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5 daysRISC-V: KVM: Fix inclusion of Smnpm in the guest ISA bitmapSamuel Holland
The Smnpm extension requires special handling because the guest ISA extension maps to a different extension (Ssnpm) on the host side. commit 1851e7836212 ("RISC-V: KVM: Allow Smnpm and Ssnpm extensions for guests") missed that the vcpu->arch.isa bit is based only on the host extension, so currently both KVM_RISCV_ISA_EXT_{SMNPM,SSNPM} map to vcpu->arch.isa[RISCV_ISA_EXT_SSNPM]. This does not cause any problems for the guest, because both extensions are force-enabled anyway when the host supports Ssnpm, but prevents checking for (guest) Smnpm in the SBI FWFT logic. Redefine kvm_isa_ext_arr to look up the guest extension, since only the guest -> host mapping is unambiguous. Factor out the logic for checking for host support of an extension, so this special case only needs to be handled in one place, and be explicit about which variables hold a host vs a guest ISA extension. Fixes: 1851e7836212 ("RISC-V: KVM: Allow Smnpm and Ssnpm extensions for guests") Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20250111004702.2813013-2-samuel.holland@sifive.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-04-04Merge tag 'riscv-for-linus-6.15-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - The sub-architecture selection Kconfig system has been cleaned up, the documentation has been improved, and various detections have been fixed - The vector-related extensions dependencies are now validated when parsing from device tree and in the DT bindings - Misaligned access probing can be overridden via a kernel command-line parameter, along with various fixes to misalign access handling - Support for relocatable !MMU kernels builds - Support for hpge pfnmaps, which should improve TLB utilization - Support for runtime constants, which improves the d_hash() performance - Support for bfloat16, Zicbom, Zaamo, Zalrsc, Zicntr, Zihpm - Various fixes, including: - We were missing a secondary mmu notifier call when flushing the tlb which is required for IOMMU - Fix ftrace panics by saving the registers as expected by ftrace - Fix a couple of stimecmp usage related to cpu hotplug - purgatory_start is now aligned as per the STVEC requirements - A fix for hugetlb when calculating the size of non-present PTEs * tag 'riscv-for-linus-6.15-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (65 commits) riscv: Add norvc after .option arch in runtime const riscv: Make sure toolchain supports zba before using zba instructions riscv/purgatory: 4B align purgatory_start riscv/kexec_file: Handle R_RISCV_64 in purgatory relocator selftests: riscv: fix v_exec_initval_nolibc.c riscv: Fix hugetlb retrieval of number of ptes in case of !present pte riscv: print hartid on bringup riscv: Add norvc after .option arch in runtime const riscv: Remove CONFIG_PAGE_OFFSET riscv: Support CONFIG_RELOCATABLE on riscv32 asm-generic: Always define Elf_Rel and Elf_Rela riscv: Support CONFIG_RELOCATABLE on NOMMU riscv: Allow NOMMU kernels to access all of RAM riscv: Remove duplicate CONFIG_PAGE_OFFSET definition RISC-V: errata: Use medany for relocatable builds dt-bindings: riscv: document vector crypto requirements dt-bindings: riscv: add vector sub-extension dependencies dt-bindings: riscv: d requires f RISC-V: add f & d extension validation checks RISC-V: add vector crypto extension validation checks ...
