From nobody Sun Feb 8 18:27:23 2026 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 E3D9AC0015E for ; Thu, 20 Jul 2023 17:40:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231605AbjGTRk2 (ORCPT ); Thu, 20 Jul 2023 13:40:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231873AbjGTRkW (ORCPT ); Thu, 20 Jul 2023 13:40:22 -0400 Received: from mail-ej1-x64a.google.com (mail-ej1-x64a.google.com [IPv6:2a00:1450:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE6AC271E for ; Thu, 20 Jul 2023 10:40:13 -0700 (PDT) Received: by mail-ej1-x64a.google.com with SMTP id a640c23a62f3a-992e6840901so133130166b.0 for ; Thu, 20 Jul 2023 10:40:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1689874812; x=1690479612; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=ZFdlPS8QU525qbseVaI8WzYFYY2eCpYrAzmO7CfAnMA=; b=gJXMrH2tT491ow+xnauMdpysCLCAJ+RDEqD/SLy8C4UJb3ZHOSt+HPScELWiPnd6Hl EgPVzLs9fAJxMtb9Wq/SxTw3WytI13SVmdB8ORp+iTzTCcxDvlsKylsoui07QxQDInAD /9FMahDgy322UqZZ75gamiyd8g0G2vz5W/jVlwICHmroyaH/dHKSYTV4aNFxQC03JJna likRyW3LmN0QMyvv1FGPqtSV36h9M+3NjKDniqhaokMRI7LAP642BRS+yNxhzF59nEa2 P45LzS/pBT/tgHOWdHlIvkWorFdwQgBTOK2XkBkRvE60ydAvvvczDdq0r/nO1GulTWSP Bbbw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689874812; x=1690479612; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ZFdlPS8QU525qbseVaI8WzYFYY2eCpYrAzmO7CfAnMA=; b=QFwtr8IhU4kMi/A/F/LcHSI1E2zvSMTsgdB2+NdGFKc5r4nV5UCJWI333g4td2N3xQ L5K5Ts78ofB0bAr6SrYM1UeTZUSn8AS9CmBz70PrybWPfBDPoxFSQ2b2i3Im5ON8K5YC /xscwAnGly4bJIgcxw/u2pXnjzbEFfXL175VxmbxlnzoKOsNdXY3kRUbAgGSzrPtCn2M hA90igDy5kJY/bMezl3sC2XGq+HR6+L9aFo1z4GzfgKb+2zpeuodUOnMBERP2TLmg7s6 3NMam2vaJmSFxYS1bIUPWtKnq+lCDEFSkZpxYhw65eCVmFtTXLXTnTID9PUX/O21hTQg koiQ== X-Gm-Message-State: ABy/qLYYv+bOF4+a89CFnHJPqMrjYS/i9YTImrvyqzxHbqp2laf9n2Td byOZfgBkOIM0XFEfxIAtFhyKvlsp1M8= X-Google-Smtp-Source: APBJJlElRD+VfI5teixL3w8qtS/2YeCEI0Sjn5/koYwrP6GxqBQLWhchia4hn1WKPns4amyXNoZ983lWI+Q= X-Received: from glider.muc.corp.google.com ([2a00:79e0:9c:201:c495:c29a:e275:1dfb]) (user=glider job=sendgmr) by 2002:a17:907:2ccc:b0:98e:4bf5:8fd6 with SMTP id hg12-20020a1709072ccc00b0098e4bf58fd6mr28414ejc.6.1689874812257; Thu, 20 Jul 2023 10:40:12 -0700 (PDT) Date: Thu, 20 Jul 2023 19:39:55 +0200 In-Reply-To: <20230720173956.3674987-1-glider@google.com> Mime-Version: 1.0 References: <20230720173956.3674987-1-glider@google.com> X-Mailer: git-send-email 2.41.0.487.g6d72f3e995-goog Message-ID: <20230720173956.3674987-5-glider@google.com> Subject: [PATCH v4 4/5] arm64: mte: add a test for MTE tags compression From: Alexander Potapenko To: glider@google.com, catalin.marinas@arm.com, will@kernel.org, pcc@google.com, andreyknvl@gmail.com, andriy.shevchenko@linux.intel.com, linux@rasmusvillemoes.dk, yury.norov@gmail.com Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, eugenis@google.com, syednwaris@gmail.com, william.gray@linaro.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Ensure that tag sequences containing alternating values are compressed to buffers of expected size and correctly decompressed afterwards. Signed-off-by: Alexander Potapenko --- v4: - addressed comments by Andy Shevchenko: - expanded MTE to "Memory Tagging Extension" in Kconfig - changed signed variables to unsigned where applicable - added missing header dependencies - addressed comments by Yury Norov: - moved test-only declarations from mtecomp.h into this test - switched to the new "mte"-prefixed function names, dropped the mentions of "EA0" - added test_tag_to_ranges_n() v3: - addressed comments by Andy Shevchenko in another patch: - switched from u64 to unsigned long - added MODULE_IMPORT_NS(MTECOMP) - fixed includes order --- arch/arm64/Kconfig | 10 ++ arch/arm64/mm/Makefile | 1 + arch/arm64/mm/test_mtecomp.c | 217 +++++++++++++++++++++++++++++++++++ 3 files changed, 228 insertions(+) create mode 100644 arch/arm64/mm/test_mtecomp.