleak stack usage: [ 38.678448] high offset: 288 bytes [ 38.678448] current: 496 bytes [ 38.678448] lowest: 1328 bytes [ 38.678448] tracked: 1328 bytes [ 38.678448] untracked: 448 bytes [ 38.678448] poisoned: 14312 bytes [ 38.678448] low offset: 8 bytes [ 38.689887] lkdtm: OK: the rest of the thread stack is properly erased Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240623235316.2010-1-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-25Merge tag 'efi-fixes-for-v6.11-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fixes from Ard Biesheuvel: - Wipe screen_info after allocating it from the heap - used by arm32 and EFI zboot, other EFI architectures allocate it statically - Revert to allocating boot_params from the heap on x86 when entering via the native PE entrypoint, to work around a regression on older Dell hardware * tag 'efi-fixes-for-v6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: x86/efistub: Revert to heap allocated boot_params for PE entrypoint efi/libstub: Zero initialize heap allocated struct screen_info
2024-07-22Merge tag 'loongarch-6.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Define __ARCH_WANT_NEW_STAT in unistd.h - Always enumerate MADT and setup logical-physical CPU mapping - Add irq_work support via self IPIs - Add RANDOMIZE_KSTACK_OFFSET support - Add ARCH_HAS_PTE_DEVMAP support - Add ARCH_HAS_DEBUG_VM_PGTABLE support - Add writecombine support for DMW-based ioremap() - Add architectural preparation for CPUFreq - Add ACPI standard hardware register based S3 support - Add support for relocating the kernel with RELR relocation - Some bug fixes and other small changes * tag 'loongarch-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: LoongArch: Make the users of larch_insn_gen_break() constant LoongArch: Check TIF_LOAD_WATCH to enable user space watchpoint LoongArch: Use rustc option -Zdirect-access-external-data LoongArch: Add support for relocating the kernel with RELR relocation LoongArch: Remove a redundant checking in relocator LoongArch: Use correct API to map cmdline in relocate_kernel() LoongArch: Automatically disable KASLR for hibernation LoongArch: Add ACPI standard hardware register based S3 support LoongArch: Add architectural preparation for CPUFreq LoongArch: Add writecombine support for DMW-based ioremap() LoongArch: Add ARCH_HAS_DEBUG_VM_PGTABLE support LoongArch: Add ARCH_HAS_PTE_DEVMAP support LoongArch: Add RANDOMIZE_KSTACK_OFFSET support LoongArch: Add irq_work support via self IPIs LoongArch: Always enumerate MADT and setup logical-physical CPU mapping LoongArch: Define __ARCH_WANT_NEW_STAT in unistd.h
2024-07-20Merge tag 'riscv-for-linus-6.11-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for various new ISA extensions: * The Zve32[xf] and Zve64[xfd] sub-extensios of the vector extension * Zimop and Zcmop for may-be-operations * The Zca, Zcf, Zcd and Zcb sub-extensions of the C extension * Zawrs - riscv,cpu-intc is now dtschema - A handful of performance improvements and cleanups to text patching - Support for memory hot{,un}plug - The highest user-allocatable virtual address is now visible in hwprobe * tag 'riscv-for-linus-6.11-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (58 commits) riscv: lib: relax assembly constraints in hweight riscv: set trap vector earlier KVM: riscv: selftests: Add Zawrs extension to get-reg-list test KVM: riscv: Support guest wrs.nto riscv: hwprobe: export Zawrs ISA extension riscv: Add Zawrs support for spinlocks dt-bindings: riscv: Add Zawrs ISA extension description riscv: Provide a definition for 'pause' riscv: hwprobe: export highest virtual userspace address riscv: Improve sbi_ecall() code generation by reordering arguments riscv: Add tracepoints for SBI calls and returns riscv: Optimize crc32 with Zbc extension riscv: Enable DAX VMEMMAP optimization riscv: mm: Add support for ZONE_DEVICE virtio-mem: Enable virtio-mem for RISC-V riscv: Enable memory hotplugging for RISC-V riscv: mm: Take memory hotplug read-lock during kernel page table dump riscv: mm: Add memory hotplugging support riscv: mm: Add pfn_to_kaddr() implementation riscv: mm: Refactor create_linear_mapping_range() for memory hot add ...