2025-03-20RISC-V: KVM: Optimize comments in kvm_riscv_vcpu_isa_disable_allowedChao Du
The comments for EXT_SVADE are a bit confusing. Clarify it. Signed-off-by: Chao Du <duchao@eswincomputing.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20250221025929.31678-1-duchao@eswincomputing.com Signed-off-by: Anup Patel <anup@brainfault.org>
2025-03-19RISC-V: KVM: Allow Zaamo/Zalrsc extensions for Guest/VMClément Léger
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zaamo/Zalrsc extensions for Guest/VM. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20240619153913.867263-5-cleger@rivosinc.com Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
2024-12-30RISC-V: KVM: Allow Ziccrse extension for Guest/VMQuan Zhou
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Ziccrse extension for Guest/VM. Signed-off-by: Quan Zhou <zhouquan@iscas.ac.cn> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/d10e746d165074174f830aa3d89bf3c92017acee.1732854096.git.zhouquan@iscas.ac.cn Signed-off-by: Anup Patel <anup@brainfault.org>
2024-12-30RISC-V: KVM: Allow Zabha extension for Guest/VMQuan Zhou
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zabha extension for Guest/VM. Signed-off-by: Quan Zhou <zhouquan@iscas.ac.cn> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/4074feb27819e23bab05b0fd6441a38bf0b6a5e2.1732854096.git.zhouquan@iscas.ac.cn Signed-off-by: Anup Patel <anup@brainfault.org>
2024-12-30RISC-V: KVM: Allow Svvptc extension for Guest/VMQuan Zhou
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Svvptc extension for Guest/VM. Signed-off-by: Quan Zhou <zhouquan@iscas.ac.cn> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/133509ffe5783b62cf95e8f675cc3e327bee402e.1732854096.git.zhouquan@iscas.ac.cn Signed-off-by: Anup Patel <anup@brainfault.org>
2024-11-27Merge tag 'kvm-riscv-6.13-2' of https://github.com/kvm-riscv/linux into HEADPaolo Bonzini
KVM/riscv changes for 6.13 part #2 - Svade and Svadu extension support for Host and Guest/VM
2024-11-21RISC-V: KVM: Add Svade and Svadu Extensions Support for Guest/VMYong-Xuan Wang
We extend the KVM ISA extension ONE_REG interface to allow VMM tools to detect and enable Svade and Svadu extensions for Guest/VM. Since the henvcfg.ADUE is read-only zero if the menvcfg.ADUE is zero, the Svadu extension is available for Guest/VM and the Svade extension is allowed to disabledonly when arch_has_hw_pte_young() is true. Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Samuel Holland <samuel.holland@sifive.com> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20240726084931.28924-4-yongxuan.wang@sifive.com Signed-off-by: Anup Patel <anup@brainfault.org>
2024-10-24RISC-V: KVM: Allow Smnpm and Ssnpm extensions for guestsSamuel Holland
The interface for controlling pointer masking in VS-mode is henvcfg.PMM, which is part of the Ssnpm extension, even though pointer masking in HS-mode is provided by the Smnpm extension. As a result, emulating Smnpm in the guest requires (only) Ssnpm on the host. The guest configures Smnpm through the SBI Firmware Features extension, which KVM does not yet implement, so currently the ISA extension has no visible effect on the guest, and thus it cannot be disabled. Ssnpm is configured using the senvcfg CSR within the guest, so that extension cannot be hidden from the guest without intercepting writes to the CSR. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20241016202814.4061541-10-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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 ...
2024-07-12Merge patch series "riscv: Apply Zawrs when available"Palmer Dabbelt
Andrew Jones <ajones@ventanamicro.com> says: Zawrs provides two instructions (wrs.nto and wrs.sto), where both are meant to allow the hart to enter a low-power state while waiting on a store to a memory location. The instructions also both wait an implementation-defined "short" duration (unless the implementation terminates the stall for another reason). The difference is that while wrs.sto will terminate when the duration elapses, wrs.nto, depending on configuration, will either just keep waiting or an ILL exception will be raised. Linux will use wrs.nto, so if platforms have an implementation which falls in the "just keep waiting" category (which is not expected), then it should _not_ advertise Zawrs in the hardware description. Like wfi (and with the same {m,h}status bits to configure it), when wrs.nto is configured to raise exceptions it's expected that the higher privilege level will see the instruction was a wait instruction, do something, and then resume execution following the instruction. For example, KVM does configure exceptions for wfi (hstatus.VTW=1) and therefore also for wrs.nto. KVM does this for wfi since it's better to allow other tasks to be scheduled while a VCPU waits for an interrupt. For waits such as those where wrs.nto/sto would be used, which are typically locks, it is also a good idea for KVM to be involved, as it can attempt to schedule the lock holding VCPU. This series starts with Christoph's addition of the riscv smp_cond_load_relaxed function which applies wrs.sto when available. That patch has been reworked to use wrs.nto and to use the same approach as Arm for the wait loop, since we can't have arbitrary