From patchwork Sat Sep 23 09:41:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 143910 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:cae8:0:b0:403:3b70:6f57 with SMTP id r8csp197500vqu; Sat, 23 Sep 2023 07:07:43 -0700 (PDT) X-Google-Smtp-Source: AGHT+IF8jMhb+JTGxartK5zSYvQ7L19b92Rw+hWnoCLjkm7LdidyEMwqpWQ1R9MLbAzhXd+ZqdfO X-Received: by 2002:a17:902:82c6:b0:1c3:8230:30d8 with SMTP id u6-20020a17090282c600b001c3823030d8mr1951863plz.38.1695478062786; Sat, 23 Sep 2023 07:07:42 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1695478062; cv=none; d=google.com; s=arc-20160816; b=I7yjRMW2q92uqimEyp3T43sCvo2zQl8SqYi8moFcMYfLOWBugTtab+1j2+dUdTyU9N BX6ZvJREiOk0KTaRqFU5OBmD4a3MpBrHJN9TxIrV0Fsit4GP/V6TjyqGQeCq4C9OPD6B oKYT1lcu5/3G7/qPLy7eLPjYGF8WkZT0MkQlpBhn7uen7esJTdaWEsHw2HOoZEZL0Wjh nfn6p/UT7Nxc0bytqcDlOlfM39nivje5An5X3EJU0L0kQvBx8HLkvpv12/7m4kdp3euP I53xZd8pgswpb6BrT88OzkuUdZmNvujgpK0oIW1ZeVVKhjiFGTHxwuR9Y6NPU5L+aWtZ d6nA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=LCRDflOv8BGvouMz/P/NOgPdmMAO4XsG/D55UB1KVew=; fh=Tb1p8S3iOxe/kX/WSNC3xEJzSVgGJ5DaxSrKb+pzH+4=; b=wr1rulTXOv3UZNochQhWxOjyiOk7agaK7bdCuWbnAhXARnoTpyVfuC67XxwpJ4WnLa 14EIaqygGcdMyDFzGgQ71AZySGQQK3KfHe5r1gQzU0EbS5hDo3J1EjdLHkVm/qRDN0E5 TsJfSnDO04+9kdf6GpX0cJnCKQxSrsdmBA6mP0X5Fg5gkJ9sKVSB8bIxtnzKKNe3x2Ik Ddi6eqs9R3flk/cTFC2UOgaRAX25e871CILCNrcJogJJLD/1ki7zhLWbkJmL0dx/PfUo F4IiF4zwT1VcgTbnAneu5k1+qfw9Drf8JBzWW8pIRkK7FXwnBt8WyWRjJkfHVUT3ulQU Dqsw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@intel.com header.s=Intel header.b=RF50qkSp; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: from howler.vger.email (howler.vger.email. [23.128.96.34]) by mx.google.com with ESMTPS id y15-20020a17090322cf00b001c470c25409si6575145plg.327.2023.09.23.07.07.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 23 Sep 2023 07:07:42 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) client-ip=23.128.96.34; Authentication-Results: mx.google.com; dkim=pass header.i=@intel.com header.s=Intel header.b=RF50qkSp; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id C6A6A8605216; Sat, 23 Sep 2023 03:13:11 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at howler.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231779AbjIWKMo (ORCPT + 29 others); Sat, 23 Sep 2023 06:12:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59052 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231474AbjIWKL5 (ORCPT ); Sat, 23 Sep 2023 06:11:57 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C7771BD; Sat, 23 Sep 2023 03:11:48 -0700 (PDT) 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=daicXFK30tmpTUp95RTD2ZQAe5K9xY8zuW1WSEbSaqA=; b=RF50qkSpXHkHvKH70GYJdehu6SU3Tclu7ny+agEjlzZReORO8M5gsxbV 8jDchmx4WmEn33UhCqsX4CjoBXYgdfBdjAmS+HMFbfDBCFPV7eWDoMkGv q/7eEWUDKWJdYTRbV8hzQ2Iz+5sDgKxf+Wv6rMjHbYhdZUa5fWmNndX4Q eXYORjBSws+aAHGQOyrCwmPQ+0yRqv4Rifm2RXtDgJT+SBBlUF4BrgT9f 68LAUNQbSN9Kiu5LqsIlG8OLU6bawp61JmyjAoGzoX/VMBSsWIzUgyZSf WVba+/zSdaJoJcfXH3TAgiA8+siEh/zsn4Rc1T2qwfGaMtmo+rsOhFdBP g==; X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="447492326" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="447492326" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Sep 2023 03:11:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="813388176" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="813388176" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga008.fm.intel.com with ESMTP; 23 Sep 2023 03:11:46 -0700 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 21/37] x86/fred: No ESPFIX needed when FRED is enabled Date: Sat, 23 Sep 2023 02:41:56 -0700 Message-Id: <20230923094212.26520-22-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 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (howler.vger.email [0.0.0.0]); Sat, 23 Sep 2023 03:13:11 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1777837605396193260 X-GMAIL-MSGID: 1777837605396193260 From: "H. Peter Anvin (Intel)" Because FRED always restores the full value of %rsp, ESPFIX is no longer needed when it's enabled. Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Xin Li --- arch/x86/kernel/espfix_64.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c index 16f9814c9be0..6726e0473d0b 100644 --- a/arch/x86/kernel/espfix_64.c +++ b/arch/x86/kernel/espfix_64.c @@ -106,6 +106,10 @@ void __init init_espfix_bsp(void) pgd_t *pgd; p4d_t *p4d; + /* FRED systems always restore the full value of %rsp */ + if (cpu_feature_enabled(X86_FEATURE_FRED)) + return; + /* Install the espfix pud into the kernel page directory */ pgd = &init_top_pgt[pgd_index(ESPFIX_BASE_ADDR)]; p4d = p4d_alloc(&init_mm, pgd, ESPFIX_BASE_ADDR); @@ -129,6 +133,10 @@ void init_espfix_ap(int cpu) void *stack_page; pteval_t ptemask; + /* FRED systems always restore the full value of %rsp */ + if (cpu_feature_enabled(X86_FEATURE_FRED)) + return; + /* We only have to do this once... */ if (likely(per_cpu(espfix_stack, cpu))) return; /* Already initialized */