From patchwork Wed Aug 9 01:51:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Charlie Jenkins X-Patchwork-Id: 712118 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91FA8C41513 for ; Wed, 9 Aug 2023 01:53:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231297AbjHIBxP (ORCPT ); Tue, 8 Aug 2023 21:53:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231185AbjHIBxL (ORCPT ); Tue, 8 Aug 2023 21:53:11 -0400 Received: from mail-pl1-x62b.google.com (mail-pl1-x62b.google.com [IPv6:2607:f8b0:4864:20::62b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2281F3 for ; Tue, 8 Aug 2023 18:53:09 -0700 (PDT) Received: by mail-pl1-x62b.google.com with SMTP id d9443c01a7336-1bc7b25c699so13976265ad.1 for ; Tue, 08 Aug 2023 18:53:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20221208.gappssmtp.com; s=20221208; t=1691545989; x=1692150789; 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=IqoPeA6wKcuCb1RtSAVao8nNOFMZCDDFQoFYxZEN+6o=; b=jfbSHkA7Pa9V10urCv21V3jIQY0QYOUZGE1Ipo41h89RqVS7Dlo1ZQf/9rDavN4Lol /9kpDm9g8K7UrGHoO0oBeNtrqiogHaSkuyH2qTnD2kAuNTN9/Wq9ZqnMrYKfFcotBYnA bgGT1QaHtdTyUqRU50oFnAWOmS2swDrenCSlf2rghBXKg1HjhoiTsQ3lFtu3U6CSvBfL HH355Zp66vKcPv+H4ev3D1zj5+VOQTUhnccIF8ox38aKRiflUWNizWFAg6sqVrV/g6Jy Nxe3PjFb30KRffIufTnykwJsYVZg6qefwS+oa+S+2RWoz4C7TVc4M2O5uPwxKqUOmIdU g43A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691545989; x=1692150789; 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=IqoPeA6wKcuCb1RtSAVao8nNOFMZCDDFQoFYxZEN+6o=; b=F8eqjFeWg3iv0qn8KSryeLSCvNtevBNfP1VFW1kOu+lycJ/PBfpeeS6YEsl9W1PDJa 3FGnReesg3BC66R0PqdftxejOp0wVVpDHewLb2QPxsW+10MskznNF5kg37zMOvWqHZuu qsFCatCPGMEtOUc3+DaByGS8lWaa2D5LoOHs988eI0yFVA1SP2CZkVOr7BoEiiQKjM72 DPvCFkdNUrtNIwKtiDkPbopDEJNKOhPIpibu4SNLK9yoOBIA62TiCGN76WbRNwSEc5g6 5WhJxkZWf8rM85JtD0GjyyJ1FS11LUbMOcqYKvYpW/dlw+dakfXoAzMLJoztw8+XYp3L eOUw== X-Gm-Message-State: AOJu0Yx97lfo6c3CCrnagFrucs9fXDJu/9DHDRaD7jcY5Gs6Yxp4uTah j18ZyrSjPpRgDm7j4MID6dNx0g== X-Google-Smtp-Source: AGHT+IHFQGEUvoYO9sxgVWzTl8vUEdV44C3X/h5cs/VEo+Kv4prar8zZst792RMZqIZyj/nYul07Xg== X-Received: by 2002:a17:902:ec81:b0:1b6:af1a:7dd3 with SMTP id x1-20020a170902ec8100b001b6af1a7dd3mr1496825plg.23.1691545989416; Tue, 08 Aug 2023 18:53:09 -0700 (PDT) Received: from charlie.ba.rivosinc.com ([66.220.2.162]) by smtp.gmail.com with ESMTPSA id bj7-20020a170902850700b001b87bedcc6fsm9657591plb.93.2023.08.08.18.53.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 08 Aug 2023 18:53:08 -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, rdunlap@infradead.org, alexghiti@rivosinc.com Subject: [PATCH v9 2/4] RISC-V: mm: Add tests for RISC-V mm Date: Tue, 8 Aug 2023 18:51:08 -0700 Message-Id: <20230809015110.3290774-3-charlie@rivosinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230809015110.3290774-1-charlie@rivosinc.com> References: <20230809015110.3290774-1-charlie@rivosinc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Add tests that enforce mmap hint address behavior. mmap should default to sv48. mmap will provide an address at the highest address space that can fit into the hint address, unless the hint address is less than sv39 and not 0, then it will return a sv39 address. These tests are split into two files: mmap_default.c and mmap_bottomup.c because a new process must be exec'd in order to change the mmap layout. The run_mmap.sh script sets the stack to be unlimited for the mmap_bottomup.c test which triggers a bottomup layout. Signed-off-by: Charlie Jenkins --- tools/testing/selftests/riscv/Makefile | 2 +- tools/testing/selftests/riscv/mm/.gitignore | 2 + tools/testing/selftests/riscv/mm/Makefile | 15 +++++ .../riscv/mm/testcases/mmap_bottomup.c | 35 ++++++++++ .../riscv/mm/testcases/mmap_default.c | 35 ++++++++++ .../selftests/riscv/mm/testcases/mmap_test.h | 64 +++++++++++++++++++ .../selftests/riscv/mm/testcases/run_mmap.sh | 12 ++++ 7 files changed, 164 insertions(+), 1 deletion(-) 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_bottomup.c create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap_default.c create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap_test.h create mode 100755 tools/testing/selftests/riscv/mm/testcases/run_mmap.sh diff --git a/tools/testing/selftests/riscv/Makefile b/tools/testing/selftests/riscv/Makefile index f4b3d5c9af5b..4a9ff515a3a0 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 $(ARCH),riscv)) -RISCV_SUBTARGETS ?