C code between the load-reserved and the wrs. Then, hwprobe support is added (since the instructions are also usable from usermode), and finally KVM is taught about wrs.nto, allowing guests to see and use the Zawrs extension. We still don't have test results from hardware, and it's not possible to prove that using Zawrs is a win when testing on QEMU, not even when oversubscribing VCPUs to guests. However, it is possible to use KVM selftests to force a scenario where we can prove Zawrs does its job and does it well. [4] is a test which does this and, on my machine, without Zawrs it takes 16 seconds to complete and with Zawrs it takes 0.25 seconds. This series is also available here [1]. In order to use QEMU for testing a build with [2] is needed. In order to enable guests to use Zawrs with KVM using kvmtool, the branch at [3] may be used. [1] https://github.com/jones-drew/linux/commits/riscv/zawrs-v3/ [2] https://lore.kernel.org/all/20240312152901.512001-2-ajones@ventanamicro.com/ [3] https://github.com/jones-drew/kvmtool/commits/riscv/zawrs/ [4] https://github.com/jones-drew/linux/commit/cb2beccebcece10881db842ed69bdd5715cfab5d Link: https://lore.kernel.org/r/20240426100820.14762-8-ajones@ventanamicro.com * b4-shazam-merge: 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' Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-12KVM: riscv: Support guest wrs.ntoAndrew Jones
When a guest traps on wrs.nto, call kvm_vcpu_on_spin() to attempt to yield to the lock holding VCPU. Also extend the KVM ISA extension ONE_REG interface to allow KVM userspace to detect and enable the Zawrs extension for the Guest/VM. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20240426100820.14762-13-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-06-26RISC-V: KVM: Allow Zcmop extension for Guest/VMClément Léger
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zcmop extension for Guest/VM. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20240619113529.676940-16-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-06-26RISC-V: KVM: Allow Zca, Zcf, Zcd and Zcb extensions for Guest/VMClément Léger
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zca, Zcf, Zcd and Zcb extensions for Guest/VM. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20240619113529.676940-11-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-06-26RISC-V: KVM: Allow Zimop extension for Guest/VMClément Léger
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zimop extension for Guest/VM. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20240619113529.676940-5-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-31RISC-V: KVM: Fix incorrect reg_subtype labels in ↵Quan Zhou
kvm_riscv_vcpu_set_reg_isa_ext function In the function kvm_riscv_vcpu_set_reg_isa_ext, the original code used incorrect reg_subtype labels KVM_REG_RISCV_SBI_MULTI_EN/DIS. These have been corrected to KVM_REG_RISCV_ISA_MULTI_EN/DIS respectively. Although they are numerically equivalent, the actual processing will not result in errors, but it may lead to ambiguous code semantics. Fixes: 613029442a4b ("RISC-V: KVM: Extend ONE_REG to enable/disable multiple ISA extensions") Signed-off-by: Quan Zhou <zhouquan@iscas.ac.cn> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/ff1c6771a67d660db94372ac9aaa40f51e5e0090.1716429371.git.zhouquan@iscas.ac.cn Signed-off-by: Anup Patel <anup@brainfault.org>
2024-04-26RISC-V: KVM: Add perf sampling support for guestsAtish Patra
KVM enables perf for guest via counter virtualization. However, the sampling can not be supported as there is no mechanism to enabled trap/emulate scountovf in ISA yet. Rely on the SBI PMU snapshot to provide the counter overflow data via the shared memory. In case of sampling event, the host first sets the guest's LCOFI interrupt and injects to the guest via irq filtering mechanism defined in AIA specification. Thus, ssaia must be enabled in the host in order to use perf sampling in the guest. No other AIA dependency w.r.t kernel is required. Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Atish Patra <atishp@rivosinc.com> Link: https://lore.kernel.org/r/20240420151741.962500-15-atishp@rivosinc.com Signed-off-by: Anup Patel <anup@brainfault.org>
2024-03-25RISC-V: KVM: Remove second semicolonColin Ian King
There is a statement with two semicolons. Remove the second one, it is redundant. Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Signed-off-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20240315092914.2431214-1-colin.i.king@gmail.com
2024-03-06RISC-V: KVM: Allow Zacas extension for Guest/VMAnup Patel
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zacas 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>
2024-03-06RISC-V: KVM: Allow Ztso extension for Guest/VMAnup Patel
Extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Ztso 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>
2024-01-19RISC-V: KVM: Allow Zfa extension for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zfa 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>
2024-01-19RISC-V: KVM: Allow Zvfh[min] extensions for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zvfh[min] 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>
