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[2620:137:e000::1:20]) by mx.google.com with ESMTP id y64-20020a636443000000b0054fd88c3598si23651173pgb.35.2023.07.05.12.33.59; Wed, 05 Jul 2023 12:34:12 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@rivosinc-com.20221208.gappssmtp.com header.s=20221208 header.b=B5MuAnjy; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232942AbjGETB3 (ORCPT + 99 others); Wed, 5 Jul 2023 15:01:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232371AbjGETBZ (ORCPT ); Wed, 5 Jul 2023 15:01:25 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F8741BDD for ; Wed, 5 Jul 2023 12:00:56 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id d9443c01a7336-1b7e6512973so40604215ad.3 for ; Wed, 05 Jul 2023 12:00:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20221208.gappssmtp.com; s=20221208; t=1688583646; x=1691175646; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=YwDbFN4IMu/IT2sUnJpiyfq5VoW3RyrrIlVKWP8Zp3M=; b=B5MuAnjyPA5HWnw/0ZMD7sikNOclxpF4lGSvciWQB87w4rFYSUNfLNK+HsQp492Rf+ ZxPO1vU+712n7WlePRMhOn6SczHHo9fE6HIJLL8ZyJ/POLpUb9mOET4MxYE1D1KL66+R yc7XK/MLgV48J/rmUICg/JfoMi8RwOcb8Rdc0L6L7JA3HWXsHZEe5vqnDO4wpHtksNG0 6hykpWJqcBzzZvBlwkUnF6EpCUytPeXyckLHmbzX+YnvS2NJrlzxgyDFU30U93nh8Azf WSn1iuqn7dcZTohfbd3Vdke/R26c1Z9YtPFh/+P4RJkaVsr6lp0+b0KcwUXVO3bdjKSZ UYyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688583646; x=1691175646; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=YwDbFN4IMu/IT2sUnJpiyfq5VoW3RyrrIlVKWP8Zp3M=; b=f99hSI8pZEA+UMvYu0PmnYAgzyj0yl2JeY/aPp5VZ5meUdkQioBNNno+7Vn6LErVdL k/34sZq3R81/edu7icU2vPqiYkEdDwXvoD4y6BNWyGO9+894pk9GihtUrexwJDPzu0gR NUotrGllnqPn+anQtM5Ku15bsH+M5/xf4mG4/nluM+VN2QyMQt9tEWnjZYBXi7w+QxUa vmeoz2ljjpdQgIZi2kmwODRXu9Tf8lO7aylxb6dHdT4lBMBo9+KvRcAGwFikJe3Blr4r UgmgKHZT23MoW5HIIekSPNP3dypCZTDd4vnTfdtatxYyOq2eQ1Av9sU4x9rX2ifncvW5 3Z4Q== X-Gm-Message-State: ABy/qLaeiqmK/R+XPOpu58SaeSD7YEhTZH4FbEsl9rk0CCGd1oN6Kgun 4LuEbPevxj1pHwwRHnYIPCj6Ng== X-Received: by 2002:a17:903:495:b0:1b8:a372:9c25 with SMTP id jj21-20020a170903049500b001b8a3729c25mr3944409plb.9.1688583646025; Wed, 05 Jul 2023 12:00:46 -0700 (PDT) Received: from charlie.ba.rivosinc.com ([66.220.2.162]) by smtp.gmail.com with ESMTPSA id d7-20020a170902aa8700b001b0358848b0sm19323359plr.161.2023.07.05.12.00.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Jul 2023 12:00:45 -0700 (PDT) From: Charlie Jenkins To: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Cc: charlie@rivosinc.com, conor@kernel.org, paul.walmsley@sifive.com, palmer@rivosinc.com, aou@eecs.berkeley.edu, anup@brainfault.org, konstantin@linuxfoundation.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, mick@ics.forth.gr, jrtc27@jrtc27.com Subject: [RESEND PATCH v3 1/2] RISC-V: mm: Restrict address space for sv39,sv48,sv57 Date: Wed, 5 Jul 2023 11:59:41 -0700 Message-ID: <20230705190002.384799-2-charlie@rivosinc.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230705190002.384799-1-charlie@rivosinc.com> References: <20230705190002.384799-1-charlie@rivosinc.com> MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1770610388345183277?= X-GMAIL-MSGID: =?utf-8?q?1770610388345183277?