From patchwork Tue Dec 5 10:49:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13479978 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D4B61C07E97 for ; Tue, 5 Dec 2023 11:22:15 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.647563.1010875 (Exim 4.92) (envelope-from ) id 1rATUa-0005K8-HW; Tue, 05 Dec 2023 11:21:32 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 647563.1010875; Tue, 05 Dec 2023 11:21:32 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rATUa-0005II-BS; Tue, 05 Dec 2023 11:21:32 +0000 Received: by outflank-mailman (input) for mailman id 647563; Tue, 05 Dec 2023 11:21:31 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rATUY-0003dP-TA for xen-devel@lists.xenproject.org; Tue, 05 Dec 2023 11:21:30 +0000 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 6d9637ad-9360-11ee-9b0f-b553b5be7939; Tue, 05 Dec 2023 12:21:26 +0100 (CET) Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Dec 2023 03:21:19 -0800 Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga006.fm.intel.com with ESMTP; 05 Dec 2023 03:21:18 -0800 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 6d9637ad-9360-11ee-9b0f-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1701775287; x=1733311287; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=at3P90/0BHfZm4A3RDkp4mmTPKN/FQQ6JC7gRORtMwU=; b=Hi9+qqrSRYSHE/bzr39tBZYAb7pb7u5HtKapuGTBoHQ2eQB03Nqb5Rcb WmVB16Zdd3UnYH0myD/ofUhh46kNNIlFlCtCI7fUh2hBGX5qMjIJHfllD 2kNmZh8VTRZtlINDOjUX1mPsEhq9wru1h87egoPoex4LtBylCn7ARRJMj rVQnfqH5IcFwDjwndokZOEBw1LtkMcUDkIt33qu7EDikg8dUYT9rQhlym NG4H9ROyKMYovwEHlc2hwxPP9ASzhAGXMv6MVdOXBgjcS86yatZyE2Svl BvQv05wAzzwUUH771WwfDwAr6efYOaY9QWkIXzcABzunm+9Utc3bYEX4c Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10914"; a="942402" X-IronPort-AV: E=Sophos;i="6.04,252,1695711600"; d="scan'208";a="942402" X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10914"; a="1018192924" X-IronPort-AV: E=Sophos;i="6.04,252,1695711600"; d="scan'208";a="1018192924" From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com, shan.kang@intel.com Subject: [PATCH v13 08/35] x86/fred: Disable FRED by default in its early stage Date: Tue, 5 Dec 2023 02:49:57 -0800 Message-ID: <20231205105030.8698-9-xin3.li@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231205105030.8698-1-xin3.li@intel.com> References: <20231205105030.8698-1-xin3.li@intel.com> MIME-Version: 1.0 To enable FRED, a new kernel command line option "fred" needs to be added. Tested-by: Shan Kang Signed-off-by: Xin Li --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ arch/x86/kernel/cpu/common.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 65731b060e3f..6992b392e8d3 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1526,6 +1526,9 @@ Warning: use of this parameter will taint the kernel and may cause unknown problems. + fred [X86-64] + Enable flexible return and event delivery + ftrace=[tracer] [FTRACE] will set and start the specified tracer as early as possible in order to facilitate early diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 4d4b87c6885d..68102acd63b0 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1491,6 +1491,9 @@ static void __init cpu_parse_early_param(void) char *argptr = arg, *opt; int arglen, taint = 0; + if (!cmdline_find_option_bool(boot_command_line, "fred")) + setup_clear_cpu_cap(X86_FEATURE_FRED); + #ifdef CONFIG_X86_32 if (cmdline_find_option_bool(boot_command_line, "no387")) #ifdef CONFIG_MATH_EMULATION