2024-07-20LoongArch: Add writecombine support for DMW-based ioremap()Huacai Chen
Currently, only TLB-based ioremap() support writecombine, so add the counterpart for DMW-based ioremap() with help of DMW2. The base address (WRITECOMBINE_BASE) is configured as 0xa000000000000000. DMW3 is unused by kernel now, however firmware may leave garbage in them and interfere kernel's address mapping. So clear it as necessary. BTW, centralize the DMW configuration to macro SETUP_DMWINS. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-07-18x86/efistub: Revert to heap allocated boot_params for PE entrypointArd Biesheuvel
This is a partial revert of commit 8117961d98f ("x86/efi: Disregard setup header of loaded image") which triggers boot issues on older Dell laptops. As it turns out, switching back to a heap allocation for the struct boot_params constructed by the EFI stub works around this, even though it is unclear why. Cc: Christian Heusel <christian@heusel.eu> Reported-by: <mavrix#kernel@simplelogin.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-17efi/libstub: Zero initialize heap allocated struct screen_infoQiang Ma
After calling uefi interface allocate_pool to apply for memory, we should clear 0 to prevent the possibility of using random values. Signed-off-by: Qiang Ma <maqianga@uniontech.com> Cc: <stable@vger.kernel.org> # v6.6+ Fixes: 732ea9db9d8a ("efi: libstub: Move screen_info handling to common code") Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-12efi: Replace efi_memory_attributes_table_t 0-sized array with flexible arrayKees Cook
While efi_memory_attributes_table_t::entry isn't used directly as an array, it is used as a base for pointer arithmetic. The type is wrong as it's not technically an array of efi_memory_desc_t's; they could be larger. Regardless, leave the type unchanged and remove the old style "0" array size. Additionally replace the open-coded entry offset code with the existing efi_memdesc_ptr() helper. Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-12efi: Rename efi_early_memdesc_ptr() to efi_memdesc_ptr()Kees Cook
The "early" part of the helper's name isn't accurate[1]. Drop it in preparation for adding a new (not early) usage. Suggested-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/lkml/CAMj1kXEyDjH0uu3Z4eBesV3PEnKGi5ArXXMp7R-hn8HdRytiPg@mail.gmail.com [1] Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-10arm64/efistub: Clean up KASLR logicArd Biesheuvel
Clean up some redundant code in the KASLR placement handling logic. No functional change intended. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08x86/efistub: Drop redundant clearing of BSSArd Biesheuvel
As it turns out, clearing the BSS was not the right fix for the issue that was ultimately fixed by commit decd347c2a75 ("x86/efistub: Reinstate soft limit for initrd loading"), and given that the Windows EFI loader becomes very unhappy when entered with garbage in BSS, this is one thing that x86 PC EFI implementations can be expected to get right. So drop it from the pure PE entrypoint. The handover protocol entrypoint still needs this - it is used by the flaky distro bootloaders that barely implement PE/COFF at all. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08x86/efistub: Avoid returning EFI_SUCCESS on errorArd Biesheuvel
The fail label is only used in a situation where the previous EFI API call succeeded, and so status will be set to EFI_SUCCESS. Fix this, by dropping the goto entirely, and call efi_exit() with the correct error code. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08x86/efistub: Call Apple set_os protocol on dual GPU Intel MacsAditya Garg
0c18184de990 ("platform/x86: apple-gmux: support MMIO gmux on T2 Macs") brought support for T2 Macs in apple-gmux. But in order to use dual GPU, the integrated GPU has to be enabled. On such dual GPU EFI Macs, the EFI stub needs to report that it is booting macOS in order to prevent the firmware from disabling the iGPU. This patch is also applicable for some non T2 Intel Macs. Based on this patch for GRUB by Andreas Heider <andreas@heider.io>: https://lists.gnu.org/archive/html/grub-devel/2013-12/msg00442.html Credits also goto Kerem Karabay <kekrby@gmail.com> for helping porting the patch to the Linux kernel. Cc: Orlando Chamberlain <orlandoch.dev@gmail.com> Signed-off-by: Aditya Garg <gargaditya08@live.com> [ardb: limit scope using list of DMI matches provided by Lukas and Orlando] Reviewed-by: Lukas Wunner <lukas@wunner.de> Tested-by: Aditya Garg <gargaditya08@live.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08x86/efistub: Enable SMBIOS protocol handling for x86Ard Biesheuvel
The smbios.c source file is not currently included in the x86 build, and before we can do so, it needs some tweaks to build correctly in combination with the EFI mixed mode support. Reviewed-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-02ARM: 9407/1: Add support for STACKLEAK gcc pluginJinjie Ruan
