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2024-04-10RISC-V: Update AT_VECTOR_SIZE_ARCH for new AT_MINSIGSTKSZVictor Isaev1-1/+1
[ Upstream commit 13dddf9319808badd2c1f5d7007b4e82838a648e ] "riscv: signal: Report signal frame size to userspace via auxv" (e92f469) has added new constant AT_MINSIGSTKSZ but failed to increment the size of auxv, keeping AT_VECTOR_SIZE_ARCH at 9. This fix correctly increments AT_VECTOR_SIZE_ARCH to 10, following the approach in the commit 94b07c1 ("arm64: signal: Report signal frame size to userspace via auxv"). Link: https://lore.kernel.org/r/73883406.20231215232720@torrio.net Link: https://lore.kernel.org/all/20240102133617.3649-1-victor@torrio.net/ Reported-by: Ivan Komarov <ivan.komarov@dfyz.info> Closes: https://lore.kernel.org/linux-riscv/CY3Z02NYV1C4.11BLB9PLVW9G1@fedora/ Fixes: e92f469b0771 ("riscv: signal: Report signal frame size to userspace via auxv") Signed-off-by: Victor Isaev <isv@google.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-10Merge tag 'riscv-for-linus-6.6-mw2-2' of ↵Linus Torvalds1-4/+9
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - The kernel now dynamically probes for misaligned access speed, as opposed to relying on a table of known implementations. - Support for non-coherent devices on systems using the Andes AX45MP core, including the RZ/Five SoCs. - Support for the V extension in ptrace(), again. - Support for KASLR. - Support for the BPF prog pack allocator in RISC-V. - A handful of bug fixes and cleanups. * tag 'riscv-for-linus-6.6-mw2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (25 commits) soc: renesas: Kconfig: For ARCH_R9A07G043 select the required configs if dependencies are met riscv: Kconfig.errata: Add dependency for RISCV_SBI in ERRATA_ANDES config riscv: Kconfig.errata: Drop dependency for MMU in ERRATA_ANDES_CMO config riscv: Kconfig: Select DMA_DIRECT_REMAP only if MMU is enabled bpf, riscv: use prog pack allocator in the BPF JIT riscv: implement a memset like function for text riscv: extend patch_text_nosync() for multiple pages bpf: make bpf_prog_pack allocator portable riscv: libstub: Implement KASLR by using generic functions libstub: Fix compilation warning for rv32 arm64: libstub: Move KASLR handling functions to kaslr.c riscv: Dump out kernel offset information on panic riscv: Introduce virtual kernel mapping KASLR RISC-V: Add ptrace support for vectors soc: renesas: Kconfig: Select the required configs for RZ/Five SoC cache: Add L2 cache management for Andes AX45MP RISC-V core dt-bindings: cache: andestech,ax45mp-cache: Add DT binding documentation for L2 cache controller riscv: mm: dma-noncoherent: nonstandard cache operations support riscv: errata: Add Andes alternative ports riscv: asm: vendorid_list: Add Andes Technology to the vendors list ...
2023-09-08Merge patch "RISC-V: Add ptrace support for vectors"Palmer Dabbelt1-4/+9
This resurrects the vector ptrace() support that was removed for 6.5 due to some bugs cropping up as part of the GDB review process. * b4-shazam-merge: RISC-V: Add ptrace support for vectors Link: https://lore.kernel.org/r/20230825050248.32681-1-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-07Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-0/+16
Pull kvm updates from Paolo Bonzini: "ARM: - Clean up vCPU targets, always returning generic v8 as the preferred target - Trap forwarding infrastructure for nested virtualization (used for traps that are taken from an L2 guest and are needed by the L1 hypervisor) - FEAT_TLBIRANGE support to only invalidate specific ranges of addresses when collapsing a table PTE to a block PTE. This avoids that the guest refills the TLBs again for addresses that aren't covered by the table PTE. - Fix vPMU issues related to handling of PMUver. - Don't unnecessary align non-stack allocations in the EL2 VA space - Drop HCR_VIRT_EXCP_MASK, which was never used... - Don't use smp_processor_id() in kvm_arch_vcpu_load(), but the cpu parameter instead - Drop redundant call to kvm_set_pfn_accessed() in user_mem_abort() - Remove prototypes without implementations RISC-V: - Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for guest - Added ONE_REG interface for SATP mode - Added ONE_REG interface to enable/disable multiple ISA extensions - Improved error codes returned by ONE_REG interfaces - Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V - Added get-reg-list selftest for KVM RISC-V s390: - PV crypto passthrough enablement (Tony, Steffen, Viktor, Janosch) Allows a PV guest to use crypto cards. Card access is governed by the firmware and once a crypto queue is "bound" to a PV VM every other entity (PV or not) looses access until it is not bound anymore. Enablement is done via flags when creating the PV VM. - Guest debug fixes (Ilya) x86: - Clean up KVM's handling of Intel architectural events - Intel bugfixes - Add support for SEV-ES DebugSwap, allowing SEV-ES guests to use debug registers and generate/handle #DBs - Clean up LBR virtualization code - Fix a bug where KVM fails to set the target pCPU during an IRTE update - Fix fatal bugs in SEV-ES intrahost migration - Fix a bug where the recent (architecturally correct) change