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([172.25.112.68]) by fmsmga008.fm.intel.com with ESMTP; 23 Sep 2023 03:11:40 -0700 X-Outflank-Mailman: Message body and most headers restored to incoming version 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: 9b86a226-59f9-11ee-9b0d-b553b5be7939 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695463908; x=1726999908; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=8L4dZHWPEow2ZsckWCTENKztBfQe3j0MHQV1pASC0Y8=; b=lL1xZ85NSL8Gwct/7lwhDiZukUN9gEsZ/DQ+VT5BtJ/sy83tGtLaXe3u spSfvNutpZleO/02PlypJSR0Ojgr/C5qvOMSjc+SU+rlOwxpCEYPs3UCh m0RufCJDT+J3JroRva7JmSIHipf+FHvyA+5gC7WJDn8xpLd8n0El08fk6 d1Ahksldiw8Psll9ctj/xjWDB1WB6gxNDauYBE5W023D/k36t68WxKxNS JtYjPM6CwuuYfrHC/5pFpRvikDjwwzDCaKqPMAMbO6NJzEn8OhPm5hG3v 0sXkwi4CuKWKdQRGJpFdwUMS1fRZYZQ2jwbFn3fqOjEa3y7aAvss0hULX A==; X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="447492192" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="447492192" X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="813388135" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="813388135" 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 v11 10/37] x86/fred: Disable FRED by default in its early stage Date: Sat, 23 Sep 2023 02:41:45 -0700 Message-Id: <20230923094212.26520-11-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230923094212.26520-1-xin3.li@intel.com> References: <20230923094212.26520-1-xin3.li@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @intel.com) X-ZM-MESSAGEID: 1695463944973100007 Content-Type: text/plain; charset="utf-8" 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/Documentatio= n/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. =20 + fred [X86-64] + Enable flexible return and event delivery + ftrace=3D[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 afa755e06ae9..4dec7822a291 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1487,6 +1487,9 @@ static void __init cpu_parse_early_param(void) char *argptr =3D arg, *opt; int arglen, taint =3D 0; =20 + 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 --=20 2.34.1