From patchwork Thu May 18 16:19:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Chiu X-Patchwork-Id: 13247080 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 49DBBC7EE2A for ; Thu, 18 May 2023 16:20:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=aIQ8hFpSDuIqYMEYwWXY9/UZu1puUBYH+LEDL/VyC5k=; b=gJeC7y3PRjz29Q IJ4m60uI9/qnDumViYUkkqAHagon9ZWkDXAg47YR5A3iUY4ajyJ2HQsbyzN1gjpQXK1zZ2h5fPh0x yJTIW/T+mCBbbxKcAVxSlU0rptns17CMzfYJiR6gLVDZdubzXzroCwdYT0ZmlcyZBL1pP9N3ZH2s5 ooHavnKGDktc+b1e2NRf6AY8x8gl+ZzNBI2ruT8YBhf7mHT/GZ8Ogo+WmzpqtrSostssbj1GOW/LY +/3gCBWqGd8MzGAK2OYn9Rv31yibYMeh2oQje1Fm7mxl3YMPjPZFePL8m0zStnyBw+kkiModG6kfD AMpuXuEoJeFQ4JzY/lNA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pzgMS-00DQlx-2x; Thu, 18 May 2023 16:20:16 +0000 Received: from mail-pf1-x42e.google.com ([2607:f8b0:4864:20::42e]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pzgMO-00DQjC-2m for linux-riscv@lists.infradead.org; Thu, 18 May 2023 16:20:15 +0000 Received: by mail-pf1-x42e.google.com with SMTP id d2e1a72fcca58-643846c006fso2237812b3a.0 for ; Thu, 18 May 2023 09:20:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; t=1684426809; x=1687018809; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=QkAP+MCzid27lQKKAKPDtQpx75fhMpiVU9fXRekdLpM=; b=XFoc/VQGrdaOTqbwR2Vg3vCogNIeAQQnwV8YEZLCEIGUgy0WcxsagYBaFxKByr84/E 6uXXZB137+WF/j7A3eRQ9QzuI0xPknz73Q8+rHqXYp8tHGyAKTYTizbpO8SWkdjkfUo6 kt5XWI8jQi7HhtmW29mqbtzRmlBONGXdsLSL5Vobhie0Kwo9De1dTIirYNcu1/zDKLp4 j17cvB1mIPG0O88ezpgLZTuXCpIVIr35n3dHsD2SRWOeiwgCwbUWGa2nPBQeclQEN94/ 1umts+pjtSwyqwQuBHF1/h+ParHXmrI9rbftJ2hu8VrCNiPabB/HkYqkbpfSVTzHsadT u0DQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684426809; x=1687018809; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=QkAP+MCzid27lQKKAKPDtQpx75fhMpiVU9fXRekdLpM=; b=X9/pjwBtBBYVps8sYztyVKL39PFp5IZfXaVI/YsF7AGjnTEJamkYUDpmW44UrowbjU BeH0z6WsXXZiuunvROTxnT4ishlbzWnmsPgAo9zSYnYo1H8pyZzjPQJE9pPYAFkBcfvI GLQ11ZDgO9K3ny93ZsukUTG9wznikbhczMvORmrxDWfArFgdHDU024Drk6nxL7mRSgqd eJZYGkJBVk54pW2yPp4afm+xz+Qy+nH0A3GipC0TJDH3l2GncfodrF+tf6eubVTVI18V /n0P3XALjcChohRDmLGhL77fVExFy6R9vTHF99MXjXlXlo5h7tgmEuB0b2+M2N5ETpu6 rOVw== X-Gm-Message-State: AC+VfDzBwDh/5dIJ3gqmTNANpnI4NWRKDgLY7iXMtVWtB3bWf8FMTh73 pw4mZf/TaihQ+2yNxiH8ZrYUT54ie6SgWoo8nA/gZm79re0wEAtVsoO1RMc7YLE+Xkv9eYTd0ya HxCFt87J9meapuObKk0hNyR9utrsWat+t23JgFwV8AvG9Clm89o2Gr4BDggVjXixuRemtrEuIeQ 5UbC+QnAHNByvT+5M= X-Google-Smtp-Source: ACHHUZ6evOWqHzjBY1VisM9AARicYsq+twqQSS2M5FR2J99qSIS9g5lLhNdFkcXzj6KENKCxC7llNA== X-Received: by 2002:a05:6a00:2446:b0:645:fc7b:63d6 with SMTP id d6-20020a056a00244600b00645fc7b63d6mr4512980pfj.6.1684426808999; Thu, 18 May 2023 09:20:08 -0700 (PDT) Received: from hsinchu25.internal.sifive.com (59-124-168-89.hinet-ip.hinet.net. [59.124.168.89]) by smtp.gmail.com with ESMTPSA id x23-20020a62fb17000000b006414b2c9efasm1515862pfm.123.2023.05.18.09.20.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 May 2023 09:20:07 -0700 (PDT) From: Andy Chiu To: linux-riscv@lists.infradead.org, palmer@dabbelt.com, anup@brainfault.org, atishp@atishpatra.org, kvm-riscv@lists.infradead.org, kvm@vger.kernel.org Cc: vineetg@rivosinc.com, greentime.hu@sifive.com, guoren@linux.alibaba.com, Andy Chiu , Paul Walmsley , Albert Ou , Nathan Chancellor , Nick Desaulniers , Tom Rix Subject: [PATCH -next v20 00/26] riscv: Add vector ISA support Date: Thu, 18 May 2023 16:19:23 +0000 Message-Id: <20230518161949.11203-1-andy.chiu@sifive.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230518_092012_907221_8E659A99 X-CRM114-Status: GOOD ( 30.71 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org This patchset is implemented based on vector 1.0 spec to add vector support in riscv Linux kernel. There are some assumptions for this implementations. 1. We assume all harts has the same ISA in the system. 2. We disable vector in both kernel and user space [1] by default. Only enable an user's vector after an illegal instruction trap where it actually starts executing vector (the first-use trap [2]). 