to reinject #BP and skip INT3 broke SEV guests (can't decode INT3 to skip it) - Retry APIC map recalculation if a vCPU is added/enabled - Overhaul emergency reboot code to bring SVM up to par with VMX, tie the "emergency disabling" behavior to KVM actually being loaded, and move all of the logic within KVM - Fix user triggerable WARNs in SVM where KVM incorrectly assumes the TSC ratio MSR cannot diverge from the default when TSC scaling is disabled up related code - Add a framework to allow "caching" feature flags so that KVM can check if the guest can use a feature without needing to search guest CPUID - Rip out the ancient MMU_DEBUG crud and replace the useful bits with CONFIG_KVM_PROVE_MMU - Fix KVM's handling of !visible guest roots to avoid premature triple fault injection - Overhaul KVM's page-track APIs, and KVMGT's usage, to reduce the API surface that is needed by external users (currently only KVMGT), and fix a variety of issues in the process Generic: - Wrap kvm_{gfn,hva}_range.pte in a union to allow mmu_notifier events to pass action specific data without needing to constantly update the main handlers. - Drop unused function declarations Selftests: - Add testcases to x86's sync_regs_test for detecting KVM TOCTOU bugs - Add support for printf() in guest code and covert all guest asserts to use printf-based reporting - Clean up the PMU event filter test and add new testcases - Include x86 selftests in the KVM x86 MAINTAINERS entry" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (279 commits) KVM: x86/mmu: Include mmu.h in spte.h KVM: x86/mmu: Use dummy root, backed by zero page, for !visible guest roots KVM: x86/mmu: Disallow guest from using !visible slots for page tables KVM: x86/mmu: Harden TDP MMU iteration against root w/o shadow page KVM: x86/mmu: Harden new PGD against roots without shadow pages KVM: x86/mmu: Add helper to convert root hpa to shadow page drm/i915/gvt: Drop final dependencies on KVM internal details KVM: x86/mmu: Handle KVM bookkeeping in page-track APIs, not callers KVM: x86/mmu: Drop @slot param from exported/external page-track APIs KVM: x86/mmu: Bug the VM if write-tracking is used but not enabled KVM: x86/mmu: Assert that correct locks are held for page write-tracking KVM: x86/mmu: Rename page-track APIs to reflect the new reality KVM: x86/mmu: Drop infrastructure for multiple page-track modes KVM: x86/mmu: Use page-track notifiers iff there are external users KVM: x86/mmu: Move KVM-only page-track declarations to internal header KVM: x86: Remove the unused page-track hook track_flush_slot() drm/i915/gvt: switch from ->track_flush_slot() to ->track_remove_region() KVM: x86: Add a new page-track hook to handle memslot deletion drm/i915/gvt: Don't bother removing write-protection on to-be-deleted slot KVM: x86: Reject memslot MOVE operations if KVMGT is attached ...
2023-09-01RISC-V: Add ptrace support for vectorsAndy Chiu1-4/+9
This patch add back the ptrace support with the following fix: - Define NT_RISCV_CSR and re-number NT_RISCV_VECTOR to prevent conflicting with gdb's NT_RISCV_CSR. - Use struct __riscv_v_regset_state to handle ptrace requests Since gdb does not directly include the note description header in Linux and has already defined NT_RISCV_CSR as 0x900, we decide to sync with gdb and renumber NT_RISCV_VECTOR to solve and prevent future conflicts. Fixes: 0c59922c769a ("riscv: Add ptrace vector support") Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Link: https://lore.kernel.org/r/20230825050248.32681-1-andy.chiu@sifive.com [Palmer: Drop the unused "size" variable in riscv_vr_set().] Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-01Merge tag 'riscv-for-linus-6.6-mw1' of ↵Linus Torvalds2-1/+6
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the new "riscv,isa-extensions" and "riscv,isa-base" device tree interfaces for probing extensions - Support for userspace access to the performance counters - Support for more instructions in kprobes - Crash kernels can be allocated above 4GiB - Support for KCFI - Support for ELFs in !MMU configurations - ARCH_KMALLOC_MINALIGN has been reduced to 8 - mmap() defaults to sv48-sized addresses, with longer addresses hidden behind a hint (similar to Arm and Intel) - Also various fixes and cleanups * tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V riscv: support PREEMPT_DYNAMIC with static keys riscv: Move create_tmp_mapping() to init sections riscv: Mark KASAN tmp* page tables variables as static riscv: mm: use bitmap_zero() API riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B riscv: remove redundant mv instructions RISC-V: mm: Document mmap changes RISC-V: mm: Update pgtable comment documentation RISC-V: mm: Add tests for RISC-V mm RISC-V: mm: Restrict address space for sv39,sv48,sv57 riscv: enable DMA_BOUNCE_UNALIGNED_KMALLOC for !dma_coherent riscv: allow kmalloc() caches aligned to the smallest value riscv: support the elf-fdpic binfmt loader binfmt_elf_fdpic: support 64-bit systems riscv: Allow CONFIG_CFI_CLANG to be selected riscv/purgatory: Disable CFI riscv: Add CFI error handling riscv: Add ftrace_stub_graph riscv: Add types to indirectly called assembly functions ...