Add the STACKLEAK gcc plugin to arm32 by adding the helper used by stackleak common code: on_thread_stack(). It initialize the stack with the poison value before returning from system calls which improves the kernel security. Additionally, this disables the plugin in EFI stub code and decompress code, which are out of scope for the protection. Before the test on Qemu versatilepb board: # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT lkdtm: Performing direct entry STACKLEAK_ERASING lkdtm: XFAIL: stackleak is not supported on this arch (HAVE_ARCH_STACKLEAK=n) After: # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT lkdtm: Performing direct entry STACKLEAK_ERASING lkdtm: stackleak stack usage: high offset: 80 bytes current: 280 bytes lowest: 696 bytes tracked: 696 bytes untracked: 192 bytes poisoned: 7220 bytes low offset: 4 bytes lkdtm: OK: the rest of the thread stack is properly erased Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-07-02efistub/smbios: Simplify SMBIOS enumeration APIArd Biesheuvel
Update the efi_get_smbios_string() macro to take a pointer to the entire record struct rather than the header. This removes the need to pass the type explicitly, as it can be inferred from the typed pointer. Also, drop 'type' from the prototype of __efi_get_smbios_string(), as it is never referenced. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-02x86/efi: Drop support for fake EFI memory mapsArd Biesheuvel
Between kexec and confidential VM support, handling the EFI memory maps correctly on x86 is already proving to be rather difficult (as opposed to other EFI architectures which manage to never modify the EFI memory map to begin with) EFI fake memory map support is essentially a development hack (for testing new support for the 'special purpose' and 'more reliable' EFI memory attributes) that leaked into production code. The regions marked in this manner are not actually recognized as such by the firmware itself or the EFI stub (and never have), and marking memory as 'more reliable' seems rather futile if the underlying memory is just ordinary RAM. Marking memory as 'special purpose' in this way is also dubious, but may be in use in production code nonetheless. However, the same should be achievable by using the memmap= command line option with the ! operator. EFI fake memmap support is not enabled by any of the major distros (Debian, Fedora, SUSE, Ubuntu) and does not exist on other architectures, so let's drop support for it. Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-06-26riscv: dmi: Add SMBIOS/DMI supportHaibo Xu
Enable the dmi driver for riscv which would allow access the SMBIOS info through some userspace file(/sys/firmware/dmi/*). The change was based on that of arm64 and has been verified by dmidecode tool. Signed-off-by: Haibo Xu <haibo1.xu@intel.com> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Link: https://lore.kernel.org/r/20240613065507.287577-1-haibo1.xu@intel.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-06-18Merge tag 'efi-fixes-for-v6.10-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fixes from Ard Biesheuvel: "Another small set of EFI fixes. Only the x86 one is likely to affect any actual users (and has a cc:stable), but the issue it fixes was only observed in an unusual context (kexec in a confidential VM). - Ensure that EFI runtime services are not unmapped by PAN on ARM - Avoid freeing the memory holding the EFI memory map inadvertently on x86 - Avoid a false positive kmemleak warning on arm64" * tag 'efi-fixes-for-v6.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi/arm64: Fix kmemleak false positive in arm64_efi_rt_init() efi/x86: Free EFI memory map only when installing a new one. efi/arm: Disable LPAE PAN when calling EFI runtime services
2024-06-15efi/x86: Free EFI memory map only when installing a new one.Ard Biesheuvel
The logic in __efi_memmap_init() is shared between two different execution flows: - mapping the EFI memory map early or late into the kernel VA space, so that its entries can be accessed; - the x86 specific cloning of the EFI memory map in order to insert new entries that are created as a result of making a memory reservation via a call to efi_mem_reserve(). In the former case, the underlying memory containing the kernel's view of the EFI memory map (which may be heavily modified by the kernel itself on x86) is not modified at all, and the only thing that changes is the virtual mapping of this memory, which is different between early and late boot. In the latter case, an entirely new allocation is created that carries a new, updated version of the kernel's view of the EFI memory map. When installing this new version, the old version will no longer be referenced, and if the memory was allocated by the kernel, it will leak unless it gets freed. The logic that implements this freeing currently lives on the code path that is shared between these two use cases, but it should only apply to the latter. So move it to the correct spot. While at it, drop the dummy definition for non-x86 architectures, as that is no longer needed. Cc: <stable@vger.kernel.org> Fixes: f0ef6523475f ("efi: Fix efi_memmap_alloc() leaks") Tested-by: Ashish Kalra <Ashish.Kalra@amd.com> Link: https://lore.kernel.org/all/36ad5079-4326-45ed-85f6-928ff76483d3@amd.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-06-10ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATIONYuntao Liu