2024-01-19RISC-V: KVM: Allow Zihintntl extension for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zihintntl 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>
2024-01-19RISC-V: KVM: Allow Zfh[min] extensions for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zfh[min] 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>
2024-01-19RISC-V: KVM: Allow vector crypto extensions for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable vector crypto extensions for Guest/VM. This includes extensions Zvbb, Zvbc, Zvkb, Zvkg, Zvkned, Zvknha, Zvknhb, Zvksed, Zvksh, and Zvkt. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2024-01-19RISC-V: KVM: Allow scalar crypto extensions for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable scalar crypto extensions for Guest/VM. This includes extensions Zbkb, Zbkc, Zbkx, Zknd, Zkne, Zknh, Zkr, Zksed, Zksh, and Zkt. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2024-01-19RISC-V: KVM: Allow Zbc extension for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zbc 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>
2023-12-30RISC-V: KVM: Add support for SBI STA registersAndrew Jones
KVM userspace needs to be able to save and restore the steal-time shared memory address. Provide the address through the get/set-one-reg interface with two ulong-sized SBI STA extension registers (lo and hi). 64-bit KVM userspace must not set the hi register to anything other than zero and is allowed to completely neglect saving/restoring it. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-12-30RISC-V: KVM: Add support for SBI extension registersAndrew Jones
Some SBI extensions have state that needs to be saved / restored when migrating the VM. Provide a get/set-one-reg register type for SBI extension registers. Each SBI extension that uses this type will have its own subtype. There are currently no subtypes defined. The next patch introduces the first one. Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-12-29RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()Anup Patel
The indentation of "break" in kvm_riscv_vcpu_set_reg_csr() is inconsistent hence let us fix it. Fixes: c04913f2b54e ("RISCV: KVM: Add sstateen0 to ONE_REG") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202312190719.kBuYl6oJ-lkp@intel.com/ Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-12-29RISC-V: KVM: add vector registers and CSRs in KVM_GET_REG_LISTDaniel Henrique Barboza
Add all vector registers and CSRs (vstart, vl, vtype, vcsr, vlenb) in get-reg-list. Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-12-29RISC-V: KVM: Make SBI uapi consistent with ISA uapiAndrew Jones
When an SBI extension cannot be enabled, that's a distinct state vs. enabled and disabled. Modify enum kvm_riscv_sbi_ext_status to accommodate it, which allows KVM userspace to tell the difference in state too, as the SBI extension register will disappear when it cannot be enabled, i.e. accesses to it return ENOENT. get-reg-list is updated as well to only add SBI extension registers to the list which may be enabled. Returning ENOENT for SBI extension registers which cannot be enabled makes them consistent with ISA extension registers. Any SBI extensions which were enabled by default are still enabled by default, if they can be enabled at all. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-12-29RISC-V: KVM: Don't add SBI multi regs in get-reg-listAndrew Jones
The multi regs are derived from the single registers. Only list the single registers in get-reg-list. This also makes the SBI extension register listing consistent with the ISA extension register listing. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Haibo Xu <haibo1.xu@intel.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-11-10Merge tag 'riscv-for-linus-6.7-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 handling misaligned accesses in S-mode - Probing for misaligned access support is now properly cached and handled in parallel - PTDUMP now reflects the SW reserved bits, as well as the PBMT and NAPOT extensions - Performance improvements for TLB flushing - Support for many new relocations in the module loader - Various bug fixes and cleanups * tag 'riscv-for-linus-6.7-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) riscv: Optimize bitops with Zbb extension riscv: Rearrange hwcap.h and cpufeature.h drivers: perf: Do not broadcast to other cpus when starting a counter drivers: perf: Check find_first_bit() return value of: property: Add fw_devlink support for msi-parent RISC-V: Don't fail in riscv_of_parent_hartid() for disabled HARTs riscv: Fix set_memory_XX() and set_direct_map_XX() by splitting huge linear mappings riscv: Don't use PGD entries for the linear mapping RISC-V: Probe misaligned access speed in parallel RISC-V: Remove __init on unaligned_emulation_finish() RISC-V: Show accurate per-hart isa in /proc/cpuinfo RISC-V: Don't rely on positional structure initialization riscv: Add tests for riscv module loading riscv: Add remaining module relocations riscv: Avoid unaligned access when relocating modules riscv: split cache ops out of dma-noncoherent.c riscv: Improve flush_tlb_kernel_range() riscv: Make __flush_tlb_range() loop over pte instead of flushing the whole tlb riscv: Improve flush_tlb_range() for hugetlb pages riscv: Improve tlb_flush() ...