2023-08-31Merge tag 'kvm-riscv-6.6-1' of https://github.com/kvm-riscv/linux into HEADPaolo Bonzini1-0/+16
KVM/riscv changes for 6.6 - Zba, Zbs, Zicntr, Zicsr, Zifencei, and Zihpm support for Guest/VM - Added ONE_REG interface for SATP mode - Added ONE_REG interface to enable/disable multiple ISA extensions - Improved error codes returned by ONE_REG interfaces - Added KVM_GET_REG_LIST ioctl() implementation for KVM RISC-V - Added get-reg-list selftest for KVM RISC-V
2023-08-31Merge patch series "riscv: support ELF format binaries in nommu mode"Palmer Dabbelt1-0/+5
Greg Ungerer <gerg@kernel.org> says: The following changes add the ability to run ELF format binaries when running RISC-V in nommu mode. That support is actually part of the ELF-FDPIC loader, so these changes are all about making that work on RISC-V. The first issue to deal with is making the ELF-FDPIC loader capable of handling 64-bit ELF files. As coded right now it only supports 32-bit ELF files. Secondly some changes are required to enable and compile the ELF-FDPIC loader on RISC-V and to pass the ELF-FDPIC mapping addresses through to user space when execing the new program. These changes have not been used to run actual ELF-FDPIC binaries. It is used to load and run normal ELF - compiled -pie format. Though the underlying changes are expected to work with full ELF-FDPIC binaries if or when that is supported on RISC-V in gcc. To avoid needing changes to the C-library (tested with uClibc-ng currently) there is a simple runtime dynamic loader (interpreter) available to do the final relocations, https://github.com/gregungerer/uldso. The nice thing about doing it this way is that the same program binary can also be loaded with the usual ELF loader in MMU linux. The motivation here is to provide an easy to use alternative to the flat format binaries normally used for RISC-V nommu based systems. * b4-shazam-merge: riscv: support the elf-fdpic binfmt loader binfmt_elf_fdpic: support 64-bit systems Link: https://lore.kernel.org/r/20230711130754.481209-1-gerg@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-25Merge tag 'riscv-for-linus-6.5-rc8' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: "This is obviously not ideal, particularly for something this late in the cycle. Unfortunately we found some uABI issues in the vector support while reviewing the GDB port, which has triggered a revert -- probably a good sign we should have reviewed GDB before merging this, I guess I just dropped the ball because I was so worried about the context extension and libc suff I forgot. Hence the late revert. There's some risk here as we're still exposing the vector context for signal handlers, but changing that would have meant reverting all of the vector support. The issues we've found so far have been fixed already and they weren't absolute showstoppers, so we're essentially just playing it safe by holding ptrace support for another release (or until we get through a proper userspace code review). Summary: - The vector ucontext extension has been extended with vlenb - The vector registers ELF core dump note type has been changed to avoid aliasing with the CSR type used in embedded systems - Support for accessing vector registers via ptrace() has been reverted - Another build fix for the ISA spec changes around Zifencei/Zicsr that manifests on some systems built with binutils-2.37 and gcc-11.2" * tag 'riscv-for-linus-6.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Fix build errors using binutils2.37 toolchains RISC-V: vector: export VLENB csr in __sc_riscv_v_state RISC-V: Remove ptrace support for vectors
2023-08-24riscv: support the elf-fdpic binfmt loaderGreg Ungerer1-0/+5
Add support for enabling and using the binfmt_elf_fdpic program loader on RISC-V platforms. The most important change is to setup registers during program load to pass the mapping addresses to the new process. One of the interesting features of the elf-fdpic loader is that it also allows appropriately compiled ELF format binaries to be loaded on nommu systems. Appropriate being those compiled with -pie. Signed-off-by: Greg Ungerer <gerg@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230711130754.481209-3-gerg@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-22RISC-V: vector: export VLENB csr in __sc_riscv_v_stateAndy Chiu1-0/+1
VLENB is critical for callers of ptrace to reconstruct Vector register files from the register dump of NT_RISCV_VECTOR. Also, future systems may will have a writable VLENB, so add it now to potentially save future compatibility issue. Fixes: 0c59922c769a ("riscv: Add ptrace vector support") Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Link: https://lore.kernel.org/r/20230816155450.26200-3-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-18Merge tag 'asm-generic-fix-6.5' of ↵Linus Torvalds1-0/+14
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic regression fix from Arnd Bergmann: "Just one partial revert for a commit from the merge window that caused annoying behavior when building old kernels on arm64 hosts" * tag 'asm-generic-fix-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: asm-generic: partially revert "Unify uapi bitsperlong.h for arm64, riscv and loongarch"
2023-08-17asm-generic: partially revert "Unify uapi bitsperlong.h for arm64, riscv and ↵Arnd Bergmann1-0/+14