The current arm32 architecture does not yet support the HAVE_LD_DEAD_CODE_DATA_ELIMINATION feature. arm32 is widely used in embedded scenarios, and enabling this feature would be beneficial for reducing the size of the kernel image. In order to make this work, we keep the necessary tables by annotating them with KEEP, also it requires further changes to linker script to KEEP some tables and wildcard compiler generated sections into the right place. When using ld.lld for linking, KEEP is not recognized within the OVERLAY command, and Ard proposed a concise method to solve this problem. It boots normally with defconfig, vexpress_defconfig and tinyconfig. The size comparison of zImage is as follows: defconfig vexpress_defconfig tinyconfig 5137712 5138024 424192 no dce 5032560 4997824 298384 dce 2.0% 2.7% 29.7% shrink When using smaller config file, there is a significant reduction in the size of the zImage. We also tested this patch on a commercially available single-board computer, and the comparison is as follows: a15eb_config 2161384 no dce 2092240 dce 3.2% shrink The zImage size has been reduced by approximately 3.2%, which is 70KB on 2.1M. Signed-off-by: Yuntao Liu <liuyuntao12@huawei.com> Tested-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-06-06Merge tag 'efi-fixes-for-v6.10-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fixes from Ard Biesheuvel: - Ensure that .discard sections are really discarded in the EFI zboot image build - Return proper error numbers from efi-pstore - Add __nocfi annotations to EFI runtime wrappers * tag 'efi-fixes-for-v6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi: Add missing __nocfi annotations to runtime wrappers efi: pstore: Return proper errors on UEFI failures efi/libstub: zboot.lds: Discard .discard sections
2024-06-05efi: Add missing __nocfi annotations to runtime wrappersArd Biesheuvel
The EFI runtime wrappers are a sandbox for calling into EFI runtime services, which are invoked using indirect calls. When running with kCFI enabled, the compiler will require the target of any indirect call to be type annotated. Given that the EFI runtime services prototypes and calling convention are governed by the EFI spec, not the Linux kernel, adding such type annotations for firmware routines is infeasible, and so the compiler must be informed that prototype validation should be omitted. Add the __nocfi annotation at the appropriate places in the EFI runtime wrapper code to achieve this. Note that this currently only affects 32-bit ARM, given that other architectures that support both kCFI and EFI use an asm wrapper to call EFI runtime services, and this hides the indirect call from the compiler. Fixes: 1a4fec49efe5 ("ARM: 9392/2: Support CLANG CFI") Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-06-04Merge branch 'efi/next' into efi/urgentArd Biesheuvel
2024-06-03LoongArch: Fix entry point in kernel image headerJiaxun Yang
Currently kernel entry in head.S is in DMW address range, firmware is instructed to jump to this address after loading the kernel image. However kernel should not make any assumption on firmware's DMW setting, thus the entry point should be a physical address falls into direct translation region. Fix by converting entry address to physical and amend entry calculation logic in libstub accordingly. BTW, use ABSOLUTE() to calculate variables to make Clang/LLVM happy. Cc: stable@vger.kernel.org Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-05-23efi: pstore: Return proper errors on UEFI failuresGuilherme G. Piccoli
Right now efi-pstore either returns 0 (success) or -EIO; but we do have a function to convert UEFI errors in different standard error codes, helping to narrow down potential issues more accurately. So, let's use this helper here. Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-05-23efi/libstub: zboot.lds: Discard .discard sectionsNathan Chancellor
When building ARCH=loongarch defconfig + CONFIG_UNWINDER_ORC=y using LLVM, there is a warning from ld.lld when linking the EFI zboot image due to the use of unreachable() in number() in vsprintf.c: ld.lld: warning: drivers/firmware/efi/libstub/lib.a(vsprintf.stub.o):(.discard.unreachable+0x0): has non-ABS relocation R_LARCH_32_PCREL against symbol '' If the compiler cannot eliminate the default case for any reason, the .discard.unreachable section will remain in the final binary but the entire point of any section prefixed with .discard is that it is only used at compile time, so it can be discarded via /DISCARD/ in a linker script. The asm-generic vmlinux.lds.h includes .discard and .discard.* in the COMMON_DISCARDS macro but that is not used for zboot.lds, as it is not a kernel image linker script. Add .discard and .discard.