From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A0C9E315785; Sat, 14 Mar 2026 17:51:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773510705; cv=none; b=jIatOSmzzHCA+qdezkwpWbLcozrz9vEZmkqcHq6qbVYyyP9szIy88GZXEEH2Ytn2nVImp+3pduMRdf3J2pgxMfGjz1cwff+axtO07vVmnFI3XiQn6aFjxRZyej1yAI6e/LLeD82wPKpBLM3I/K32O5xi5k/dY2s0iTg1CrHEwm0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773510705; c=relaxed/simple; bh=ky0TodqFmtCk9igM06yYCVcwJU5iu8azLX4ItOahUsU=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=OQqleuJNSwDqialccZDL9VPAQH2Y6ZmwaOahjtoPMRnqnVY0ls4raRmaWtbe0ofOL6aEltFX61tLPAzk3YF6A4riCVl2rR7btvu3hZ5KIreV7xIkyJoPrulPTrR9g9aPwfT85teU413H9/IGftPj3sruayWSLDGfNovd11h3EbA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 79262152B; Sat, 14 Mar 2026 10:51:31 -0700 (PDT) Received: from e129823.cambridge.arm.com (e129823.arm.com [10.1.197.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 21C013F73B; Sat, 14 Mar 2026 10:51:35 -0700 (PDT) From: Yeoreum Yun To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: catalin.marinas@arm.com, will@kernel.org, maz@kernel.org, oupton@kernel.org, miko.lenczewski@arm.com, kevin.brodsky@arm.com, broonie@kernel.org, ardb@kernel.org, suzuki.poulose@arm.com, lpieralisi@kernel.org, joey.gouly@arm.com, yuzenghui@huawei.com, yeoreum.yun@arm.com Subject: [PATCH v17 0/8] support FEAT_LSUI Date: Sat, 14 Mar 2026 17:51:25 +0000 Message-Id: <20260314175133.1084528-1-yeoreum.yun@arm.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Since Armv9.6, FEAT_LSUI supplies the load/store instructions for previleged level to access to access user memory without clearing PSTATE.PAN bit. This patchset support FEAT_LSUI and applies it mainly in futex atomic operation and others. This patch based on v7.0-rc3 Patch History ============== from v16 to v17 - remove loops in __lsui_cmpxchg32(). - modify some comments and move them to commit message. - https://lore.kernel.org/all/20260312175243.1593864-1-yeoreum.yun@arm.com/ from v15 to v16: - remove positional operand in futex asm. - rebased to v7.0-rc3 - https://lore.kernel.org/all/20260227151705.1275328-1-yeoreum.yun@arm.com/ from v14 to v15: - replace caslt to cast - cleanup the patch - https://lore.kernel.org/all/20260225182708.3225211-1-yeoreum.yun@arm.com/ from v13 to v14: - add LSUI config check in cpucap_is_possible() - fix build failure with clang-19 - https://lore.kernel.org/all/20260223174802.458411-1-yeoreum.yun@arm.com/ from v12 to v13: - rebase to v7.0-rc1 - apply CASLT for swapping guest descriptor - remove has_lsui() for checking cpu feature. - simplify __lsui_cmpxchg32() according to @Catalin's suggestion. - use uaccess_ttbr0_enable()/disable() for LSUI instructions. - https://lore.kernel.org/all/aYWuqTqM5MvudI5V@e129823.arm.com/ from v11 to v12: - rebase to v6.19-rc6 - add CONFIG_ARM64_LSUI - enable LSUI when !CPU_BIG_ENDIAN and PAN presents. - drop the swp emulation with LSUI insns instead, disable it when LSUI presents. - some of small fixes (useless prefix and suffix and etc). - https://lore.kernel.org/all/20251214112248.901769-1-yeoreum.yun@arm.com/ from v10 to v11: - rebase to v6.19-rc1 - use cast instruction to emulate deprecated swpb instruction - https://lore.kernel.org/all/20251103163224.818353-1-yeoreum.yun@arm.com/ from v9 to v10: - apply FEAT_LSUI to user_swpX emulation. - add test coverage for LSUI bit in ID_AA64ISAR3_EL1 - rebase to v6.18-rc4 - https://lore.kernel.org/all/20250922102244.2068414-1-yeoreum.yun@arm.com/ from v8 to v9: - refotoring __lsui_cmpxchg64() - rebase to v6.17-rc7 - https://lore.kernel.org/all/20250917110838.917281-1-yeoreum.yun@arm.com/ from v7 to v8: - implements futex_atomic_eor() and futex_atomic_cmpxchg() with casalt with C helper. - Drop the small optimisation on ll/sc futex_atomic_set operation. - modify some commit message. - https://lore.kernel.org/all/20250816151929.197589-1-yeoreum.yun@arm.com/ from v6 to v7: - wrap FEAT_LSUI with CONFIG_AS_HAS_LSUI in cpufeature - remove unnecessary addition of indentation. - remove unnecessary mte_tco_enable()/disable() on LSUI operation. - https://lore.kernel.org/all/20250811163635.1562145-1-yeoreum.yun@arm.com/ from v5 to v6: - rebase to v6.17-rc1 - https://lore.kernel.org/all/20250722121956.1509403-1-yeoreum.yun@arm.com/ from v4 to v5: - remove futex_ll_sc.h futext_lsui and lsui.h and move them to futex.h - reorganize the patches. - https://lore.kernel.org/all/20250721083618.2743569-1-yeoreum.yun@arm.com/ from v3 to v4: - rebase to v6.16-rc7 - modify some patch's title. - https://lore.kernel.org/all/20250617183635.1266015-1-yeoreum.yun@arm.com/ from v2 to v3: - expose FEAT_LSUI to guest - add help section for LSUI Kconfig - https://lore.kernel.org/all/20250611151154.46362-1-yeoreum.yun@arm.com/ from v1 to v2: - remove empty v9.6 menu entry - locate HAS_LSUI in cpucaps in order - https://lore.kernel.org/all/20250611104916.10636-1-yeoreum.yun@arm.com/ Yeoreum Yun (8): arm64: cpufeature: add FEAT_LSUI KVM: arm64: expose FEAT_LSUI to guest KVM: arm64: kselftest: set_id_regs: add test for FEAT_LSUI arm64: futex: refactor futex atomic operation arm64: futex: support futex with FEAT_LSUI arm64: armv8_deprecated: disable swp emulation when FEAT_LSUI present KVM: arm64: use CAST instruction for swapping guest descriptor arm64: Kconfig: add support for LSUI arch/arm64/Kconfig | 20 ++ arch/arm64/include/asm/cpucaps.h | 2 + arch/arm64/include/asm/futex.h | 307 ++++++++++++++---- arch/arm64/include/asm/lsui.h | 27 ++ arch/arm64/kernel/armv8_deprecated.c | 16 + arch/arm64/kernel/cpufeature.c | 10 + arch/arm64/kvm/at.c | 34 +- arch/arm64/kvm/sys_regs.c | 3 +- arch/arm64/tools/cpucaps | 1 + .../testing/selftests/kvm/arm64/set_id_regs.c | 1 + 10 files changed, 361 insertions(+), 60 deletions(-) create mode 100644 arch/arm64/include/asm/lsui.h -- LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}