From patchwork Thu Sep 14 04:47:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13384454 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 5A8AFEDE98B for ; Thu, 14 Sep 2023 05:19:36 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.601782.938040 (Exim 4.92) (envelope-from ) id 1qgelC-0003gl-LE; Thu, 14 Sep 2023 05:19:26 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 601782.938040; Thu, 14 Sep 2023 05:19:26 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1qgelC-0003bG-6s; Thu, 14 Sep 2023 05:19:26 +0000 Received: by outflank-mailman (input) for mailman id 601782; Thu, 14 Sep 2023 05:19:23 +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 1qgel9-0001XI-By for xen-devel@lists.xenproject.org; Thu, 14 Sep 2023 05:19:23 +0000 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.65]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id 4296e55e-52be-11ee-9b0d-b553b5be7939; Thu, 14 Sep 2023 07:19:21 +0200 (CEST) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Sep 2023 22:17:34 -0700 Received: from unknown (HELO fred..) ([172.25.112.68]) by orsmga001.jf.intel.com with ESMTP; 13 Sep 2023 22:17:34 -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: 4296e55e-52be-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=1694668761; x=1726204761; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=kFEO+uu6A5ft6HNZsGdUlo7JkWRDUia/sG5iL2BNrkQ=; b=b4rKuNUl8LwkD03YKrGx/d+ZtCDLf56FpkWw21hv/Cj8yVaxcxhxi5KA qtbiNaindmvtYuxIaB/d/bBsBLlYGmtkLmx95K6ggHKWYjb39SOzbkrFc rcZ4PYT8jxxtYRTCC+wkShHE9iin50nsBt7FlMC3c8IoucDxKJ0dQ63nO Sit7x9a3EfksyPef5Jj30vmJcMC6ApMm6IerYrR2aT7V4AC0pjFAUHG+m uMwNBvQvZV1VzlfkSPv7XUojKjCt3/DD/JfD8sSRE3y4DBWZfiZZHEkzh lgyVOmdxmF3LmISv+4141oY8TLoDhQHdzBEU7LCcNK7JfVQSPTLMxcgw4 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10832"; a="382661196" X-IronPort-AV: E=Sophos;i="6.02,145,1688454000"; d="scan'208";a="382661196" X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10832"; a="779488767" X-IronPort-AV: E=Sophos;i="6.02,145,1688454000"; d="scan'208";a="779488767" 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 Subject: [PATCH v10 10/38] x86/fred: Disable FRED by default in its early stage Date: Wed, 13 Sep 2023 21:47:37 -0700 Message-Id: <20230914044805.301390-11-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230914044805.301390-1-xin3.li@intel.com> References: <20230914044805.301390-1-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 0a1731a0f0ef..42def5cc7552 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 382d4e6b848d..317b4877e9c7 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1486,6 +1486,9 @@ 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