2023-11-09riscv: Rearrange hwcap.h and cpufeature.hXiao Wang
Now hwcap.h and cpufeature.h are mutually including each other, and most of the variable/API declarations in hwcap.h are implemented in cpufeature.c, so, it's better to move them into cpufeature.h and leave only macros for ISA extension logical IDs in hwcap.h. BTW, the riscv_isa_extension_mask macro is not used now, so this patch removes it. Suggested-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Xiao Wang <xiao.w.wang@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20231031064553.2319688-2-xiao.w.wang@intel.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-10-12RISC-V: KVM: Allow Zicond extension for Guest/VMAnup Patel
We extend the KVM ISA extension ONE_REG interface to allow KVM user space to detect and enable Zicond 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>
2023-10-12RISCV: KVM: Add sstateen0 to ONE_REGMayuresh Chitale
Add support for sstateen0 CSR to the ONE_REG interface to allow its access from user space. Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-10-12RISC-V: KVM: Enable Smstateen accessesMayuresh Chitale
Configure hstateen0 register so that the AIA state and envcfg are accessible to the vcpus. This includes registers such as siselect, sireg, siph, sieh and all the IMISC registers. Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-09-21RISC-V: KVM: Fix riscv_vcpu_get_isa_ext_single() for missing extensionsAnup Patel
The riscv_vcpu_get_isa_ext_single() should fail with -ENOENT error when corresponding ISA extension is not available on the host. Fixes: e98b1085be79 ("RISC-V: KVM: Factor-out ONE_REG related code to its own source file") 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>
2023-09-21RISC-V: KVM: Fix KVM_GET_REG_LIST API for ISA_EXT registersAnup Patel
The ISA_EXT registers to enabled/disable ISA extensions for VCPU are always available when underlying host has the corresponding ISA extension. The copy_isa_ext_reg_indices() called by the KVM_GET_REG_LIST API does not align with this expectation so let's fix it. Fixes: 031f9efafc08 ("KVM: riscv: Add KVM_GET_REG_LIST API support") 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>
2023-08-09KVM: riscv: Add KVM_GET_REG_LIST API supportHaibo Xu
KVM_GET_REG_LIST API will return all registers that are available to KVM_GET/SET_ONE_REG APIs. It's very useful to identify some platform regression issue during VM migration. Since this API was already supported on arm64, it is straightforward to enable it on riscv with similar code structure. Signed-off-by: Haibo Xu <haibo1.xu@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-08-08RISC-V: KVM: Improve vector save/restore functionsAndrew Jones
Make two nonfunctional changes to the vector get/set vector reg functions and their supporting function for simplification and readability. The first is to not pass KVM_REG_RISCV_VECTOR, but rather integrate it directly into the masking. The second is to rename reg_val to reg_addr where and address is used instead of a value. Also opportunistically touch up some of the code formatting for a third nonfunctional change. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-08-08RISC-V: KVM: avoid EBUSY when writing the same isa_ext valDaniel Henrique Barboza
riscv_vcpu_set_isa_ext_single() will prevent any write of isa_ext regs if the vcpu already started spinning. But if there's no extension state (enabled/disabled) made by the userspace, there's no need to -EBUSY out - we can treat the operation as a no-op. zicbom/zicboz_block_size, ISA config reg and mvendorid/march/mimpid already works in a more permissive manner w.r.t userspace writes being a no-op, so let's do the same with isa_ext writes. 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: avoid EBUSY when writing the same machine ID valDaniel Henrique Barboza