= Make sv48 the default address space for mmap as some applications currently depend on this assumption. The RISC-V specification enforces that bits outside of the virtual address range are not used, so restricting the size of the default address space as such should be temporary. A hint address passed to mmap will cause the largest address space that fits entirely into the hint to be used. If the hint is less than or equal to 1<<38, an sv39 address will be used. An exception is that if the hint address is 0, then a sv48 address will be used. After an address space is completely full, the next smallest address space will be used. Signed-off-by: Charlie Jenkins --- arch/riscv/include/asm/elf.h | 2 +- arch/riscv/include/asm/pgtable.h | 13 +++++++++++- arch/riscv/include/asm/processor.h | 34 ++++++++++++++++++++++++------ 3 files changed, 40 insertions(+), 9 deletions(-) diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index 30e7d2455960..1b57f13a1afd 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -49,7 +49,7 @@ extern bool compat_elf_check_arch(Elf32_Ehdr *hdr); * the loader. We need to make sure that it is out of the way of the program * that it will "exec", and that there is sufficient room for the brk. */ -#define ELF_ET_DYN_BASE ((TASK_SIZE / 3) * 2) +#define ELF_ET_DYN_BASE ((DEFAULT_MAP_WINDOW / 3) * 2) #ifdef CONFIG_64BIT #ifdef CONFIG_COMPAT diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 75970ee2bda2..752e210c7547 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -57,18 +57,29 @@ #define MODULES_END (PFN_ALIGN((unsigned long)&_start)) #endif + /* * Roughly size the vmemmap space to be large enough to fit enough * struct pages to map half the virtual address space. Then * position vmemmap directly below the VMALLOC region. */ #ifdef CONFIG_64BIT +#define VA_BITS_SV39 39 +#define VA_BITS_SV48 48 +#define VA_BITS_SV57 57 + +#define VA_USER_SV39 (UL(1) << (VA_BITS_SV39 - 1)) +#define VA_USER_SV48 (UL(1) << (VA_BITS_SV48 - 1)) +#define VA_USER_SV57 (UL(1) << (VA_BITS_SV57 - 1)) + #define VA_BITS (pgtable_l5_enabled ? \ - 57 : (pgtable_l4_enabled ? 48 : 39)) + VA_BITS_SV57 : (pgtable_l4_enabled ? VA_BITS_SV48 : VA_BITS_SV39)) #else #define VA_BITS 32 #endif +#define DEFAULT_VA_BITS ((VA_BITS >= VA_BITS_SV48) ? VA_BITS_SV48 : VA_BITS) + #define VMEMMAP_SHIFT \ (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT) #define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT) diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 94a0590c6971..468a1f4b9da4 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -12,20 +12,40 @@ #include -/* - * This decides where the kernel will search for a free chunk of vm - * space during mmap's. - */ -#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) - -#define STACK_TOP TASK_SIZE #ifdef CONFIG_64BIT +#define DEFAULT_MAP_WINDOW (UL(1) << (DEFAULT_VA_BITS - 1)) #define STACK_TOP_MAX TASK_SIZE_64 + +#define arch_get_mmap_end(addr, len, flags) \ + ((addr) >= VA_USER_SV57 ? STACK_TOP_MAX : \ + ((((addr) >= VA_USER_SV48)) && (VA_BITS >= VA_BITS_SV48)) ? \ + VA_USER_SV48 : \ + VA_USER_SV39) + +#define arch_get_mmap_base(addr, base) \ + (((addr >= VA_USER_SV57) && (VA_BITS >= VA_BITS_SV57)) ? \ + VA_USER_SV57 - (DEFAULT_MAP_WINDOW - base) : \ + ((((addr) >= VA_USER_SV48)) && (VA_BITS >= VA_BITS_SV48)) ? \ + VA_USER_SV48 - (DEFAULT_MAP_WINDOW - base) : \ + (addr == 0) ? \ + base : \ + VA_USER_SV39 - (DEFAULT_MAP_WINDOW - base)) + #else +#define DEFAULT_MAP_WINDOW TASK_SIZE #define STACK_TOP_MAX TASK_SIZE #endif #define STACK_ALIGN 16 + +#define STACK_TOP DEFAULT_MAP_WINDOW + +/* + * This decides where the kernel will search for a free chunk of vm + * space during mmap's. + */ +#define TASK_UNMAPPED_BASE PAGE_ALIGN(DEFAULT_MAP_WINDOW / 3) + #ifndef __ASSEMBLY__ struct task_struct; From patchwork Wed Jul 5 18:59:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Charlie Jenkins X-Patchwork-Id: 116306 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:9f45:0:b0:3ea:f831:8777 with SMTP id v5csp2081589vqx; Wed, 5 Jul 2023 12:12:42 -0700 (PDT) X-Google-Smtp-Source: APBJJlGDDB5s5THSojnSSbSiZIxZw7tVDreoQDkAUGS6cJvSQYBSA2TZDGLZ1eTuAqLf//j0uZIg X-Received: by 2002:a17:90a:f2d5:b0:262:f06a:13e0 with SMTP id gt21-20020a17090af2d500b00262f06a13e0mr13728095pjb.5.1688584361802; Wed, 05 Jul 2023 12:12:41 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1688584361; cv=none; d=google.com; s=arc-20160816; b=olvhN8/5Zoc871vFkWfvDjkKuc8I/cvyHrs6vwG+eyQTON5oVMs9DjSnsahHRR/dHG Y2QWfm38zLbgUgigbOZ3JzFxHRaKCQXaqE8WIvE8V+2M8bT0WbL1XZDMRrqj/nK+IsJv w82R61BaMp1P/0ZXkWJ0aJEUX4qQ9MkxN2TXOIJ4fp1zmHoMZ6OShV5NSMjOQZI4cdkO MzJpzNDJnfwcAVWDbcW+khOdzR8spFy93KE5LUNbdZgEWkUrGR+eJSLTG9k+oBhjuGY4 bQ6Gt5d9yCXUO2W1HttFilBIfE1ilRZwphlyXcF+mkcIdt6kzQ81XJpFgQ/8V25hQUrw bk5g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=g+onSdyNmgQC+v4LtELg3zbx9wOUlyHN/0HEir9Iam0=; fh=B6InlnakgCOMhE0Jo7qCWVHZRq1xmzaWTN1j+WVFWWQ=; b=lAcMpkzdxiQlDyc3yYvkHhE01L44A3j4AX3rnJjTopc9XIUqNlUvv7sRVJdPOT3Gf9 bQjUAh4c9vKfNPOhY86tb3aLJcWm7pV1h5Keyejx0zE7tRAenP364+ySGXrWp4kuNJ0l S13fm+WX7ThplL6UwGMnWLB33vY5nML/8t6HpeivONvX0+3bALIM8dtVLXCvHQgluvP+ KkfctIE1dVNVcRc2sRNEfSZdVUeCRDv2Vy0bE0NX5GGz+uEzmHiMTTxrU3ihc57Xc6et JZ1JvNd1DwN1shEUdgPgXqa4CIIpqpOHQwwSq5bdYgYjUh0dbEkn7EOy2de5twsyFD3P O6Uw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@rivosinc-com.20221208.gappssmtp.com header.s=20221208 header.b=Y2UVb5+n; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (out1.vger.email. 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Include a simple test that ensures that mmap returns an address less than the hint address while there are still addresses available. Signed-off-by: Charlie Jenkins --- Documentation/riscv/vm-layout.rst | 22 +++++++++ arch/riscv/include/asm/pgtable.h | 8 +-- tools/testing/selftests/riscv/Makefile | 2 +- tools/testing/selftests/riscv/mm/.gitignore | 1 + tools/testing/selftests/riscv/mm/Makefile | 21 ++++++++ .../selftests/riscv/mm/testcases/mmap.c | 49 +++++++++++++++++++ 6 files changed, 99 insertions(+), 4 deletions(-) create mode 100644 tools/testing/selftests/riscv/mm/.gitignore create mode 100644 tools/testing/selftests/riscv/mm/Makefile create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap.c diff --git a/Documentation/riscv/vm-layout.rst