* to /DISCARD/ in zboot.lds, so that any sections meant to be discarded at link time are not included in the final zboot image. This issue is not specific to LoongArch, it is just the first architecture to select CONFIG_OBJTOOL, which defines annotate_unreachable() as an asm statement to add the .discard.unreachable section, and use the EFI stub. Closes: https://github.com/ClangBuiltLinux/linux/issues/2023 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-05-22Merge tag 'driver-core-6.10-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the small set of driver core and kernfs changes for 6.10-rc1. Nothing major here at all, just a small set of changes for some driver core apis, and minor fixups. Included in here are: - sysfs_bin_attr_simple_read() helper added and used - device_show_string() helper added and used All usages of these were acked by the various maintainers. Also in here are: - kernfs minor cleanup - removed unused functions - typo fix in documentation - pay attention to sysfs_create_link() failures in module.c finally All of these have been in linux-next for a very long time with no reported problems" * tag 'driver-core-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: device property: Fix a typo in the description of device_get_child_node_count() kernfs: mount: Remove unnecessary ‘NULL’ values from knparent scsi: Use device_show_string() helper for sysfs attributes platform/x86: Use device_show_string() helper for sysfs attributes perf: Use device_show_string() helper for sysfs attributes IB/qib: Use device_show_string() helper for sysfs attributes hwmon: Use device_show_string() helper for sysfs attributes driver core: Add device_show_string() helper for sysfs attributes treewide: Use sysfs_bin_attr_simple_read() helper sysfs: Add sysfs_bin_attr_simple_read() helper module: don't ignore sysfs_create_link() failures driver core: Remove unused platform_notify, platform_notify_remove
2024-05-21Merge tag 'efi-fixes-for-v6.10-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fix from Ard Biesheuvel: - Followup fix for the EFI boot sequence refactor, which may result in physical KASLR putting the kernel in a region which is being used for a special purpose via a command line argument. * tag 'efi-fixes-for-v6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: x86/efistub: Omit physical KASLR when memory reservations exist
2024-05-18Merge tag 'kbuild-v6.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Avoid 'constexpr', which is a keyword in C23 - Allow 'dtbs_check' and 'dt_compatible_check' run independently of 'dt_binding_check' - Fix weak references to avoid GOT entries in position-independent code generation - Convert the last use of 'optional' property in arch/sh/Kconfig - Remove support for the 'optional' property in Kconfig - Remove support for Clang's ThinLTO caching, which does not work with the .incbin directive - Change the semantics of $(src) so it always points to the source directory, which fixes Makefile inconsistencies between upstream and downstream - Fix 'make tar-pkg' for RISC-V to produce a consistent package - Provide reasonable default coverage for objtool, sanitizers, and profilers - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc. - Remove the last use of tristate choice in drivers/rapidio/Kconfig - Various cleanups and fixes in Kconfig * tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits) kconfig: use sym_get_choice_menu() in sym_check_prop() rapidio: remove choice for enumeration kconfig: lxdialog: remove initialization with A_NORMAL kconfig: m/nconf: merge two item_add_str() calls kconfig: m/nconf: remove dead code to display value of bool choice kconfig: m/nconf: remove dead code to display children of choice members kconfig: gconf: show checkbox for choice correctly kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal Makefile: remove redundant tool coverage variables kbuild: provide reasonable defaults for tool coverage modules: Drop the .export_symbol section from the final modules kconfig: use menu_list_for_each_sym() in sym_check_choice_deps() kconfig: use sym_get_choice_menu() in conf_write_defconfig() kconfig: add sym_get_choice_menu() helper kconfig: turn defaults and additional prompt for choice members into error kconfig: turn missing prompt for choice members into error kconfig: turn conf_choice() into void function kconfig: use linked list in sym_set_changed() kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED kconfig: gconf: remove debug code ...
2024-05-17x86/efistub: Omit physical KASLR when memory reservations existArd Biesheuvel
The legacy decompressor has elaborate logic to ensure that the randomized physical placement of the decompressed kernel image does not conflict with any memory reservations, including ones specified on the command line using mem=, memmap=, efi_fake_mem= or hugepages=, which are taken into account by the kernel proper at a later stage. When booting in EFI mode, it is the firmware's job to ensure that the chosen range does not conflict with any memory reservations that it knows about, and this is trivially achieved by using the firmware's memory allocation APIs. That leaves reservations specified on the command line, though, which the firmware knows nothing about, as these regions have no other special significance to the platform. Since commit a1b87d54f4e4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot") these reservations are not taken into account when randomizing the physical placement, which may result in conflicts where the memory cannot be reserved by the kernel proper because its own executable image resides there. To avoid having to duplicate or reuse the existing complicated logic, disable physical KASLR entirely when such overrides are specified. These are mostly diagnostic tools or niche features, and physical KASLR (as opposed to virtual KASLR, which is much more important as it affects the memory addresses observed by code executing in the kernel) is something we can live without. Closes: https://lkml.kernel.org/r/FA5F6719-8824-4B04-803E-82990E65E627%40akamai.com Reported-by: Ben Chaney <bchaney@akamai.com> Fixes: a1b87d54f4e4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot") Cc: <stable@vger.kernel.org> # v6.1+ Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-05-14Merge tag 'efi-next-for-v6.