loongarch" Unifying the asm-generic headers across 32-bit and 64-bit architectures based on the compiler provided macros was a good idea and appears to work with all user space, but it caused a regression when building old kernels on systems that have the new headers installed in /usr/include, as this combination trips an inconsistency in the kernel's own tools/include headers that are a mix of userspace and kernel-internal headers. This affects kernel builds on arm64, riscv64 and loongarch64 systems that might end up using the "#define __BITS_PER_LONG 32" default from the old tools headers. Backporting the commit into stable kernels would address this, but it would still break building kernels without that backport, and waste time for developers trying to understand the problem. arm64 build machines are rather common, and on riscv64 this can also happen in practice, but loongarch64 is probably new enough to not be used much for building old kernels, so only revert the bits for arm64 and riscv. Link: https://lore.kernel.org/all/20230731160402.GB1823389@dev-arch.thelio-3990X/ Reported-by: Nathan Chancellor <nathan@kernel.org> Fixes: 8386f58f8deda ("asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch") Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-08-08RISC-V: KVM: provide UAPI for host SATP modeDaniel Henrique Barboza1-0/+1
KVM userspaces need to be aware of the host SATP to allow them to advertise it back to the guest OS. Since this information is used to build the guest FDT we can't wait for the SATP reg to be readable. We just need to read the SATP mode, thus we can use the existing 'satp_mode' global that represents the SATP reg with MODE set and both ASID and PPN cleared. E.g. for a 32 bit host running with sv32 satp_mode is 0x80000000, for a 64 bit host running sv57 satp_mode is 0xa000000000000000, and so on. Add a new userspace virtual config register 'satp_mode' to allow userspace to read the current SATP mode the host is using with GET_ONE_REG API before spinning the vcpu. 'satp_mode' can't be changed via KVM, so SET_ONE_REG is allowed as long as userspace writes the existing 'satp_mode'. Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-08-08RISC-V: KVM: Allow Zicntr, Zicsr, Zifencei, and Zihpm for Guest/VMAnup Patel1-0/+4
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zicntr, Zicsr, Zifencei, and Zihpm extensions for Guest/VM. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-08-08RISC-V: KVM: Allow Zba and Zbs extensions for Guest/VMAnup Patel1-0/+2
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zba and Zbs extensions for Guest/VM. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-08-08RISC-V: KVM: Extend ONE_REG to enable/disable multiple ISA extensionsAnup Patel1-0/+9
Currently, the ISA extension ONE_REG interface only allows enabling or disabling one extension at a time. To improve this, we extend the ISA extension ONE_REG interface (similar to SBI extension ONE_REG interface) so that KVM user space can enable/disable multiple extensions in one ioctl. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-07-11riscv: sigcontext: Correct the comment of sigreturnGuo Ren1-1/+1
The real-time signals enlarged the sigset_t type, and most architectures have changed to using rt_sigreturn as the only way. The riscv is one of them, and there is no sys_sigreturn in it. Only some old architecture preserved sys_sigreturn as part of the historical burden. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Link: https://lore.kernel.org/r/20230628091213.2908149-1-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-07-07Merge tag 'riscv-for-linus-6.5-mw2' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - A bunch of fixes/cleanups from the first part of the merge window, mostly related to ACPI and vector as those were large - Some documentation improvements, mostly related to the new code - The "riscv,isa" DT key is deprecated - Support for link-time dead code elimination - Support for minor fault registration in userfaultd - A handful of cleanups around CMO alternatives * tag 'riscv-for-linus-6.5-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (23 commits) riscv: mm: mark noncoherent_supported as __ro_after_init riscv: mm: mark CBO relate initialization funcs as __init riscv: errata: thead: only set cbom size & noncoherent during boot riscv: Select HAVE_ARCH_USERFAULTFD_MINOR RISC-V: Document the ISA string parsing rules for ACPI risc-v: Fix order of IPI enablement vs RCU startup mm: riscv: fix an unsafe pte read in huge_pte_alloc() dt-bindings: riscv: deprecate riscv,isa RISC-V: drop error print from riscv_hartid_to_cpuid() riscv: Discard vector state on syscalls riscv: move memblock_allow_resize() after linear mapping is ready riscv: Enable ARCH_SUSPEND_POSSIBLE for s2idle riscv: vdso: include vdso/vsyscall.h for vdso_data selftests: Test RISC-V Vector's first-use handler riscv: vector: clear V-reg in the first-use trap riscv: vector: only enable interrupts in the first-use trap RISC-V: Fix up some vector state related build failures RISC-V: Document that V registers are clobbered on syscalls riscv: disable HAVE_LD_DEAD_CODE_DATA_ELIMINATION for LLD riscv: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION ...