b/Documentation/riscv/vm-layout.rst index 5462c84f4723..a610c68c9f3f 100644 --- a/Documentation/riscv/vm-layout.rst +++ b/Documentation/riscv/vm-layout.rst @@ -133,3 +133,25 @@ RISC-V Linux Kernel SV57 ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | modules, BPF ffffffff80000000 | -2 GB | ffffffffffffffff | 2 GB | kernel __________________|____________|__________________|_________|____________________________________________________________ + + +Userspace VAs +-------------------- +To maintain compatibility with software that relies on the VA space +with a maximum of 39-bits, the kernel will, by default, return virtual +return virtual addresses to userspace from a 48-bit range (sv48). This +default behavior is achieved by passing 0 into the hint address parameter +of mmap. + +Software can "opt-in" to receiving VAs from other VA space by providing +a hint address to mmap. A call to mmap is guaranteed to return an address +that will not override the unset left-aligned bits in the hint address, +unless there is no space left in the address space. If there is no space +available in the requested address space, an address in the next smallest +available address space will be returned. + +For example, in order to obtain 48-bit VA space, a hint address greater than +:code:`1 << 38` must be provided. Note that this is 38 due to sv39 userspace +ending at :code:`1 << 38` with the addresses beyond this and up to :code:`1 << 39` +being reserved for the kernel. Similarly, to obtain 57-bit VA space addresses, a +hint address greater than or equal to :code:`1 << 47` must be provided. diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 752e210c7547..5ac973193fab 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -841,14 +841,16 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32. * Note that PGDIR_SIZE must evenly divide TASK_SIZE. * Task size is: - * - 0x9fc00000 (~2.5GB) for RV32. - * - 0x4000000000 ( 256GB) for RV64 using SV39 mmu - * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu + * - 0x9fc00000 (~2.5GB) for RV32. + * - 0x4000000000 ( 256GB) for RV64 using SV39 mmu + * - 0x800000000000 ( 128TB) for RV64 using SV48 mmu + * - 0x100000000000000 ( 64PB) for RV64 using SV57 mmu * * Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V * Instruction Set Manual Volume II: Privileged Architecture" states that * "load and store effective addresses, which are 64bits, must have bits * 63–48 all equal to bit 47, or else a page-fault exception will occur." + * Similarly for SV57, bits 63–57 must be equal to bit 56. */ #ifdef CONFIG_64BIT #define TASK_SIZE_64 (PGDIR_SIZE * PTRS_PER_PGD / 2) diff --git a/tools/testing/selftests/riscv/Makefile b/tools/testing/selftests/riscv/Makefile index 32a72902d045..0fee58f990ae 100644 --- a/tools/testing/selftests/riscv/Makefile +++ b/tools/testing/selftests/riscv/Makefile @@ -5,7 +5,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not) ifneq (,$(filter $(ARCH),riscv)) -RISCV_SUBTARGETS ?= hwprobe +RISCV_SUBTARGETS ?