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI updates from Ard Biesheuvel: "Only a handful of changes this cycle, consisting of cleanup work and a low-prio bugfix: - Additional cleanup by Tim for the efivarfs variable name length confusion - Avoid freeing a bogus pointer when virtual remapping is omitted in the EFI boot stub" * tag 'efi-next-for-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi: libstub: only free priv.runtime_map when allocated efi: Clear up misconceptions about a maximum variable name size efivarfs: Remove unused internal struct members Documentation: Mark the 'efivars' sysfs interface as removed efi: pstore: Request at most 512 bytes for variable names
2024-05-14Makefile: remove redundant tool coverage variablesMasahiro Yamada
Now Kbuild provides reasonable defaults for objtool, sanitizers, and profilers. Remove redundant variables. Note: This commit changes the coverage for some objects: - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV - include arch/sparc/vdso/vdso-image-*.o into UBSAN - include arch/sparc/vdso/vma.o into UBSAN - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vma.o into GCOV, KCOV - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV I believe these are positive effects because all of them are kernel space objects. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Roberto Sassu <roberto.sassu@huawei.com>
2024-04-29efi: libstub: only free priv.runtime_map when allocatedHagar Hemdan
priv.runtime_map is only allocated when efi_novamap is not set. Otherwise, it is an uninitialized value. In the error path, it is freed unconditionally. Avoid passing an uninitialized value to free_pool. Free priv.runtime_map only when it was allocated. This bug was discovered and resolved using Coverity Static Analysis Security Testing (SAST) by Synopsys, Inc. Fixes: f80d26043af9 ("efi: libstub: avoid efi_get_memory_map() for allocating the virt map") Cc: <stable@vger.kernel.org> Signed-off-by: Hagar Hemdan <hagarhem@amazon.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-04-24efi/unaccepted: touch soft lockup during memory acceptChen Yu
Commit 50e782a86c98 ("efi/unaccepted: Fix soft lockups caused by parallel memory acceptance") has released the spinlock so other CPUs can do memory acceptance in parallel and not triggers softlockup on other CPUs. However the softlock up was intermittent shown up if the memory of the TD guest is large, and the timeout of softlockup is set to 1 second: RIP: 0010:_raw_spin_unlock_irqrestore Call Trace: ? __hrtimer_run_queues <IRQ> ? hrtimer_interrupt ? watchdog_timer_fn ? __sysvec_apic_timer_interrupt ? __pfx_watchdog_timer_fn ? sysvec_apic_timer_interrupt </IRQ> ? __hrtimer_run_queues <TASK> ? hrtimer_interrupt ? asm_sysvec_apic_timer_interrupt ? _raw_spin_unlock_irqrestore ? __sysvec_apic_timer_interrupt ? sysvec_apic_timer_interrupt accept_memory try_to_accept_memory do_huge_pmd_anonymous_page get_page_from_freelist __handle_mm_fault __alloc_pages __folio_alloc ? __tdx_hypercall handle_mm_fault vma_alloc_folio do_user_addr_fault do_huge_pmd_anonymous_page exc_page_fault ? __do_huge_pmd_anonymous_page asm_exc_page_fault __handle_mm_fault When the local irq is enabled at the end of accept_memory(), the softlockup detects that the watchdog on single CPU has not been fed for a while. That is to say, even other CPUs will not be blocked by spinlock, the current CPU might be stunk with local irq disabled for a while, which hurts not only nmi watchdog but also softlockup. Chao Gao pointed out that the memory accept could be time costly and there was similar report before. Thus to avoid any softlocup detection during this stage, give the softlockup a flag to skip the timeout check at the end of accept_memory(), by invoking touch_softlockup_watchdog(). Reported-by: Hossain, Md Iqbal <md.iqbal.hossain@intel.com> Signed-off-by: Chen Yu <yu.c.chen@intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Fixes: 50e782a86c98 ("efi/unaccepted: Fix soft lockups caused by parallel memory acceptance") Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-04-23Merge 6.9-rc5 into driver-core-nextGreg Kroah-Hartman
We want the kernfs fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-13efi: Clear up misconceptions about a maximum variable name sizeTim Schumacher
The UEFI specification does not make any mention of a maximum variable name size, so the headers and implementation shouldn't claim that one exists either. Comments referring to this limit have been removed or rewritten, as this is an implementation detail local to the Linux kernel. Where appropriate, the magic value of 1024 has been replaced with EFI_VAR_NAME_LEN, as this is used for the efi_variable struct definition. This in itself does not change any behavior, but should serve as points of interest when making future changes in the same area. A related build-time check has been added to ensure that the special 512 byte sized buffer will not overflow with a potentially decreased EFI_VAR_NAME_LEN. Signed-off-by: Tim Schumacher <timschumi@gmx.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-04-11treewide: Use sysfs_bin_attr_simple_read() helperLukas Wunner