2023-07-06Merge tag 'asm-generic-6.5' of ↵Linus Torvalds1-14/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "These are cleanups for architecture specific header files: - the comments in include/linux/syscalls.h have gone out of sync and are really pointless, so these get removed - The asm/bitsperlong.h header no longer needs to be architecture specific on modern compilers, so use a generic version for newer architectures that use new enough userspace compilers - A cleanup for virt_to_pfn/virt_to_bus to have proper type checking, forcing the use of pointers" * tag 'asm-generic-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: syscalls: Remove file path comments from headers tools arch: Remove uapi bitsperlong.h of hexagon and microblaze asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch m68k/mm: Make pfn accessors static inlines arm64: memory: Make virt_to_pfn() a static inline ARM: mm: Make virt_to_pfn() a static inline asm-generic/page.h: Make pfn accessors static inlines xen/netback: Pass (void *) to virt_to_page() netfs: Pass a pointer to virt_to_page() cifs: Pass a pointer to virt_to_page() in cifsglob cifs: Pass a pointer to virt_to_page() riscv: mm: init: Pass a pointer to virt_to_page() ARC: init: Pass a pointer to virt_to_pfn() in init m68k: Pass a pointer to virt_to_pfn() virt_to_page() fs/proc/kcore.c: Pass a pointer to virt_addr_valid()
2023-07-04Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-0/+73
Pull kvm updates from Paolo Bonzini: "ARM64: - Eager page splitting optimization for dirty logging, optionally allowing for a VM to avoid the cost of hugepage splitting in the stage-2 fault path. - Arm FF-A proxy for pKVM, allowing a pKVM host to safely interact with services that live in the Secure world. pKVM intervenes on FF-A calls to guarantee the host doesn't misuse memory donated to the hyp or a pKVM guest. - Support for running the split hypervisor with VHE enabled, known as 'hVHE' mode. This is extremely useful for testing the split hypervisor on VHE-only systems, and paves the way for new use cases that depend on having two TTBRs available at EL2. - Generalized framework for configurable ID registers from userspace. KVM/arm64 currently prevents arbitrary CPU feature set configuration from userspace, but the intent is to relax this limitation and allow userspace to select a feature set consistent with the CPU. - Enable the use of Branch Target Identification (FEAT_BTI) in the hypervisor. - Use a separate set of pointer authentication keys for the hypervisor when running in protected mode, as the host is untrusted at runtime. - Ensure timer IRQs are consistently released in the init failure paths. - Avoid trapping CTR_EL0 on systems with Enhanced Virtualization Traps (FEAT_EVT), as it is a register commonly read from userspace. - Erratum workaround for the upcoming AmpereOne part, which has broken hardware A/D state management. RISC-V: - Redirect AMO load/store misaligned traps to KVM guest - Trap-n-emulate AIA in-kernel irqchip for KVM guest - Svnapot support for KVM Guest s390: - New uvdevice secret API - CMM selftest and fixes - fix racy access to target CPU for diag 9c x86: - Fix missing/incorrect #GP checks on ENCLS - Use standard mmu_notifier hooks for handling APIC access page - Drop now unnecessary TR/TSS load after VM-Exit on AMD - Print more descriptive information about the status of SEV and SEV-ES during module load - Add a test for splitting and reconstituting hugepages during and after dirty logging - Add support for CPU pinning in demand paging test - Add support for AMD PerfMonV2, with a variety of cleanups and minor fixes included along the way - Add a "nx_huge_pages=never" option to effectively avoid creating NX hugepage recovery threads (because nx_huge_pages=off can be toggled at runtime) - Move handling of PAT out of MTRR code and dedup SVM+VMX code - Fix output of PIC poll command emulation when there's an interrupt - Add a maintainer's handbook to document KVM x86 processes, preferred coding style, testing expectations, etc. - Misc cleanups, fixes and comments Generic: - Miscellaneous bugfixes and cleanups Selftests: - Generate dependency files so that partial rebuilds work as expected" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (153 commits) Documentation/process: Add a maintainer handbook for KVM x86 Documentation/process: Add a label for the tip tree handbook's coding style KVM: arm64: Fix misuse of KVM_ARM_VCPU_POWER_OFF bit index RISC-V: KVM: Remove unneeded semicolon RISC-V: KVM: Allow Svnapot extension for Guest/VM riscv: kvm: define vcpu_sbi_ext_pmu in header RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchip RISC-V: KVM: Add in-kernel virtualization of AIA IMSIC RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip RISC-V: KVM: Add in-kernel emulation of AIA APLIC RISC-V: KVM: Implement device interface for AIA irqchip RISC-V: KVM: Skeletal in-kernel AIA irqchip support RISC-V: KVM: Set kvm_riscv_aia_nr_hgei to zero RISC-V: KVM: Add APLIC related defines RISC-V: KVM: Add IMSIC related defines RISC-V: KVM: Implement guest external interrupt line management KVM: x86: Remove PRIx* definitions as they are solely for user space s390/uv: Update query for secret-UVCs s390/uv: replace scnprintf with sysfs_emit s390/uvdevice: Add 'Lock Secret Store' UVC ...
