From patchwork Tue Oct 3 06:24:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13406810 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 591D1E7542C for ; Tue, 3 Oct 2023 06:55:03 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.611899.951614 (Exim 4.92) (envelope-from ) id 1qnZIy-0006WF-1i; Tue, 03 Oct 2023 06:54:52 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 611899.951614; Tue, 03 Oct 2023 06:54:51 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qnZIx-0006UD-Lj; Tue, 03 Oct 2023 06:54:51 +0000 Received: by outflank-mailman (input) for mailman id 611899; Tue, 03 Oct 2023 06:54:49 +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 1qnZIu-00047B-Qi for xen-devel@lists.xenproject.org; Tue, 03 Oct 2023 06:54:48 +0000 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id bcddf705-61b9-11ee-9b0d-b553b5be7939; Tue, 03 Oct 2023 08:54:46 +0200 (CEST) Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Oct 2023 23:54:40 -0700 Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga005.fm.intel.com with ESMTP; 02 Oct 2023 23:54:39 -0700 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: bcddf705-61b9-11ee-9b0d-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696316086; x=1727852086; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=aQdiRWsnt6AKxUkiRSvWlc5kg1W+wRYx8vYlgG3sGOg=; b=jQMHxIr1oVjfOZtw/8jMxocgpY2cAuYuyM/rAeFx3lUNmwBJXTexx4we aFWhbRCxnbLXKj9IpWB8Rt/jeY3cEwMcJCEaReVHG0PM6qThJ7dTR7Eip 8uPf0E0dvvPQasuEMww97/okLMnLnuBitQddurSzwCeD/936bcgwhZhoC QMCdRWD7YaBQ1MwlZ28m8S3ksY0KYDKGX7IpjmwDdqrknVP2VGyqQ9ixN D2CTAFHgrwTbvVhMBW/3KqaRKlGCM7Vvmh3jeVGATlljOQdpzQlrb+pxh r3FEwotvAMX71fTkpFs5Tiz3kQ88GD6LdbRkx+xgAdykiWJ1Vd7PmD/fC g==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="367858016" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="367858016" X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1081900925" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1081900925" 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 Subject: [PATCH v12 10/37] x86/fred: Disable FRED by default in its early stage Date: Mon, 2 Oct 2023 23:24:31 -0700 Message-Id: <20231003062458.23552-11-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231003062458.23552-1-xin3.li@intel.com> References: <20231003062458.23552-1-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 45e34be4ed56..ee939ea00458 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1525,6 +1525,9 @@ 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 7131074433f9..736d38abfc5a 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1502,6 +1502,9 @@ 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