= hwprobe mm else RISCV_SUBTARGETS := endif diff --git a/tools/testing/selftests/riscv/mm/.gitignore b/tools/testing/selftests/riscv/mm/.gitignore new file mode 100644 index 000000000000..022ea0a3f7df --- /dev/null +++ b/tools/testing/selftests/riscv/mm/.gitignore @@ -0,0 +1 @@ +mmap \ No newline at end of file diff --git a/tools/testing/selftests/riscv/mm/Makefile b/tools/testing/selftests/riscv/mm/Makefile new file mode 100644 index 000000000000..d41a0b3d2ca2 --- /dev/null +++ b/tools/testing/selftests/riscv/mm/Makefile @@ -0,0 +1,21 @@ +# SPDX-License-Identifier: GPL-2.0 +# Originally tools/testing/selftests/arm64/signal + +# Additional include paths needed by kselftest.h and local headers +CFLAGS += -D_GNU_SOURCE -std=gnu99 -I. + +SRCS := $(filter-out testcases/testcases.c,$(wildcard testcases/*.c)) +PROGS := $(patsubst %.c,%,$(SRCS)) + +# Generated binaries to be installed by top KSFT script +TEST_GEN_PROGS := $(notdir $(PROGS)) + +# Get Kernel headers installed and use them. + +# Including KSFT lib.mk here will also mangle the TEST_GEN_PROGS list +# to account for any OUTPUT target-dirs optionally provided by +# the toplevel makefile +include ../../lib.mk + +$(TEST_GEN_PROGS): $(PROGS) + cp $(PROGS) $(OUTPUT)/ \ No newline at end of file diff --git a/tools/testing/selftests/riscv/mm/testcases/mmap.c b/tools/testing/selftests/riscv/mm/testcases/mmap.c new file mode 100644 index 000000000000..781576f4c14b --- /dev/null +++ b/tools/testing/selftests/riscv/mm/testcases/mmap.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include "../../kselftest_harness.h" + +TEST(sv57_test) +{ + // Only works on 64 bit + #if __riscv_xlen == 64 + // Place all of the hint addresses on the boundaries of mmap + // sv39, sv48, sv57 + // User addresses end at 1<<38, 1<<47, 1<<56 respectively + void *on_37_bits = (void *) (1UL << 37); + void *on_38_bits = (void *) (1UL << 38); + void *on_46_bits = (void *) (1UL << 46); + void *on_47_bits = (void *) (1UL << 47); + void *on_55_bits = (void *) (1UL << 55); + void *on_56_bits = (void *) (1UL << 56); + + int prot = PROT_READ | PROT_WRITE; + int flags = MAP_PRIVATE | MAP_ANONYMOUS; + + int *no_hint = mmap(NULL, 5*sizeof(int), prot, flags, 0, 0); + int *on_37_addr = mmap(on_37_bits, 5*sizeof(int), prot, flags, 0, 0); + int *on_38_addr = mmap(on_38_bits, 5*sizeof(int), prot, flags, 0, 0); + int *on_46_addr = mmap(on_46_bits, 5*sizeof(int), prot, flags, 0, 0); + int *on_47_addr = mmap(on_47_bits, 5*sizeof(int), prot, flags, 0, 0); + int *on_55_addr = mmap(on_55_bits, 5*sizeof(int), prot, flags, 0, 0); + int *on_56_addr = mmap(on_56_bits, 5*sizeof(int), prot, flags, 0, 0); + + EXPECT_NE(no_hint, MAP_FAILED); + EXPECT_NE(on_37_addr, MAP_FAILED); + EXPECT_NE(on_38_addr, MAP_FAILED); + EXPECT_NE(on_46_addr, MAP_FAILED); + EXPECT_NE(on_47_addr, MAP_FAILED); + EXPECT_NE(on_55_addr, MAP_FAILED); + EXPECT_NE(on_56_addr, MAP_FAILED); + + EXPECT_LT((unsigned long) no_hint, 1UL << 47); + EXPECT_LT((unsigned long) on_37_addr, 1UL << 38); + EXPECT_LT((unsigned long) on_38_addr, 1UL << 38); + EXPECT_LT((unsigned long) on_46_addr, 1UL << 38); + EXPECT_LT((unsigned long) on_47_addr, 1UL << 47); + EXPECT_LT((unsigned long) on_55_addr, 1UL << 47); + EXPECT_LT((unsigned long) on_56_addr, 1UL << 57); + #else + #endif +} + +TEST_HARNESS_MAIN