2023-07-01RISC-V: Fix up some vector state related build failuresPalmer Dabbelt1-0/+4
I get a few build failures along the lines of ./arch/riscv/include/uapi/asm/sigcontext.h:19:36: error: field ‘v_state’ has incomplete type 19 | struct __riscv_v_ext_state v_state; | ^~~~~~~ ./arch/riscv/include/uapi/asm/sigcontext.h:32:49: error: field ‘sc_extdesc’ has incomplete type 32 | struct __riscv_extra_ext_header sc_extdesc; The V structures in question are defined for !assembly, so let's just do so for the others. Fixes: 8ee0b41898fa ("riscv: signal: Add sigcontext save/restore for vector") Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230619172101.18692-1-palmer@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-22asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarchTiezhu Yang1-14/+0
Now we specify the minimal version of GCC as 5.1 and Clang/LLVM as 11.0.0 in Documentation/process/changes.rst, __CHAR_BIT__ and __SIZEOF_LONG__ are usable, it is probably fine to unify the definition of __BITS_PER_LONG as (__CHAR_BIT__ * __SIZEOF_LONG__) in asm-generic uapi bitsperlong.h. In order to keep safe and avoid regression, only unify uapi bitsperlong.h for some archs such as arm64, riscv and loongarch which are using newer toolchains that have the definitions of __CHAR_BIT__ and __SIZEOF_LONG__. Suggested-by: Xi Ruoyao <xry111@xry111.site> Link: https://lore.kernel.org/all/d3e255e4746de44c9903c4433616d44ffcf18d1b.camel@xry111.site/ Suggested-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/linux-arch/a3a4f48a-07d4-4ed9-bc53-5d383428bdd2@app.fastmail.com/ Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-06-20RISC-V: KVM: Allow Svnapot extension for Guest/VMAnup Patel1-0/+1
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Svnapot extension for Guest/VM. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-06-20Merge patch series "RISC-V: Export Zba, Zbb to usermode via hwprobe"Palmer Dabbelt1-0/+3
Evan Green <evan@rivosinc.com> says: This change detects the presence of Zba, Zbb, and Zbs extensions and exports them per-hart to userspace via the hwprobe mechanism. Glibc can then use these in setting up hwcaps-based library search paths. There's a little bit of extra housekeeping here: the first change adds Zba and Zbs to the set of extensions the kernel recognizes, and the second change starts tracking ISA features per-hart (in addition to the ANDed mask of features across all harts which the kernel uses to make decisions). Now that we track the ISA information per-hart, we could even fix up /proc/cpuinfo to accurately report extension per-hart, though I've left that out of this series for now. * b4-shazam-merge: RISC-V: hwprobe: Expose Zba, Zbb, and Zbs RISC-V: Track ISA extensions per hart RISC-V: Add Zba, Zbs extension probing Link: https://lore.kernel.org/r/20230509182504.2997252-1-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchipAnup Patel1-0/+17
We expose IMSIC registers as KVM device attributes of the in-kernel AIA irqchip device. This will allow KVM user-space to save/restore IMISC state of each VCPU using KVM device ioctls(). Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-06-19RISC-V: hwprobe: Expose Zba, Zbb, and ZbsEvan Green1-0/+3
Add two new bits to the IMA_EXT_0 key for ZBA, ZBB, and ZBS extensions. These are accurately reported per CPU. Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230509182504.2997252-4-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-18RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchipAnup Patel1-0/+6
We expose APLIC registers as KVM device attributes of the in-kernel AIA irqchip device. This will allow KVM user-space to save/restore APLIC state using KVM device ioctls(). Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-06-18RISC-V: KVM: Implement device interface for AIA irqchipAnup Patel1-0/+45
We implement KVM device interface for in-kernel AIA irqchip so that user-space can use KVM device ioctls to create, configure, and destroy in-kernel AIA irqchip. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-06-18RISC-V: KVM: Skeletal in-kernel AIA irqchip supportAnup Patel1-0/+4
To incrementally implement in-kernel AIA irqchip support, we first add minimal skeletal support which only compiles but does not provide any functionality. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-06-08riscv: KVM: Add vector lazy save/restore supportVincent Chen1-0/+7
This patch adds vector context save/restore for guest VCPUs. To reduce the impact on KVM performance, the implementation imitates the FP context switch mechanism to lazily store and restore the vector context only when the kernel enters/exits the in-kernel run loop and not during the KVM world switch. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20230605110724.21391-20-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: kvm: Add V extension to KVM ISAVincent Chen1-0/+1
Add V extension to KVM isa extension list to enable supporting of V extension on VCPUs. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-19-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: signal: Report signal frame size to userspace via auxvVincent Chen1-0/+1
The vector register belongs to the signal context. They need to be stored and restored as entering and leaving the signal handler. According to the V-extension specification, the maximum length of the vector registers can be 2^16. Hence, if userspace refers to the MINSIGSTKSZ to create a sigframe, it may not be enough. To resolve this problem, this patch refers to the commit 94b07c1f8c39c ("arm64: signal: Report signal frame size to userspace via auxv") to enable userspace to know the minimum required sigframe size through the auxiliary vector and use it to allocate enough memory for signal context. Note that auxv always reports size of the sigframe as if V exists for all starting processes, whenever the kernel has CONFIG_RISCV_ISA_V. The reason is that users usually reference this value to allocate an alternative signal stack, and the user may use V anytime. So the user must reserve a space for V-context in sigframe in case that the signal handler invokes after the kernel allocating V. Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-16-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: signal: Add sigcontext save/restore for vectorGreentime Hu2-1/+30