Deduplicate ->read() callbacks of bin_attributes which are backed by a simple buffer in memory: Use the newly introduced sysfs_bin_attr_simple_read() helper instead, either by referencing it directly or by declaring such bin_attributes with BIN_ATTR_SIMPLE_RO() or BIN_ATTR_SIMPLE_ADMIN_RO(). Aside from a reduction of LoC, this shaves off a few bytes from vmlinux (304 bytes on an x86_64 allyesconfig). No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Acked-by: Zhi Wang <zhiwang@kernel.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/92ee0a0e83a5a3f3474845db6c8575297698933a.1712410202.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-29efi: pstore: Request at most 512 bytes for variable namesTim Schumacher
Work around a quirk in a few old (2011-ish) UEFI implementations, where a call to `GetNextVariableName` with a buffer size larger than 512 bytes will always return EFI_INVALID_PARAMETER. This was already done to efivarfs in commit f45812cc23fb ("efivarfs: Request at most 512 bytes for variable names"), but the second copy of the variable iteration implementation was overlooked. Signed-off-by: Tim Schumacher <timschumi@gmx.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-28x86/efistub: Reinstate soft limit for initrd loadingArd Biesheuvel
Commit 8117961d98fb2 ("x86/efi: Disregard setup header of loaded image") dropped the memcopy of the image's setup header into the boot_params struct provided to the core kernel, on the basis that EFI boot does not need it and should rely only on a single protocol to interface with the boot chain. It is also a prerequisite for being able to increase the section alignment to 4k, which is needed to enable memory protections when running in the boot services. So only the setup_header fields that matter to the core kernel are populated explicitly, and everything else is ignored. One thing was overlooked, though: the initrd_addr_max field in the setup_header is not used by the core kernel, but it is used by the EFI stub itself when it loads the initrd, where its default value of INT_MAX is used as the soft limit for memory allocation. This means that, in the old situation, the initrd was virtually always loaded in the lower 2G of memory, but now, due to initrd_addr_max being 0x0, the initrd may end up anywhere in memory. This should not be an issue principle, as most systems can deal with this fine. However, it does appear to tickle some problems in older UEFI implementations, where the memory ends up being corrupted, resulting in errors when unpacking the initramfs. So set the initrd_addr_max field to INT_MAX like it was before. Fixes: 8117961d98fb2 ("x86/efi: Disregard setup header of loaded image") Reported-by: Radek Podgorny <radek@podgorny.cz> Closes: https://lore.kernel.org/all/a99a831a-8ad5-4cb0-bff9-be637311f771@podgorny.cz Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-28efi/libstub: Cast away type warning in use of max()Ard Biesheuvel
Avoid a type mismatch warning in max() by switching to max_t() and providing the type explicitly. Fixes: 3cb4a4827596abc82e ("efi/libstub: fix efi_random_alloc() ...") Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-24Merge tag 'efi-fixes-for-v6.9-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fixes from Ard Biesheuvel: - Fix logic that is supposed to prevent placement of the kernel image below LOAD_PHYSICAL_ADDR - Use the firmware stack in the EFI stub when running in mixed mode - Clear BSS only once when using mixed mode - Check efi.get_variable() function pointer for NULL before trying to call it * tag 'efi-fixes-for-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: efi: fix panic in kdump kernel x86/efistub: Don't clear BSS twice in mixed mode x86/efistub: Call mixed mode boot services on the firmware's stack efi/libstub: fix efi_random_alloc() to allocate memory at alloc_min or higher address
2024-03-24efi: fix panic in kdump kernelOleksandr Tymoshenko
Check if get_next_variable() is actually valid pointer before calling it. In kdump kernel this method is set to NULL that causes panic during the kexec-ed kernel boot. Tested with QEMU and OVMF firmware. Fixes: bad267f9e18f ("efi: verify that variable services are supported") Signed-off-by: Oleksandr Tymoshenko <ovt@google.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-24x86/efistub: Don't clear BSS twice in mixed modeArd Biesheuvel
