From patchwork Fri Feb 3 13:50:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 13127663 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 CF854C636D6 for ; Fri, 3 Feb 2023 14:06:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233645AbjBCOGD (ORCPT ); Fri, 3 Feb 2023 09:06:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48976 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233948AbjBCOFP (ORCPT ); Fri, 3 Feb 2023 09:05:15 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 26B32A58FB; Fri, 3 Feb 2023 06:02:41 -0800 (PST) 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 10775165C; Fri, 3 Feb 2023 05:53:56 -0800 (PST) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.1.196.177]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 429563F71E; Fri, 3 Feb 2023 05:53:10 -0800 (PST) From: James Morse To: linux-pm@vger.kernel.org, loongarch@lists.linux.dev, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-acpi@vger.kernel.org, linux-arch@vger.kernel.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org Cc: Marc Zyngier , Thomas Gleixner , Lorenzo Pieralisi , Mark Rutland , Sudeep Holla , Borislav Petkov , H Peter Anvin , Dave Hansen , Ingo Molnar , Will Deacon , Catalin Marinas , Huacai Chen , James Morse , Suzuki K Poulose , Oliver Upton , Len Brown , Rafael Wysocki , WANG Xuerui , Salil Mehta , Russell King , Jean-Philippe Brucker Subject: [RFC PATCH 19/32] ACPI: Warn when the present bit changes but the feature is not enabled Date: Fri, 3 Feb 2023 13:50:30 +0000 Message-Id: <20230203135043.409192-20-james.morse@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230203135043.409192-1-james.morse@arm.com> References: <20230203135043.409192-1-james.morse@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org ACPI firmware can trigger the events to add and remove CPUs, but the OS may not support this. Print a warning when this happens. This gives early warning on arm64 systems that don't support CONFIG_ACPI_HOTPLUG_PRESENT_CPU, as making CPUs not present has side effects for other parts of the system. Signed-off-by: James Morse --- drivers/acpi/acpi_processor.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index e6419b06cb37..572a12672c0e 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -155,8 +155,10 @@ static int acpi_processor_make_present(struct acpi_processor *pr) acpi_status status; int ret; - if (!IS_ENABLED(CONFIG_ACPI_HOTPLUG_PRESENT_CPU)) + if (!IS_ENABLED(CONFIG_ACPI_HOTPLUG_PRESENT_CPU)) { + pr_err_once("Changing CPU present bit is not supported\n"); return -ENODEV; + } if (invalid_phys_cpuid(pr->phys_id)) return -ENODEV; @@ -414,8 +416,10 @@ static void acpi_processor_make_not_present(struct acpi_device *device) { struct acpi_processor *pr; - if (!IS_ENABLED(CONFIG_ACPI_HOTPLUG_PRESENT_CPU)) + if (!IS_ENABLED(CONFIG_ACPI_HOTPLUG_PRESENT_CPU)) { + pr_err_once("Changing CPU present bit is not supported"); return; + } pr = acpi_driver_data(device); if (pr->id >= nr_cpu_ids)