This patch facilitates the existing fp-reserved words for placement of the first extension's context header on the user's sigframe. A context header consists of a distinct magic word and the size, including the header itself, of an extension on the stack. Then, the frame is followed by the context of that extension, and then a header + context body for another extension if exists. If there is no more extension to come, then the frame must be ended with a null context header. A special case is rv64gc, where the kernel support no extensions requiring to expose additional regfile to the user. In such case the kernel would place the null context header right after the first reserved word of __riscv_q_ext_state when saving sigframe. And the kernel would check if all reserved words are zeros when a signal handler returns. __riscv_q_ext_state---->| |<-__riscv_extra_ext_header ~ ~ .reserved[0]--->|0 |<- .reserved <-------|magic |<- .hdr | |size |_______ end of sc_fpregs | |ext-bdy| | ~ ~ +)size ------->|magic |<- another context header |size | |ext-bdy| ~ ~ |magic:0|<- null context header |size:0 | The vector registers will be saved in datap pointer. The datap pointer will be allocated dynamically when the task needs in kernel space. On the other hand, datap pointer on the sigframe will be set right after the __riscv_v_ext_state data structure. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Acked-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-15-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Add ptrace vector supportGreentime Hu1-0/+7
This patch adds ptrace support for riscv vector. The vector registers will be saved in datap pointer of __riscv_v_ext_state. This pointer will be set right after the __riscv_v_ext_state data structure then it will be put in ubuf for ptrace system call to get or set. It will check if the datap got from ubuf is set to the correct address or not when the ptrace system call is trying to set the vector registers. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-13-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Introduce struct/helpers to save/restore per-task Vector stateGreentime Hu1-0/+17
Add vector state context struct to be added later in thread_struct. And prepare low-level helper functions to save/restore vector contexts. This include Vector Regfile and CSRs holding dynamic configuration state (vstart, vl, vtype, vcsr). The Vec Register width could be implementation defined, but same for all processes, so that is saved separately. This is not yet wired into final thread_struct - will be done when __switch_to actually starts doing this in later patches. Given the variable (and potentially large) size of regfile, they are saved in dynamically allocated memory, pointed to by datap pointer in __riscv_v_ext_state. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-10-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: hwprobe: Add support for probing V in RISCV_HWPROBE_KEY_IMA_EXT_0Andy Chiu1-0/+1
Probing kernel support for Vector extension is available now. This only add detection for V only. Extenions like Zvfh, Zk are not in this scope. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Evan Green <evan@rivosinc.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-4-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Extending cpufeature.c to detect V-extensionGuo Ren1-0/+1
Add V-extension into riscv_isa_ext_keys array and detect it with isa string parsing. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-3-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-05-05Merge tag 'kvm-riscv-6.4-1' of https://github.com/kvm-riscv/linux into HEADPaolo Bonzini1-1/+50
KVM/riscv changes for 6.4 - ONE_REG interface to enable/disable SBI extensions - Zbb extension for Guest/VM - AIA CSR virtualization
2023-04-21RISC-V: KVM: Virtualize per-HART AIA CSRsAnup Patel1-0/+7
The AIA specification introduce per-HART AIA CSRs which primarily support: * 64 local interrupts on both RV64 and RV32 * priority for each of the 64 local interrupts * interrupt filtering for local interrupts This patch virtualize above mentioned AIA CSRs and also extend ONE_REG interface to allow user-space save/restore Guest/VM view of these CSRs. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Add ONE_REG interface for AIA CSRsAnup Patel1-0/+8
We implement ONE_REG interface for AIA CSRs as a separate subtype under the CSR ONE_REG interface. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Implement subtype for CSR ONE_REG interfaceAnup Patel1-1/+2
To make the CSR ONE_REG interface extensible, we implement subtype for the CSR ONE_REG IDs. The existing CSR ONE_REG IDs are treated as subtype = 0 (aka General CSRs). Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Allow Zbb extension for Guest/VMAnup Patel1-0/+1
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zbb extension for Guest/VM. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Add ONE_REG interface to enable/disable SBI extensionsAnup Patel1-0/+32
We add ONE_REG interface to enable/disable SBI extensions (just like the ONE_REG interface for ISA extensions). This allows KVM user-space to decide the set of SBI extension enabled for a Guest and by default all SBI extensions are enabled. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-19Merge patch series "RISC-V Hardware Probing User Interface"Palmer Dabbelt2-0/+46