Clearing BSS should only be done once, at the very beginning. efi_pe_entry() is the entrypoint from the firmware, which may not clear BSS and so it is done explicitly. However, efi_pe_entry() is also used as an entrypoint by the mixed mode startup code, in which case BSS will already have been cleared, and doing it again at this point will corrupt global variables holding the firmware's GDT/IDT and segment selectors. So make the memset() conditional on whether the EFI stub is running in native mode. Fixes: b3810c5a2cc4a666 ("x86/efistub: Clear decompressor BSS in native EFI entrypoint") Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-22Merge tag 'fbdev-for-6.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev Pull fbdev updates from Helge Deller: - Allow console fonts up to 64x128 pixels (Samuel Thibault) - Prevent division-by-zero in fb monitor code (Roman Smirnov) - Drop Renesas ARM platforms from Mobile LCDC framebuffer driver (Geert Uytterhoeven) - Various code cleanups in viafb, uveafb and mb862xxfb drivers by Aleksandr Burakov, Li Zhijian and Michael Ellerman * tag 'fbdev-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev: fbdev: panel-tpo-td043mtea1: Convert sprintf() to sysfs_emit() fbmon: prevent division by zero in fb_videomode_from_videomode() fbcon: Increase maximum font width x height to 64 x 128 fbdev: viafb: fix typo in hw_bitblt_1 and hw_bitblt_2 fbdev: mb862xxfb: Fix defined but not used error fbdev: uvesafb: Convert sprintf/snprintf to sysfs_emit fbdev: Restrict FB_SH_MOBILE_LCDC to SuperH
2024-03-22efi/libstub: fix efi_random_alloc() to allocate memory at alloc_min or ↵KONDO KAZUMA(近藤 和真)
higher address Following warning is sometimes observed while booting my servers: [ 3.594838] DMA: preallocated 4096 KiB GFP_KERNEL pool for atomic allocations [ 3.602918] swapper/0: page allocation failure: order:10, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0-1 ... [ 3.851862] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA pool for atomic allocation If 'nokaslr' boot option is set, the warning always happens. On x86, ZONE_DMA is small zone at the first 16MB of physical address space. When this problem happens, most of that space seems to be used by decompressed kernel. Thereby, there is not enough space at DMA_ZONE to meet the request of DMA pool allocation. The commit 2f77465b05b1 ("x86/efistub: Avoid placing the kernel below LOAD_PHYSICAL_ADDR") tried to fix this problem by introducing lower bound of allocation. But the fix is not complete. efi_random_alloc() allocates pages by following steps. 1. Count total available slots ('total_slots') 2. Select a slot ('target_slot') to allocate randomly 3. Calculate a starting address ('target') to be included target_slot 4. Allocate pages, which starting address is 'target' In step 1, 'alloc_min' is used to offset the starting address of memory chunk. But in step 3 'alloc_min' is not considered at all. As the result, 'target' can be miscalculated and become lower than 'alloc_min'. When KASLR is disabled, 'target_slot' is always 0 and the problem happens everytime if the EFI memory map of the system meets the condition. Fix this problem by calculating 'target' considering 'alloc_min'. Cc: linux-efi@vger.kernel.org Cc: Tom Englund <tomenglund26@gmail.com> Cc: linux-kernel@vger.kernel.org Fixes: 2f77465b05b1 ("x86/efistub: Avoid placing the kernel below LOAD_PHYSICAL_ADDR") Signed-off-by: Kazuma Kondo <kazuma-kondo@nec.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-21Merge tag 'driver-core-6.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core and kernfs changes for 6.9-rc1. Nothing all that crazy here, just some good updates that include: - automatic attribute group hiding from Dan Williams (he fixed up my horrible attempt at doing this.) - kobject lock contention fixes from Eric Dumazet - driver core cleanups from Andy - kernfs rcu work from Tejun - fw_devlink changes to resolve some reported issues - other minor changes, all details in the shortlog All of these have been in linux-next for a long time with no reported issues" * tag 'driver-core-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (28 commits) device: core: Log warning for devices pending deferred probe on timeout driver: core: Use dev_* instead of pr_* so device metadata is added driver: core: Log probe failure as error and with device metadata of: property: fw_devlink: Add support for "post-init-providers" property driver core: Add FWLINK_FLAG_IGNORE to completely ignore a fwnode link driver core: Adds flags param to fwnode_link_add() debugfs: fix wait/cancellation handling during remove device property: Don't use "proxy" headers device property: Move enum dev_dma_attr to fwnode.h driver core: Move fw_devlink stuff to where it belongs driver core: Drop unneeded 'extern' keyword in fwnode.h firmware_loader: Suppress warning on FW_OPT_NO_WARN flag sysfs:Addresses documentation in sysfs_merge_group and sysfs_unmerge_group. firmware_loader: introduce __free() cleanup hanler platform-msi: Remove usage of the deprecated ida_simple_xx() API sysfs: Introduce DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE() sysfs: Document new "group visible" helpers sysfs: Fix crash on empty group attributes array sysfs: Introduce a mechanism to hide static attribute_groups sysfs: Introduce a mechanism to hide static attribute_groups ...
2024-03-17Merge tag 'efi-fixes-for-v6.9-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi Pull EFI fix from Ard Biesheuvel: "This fixes an oversight on my part in the recent EFI stub rework for x86, which is needed to get Linux/x86 distro builds signed again for secure boot by Microsoft. For this reason, most of this work is being backported to v6.1, which is therefore also affected by this regression. - Explicitly wipe BSS in the native EFI entrypoint, so that globals shared with the legacy decompressor are zero-initialized correctly" * tag 'efi-fixes-for-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: x86/efistub: Clear decompressor BSS in native EFI entrypoint