3. We detect "riscv,isa" to determine whether vector is support or not. We defined a new structure __riscv_v_ext_state in struct thread_struct to save/restore the vector related registers. It is used for both kernel space and user space. - In kernel space, the datap pointer in __riscv_v_ext_state will be allocated to save vector registers. - In user space, - In signal handler of user space, the structure is placed right after __riscv_ctx_hdr, which is embedded in fp reserved aera. This is required to avoid ABI break [2]. And datap points to the end of __riscv_v_ext_state. - In ptrace, the data will be put in ubuf in which we use riscv_vr_get()/riscv_vr_set() to get or set the __riscv_v_ext_state data structure from/to it, datap pointer would be zeroed and vector registers will be copied to the address right after the __riscv_v_ext_state structure in ubuf. This patchset is rebased to v6.4-rc1 and it is tested by running several vector programs simultaneously. It delivers signals correctly in a test where we can see a valid ucontext_t in a signal handler, and a correct V context returing back from it. And the ptrace interface is tested by PTRACE_{GET,SET}REGSET. Lastly, KVM is tested by running above tests in a guest using the same kernel image. All tests are done on an rv64gcv virt QEMU. Additionally, to work with the potential impact on ABI stability mentioned at [4], we implement prctl(), and a sysctl interfaces to control userspace Vector for compatibility. The prctl interface can be tested by kselftest, which is provided at the end of the series. The default is to enable Vector for userspace given that it is likely a theoretical case for ABI break, and that it provides a chance to find breakages (if any) early and developers to play around with V[5]. Source tree: https://github.com/sifive/riscv-linux/tree/riscv/for-next/vector-v20 Links: - [1] https://lore.kernel.org/all/20220921214439.1491510-17-stillson@rivosinc.com/ - [2] https://lore.kernel.org/all/73c0124c-4794-6e40-460c-b26df407f322@rivosinc.com/T/#u - [3] https://lore.kernel.org/all/20230128082847.3055316-1-apatel@ventanamicro.com/ - [4] https://inbox.sourceware.org/libc-alpha/87leinq5wg.fsf@all.your.base.are.belong.to.us/ - [5] https://lore.kernel.org/all/mhng-8554b236-c9d4-4590-8941-ed7ca5316d18@palmer-ri-x1c9a/ Updated patches: 2, 3, 11, 20, 21, 23, 24 New patches: 25, 26 Unchanged patches: 1, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 17, 18, 19, 22 Reviewed-by: Conor Dooley --- Changelog V20 - Add .gitignore into hwprobe (patch 26) - Implement test for prctl and fix issues (patch 20, 25) - Fix compile error with allmodconfig (patch 20). - Check elf_hwcap in first-use trap (patch 11). - Refine code (patch 11, 20, 21, 23, 24) - Properly add V entry into hwprobe (patch 3). - Fix typos (patch 3, 24) - Use "_unlikely" to detect V since there is no public available hw that supports it (patch 2). Changelog V19 - Rebase to the latest -next branch (at 6.4-rc1 ac9a786). Solve conflicts at patch 14, 15, and 19. - Add a sysctl, and prctl intefaces for userspace Vector control, and a document for it. (patch 20, 21, 24) - Add a Kconfig RISCV_V_DISABLE to set the default value of userspace Vector enablement status at compile-time. (patch 23) - Allow hwprobe interface to probe Vector. (patch 3) - Fix typos and commit msg at patch 6 and 8. Changelog V18 - Rebase to the latest -next branch (at 9c2598d) - patch 7: Detect inconsistent VLEN setup on an SMP system (Heiko). - patch 10: Add blank lines (Heiko) - patch 10: Return immediately in insn_is_vector() if an insn matches (Heiko) - patch 11: Use sizeof(vstate->datap) instead of sizeof(void*) (Eike) Changelog V17 - Rebase to the latest -next branch (at e45d6a5): - Solve conflicts at 9 and 13 due to generic entry - Use generic entry in do_trap_insn_illegal() trap handler Changelog V16 - Rebase to the latest for-next (at 4b74077): - Solve conflicts at 7, and 17 - Use as-instr to detect if assembler supports .option arch directive and remove dependency from GAS, for both ZBB and V. - Cleanup code in KVM vector - Address issue reported by sparse - Refine code: - Fix a mixed-use of space/tab - Remove new lines at the end of file Changelog V15 - Rebase to risc-v -next (v6.3-rc1) - Make V depend on FD in Kconfig according to the spec and shut off v properly. - Fix a syntax error for clang build. But mark RISCV_ISA_V GAS only due to https://reviews.llvm.org/D123515 - Use scratch reg in inline asm instead of t4. - Refine code. - Cleanup per-patch changelogs. Changelog V14 - Rebase to risc-v -next (v6.2-rc7) - Use TOOLCHAIN_HAS_V to detect if we can enable Vector. And refine KBUILD_CFLAGS to remove v from default compile option. - Drop illegal instruction handling patch in kvm and leave it to a independent series[3]. The series has merged into 6.3-rc1 - Move KVM_RISCV_ISA_EXT_V to the end of enum to prevent potential ABI breaks. - Use PT_SIZE_ON_STACK instead of PT_SIZE to fit alignment. Also, remove panic log from v13 (15/19) because it is no longer relevant. - Rewrite insn_is_vector for better structuring (change if-else chain to a switch) - Fix compilation error in the middle of the series - Validate size of the alternative signal frame if V is enabled whenever: - The user call sigaltstack to update altstack - A signal is being delivered - Rename __riscv_v_state to __riscv_v_ext_state. - Add riscv_v_ prefix and rename rvv appropriately - Organize riscv_v_vsize setup code into vector.c - Address the issue mentioned by Heiko on !FPU case - Honor orignal authors that got changed accidentally in v13 4,5,6 Changelog V13 - Rebase to latest risc-v next (v6.2-rc1) - vineetg: Re-organize the series to comply with bisect-ability - andy.chiu: Improve task switch with inline assembly - Re-structure the signal frame to avoid user ABI break. - Implemnt first-use trap and drop prctl for per-task V state enablement. Also, redirect this trap from hs to vs for kvm setup. - Do not expose V context in ptrace/sigframe until the task start using V. But still reserve V context for size ofsigframe reported by auxv. - Drop the kernel mode vector and leave it to another (future) series. Changelog V12 (Chris) - rebases to some point after v5.18-rc6 - add prctl to control per-process V state Chnagelog V10 - Rebase to v5.18-rc6 - Merge several patches - Refine codes - Fix bugs - Add kvm vector support Changelog V9 - Rebase to v5.15 - Merge several patches - Refine codes - Fix a kernel panic issue Changelog V8 - Rebase to v5.14 - Refine struct __riscv_v_ext_state with struct __riscv_ctx_hdr - Refine has_vector into a static key - Defined __reserved space in struct sigcontext for vector and future extensions Changelog V7 - Add support for kernel mode vector - Add vector extension XOR implementation - Optimize task switch codes of vector - Allocate space for vector registers in start_thread() - Fix an illegal instruction exception when accessing vlenb - Optimize vector registers initialization - Initialize vector registers with proper vsetvli then it can work normally - Refine ptrace porting due to generic API changed - Code clean up Changelog V6 - Replace vle.v/vse.v instructions with vle8.v/vse8.v based on 0.9 spec - Add comments based on mailinglist feedback - Fix rv32 build error Changelog V5 - Using regset_size() correctly in generic ptrace - Fix the ptrace porting - Fix compile warning Changelog V4 - Support dynamic vlen - Fix bugs: lazy save/resotre, not saving vtype - Update VS bit offset based on latest vector spec - Add new vector csr based on latest vector spec - Code refine and removed unused macros Changelog V3 - Rebase linux-5.6-rc3 and tested with qemu - Seperate patches with Anup's advice - Give out a ABI puzzle with unlimited vlen Changelog V2 - Fixup typo "vecotr, fstate_save->vstate_save". - Fixup wrong