From patchwork Fri Apr 26 13:51:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 792843 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B07861487E6; Fri, 26 Apr 2024 13:57:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714139862; cv=none; b=eq4s1zS4p1+IiUu+0NvTyaO2onZEUjh2MzLtsVvOueUbG8P0zr+sDy9JDh7A0fd3WmgSa6PkNbNYe886LLJ6LC7ukcVc4bTI8TkqH19ygfodwghhmwslNz/uK8+uLMZHNcG/OsujWM95S8ioX41TUDs1uTcRQPvBXtH07/RyxHM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714139862; c=relaxed/simple; bh=dHTHd6agazxCncDtB5eXXAKR0X/5llvllP9Zv6vm8FA=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Mc0ggN5BO7MFamEnWT7M8Y84RjjwZVoOGWnZSBVlYj1cJz+k+4Td7Z2jJAXH/gnS5kB3IqXPA7kGYTHfER8nNYPcuNotacLJLmcoKQXaZ5iZDDk4DJyKEJvw6FiPcwWk9zVA+tIZk80N4jyHRpqAamHoWkDzNKITSsn9UdJVIQM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.231]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4VQvP86D31z6K6Z3; Fri, 26 Apr 2024 21:55:08 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id 94325140A36; Fri, 26 Apr 2024 21:57:37 +0800 (CST) Received: from SecurePC-101-06.china.huawei.com (10.122.247.231) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Fri, 26 Apr 2024 14:57:36 +0100 From: Jonathan Cameron To: Thomas Gleixner , Peter Zijlstra , , , , , , , , , Russell King , "Rafael J . Wysocki" , Miguel Luis , James Morse , Salil Mehta , Jean-Philippe Brucker , Catalin Marinas , Will Deacon , Marc Zyngier , Hanjun Guo CC: Ingo Molnar , Borislav Petkov , Dave Hansen , , , , Lorenzo Pieralisi , Sudeep Holla Subject: [PATCH v8 12/16] arm64: psci: Ignore DENIED CPUs Date: Fri, 26 Apr 2024 14:51:22 +0100 Message-ID: <20240426135126.12802-13-Jonathan.Cameron@huawei.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240426135126.12802-1-Jonathan.Cameron@huawei.com> References: <20240426135126.12802-1-Jonathan.Cameron@huawei.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: lhrpeml500002.china.huawei.com (7.191.160.78) To lhrpeml500005.china.huawei.com (7.191.163.240) From: Jean-Philippe Brucker When a CPU is marked as disabled, but online capable in the MADT, PSCI applies some firmware policy to control when it can be brought online. PSCI returns DENIED to a CPU_ON request if this is not currently permitted. The OS can learn the current policy from the _STA enabled bit. Handle the PSCI DENIED return code gracefully instead of printing an error. Note the alternatives to the PSCI cpu_boot() callback do not return -EPERM so the change in smp.c has no affect. See https://developer.arm.com/documentation/den0022/f/?lang=en page 58. Signed-off-by: Jean-Philippe Brucker [ morse: Rewrote commit message ] Signed-off-by: James Morse Tested-by: Miguel Luis Tested-by: Vishnu Pajjuri Tested-by: Jianyong Wu Reviewed-by: Jonathan Cameron Signed-off-by: Russell King (Oracle) Signed-off-by: Jonathan Cameron Reviewed-by: Gavin Shan --- v8: Note in commit message that the -EPERM guard on the error print only affects PSCI as other options never use this error code. Should they do so in future, that may well indicate that they now support similar refusal to boot. --- arch/arm64/kernel/psci.c | 2 +- arch/arm64/kernel/smp.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 29a8e444db83..fabd732d0a2d 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -40,7 +40,7 @@ static int cpu_psci_cpu_boot(unsigned int cpu) { phys_addr_t pa_secondary_entry = __pa_symbol(secondary_entry); int err = psci_ops.cpu_on(cpu_logical_map(cpu), pa_secondary_entry); - if (err) + if (err && err != -EPERM) pr_err("failed to boot CPU%d (%d)\n", cpu, err); return err; diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 4ced34f62dab..dc0e0b3ec2d4 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -132,7 +132,8 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) /* Now bring the CPU into our world */ ret = boot_secondary(cpu, idle); if (ret) { - pr_err("CPU%u: failed to boot: %d\n", cpu, ret); + if (ret != -EPERM) + pr_err("CPU%u: failed to boot: %d\n", cpu, ret); return ret; }