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 3ac6e302b1509..2432475003054 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2102,6 +2102,16 @@ config ARM64_MTE_COMP =20 128-byte tag buffers corresponding to 4K pages can be compressed to sav= e heap memory. =20 +config ARM64_MTE_COMP_KUNIT_TEST + tristate "Test tag compression for ARM64 Memory Tagging Extension" if !KU= NIT_ALL_TESTS + default KUNIT_ALL_TESTS + depends on KUNIT && ARM64_MTE_COMP + help + Test MTE compression algorithm enabled by CONFIG_ARM64_MTE_COMP. + + Ensure that tag sequences containing alternating values are compressed + to buffers of expected size and correctly decompressed afterwards. + config ARM64_SVE bool "ARM Scalable Vector Extension support" default y diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index 46778f6dd83c2..170dc62b010b9 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_TRANS_TABLE) +=3D trans_pgd-asm.o obj-$(CONFIG_DEBUG_VIRTUAL) +=3D physaddr.o obj-$(CONFIG_ARM64_MTE) +=3D mteswap.o obj-$(CONFIG_ARM64_MTE_COMP) +=3D mtecomp.o +obj-$(CONFIG_ARM64_MTE_COMP_KUNIT_TEST) +=3D test_mtecomp.o KASAN_SANITIZE_physaddr.o +=3D n =20 obj-$(CONFIG_KASAN) +=3D kasan_init.o diff --git a/arch/arm64/mm/test_mtecomp.c b/arch/arm64/mm/test_mtecomp.c new file mode 100644 index 0000000000000..185eb6cb73650 --- /dev/null +++ b/arch/arm64/mm/test_mtecomp.c @@ -0,0 +1,217 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test cases for MTE tags compression algorithm. + */ + +#include +#include +#include +#include +#include +#include + +#include + +/* Functions exported from mtecomp.c for this test. */ +void mte_tags_to_ranges(u8 *tags, u8 *out_tags, unsigned short *out_sizes, + size_t *out_len); +void mte_ranges_to_tags(u8 *r_tags, unsigned short *r_sizes, size_t r_len, + u8 *tags); + +/* + * Test that mte_tags_to_ranges() produces a single range for a zero-fille= d tag + * buffer. + */ +static void test_tags_to_ranges_zero(struct kunit *test) +{ + u8 tags[128], dtags[128]; + unsigned short r_sizes[256]; + size_t r_len =3D 256; + u8 r_tags[256]; + + memset(tags, 0, 128); + mte_tags_to_ranges(tags, r_tags, r_sizes, &r_len); + KUNIT_EXPECT_EQ(test, r_len, 1); + KUNIT_EXPECT_EQ(test, r_tags[0], 0); + KUNIT_EXPECT_EQ(test, r_sizes[0], 256); + mte_ranges_to_tags(r_tags, r_sizes, r_len, dtags); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); +} + +/* + * Test that a small number of different tags is correctly transformed into + * ranges. + */ +static void test_tags_to_ranges_simple(struct kunit *test) +{ + u8 tags[128], dtags[128]; + const u8 ex_tags[] =3D { 0xa, 0x0, 0xa, 0xb, 0x0 }; + const unsigned short ex_sizes[] =3D { 1, 2, 2, 1, 250 }; + unsigned short r_sizes[256]; + size_t r_len =3D 256; + u8 r_tags[256]; + + memset(tags, 0, 128); + tags[0] =3D 0xa0; + tags[1] =3D 0x0a; + tags[2] =3D 0xab; + mte_tags_to_ranges(tags, r_tags, r_sizes, &r_len); + KUNIT_EXPECT_EQ(test, r_len, 5); + KUNIT_EXPECT_EQ(test, memcmp(r_tags, ex_tags, sizeof(ex_tags)), 0); + KUNIT_EXPECT_EQ(test, memcmp(r_sizes, ex_sizes, sizeof(ex_sizes)), 0); + mte_ranges_to_tags(r_tags, r_sizes, r_len, dtags); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); +} + +/* Test that repeated 0xa0 byte produces 256 ranges of length 1. */ +static void test_tags_to_ranges_repeated(struct kunit *test) +{ + u8 tags[128], dtags[128]; + unsigned short r_sizes[256]; + size_t r_len =3D 256; + u8 r_tags[256]; + + memset(tags, 0xa0, 128); + mte_tags_to_ranges(tags, r_tags, r_sizes, &r_len); + KUNIT_EXPECT_EQ(test, r_len, 256); + mte_ranges_to_tags(r_tags, r_sizes, r_len, dtags); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); +} + +/* Generate