From patchwork Fri Jan 6 08:55:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13091144 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 B0CAEC5479D for ; Fri, 6 Jan 2023 09:20:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232153AbjAFJUf (ORCPT ); Fri, 6 Jan 2023 04:20:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232849AbjAFJUP (ORCPT ); Fri, 6 Jan 2023 04:20:15 -0500 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3494B6B5B4; Fri, 6 Jan 2023 01:20:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1672996813; x=1704532813; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=bH60lttMRq+HLemkhaHEGZFswOR2yI2RyBlMJvmUNTA=; b=OCzjHHI5XHMwR/uer+oCEMRwnC7amwfV/V6BXcUVkteKjVDVfQbIcaaB J25q0NHfReTXUNHqKMkvbpDwU9KdpJFxbRx+sjbm5dpu5XQO3+0xGyjEI l4CMt6Cv91eFhZQYejKwDm5heE9JLanYwE4iqkTIXvhc2/9iPy98h44Dd Yj7jCWI/CnZ9T6mkOzqJjLyCHG7QVvUwZ66fic37LXqYdsXLQoeIbTlJL Vhynh6GOE2iR+WNAp3anKfJJhIZB/u50heh2eyzoKgVe2OcAwupdZWSpY 5y5Q9Ta16EP6b2ST8LgJr8mr+Lu6uZgqcLLShKV+q7Z+XLQcndnNo/eCQ Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10581"; a="322511361" X-IronPort-AV: E=Sophos;i="5.96,304,1665471600"; d="scan'208";a="322511361" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jan 2023 01:20:12 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10581"; a="719139328" X-IronPort-AV: E=Sophos;i="5.96,304,1665471600"; d="scan'208";a="719139328" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga008.fm.intel.com with ESMTP; 06 Jan 2023 01:20:10 -0800 From: Xin Li To: linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, peterz@infradead.org, andrew.cooper3@citrix.com, seanjc@google.com, pbonzini@redhat.com, ravi.v.shankar@intel.com Subject: [RFC PATCH v2 00/32] x86: enable FRED for x86-64 Date: Fri, 6 Jan 2023 00:55:45 -0800 Message-Id: <20230106085617.17248-1-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch set enables FRED for x86-64, and it's based on the previous LKGS patch set. The Intel flexible return and event delivery (FRED) architecture defines simple new transitions that change privilege level (ring transitions). The FRED architecture was designed with the following goals: 1) Improve overall performance and response time by replacing event delivery through the interrupt descriptor table (IDT event delivery) and event return by the IRET instruction with lower latency transitions. 2) Improve software robustness by ensuring that event delivery establishes the full supervisor context and that event return establishes the full user context. The new transitions defined by the FRED architecture are FRED event delivery and, for returning from events, two FRED return instructions. FRED event delivery can effect a transition from ring 3 to ring 0, but it is used also to deliver events incident to ring 0. One FRED instruction (ERETU) effects a return from ring 0 to ring 3, while the other (ERETS) returns while remaining in ring 0. In addition to these transitions, the FRED architecture defines a new instruction (LKGS) for managing the state of the GS segment register. The LKGS instruction can be used by 64-bit operating systems that do not use the new FRED transitions. The Intel FRED architecture spec can be downloaded from: https://cdrdv2.intel.com/v1/dl/getContent/678938 As of now there is no publicly avaiable CPU supporting FRED, thus the Intel SimicsĀ® Simulator is used as software development and testing vehicle. And it can be downloaded from: https://www.intel.com/content/www/us/en/developer/articles/tool/simics-simulator.html To enable FRED, Simics package 8112 QSP-CPU needs to be installed with CPU model configured as: $cpu_comp_class = "x86-experimental-fred" Longer term, we should refactor common code shared by FRED and IDT into common shared files, and contain IDT code using a new config CONFIG_X86_IDT. TODO: call exc_raise_irq() to reinject IRQ in KVM VMX. H. Peter Anvin (Intel) (24): x86/traps: let common_interrupt() handle IRQ_MOVE_CLEANUP_VECTOR x86/traps: add a system interrupt table for system interrupt dispatch x86/traps: add external_interrupt() to dispatch external interrupts x86/cpufeature: add the cpu feature bit for FRED x86/opcode: add ERETU, ERETS instructions to x86-opcode-map x86/objtool: teach objtool about ERETU and ERETS x86/cpu: add X86_CR4_FRED macro x86/fred: add Kconfig option for FRED (CONFIG_X86_FRED) x86/fred: if CONFIG_X86_FRED is disabled, disable FRED support x86/cpu: add MSR numbers for FRED configuration x86/fred: header file with FRED definitions x86/fred: make unions for the cs and ss fields in struct pt_regs x86/fred: reserve space for the FRED stack frame x86/fred: add a page fault entry stub for FRED x86/fred: add a debug fault entry stub for FRED x86/fred: add a NMI entry stub for FRED x86/fred: FRED entry/exit and dispatch code x86/fred: FRED initialization code x86/fred: update MSR_IA32_FRED_RSP0 during task switch x86/fred: let ret_from_fork() jmp to fred_exit_user when FRED is enabled x86/fred: disallow the swapgs instruction when FRED is enabled x86/fred: no ESPFIX needed when FRED is enabled x86/fred: allow single-step trap and NMI when starting a new thread x86/fred: allow FRED systems to use interrupt vectors 0x10-0x1f Xin Li (8): x86/traps: add install_system_interrupt_handler() x86/traps: add exc_raise_irq() for VMX IRQ reinjection x86/fred: header file for event types x86/fred: add a machine check entry stub for FRED x86/fred: fixup fault on ERETU by jumping to fred_entrypoint_user x86/ia32: do not modify the DPL bits for a null selector x86/fred: allow dynamic stack frame size x86/fred: disable FRED by default in its early stage .../admin-guide/kernel-parameters.txt | 4 + arch/x86/Kconfig | 9 + arch/x86/entry/Makefile | 5 +- arch/x86/entry/entry_32.S | 2 +- arch/x86/entry/entry_64.S | 5 + arch/x86/entry/entry_64_fred.S | 59 +++++ arch/x86/entry/entry_fred.c | 233 ++++++++++++++++++ arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- arch/x86/ia32/ia32_signal.c | 21 +- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/entry-common.h | 3 + arch/x86/include/asm/event-type.h | 17 ++ arch/x86/include/asm/extable_fixup_types.h | 4 +- arch/x86/include/asm/fred.h | 131 ++++++++++ arch/x86/include/asm/idtentry.h | 68 ++++- arch/x86/include/asm/irq.h | 5 + arch/x86/include/asm/irq_vectors.h | 15 +- arch/x86/include/asm/msr-index.h | 12 +- arch/x86/include/asm/processor.h | 12 +- arch/x86/include/asm/ptrace.h | 36 ++- arch/x86/include/asm/switch_to.h | 10 +- arch/x86/include/asm/thread_info.h | 35 +-- arch/x86/include/asm/traps.h | 15 ++ arch/x86/include/asm/vmx.h | 17 +- arch/x86/include/uapi/asm/processor-flags.h | 2 + arch/x86/kernel/Makefile | 1 + arch/x86/kernel/apic/apic.c | 11 +- arch/x86/kernel/apic/vector.c | 8 +- arch/x86/kernel/cpu/acrn.c | 7 +- arch/x86/kernel/cpu/common.c | 88 ++++--- arch/x86/kernel/cpu/mce/core.c | 11 + arch/x86/kernel/cpu/mshyperv.c | 22 +- arch/x86/kernel/espfix_64.c | 8 + arch/x86/kernel/fred.c | 73 ++++++ arch/x86/kernel/head_32.S | 3 +- arch/x86/kernel/idt.c | 6 +- arch/x86/kernel/irq.c | 6 +- arch/x86/kernel/irqinit.c | 7 +- arch/x86/kernel/kvm.c | 4 +- arch/x86/kernel/nmi.c | 28 +++ arch/x86/kernel/process.c | 5 + arch/x86/kernel/process_64.c | 21 +- arch/x86/kernel/traps.c | 175 +++++++++++-- arch/x86/lib/x86-opcode-map.txt | 2 +- arch/x86/mm/extable.c | 28 +++ arch/x86/mm/fault.c | 20 +- drivers/xen/events/events_base.c | 5 +- kernel/fork.c | 6 + tools/arch/x86/include/asm/cpufeatures.h | 1 + .../arch/x86/include/asm/disabled-features.h | 8 +- tools/arch/x86/include/asm/msr-index.h | 12 +- tools/arch/x86/lib/x86-opcode-map.txt | 2 +- tools/objtool/arch/x86/decode.c | 22 +- 54 files changed, 1148 insertions(+), 173 deletions(-) create mode 100644 arch/x86/entry/entry_64_fred.S create mode 100644 arch/x86/entry/entry_fred.c create mode 100644 arch/x86/include/asm/event-type.h create mode 100644 arch/x86/include/asm/fred.h create mode 100644 arch/x86/kernel/fred.c