From nobody Wed Dec 17 09:44:30 2025 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 A6CCBC0032E for ; Fri, 20 Oct 2023 15:13:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377659AbjJTPNF (ORCPT ); Fri, 20 Oct 2023 11:13:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57558 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377644AbjJTPNA (ORCPT ); Fri, 20 Oct 2023 11:13:00 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED9D2D68 for ; Fri, 20 Oct 2023 08:12:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1697814777; x=1729350777; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=firllW6b4HjSWBx4+iNxoACpTQ91miOAH8oT/GYrPv4=; b=G17GDNbSAN9vVAHVv31bqdmHG37Aa1H9jjedBnhF1yDA/n+PkqpLNBhP pgtV7t5w+OGwWEzoLUoOQ7aRa+TU+n57OKOQjNl8PR2TZ82BE7xMxoLy+ pwj6q7shDpYbBeyjbHJiPgetFbSNIlLysD29gYT36F+rsKUxDQ9XhIv2R CBvRcxHF3IBcL/WxwoXAW4Gwcwz64xq6CsIDYk+TS7WMcyWzQqNAS+bvh m2JTPqJuc/g1QkZluFlirUrU9XJYwL0FbnQXR+T6MyXk9KJfi4NsPbRnp hjHRVa6LgUK9hCMhqp5CpDJvjU8uwUnFQyxI9WvMDfVNu1skYhCWGDGDC g==; X-IronPort-AV: E=McAfee;i="6600,9927,10869"; a="376893601" X-IronPort-AV: E=Sophos;i="6.03,239,1694761200"; d="scan'208";a="376893601" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2023 08:12:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10869"; a="761080247" X-IronPort-AV: E=Sophos;i="6.03,239,1694761200"; d="scan'208";a="761080247" Received: from dgutows1-mobl.ger.corp.intel.com (HELO box.shutemov.name) ([10.249.39.237]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Oct 2023 08:12:48 -0700 Received: by box.shutemov.name (Postfix, from userid 1000) id E65D910A293; Fri, 20 Oct 2023 18:12:44 +0300 (+03) From: "Kirill A. Shutemov" To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org Cc: "Rafael J. Wysocki" , Peter Zijlstra , Adrian Hunter , Kuppuswamy Sathyanarayanan , Elena Reshetova , Jun Nakajima , Rick Edgecombe , Tom Lendacky , "Kalra, Ashish" , Sean Christopherson , "Huang, Kai" , Baoquan He , kexec@lists.infradead.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv2 01/13] x86/acpi: Extract ACPI MADT wakeup code into a separate file Date: Fri, 20 Oct 2023 18:12:30 +0300 Message-ID: <20231020151242.1814-2-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231020151242.1814-1-kirill.shutemov@linux.intel.com> References: <20231020151242.1814-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In order to prepare for the expansion of support for the ACPI MADT wakeup method, move the relevant code into a separate file. Introduce a new configuration option to clearly indicate dependencies without the use of ifdefs. There have been no functional changes. Signed-off-by: Kirill A. Shutemov Reviewed-by: Kuppuswamy Sathyanarayanan --- arch/x86/Kconfig | 7 +++ arch/x86/include/asm/acpi.h | 5 ++ arch/x86/kernel/acpi/Makefile | 11 ++-- arch/x86/kernel/acpi/boot.c | 86 +----------------------------- arch/x86/kernel/acpi/madt_wakeup.c | 81 ++++++++++++++++++++++++++++ 5 files changed, 100 insertions(+), 90 deletions(-) create mode 100644 arch/x86/kernel/acpi/madt_wakeup.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 799102f4d909..9957a73bb386 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1108,6 +1108,13 @@ config X86_LOCAL_APIC depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI select IRQ_DOMAIN_HIERARCHY =20 +config X86_ACPI_MADT_WAKEUP + def_bool y + depends on X86_64 + depends on ACPI + depends on SMP + depends on X86_LOCAL_APIC + config X86_IO_APIC def_bool y depends on X86_LOCAL_APIC || X86_UP_IOAPIC diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h index c8a7fc23f63c..b536b5a6a57b 100644 --- a/arch/x86/include/asm/acpi.h +++ b/arch/x86/include/asm/acpi.h @@ -73,6 +73,11 @@ static inline bool acpi_skip_set_wakeup_address(void) =20 #define