a buffer that will contain @nranges of tag ranges. */ +static void gen_tag_range_helper(u8 *tags, int nranges) +{ + unsigned int i; + + memset(tags, 0, 128); + if (nranges > 1) { + nranges--; + for (i =3D 0; i < nranges / 2; i++) + tags[i] =3D 0xab; + if (nranges % 2) + tags[nranges / 2] =3D 0xa0; + } +} + +/* + * Test that mte_tags_to_ranges()/mte_ranges_to_tags() work for various + * r_len values. + */ +static void test_tag_to_ranges_n(struct kunit *test) +{ + unsigned short r_sizes[256]; + u8 tags[128], dtags[128]; + unsigned int i, j, sum; + size_t r_len =3D 256; + u8 r_tags[256]; + + for (i =3D 1; i <=3D 256; i++) { + gen_tag_range_helper(tags, i); + mte_tags_to_ranges(tags, r_tags, r_sizes, &r_len); + sum =3D 0; + for (j =3D 0; j < r_len; j++) + sum +=3D r_sizes[j]; + KUNIT_EXPECT_EQ(test, sum, 256); + mte_ranges_to_tags(r_tags, r_sizes, r_len, dtags); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); + } +} + +/* Test that a zero-filled array is compressed into inline storage. */ +static void test_compress_zero(struct kunit *test) +{ + u8 tags[128], dtags[128]; + unsigned long handle; + + memset(tags, 0, 128); + handle =3D mte_compress(tags); + KUNIT_EXPECT_EQ(test, handle & BIT_ULL(63), 0); + /* Tags are stored inline. */ + KUNIT_EXPECT_EQ(test, mte_storage_size(handle), 8); + KUNIT_EXPECT_TRUE(test, mte_decompress(handle, dtags)); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); +} + +/* + * Test that a very small number of tag ranges ends up compressed into 8 b= ytes. + */ +static void test_compress_simple(struct kunit *test) +{ + u8 tags[128], dtags[128]; + unsigned long handle; + + memset(tags, 0, 128); + tags[0] =3D 0xa0; + tags[1] =3D 0x0a; + tags[2] =3D 0xab; + + handle =3D mte_compress(tags); + KUNIT_EXPECT_EQ(test, handle & BIT_ULL(63), 0); + /* Tags are stored inline. */ + KUNIT_EXPECT_EQ(test, mte_storage_size(handle), 8); + KUNIT_EXPECT_TRUE(test, mte_decompress(handle, dtags)); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); +} + +/* + * Test that a buffer containing @nranges ranges compresses into @exp_size + * bytes and decompresses into the original tag sequence. + */ +static void compress_range_helper(struct kunit *test, int nranges, + size_t exp_size) +{ + u8 tags[128], dtags[128]; + unsigned long handle; + + gen_tag_range_helper(tags, nranges); + handle =3D mte_compress(tags); + KUNIT_EXPECT_EQ(test, handle & BIT_ULL(63), 0); + KUNIT_EXPECT_EQ(test, mte_storage_size(handle), exp_size); + KUNIT_EXPECT_TRUE(test, mte_decompress(handle, dtags)); + KUNIT_EXPECT_EQ(test, memcmp(tags, dtags, 128), 0); +} + +/* + * Test that every number of tag ranges is correctly compressed and + * decompressed. + */ +static void test_compress_ranges(struct kunit *test) +{ + size_t exp_size; + unsigned int i; + + for (i =3D 1; i <=3D 256; i++) { + if (i < 7) + exp_size =3D 8; + else if (i < 12) + exp_size =3D 16; + else if (i < 24) + exp_size =3D 32; + else if (i < 47) + exp_size =3D 64; + else + exp_size =3D 128; + compress_range_helper(test, i, exp_size); + } +} + +static struct kunit_case mtecomp_test_cases[] =3D { + KUNIT_CASE(test_tags_to_ranges_zero), + KUNIT_CASE(test_tags_to_ranges_simple), + KUNIT_CASE(test_tags_to_ranges_repeated), + KUNIT_CASE(test_tag_to_ranges_n), + KUNIT_CASE(test_compress_zero), + KUNIT_CASE(test_compress_simple), + KUNIT_CASE(test_compress_ranges), + {} +}; + +static struct kunit_suite mtecomp_test_suite =3D { + .name =3D "mtecomp", + .test_cases =3D mtecomp_test_cases, +}; +kunit_test_suites(&mtecomp_test_suite); + +MODULE_IMPORT_NS(MTECOMP); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alexander Potapenko "); --=20 2.41.0.487.g6d72f3e995-goog