Evan Green <evan@rivosinc.com> says: There's been a bunch of off-list discussions about this, including at Plumbers. The original plan was to do something involving providing an ISA string to userspace, but ISA strings just aren't sufficient for a stable ABI any more: in order to parse an ISA string users need the version of the specifications that the string is written to, the version of each extension (sometimes at a finer granularity than the RISC-V releases/versions encode), and the expected use case for the ISA string (ie, is it a U-mode or M-mode string). That's a lot of complexity to try and keep ABI compatible and it's probably going to continue to grow, as even if there's no more complexity in the specifications we'll have to deal with the various ISA string parsing oddities that end up all over userspace. Instead this patch set takes a very different approach and provides a set of key/value pairs that encode various bits about the system. The big advantage here is that we can clearly define what these mean so we can ensure ABI stability, but it also allows us to encode information that's unlikely to ever appear in an ISA string (see the misaligned access performance, for example). The resulting interface looks a lot like what arm64 and x86 do, and will hopefully fit well into something like ACPI in the future. The actual user interface is a syscall, with a vDSO function in front of it. The vDSO function can answer some queries without a syscall at all, and falls back to the syscall for cases it doesn't have answers to. Currently we prepopulate it with an array of answers for all keys and a CPU set of "all CPUs". This can be adjusted as necessary to provide fast answers to the most common queries. An example series in glibc exposing this syscall and using it in an ifunc selector for memcpy can be found at [1]. I was asked about the performance delta between this and something like sysfs. I created a small test program and ran it on a Nezha D1 Allwinner board. Doing each operation 100000 times and dividing, these operations take the following amount of time: - open()+read()+close() of /sys/kernel/cpu_byteorder: 3.8us - access("/sys/kernel/cpu_byteorder", R_OK): 1.3us - riscv_hwprobe() vDSO and syscall: .0094us - riscv_hwprobe() vDSO with no syscall: 0.0091us These numbers get farther apart if we query multiple keys, as sysfs will scale linearly with the number of keys, where the dedicated syscall stays the same. To frame these numbers, I also did a tight fork/exec/wait loop, which I measured as 4.8ms. So doing 4 open/read/close operations is a delta of about 0.3%, versus a single vDSO call is a delta of essentially zero. [1] https://patchwork.ozlabs.org/project/glibc/list/?series=343050 * b4-shazam-merge: RISC-V: Add hwprobe vDSO function and data selftests: Test the new RISC-V hwprobe interface RISC-V: hwprobe: Support probing of misaligned access performance RISC-V: hwprobe: Add support for RISCV_HWPROBE_BASE_BEHAVIOR_IMA RISC-V: Add a syscall for HW probing RISC-V: Move struct riscv_cpuinfo to new header Link: https://lore.kernel.org/r/20230407231103.2622178-1-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-19RISC-V: hwprobe: Support probing of misaligned access performanceEvan Green1-0/+7
This allows userspace to select various routines to use based on the performance of misaligned access on the target hardware. Rather than adding DT bindings, this change taps into the alternatives mechanism used to probe CPU errata. Add a new function pointer alongside the vendor-specific errata_patch_func() that probes for desirable errata (otherwise known as "features"). Unlike the errata_patch_func(), this function is called on each CPU as it comes up, so it can save feature information per-CPU. The T-head C906 has fast unaligned access, both as defined by GCC [1], and in performing a basic benchmark, which determined that byte copies are >50% slower than a misaligned word copy of the same data size (source for this test at [2]): bytecopy size f000 count 50000 offset 0 took 31664899 us wordcopy size f000 count 50000 offset 0 took 5180919 us wordcopy size f000 count 50000 offset 1 took 13416949 us [1] https://github.com/gcc-mirror/gcc/blob/master/gcc/config/riscv/riscv.cc#L353 [2] https://pastebin.com/EPXvDHSW Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-5-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-19RISC-V: hwprobe: Add support for RISCV_HWPROBE_BASE_BEHAVIOR_IMAEvan Green1-0/+5
We have an implicit set of base behaviors that userspace depends on, which are mostly defined in various ISA specifications. Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-4-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-19RISC-V: Add a syscall for HW probingEvan Green2-0/+34
We don't have enough space for these all in ELF_HWCAP{,2} and there's no system call that quite does this, so let's just provide an arch-specific one to probe for hardware capabilities. This currently just provides m{arch,imp,vendor}id, but with the key-value pairs we can pass more in the future. Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-3-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-15RISC-V: KVM: Expose Zicboz to the guestAndrew Jones1-0/+1
Guests may use the cbo.zero instruction when the CPU has the Zicboz extension and the hypervisor sets henvcfg.CBZE. Add Zicboz support for KVM guests which may be enabled and disabled from KVM userspace using the ISA extension ONE_REG API. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20230224162631.405473-9-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-15RISC-V: KVM: Provide UAPI for Zicboz block sizeAndrew Jones1-0/+1
We're about to allow guests to use the Zicboz extension. KVM userspace needs to know the cache block size in order to properly advertise it to the guest. Provide a virtual config register for userspace to get it with the GET_ONE_REG API, but setting it cannot be supported, so disallow SET_ONE_REG. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20230224162631.405473-8-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>