= hwprobe vector +RISCV_SUBTARGETS ?= hwprobe vector mm else RISCV_SUBTARGETS := endif diff --git a/tools/testing/selftests/riscv/mm/.gitignore b/tools/testing/selftests/riscv/mm/.gitignore new file mode 100644 index 000000000000..5c2c57cb950c --- /dev/null +++ b/tools/testing/selftests/riscv/mm/.gitignore @@ -0,0 +1,2 @@ +mmap_bottomup +mmap_default diff --git a/tools/testing/selftests/riscv/mm/Makefile b/tools/testing/selftests/riscv/mm/Makefile new file mode 100644 index 000000000000..11e0f0568923 --- /dev/null +++ b/tools/testing/selftests/riscv/mm/Makefile @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2021 ARM Limited +# Originally tools/testing/arm64/abi/Makefile + +# Additional include paths needed by kselftest.h and local headers +CFLAGS += -D_GNU_SOURCE -std=gnu99 -I. + +TEST_GEN_FILES := testcases/mmap_default testcases/mmap_bottomup + +TEST_PROGS := testcases/run_mmap.sh + +include ../../lib.mk + +$(OUTPUT)/mm: testcases/mmap_default.c testcases/mmap_bottomup.c testcases/mmap_tests.h + $(CC) -o$@ $(CFLAGS) $(LDFLAGS) $^ diff --git a/tools/testing/selftests/riscv/mm/testcases/mmap_bottomup.c b/tools/testing/selftests/riscv/mm/testcases/mmap_bottomup.c new file mode 100644 index 000000000000..b29379f7e478 --- /dev/null +++ b/tools/testing/selftests/riscv/mm/testcases/mmap_bottomup.c @@ -0,0 +1,35 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include + +#include "../../kselftest_harness.h" + +TEST(infinite_rlimit) +{ +// Only works on 64 bit +#if __riscv_xlen == 64 + struct addresses mmap_addresses; + + EXPECT_EQ(BOTTOM_UP, memory_layout()); + + do_mmaps(&mmap_addresses); + + EXPECT_NE(MAP_FAILED, mmap_addresses.no_hint); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_37_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_38_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_46_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_47_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_55_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_56_addr); + + EXPECT_GT(1UL << 47, (unsigned long)mmap_addresses.no_hint); + EXPECT_GT(1UL << 38, (unsigned long)mmap_addresses.on_37_addr); + EXPECT_GT(1UL << 38, (unsigned long)mmap_addresses.on_38_addr); + EXPECT_GT(1UL << 38, (unsigned long)mmap_addresses.on_46_addr); + EXPECT_GT(1UL << 47, (unsigned long)mmap_addresses.on_47_addr); + EXPECT_GT(1UL << 47, (unsigned long)mmap_addresses.on_55_addr); + EXPECT_GT(1UL << 56, (unsigned long)mmap_addresses.on_56_addr); +#endif +} + +TEST_HARNESS_MAIN diff --git a/tools/testing/selftests/riscv/mm/testcases/mmap_default.c b/tools/testing/selftests/riscv/mm/testcases/mmap_default.c new file mode 100644 index 000000000000..d1accb91b726 --- /dev/null +++ b/tools/testing/selftests/riscv/mm/testcases/mmap_default.c @@ -0,0 +1,35 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include + +#include "../../kselftest_harness.h" + +TEST(default_rlimit) +{ +// Only works on 64 bit +#if __riscv_xlen == 64 + struct addresses mmap_addresses; + + EXPECT_EQ(TOP_DOWN, memory_layout()); + + do_mmaps(&mmap_addresses); + + EXPECT_NE(MAP_FAILED, mmap_addresses.no_hint); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_37_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_38_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_46_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_47_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_55_addr); + EXPECT_NE(MAP_FAILED, mmap_addresses.on_56_addr); + + EXPECT_GT(1UL << 47, (unsigned long)mmap_addresses.no_hint); + EXPECT_GT(1UL << 38, (unsigned long)mmap_addresses.on_37_addr); + EXPECT_GT(1UL << 38, (unsigned long)mmap_addresses.on_38_addr); + EXPECT_GT(1UL << 38, (unsigned long)mmap_addresses.on_46_addr); + EXPECT_GT(1UL << 47, (unsigned long)mmap_addresses.on_47_addr); + EXPECT_GT(1UL << 47, (unsigned long)mmap_addresses.on_55_addr); + EXPECT_GT(1UL << 56, (unsigned long)mmap_addresses.on_56_addr); +#endif +} + +TEST_HARNESS_MAIN diff --git a/tools/testing/selftests/riscv/mm/testcases/mmap_test.h b/tools/testing/selftests/riscv/mm/testcases/mmap_test.h new file mode 100644 index 000000000000..9b8434f62f57 --- /dev/null +++ b/tools/testing/selftests/riscv/mm/testcases/mmap_test.h @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _TESTCASES_MMAP_TEST_H +#define _TESTCASES_MMAP_TEST_H +#include +#include +#include + +#define TOP_DOWN 0 +#define BOTTOM_UP 1 + +struct addresses { + int *no_hint; + int *on_37_addr; + int *on_38_addr; + int *on_46_addr; + int *on_47_addr; + int *on_55_addr; + int *on_56_addr; +}; + +static inline void do_mmaps(struct addresses *mmap_addresses) +{ + /* + * 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; + + mmap_addresses->no_hint = + mmap(NULL, 5 * sizeof(int), prot, flags, 0, 0); + mmap_addresses->on_37_addr = + mmap(on_37_bits, 5 * sizeof(int), prot, flags, 0, 0); + mmap_addresses->on_38_addr = + mmap(on_38_bits, 5 * sizeof(int), prot, flags, 0, 0); + mmap_addresses->on_46_addr = + mmap(on_46_bits, 5 * sizeof(int), prot, flags, 0, 0); + mmap_addresses->on_47_addr = + mmap(on_47_bits, 5 * sizeof(int), prot, flags, 0, 0); + mmap_addresses->on_55_addr = + mmap(on_55_bits, 5 * sizeof(int), prot, flags, 0, 0); + mmap_addresses->on_56_addr = + mmap(on_56_bits, 5 * sizeof(int), prot, flags, 0, 0); +} + +static inline int memory_layout(void) +{ + int prot = PROT_READ | PROT_WRITE; + int flags = MAP_PRIVATE | MAP_ANONYMOUS; + + void *value1 = mmap(NULL, sizeof(int), prot, flags, 0, 0); + void *value2 = mmap(NULL, sizeof(int), prot, flags, 0, 0); + + return value2 > value1; +} +#endif /* _TESTCASES_MMAP_TEST_H */ diff --git a/tools/testing/selftests/riscv/mm/testcases/run_mmap.sh b/tools/testing/selftests/riscv/mm/testcases/run_mmap.sh new file mode 100755 index 000000000000..ca5ad7c48bad --- /dev/null +++ b/tools/testing/selftests/riscv/mm/testcases/run_mmap.sh @@ -0,0 +1,12 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +original_stack_limit=$(ulimit -s) + +./mmap_default + +# Force mmap_bottomup to be ran with bottomup memory due to +# the unlimited stack +ulimit -s unlimited +./mmap_bottomup +ulimit -s $original_stack_limit From patchwork Wed Aug 9 01:51:10 2023 Content-Type: text/plain; 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Signed-off-by: Charlie Jenkins Reviewed-by: Alexandre Ghiti --- Documentation/riscv/vm-layout.rst | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/Documentation/riscv/vm-layout.rst b/Documentation/riscv/vm-layout.rst index 5462c84f4723..69ff6da1dbf8 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 48 bits the kernel will, by default, 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. On CPUs with an address space +smaller than sv48, the CPU maximum supported address space will be the default. + +Software can "opt-in" to receiving VAs from another VA space by providing +a hint address to mmap. A hint address passed to mmap will cause the largest +address space that fits entirely into the hint to be used, 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 << 47` must be provided. Note that this is 47 due to sv48 userspace +ending at :code:`1 << 47` and the addresses beyond this are reserved for the +kernel. Similarly, to obtain 57-bit VA space addresses, a hint address greater +than or equal to :code:`1 << 56` must be provided.