From patchwork Wed Sep 13 16:38:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 722144 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 92D54EE01E0 for ; Wed, 13 Sep 2023 16:41:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230364AbjIMQlU (ORCPT ); Wed, 13 Sep 2023 12:41:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230437AbjIMQkO (ORCPT ); Wed, 13 Sep 2023 12:40:14 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 7F2B126A4; Wed, 13 Sep 2023 09:39:39 -0700 (PDT) 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 59BDAFEC; Wed, 13 Sep 2023 09:40:16 -0700 (PDT) Received: from merodach.members.linode.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5ED3D3F5A1; Wed, 13 Sep 2023 09:39:37 -0700 (PDT) From: James Morse To: linux-pm@vger.kernel.org, loongarch@lists.linux.dev, linux-acpi@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, kvmarm@lists.linux.dev Cc: x86@kernel.org, Salil Mehta , Russell King , Jean-Philippe Brucker , jianyong.wu@arm.com, justin.he@arm.com Subject: [RFC PATCH v2 23/35] ACPI: Warn when the present bit changes but the feature is not enabled Date: Wed, 13 Sep 2023 16:38:11 +0000 Message-Id: <20230913163823.7880-24-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230913163823.7880-1-james.morse@arm.com> References: <20230913163823.7880-1-james.morse@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@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 Reviewed-by: Jonathan Cameron Reviewed-by: Gavin Shan --- 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 2cafea1edc24..b67616079751 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -188,8 +188,10 @@ 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; @@ -462,8 +464,10 @@ 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)