From patchwork Mon Feb 26 11:07:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Roger Pau Monne X-Patchwork-Id: 13571975 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 27D06C48BF6 for ; Mon, 26 Feb 2024 11:08:28 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.685460.1066223 (Exim 4.92) (envelope-from ) id 1reYqK-00036l-8G; Mon, 26 Feb 2024 11:08:20 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 685460.1066223; Mon, 26 Feb 2024 11:08:20 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1reYqK-00036c-4L; Mon, 26 Feb 2024 11:08:20 +0000 Received: by outflank-mailman (input) for mailman id 685460; Mon, 26 Feb 2024 11:08:18 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1reYqI-00035d-UT for xen-devel@lists.xenproject.org; Mon, 26 Feb 2024 11:08:18 +0000 Received: from mail-lf1-x12f.google.com (mail-lf1-x12f.google.com [2a00:1450:4864:20::12f]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 583520df-d497-11ee-8a58-1f161083a0e0; Mon, 26 Feb 2024 12:08:18 +0100 (CET) Received: by mail-lf1-x12f.google.com with SMTP id 2adb3069b0e04-5129cdae3c6so3760009e87.1 for ; Mon, 26 Feb 2024 03:08:18 -0800 (PST) Received: from localhost ([213.195.118.74]) by smtp.gmail.com with ESMTPSA id fu38-20020a05622a5da600b0042e09c6b82dsm2307513qtb.24.2024.02.26.03.08.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 26 Feb 2024 03:08:17 -0800 (PST) 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: 583520df-d497-11ee-8a58-1f161083a0e0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=google; t=1708945697; x=1709550497; darn=lists.xenproject.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=FaG0bjtk7lVLtBaV15USC2Ji0PDyjB7kZA+T0Bke/cE=; b=GjQqKov/KDH+XwcOwCVE/7RKe2qdo3GOuUFaqPVBNajMNRN7nNnkT71ZCH722hGP85 e5B/sLGa7nGjqtlic5N3wkSNH7ISghBIwWe1vat0IUGDjA0qbAUD9Tntk2tipt6cAyuV f8gjviYzs52kHkIYmsVk5FCfjcJEyZyeYqJeE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708945697; x=1709550497; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=FaG0bjtk7lVLtBaV15USC2Ji0PDyjB7kZA+T0Bke/cE=; b=QOslzMYtuyC95td2cPoltgsqdPkzPUKnwhccYw8Y4uf/pv+jpj0lZMp5Gd/3RIG03H Ljta99vfh9lPjQguqW11XI7HuXRFI9F9a3bjkUFyOih6WEvk7x3acAN0BPF7NrvPlhy5 Obzs4YXUrd6LWXfs5QEKfNHiAxfsSeG3fq/Ra4OqENl1x7VH3ehwCbNY5Vk/aEf2cMMV 1sY6VJgO9i5q88Dj4RdRbkNH+qGfDYiqkv+w39X5ZGuWvMZ2eYorY29GhGFf5qPw0gBw 0eTOng33W47YMMSrMLkqSMnI2ngE1haXD547D+45mwW4aztdg3sPQ1c1Fblf+c+xl1E5 drhg== X-Gm-Message-State: AOJu0YzuQIOIZIFaEmbIKQ+KDp9kUC+8w5AtXmWNJXbRNqy+/fBlWG8v MgHpu0cS2Ef27jsSIbeohPhU6TcnuvPxshMZnCqEyk5K++m4JNMgA9b0P2cFbG0Qm/qc8PRUkeK z X-Google-Smtp-Source: AGHT+IFPk5TtQYJAUBadwwKI9KWtZ6T+v6n4ml3De9qHFqqBKDwnBmu3W5XhiQJ1B4vi/ShY2A3JTQ== X-Received: by 2002:ac2:4c49:0:b0:512:ec53:5915 with SMTP id o9-20020ac24c49000000b00512ec535915mr4959845lfk.15.1708945697370; Mon, 26 Feb 2024 03:08:17 -0800 (PST) From: Roger Pau Monne To: xen-devel@lists.xenproject.org Cc: Roger Pau Monne , Jan Beulich , Andrew Cooper , Wei Liu Subject: [PATCH v3 2/4] x86/spec: fix BRANCH_HARDEN option to only be set when build-enabled Date: Mon, 26 Feb 2024 12:07:46 +0100 Message-ID: <20240226110748.80254-3-roger.pau@citrix.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240226110748.80254-1-roger.pau@citrix.com> References: <20240226110748.80254-1-roger.pau@citrix.com> MIME-Version: 1.0 The current logic to handle the BRANCH_HARDEN option will report it as enabled even when build-time disabled. Fix this by only allowing the option to be set when support for it is built into Xen. Fixes: 2d6f36daa086 ('x86/nospec: Introduce CONFIG_SPECULATIVE_HARDEN_BRANCH') Signed-off-by: Roger Pau Monné Reviewed-by: Jan Beulich --- Changes since v2: - Use IS_ENABLED() in the parser. Changes since v1: - Use no_config_param(). --- xen/arch/x86/spec_ctrl.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c index 9f5ed8772533..5fae80774519 100644 --- a/xen/arch/x86/spec_ctrl.c +++ b/xen/arch/x86/spec_ctrl.c @@ -50,7 +50,8 @@ static int8_t __initdata opt_psfd = -1; int8_t __ro_after_init opt_ibpb_ctxt_switch = -1; int8_t __read_mostly opt_eager_fpu = -1; int8_t __read_mostly opt_l1d_flush = -1; -static bool __initdata opt_branch_harden = true; +static bool __initdata opt_branch_harden = + IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_BRANCH); bool __initdata bsp_delay_spec_ctrl; uint8_t __read_mostly default_xen_spec_ctrl; @@ -268,7 +269,16 @@ static int __init cf_check parse_spec_ctrl(const char *s) else if ( (val = parse_boolean("l1d-flush", s, ss)) >= 0 ) opt_l1d_flush = val; else if ( (val = parse_boolean("branch-harden", s, ss)) >= 0 ) - opt_branch_harden = val; + { + if ( IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_BRANCH) ) + opt_branch_harden = val; + else + { + no_config_param("SPECULATIVE_HARDEN_BRANCH", "spec-ctrl", s, + ss); + rc = -EINVAL; + } + } else if ( (val = parse_boolean("srb-lock", s, ss)) >= 0 ) opt_srb_lock = val; else if ( (val = parse_boolean("unpriv-mmio", s, ss)) >= 0 )