Right now we do not allow any write in mvendorid/marchid/mimpid if the vcpu already started, preventing these regs to be changed. However, if userspace doesn't change them, an alternative is to consider the reg write a no-op and avoid erroring out altogether. Userpace can then be oblivious about KVM internals if no changes were intended in the first place. Allow the same form of 'lazy writing' that registers such as zicbom/zicboz_block_size supports: avoid erroring out if userspace makes no changes in mvendorid/marchid/mimpid during reg write. 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: avoid EBUSY when writing same ISA valDaniel Henrique Barboza
kvm_riscv_vcpu_set_reg_config() will return -EBUSY if the ISA config reg is being written after the VCPU ran at least once. The same restriction isn't placed in kvm_riscv_vcpu_get_reg_config(), so there's a chance that we'll -EBUSY out on an ISA config reg write even if the userspace intended no changes to it. We'll allow the same form of 'lazy writing' that registers such as zicbom/zicboz_block_size supports: avoid erroring out if userspace made no changes to the ISA config reg. 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: use EBUSY when !vcpu->arch.ran_atleast_onceDaniel Henrique Barboza
vcpu_set_reg_config() and vcpu_set_reg_isa_ext() is throwing an EOPNOTSUPP error when !vcpu->arch.ran_atleast_once. In similar cases we're throwing an EBUSY error, like in mvendorid/marchid/mimpid set_reg(). EOPNOTSUPP has a conotation of finality. EBUSY is more adequate in this case since its a condition/error related to the vcpu lifecycle. Change these EOPNOTSUPP instances to EBUSY. Suggested-by: Andrew Jones <ajones@ventanamicro.com> 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: do not EOPNOTSUPP in set_one_reg() zicbo(m|z)Daniel Henrique Barboza
zicbom_block_size and zicboz_block_size have a peculiar API: they can be read via get_one_reg() but any write will return a EOPNOTSUPP. It makes sense to return a 'not supported' error since both values can't be changed, but as far as userspace goes they're regs that are throwing the same EOPNOTSUPP error even if they were read beforehand via get_one_reg(), even if the same read value is being written back. EOPNOTSUPP is also returned even if ZICBOM/ZICBOZ aren't enabled in the host. Change both to work more like their counterparts in get_one_reg() and return -ENOENT if their respective extensions aren't available. After that, check if the userspace is written a valid value (i.e. the host value). Throw an -EINVAL if that's not case, let it slide otherwise. This allows both regs to be read/written by userspace in a 'lazy' manner, as long as the userspace doesn't change the reg vals. Suggested-by: Andrew Jones <ajones@ventanamicro.com> 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: use ENOENT in *_one_reg() when extension is unavailableDaniel Henrique Barboza
Following a similar logic as the previous patch let's minimize the EINVAL usage in *_one_reg() APIs by using ENOENT when an extension that implements the reg is not available. For consistency we're also replacing an EOPNOTSUPP instance that should be an ENOENT since it's an "extension is not available" error. 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: return ENOENT in *_one_reg() when reg is unknownDaniel Henrique Barboza
get_one_reg() and set_one_reg() are returning EINVAL errors for almost everything: if a reg doesn't exist, if a reg ID is malformatted, if the associated CPU extension that implements the reg isn't present in the host, and for set_one_reg() if the value being written is invalid. This isn't wrong according to the existing KVM API docs (EINVAL can be used when there's no such register) but adding more ENOENT instances will make easier for userspace to understand what went wrong. Existing userspaces can be affected by this error code change. We checked a few. As of current upstream code, crosvm doesn't check for any particular errno code when using kvm_(get|set)_one_reg(). Neither does QEMU. rust-vmm doesn't have kvm-riscv support yet. Thus we have a good chance of changing these error codes now while the KVM RISC-V ecosystem is still new, minimizing user impact. Change all get_one_reg() and set_one_reg() implementations to return -ENOENT at all "no such register" cases. Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>