From nobody Mon Feb 9 23:38:22 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 BF57EEB64DC for ; Mon, 17 Jul 2023 23:15:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231316AbjGQXPq (ORCPT ); Mon, 17 Jul 2023 19:15:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35168 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229470AbjGQXPj (ORCPT ); Mon, 17 Jul 2023 19:15:39 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5072B198B for ; Mon, 17 Jul 2023 16:15:00 -0700 (PDT) Message-ID: <20230717223223.971994770@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1689635697; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=8u5DJ4HOBNg4NQW33fRGAZF4EOI10KBFaQA+4tROpKs=; b=QLI6o7zZfUJ6uEVO0T/AOaNQcFm6gfKddASqWmV7W5RXFSwy+nUSFe+jExElnmyMygYN6h O+A5BETXOY1qqqEmS9oY4XobPnGU8HRsrbtcHv5Dn94m867kCJI7J+ttmS9qV65vU6Vssm FsumQO6gxgYEnklbeiHdvqw0/jtVCo/zvPRZ9UXkKY2VfzJlu/StHZP59Sn0pHK3a8g24R BjRFse4HgOgghai1BtadP3xVsgPMXnCBCavZHPnwdRl+ZHOfRdGz/Ev2KB4az9ANz9MAnQ FKYADvdw62f6MK9bCryiUKZcK/pPQbhyeq/Ju/O8+m534u8J+HoKFD3u44SOuQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1689635697; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=8u5DJ4HOBNg4NQW33fRGAZF4EOI10KBFaQA+4tROpKs=; b=6oIKa1QrGezq5SuZ1jAJQe+seQVOmDV0SoWdTq18WSUjH1qD+gBOI2S4ha/qprGXeVBtCz C8rL0lbTGf5dxABA== From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Linus Torvalds , Andrew Cooper , Tom Lendacky , Paolo Bonzini , Wei Liu , Arjan van de Ven , Juergen Gross Subject: [patch 15/58] x86/apic: Sanitize APIC address setup References: <20230717223049.327865981@linutronix.de> MIME-Version: 1.0 Date: Tue, 18 Jul 2023 01:14:57 +0200 (CEST) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Convert places which just write mp_lapic_addr and let them register the local APIC address directly instead of relying on magic other code to do so. Add a WARN_ON() into register_lapic_address() which is raised when register_lapic_address() is invoked more than once during boot. Signed-off-by: Thomas Gleixner --- arch/x86/kernel/apic/apic.c | 25 ++++++++----------------- 1 file changed, 8 insertions(+), 17 deletions(-) --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -2009,12 +2009,12 @@ static bool __init detect_init_APIC(void return false; } =20 - mp_lapic_addr =3D APIC_DEFAULT_PHYS_BASE; + register_lapic_address(APIC_DEFAULT_PHYS_BASE); return true; } #else =20 -static bool __init apic_verify(void) +static bool __init apic_verify(unsigned long addr) { u32 features, h, l; =20 @@ -2028,15 +2028,15 @@ static bool __init apic_verify(void) return false; } set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC); - mp_lapic_addr =3D APIC_DEFAULT_PHYS_BASE; =20 /* The BIOS may have set up the APIC at some other address */ if (boot_cpu_data.x86 >=3D 6) { rdmsr(MSR_IA32_APICBASE, l, h); if (l & MSR_IA32_APICBASE_ENABLE) - mp_lapic_addr =3D l & MSR_IA32_APICBASE_BASE; + addr =3D l & MSR_IA32_APICBASE_BASE; } =20 + register_lapic_address(addr); pr_info("Found and enabled local APIC!\n"); return true; } @@ -2063,7 +2063,7 @@ bool __init apic_force_enable(unsigned l enabled_via_apicbase =3D 1; } } - return apic_verify(); + return apic_verify(addr); } =20 /* @@ -2105,7 +2105,7 @@ static bool __init detect_init_APIC(void if (!apic_force_enable(APIC_DEFAULT_PHYS_BASE)) return false; } else { - if (!apic_verify()) + if (!apic_verify(APIC_DEFAULT_PHYS_BASE)) return false; } =20 @@ -2130,20 +2130,9 @@ void __init init_apic_mappings(void) if (x2apic_mode) return; =20 - /* If no local APIC can be found return early */ if (!smp_found_config && !detect_init_APIC()) { - /* lets NOP'ify apic operations */ pr_info("APIC: disable apic facility\n"); apic_disable(); - } else { - apic_phys =3D mp_lapic_addr; - - /* - * If the system has ACPI MADT tables or MP info, the LAPIC - * address is already registered. - */ - if (!acpi_lapic && !smp_found_config) - register_lapic_address(apic_phys); } } =20 @@ -2158,6 +2147,8 @@ static __init void apic_set_fixmap(void) =20 void __init register_lapic_address(unsigned long address) { + /* This should only happen once */ + WARN_ON_ONCE(mp_lapic_addr); mp_lapic_addr =3D address; =20 if (!x2apic_mode)