acpi_skip_set_wakeup_address acpi_skip_set_wakeup_address =20 +union acpi_subtable_headers; + +int __init acpi_parse_mp_wake(union acpi_subtable_headers *header, + const unsigned long end); + /* * Check if the CPU can handle C2 and deeper */ diff --git a/arch/x86/kernel/acpi/Makefile b/arch/x86/kernel/acpi/Makefile index fc17b3f136fe..8c7329c88a75 100644 --- a/arch/x86/kernel/acpi/Makefile +++ b/arch/x86/kernel/acpi/Makefile @@ -1,11 +1,12 @@ # SPDX-License-Identifier: GPL-2.0 =20 -obj-$(CONFIG_ACPI) +=3D boot.o -obj-$(CONFIG_ACPI_SLEEP) +=3D sleep.o wakeup_$(BITS).o -obj-$(CONFIG_ACPI_APEI) +=3D apei.o -obj-$(CONFIG_ACPI_CPPC_LIB) +=3D cppc.o +obj-$(CONFIG_ACPI) +=3D boot.o +obj-$(CONFIG_ACPI_SLEEP) +=3D sleep.o wakeup_$(BITS).o +obj-$(CONFIG_ACPI_APEI) +=3D apei.o +obj-$(CONFIG_ACPI_CPPC_LIB) +=3D cppc.o +obj-$(CONFIG_X86_ACPI_MADT_WAKEUP) +=3D madt_wakeup.o =20 ifneq ($(CONFIG_ACPI_PROCESSOR),) -obj-y +=3D cstate.o +obj-y +=3D cstate.o endif =20 diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 2a0ea38955df..111bd226ad99 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -66,13 +66,6 @@ static u64 acpi_lapic_addr __initdata =3D APIC_DEFAULT_P= HYS_BASE; static bool acpi_support_online_capable; #endif =20 -#ifdef CONFIG_X86_64 -/* Physical address of the Multiprocessor Wakeup Structure mailbox */ -static u64 acpi_mp_wake_mailbox_paddr; -/* Virtual address of the Multiprocessor Wakeup Structure mailbox */ -static struct acpi_madt_multiproc_wakeup_mailbox *acpi_mp_wake_mailbox; -#endif - #ifdef CONFIG_X86_IO_APIC /* * Locks related to IOAPIC hotplug @@ -357,60 +350,6 @@ acpi_parse_lapic_nmi(union acpi_subtable_headers * hea= der, const unsigned long e =20 return 0; } - -#ifdef CONFIG_X86_64 -static int acpi_wakeup_cpu(int apicid, unsigned long start_ip) -{ - /* - * Remap mailbox memory only for the first call to acpi_wakeup_cpu(). - * - * Wakeup of secondary CPUs is fully serialized in the core code. - * No need to protect acpi_mp_wake_mailbox from concurrent accesses. - */ - if (!acpi_mp_wake_mailbox) { - acpi_mp_wake_mailbox =3D memremap(acpi_mp_wake_mailbox_paddr, - sizeof(*acpi_mp_wake_mailbox), - MEMREMAP_WB); - } - - /* - * Mailbox memory is shared between the firmware and OS. Firmware will - * listen on mailbox command address, and once it receives the wakeup - * command, the CPU associated with the given apicid will be booted. - * - * The value of 'apic_id' and 'wakeup_vector' must be visible to the - * firmware before the wakeup command is visible. smp_store_release() - * ensures ordering and visibility. - */ - acpi_mp_wake_mailbox->apic_id =3D apicid; - acpi_mp_wake_mailbox->wakeup_vector =3D start_ip; - smp_store_release(&acpi_mp_wake_mailbox->command, - ACPI_MP_WAKE_COMMAND_WAKEUP); - - /* - * Wait for the CPU to wake up. - * - * The CPU being woken up is essentially in a spin loop waiting to be - * woken up. It should not take long for it wake up and acknowledge by - * zeroing out ->command. - * - * ACPI specification doesn't provide any guidance on how long kernel - * has to wait for a wake up acknowledgement. It also doesn't provide - * a way to cancel a wake up request if it takes too long. - * - * In TDX environment, the VMM has control over how long it takes to - * wake up secondary. It can postpone scheduling secondary vCPU - * indefinitely. Giving up on wake up request and reporting error opens - * possible attack vector for VMM: it can wake up a secondary CPU when - * kernel doesn't expect it. Wait until positive result of the wake up - * request. - */ - while (READ_ONCE(acpi_mp_wake_mailbox->command)) - cpu_relax(); - - return 0; -} -#endif /* CONFIG_X86_64 */ #endif /* CONFIG_X86_LOCAL_APIC */ =20 #ifdef CONFIG_X86_IO_APIC @@ -1160,29 +1099,6 @@ static int __init acpi_parse_madt_lapic_entries(void) } return 0; } - -#ifdef CONFIG_X86_64 -static int __init acpi_parse_mp_wake(union acpi_subtable_headers *header, - const unsigned long end) -{ - struct acpi_madt_multiproc_wakeup *mp_wake; - - if (!IS_ENABLED(CONFIG_SMP)) - return -ENODEV; - - mp_wake =3D (struct acpi_madt_multiproc_wakeup *)header; - if (BAD_MADT_ENTRY(mp_wake, end)) - return -EINVAL; - - acpi_table_print_madt_entry(&header->common); - - acpi_mp_wake_mailbox_paddr =3D mp_wake->base_address; - - apic_update_callback(wakeup_secondary_cpu_64, acpi_wakeup_cpu); - - return 0; -} -#endif /* CONFIG_X86_64 */ #endif /* CONFIG_X86_LOCAL_APIC */ =20 #ifdef CONFIG_X86_IO_APIC @@ -1379,7 +1295,7 @@ static void __init acpi_process_madt(void) smp_found_config =3D 1; } =20 -#ifdef CONFIG_X86_64 +#ifdef CONFIG_X86_ACPI_MADT_WAKEUP /* * Parse MADT MP Wake entry. */ diff --git a/arch/x86/kernel/acpi/madt_wakeup.c b/arch/x86/kernel/acpi/madt= _wakeup.c new file mode 100644 index 000000000000..58cdfc0b6c0a --- /dev/null +++ b/arch/x86/kernel/acpi/madt_wakeup.c @@ -0,0 +1,81 @@ +#include +#include +#include +#include +#include + +/* Physical address of the Multiprocessor Wakeup Structure mailbox */ +static u64 acpi_mp_wake_mailbox_paddr; + +/* Virtual address of the Multiprocessor Wakeup Structure mailbox */ +static struct acpi_madt_multiproc_wakeup_mailbox *acpi_mp_wake_mailbox; + +static int acpi_wakeup_cpu(int apicid, unsigned long start_ip) +{ + /* + * Remap mailbox memory only for the first call to acpi_wakeup_cpu(). + * + * Wakeup of secondary CPUs is fully serialized in the core code. + * No need to protect acpi_mp_wake_mailbox from concurrent accesses. + */ + if (!acpi_mp_wake_mailbox) { + acpi_mp_wake_mailbox =3D memremap(acpi_mp_wake_mailbox_paddr, + sizeof(*acpi_mp_wake_mailbox), + MEMREMAP_WB); + } + + /* + * Mailbox memory is shared between the firmware and OS. Firmware will + * listen on mailbox command address, and once it receives the wakeup + * command, the CPU associated with the given apicid will be booted. + * + * The value of 'apic_id' and 'wakeup_vector' must be visible to the + * firmware before the wakeup command is visible. smp_store_release() + * ensures ordering and visibility. + */ + acpi_mp_wake_mailbox->apic_id =3D apicid; + acpi_mp_wake_mailbox->wakeup_vector =3D start_ip; + smp_store_release(&acpi_mp_wake_mailbox->command, + ACPI_MP_WAKE_COMMAND_WAKEUP); + + /* + * Wait for the CPU to wake up. + * + * The CPU being woken up is essentially in a spin loop waiting to be + * woken up. It should not take long for it wake up and acknowledge by + * zeroing out ->command. + * + * ACPI specification doesn't provide any guidance on how long kernel + * has to wait for a wake up acknowledgement. It also doesn't provide + * a way to cancel a wake up request if it takes too long. + * + * In TDX environment, the VMM has control over how long it takes to + * wake up secondary. It can postpone scheduling secondary vCPU + * indefinitely. Giving up on wake up request and reporting error opens + * possible attack vector for VMM: it can wake up a secondary CPU when + * kernel doesn't expect it. Wait until positive result of the wake up + * request. + */ + while (READ_ONCE(acpi_mp_wake_mailbox->command)) + cpu_relax(); + + return 0; +} + +int __init acpi_parse_mp_wake(union acpi_subtable_headers *header, + const unsigned long end) +{ + struct acpi_madt_multiproc_wakeup *mp_wake; + + mp_wake =3D (struct acpi_madt_multiproc_wakeup *)header; + if (BAD_MADT_ENTRY(mp_wake, end)) + return -EINVAL; + + acpi_table_print_madt_entry(&header->common); + + acpi_mp_wake_mailbox_paddr =3D mp_wake->base_address; + + apic_update_callback(wakeup_secondary_cpu_64, acpi_wakeup_cpu); + + return 0; +} --=20 2.41.0