saved registers' length in vector.S. - Seperate unrelated patches from this one. Andy Chiu (10): riscv: hwprobe: Add support for probing V in RISCV_HWPROBE_KEY_IMA_EXT_0 riscv: Allocate user's vector context in the first-use trap riscv: signal: check fp-reserved words unconditionally riscv: signal: validate altstack to reflect Vector riscv: Add prctl controls for userspace vector management riscv: Add sysctl to set the default vector rule for new processes riscv: detect assembler support for .option arch riscv: Add documentation for Vector selftests: Test RISC-V Vector prctl interface selftests: add .gitignore file for RISC-V hwprobe Greentime Hu (9): riscv: Add new csr defines related to vector extension riscv: Clear vector regfile on bootup riscv: Introduce Vector enable/disable helpers riscv: Introduce riscv_v_vsize to record size of Vector context riscv: Introduce struct/helpers to save/restore per-task Vector state riscv: Add task switch support for vector riscv: Add ptrace vector support riscv: signal: Add sigcontext save/restore for vector riscv: prevent stack corruption by reserving task_pt_regs(p) early Guo Ren (4): riscv: Rename __switch_to_aux() -> fpu riscv: Extending cpufeature.c to detect V-extension riscv: Disable Vector Instructions for kernel itself riscv: Enable Vector code to be built Vincent Chen (3): riscv: signal: Report signal frame size to userspace via auxv riscv: kvm: Add V extension to KVM ISA riscv: KVM: Add vector lazy save/restore support Documentation/riscv/hwprobe.rst | 3 + Documentation/riscv/index.rst | 1 + Documentation/riscv/vector.rst | 120 ++++++++ arch/riscv/Kconfig | 39 ++- arch/riscv/Makefile | 6 +- arch/riscv/include/asm/csr.h | 18 +- arch/riscv/include/asm/elf.h | 9 + arch/riscv/include/asm/hwcap.h | 1 + arch/riscv/include/asm/insn.h | 29 ++ arch/riscv/include/asm/kvm_host.h | 2 + arch/riscv/include/asm/kvm_vcpu_vector.h | 82 +++++ arch/riscv/include/asm/processor.h | 16 + arch/riscv/include/asm/switch_to.h | 9 +- arch/riscv/include/asm/thread_info.h | 3 + arch/riscv/include/asm/vector.h | 184 ++++++++++++ arch/riscv/include/uapi/asm/auxvec.h | 1 + arch/riscv/include/uapi/asm/hwcap.h | 1 + arch/riscv/include/uapi/asm/hwprobe.h | 1 + arch/riscv/include/uapi/asm/kvm.h | 8 + arch/riscv/include/uapi/asm/ptrace.h | 39 +++ arch/riscv/include/uapi/asm/sigcontext.h | 16 +- arch/riscv/kernel/Makefile | 1 + arch/riscv/kernel/cpufeature.c | 13 + arch/riscv/kernel/entry.S | 6 +- arch/riscv/kernel/head.S | 41 ++- arch/riscv/kernel/process.c | 19 ++ arch/riscv/kernel/ptrace.c | 70 +++++ arch/riscv/kernel/setup.c | 3 + arch/riscv/kernel/signal.c | 220 ++++++++++++-- arch/riscv/kernel/smpboot.c | 7 + arch/riscv/kernel/sys_riscv.c | 4 + arch/riscv/kernel/traps.c | 26 +- arch/riscv/kernel/vector.c | 280 ++++++++++++++++++ arch/riscv/kvm/Makefile | 1 + arch/riscv/kvm/vcpu.c | 25 ++ arch/riscv/kvm/vcpu_vector.c | 186 ++++++++++++ include/uapi/linux/elf.h | 1 + include/uapi/linux/prctl.h | 11 + kernel/sys.c | 12 + tools/testing/selftests/riscv/Makefile | 2 +- .../selftests/riscv/hwprobe/.gitignore | 1 + .../testing/selftests/riscv/vector/.gitignore | 2 + tools/testing/selftests/riscv/vector/Makefile | 15 + .../riscv/vector/vstate_exec_nolibc.c | 111 +++++++ .../selftests/riscv/vector/vstate_prctl.c | 189 ++++++++++++ 45 files changed, 1784 insertions(+), 50 deletions(-) create mode 100644 Documentation/riscv/vector.rst create mode 100644 arch/riscv/include/asm/kvm_vcpu_vector.h create mode 100644 arch/riscv/include/asm/vector.h create mode 100644 arch/riscv/kernel/vector.c create mode 100644 arch/riscv/kvm/vcpu_vector.c create mode 100644 tools/testing/selftests/riscv/hwprobe/.gitignore create mode 100644 tools/testing/selftests/riscv/vector/.gitignore create mode 100644 tools/testing/selftests/riscv/vector/Makefile create mode 100644 tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c create mode 100644 tools/testing/selftests/riscv/vector/vstate_prctl.c