From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2512C433F5 for ; Wed, 5 Oct 2022 11:34:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230071AbiJELeE (ORCPT ); Wed, 5 Oct 2022 07:34:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229980AbiJELdh (ORCPT ); Wed, 5 Oct 2022 07:33:37 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D22574377; Wed, 5 Oct 2022 04:33:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7831E61645; Wed, 5 Oct 2022 11:33:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 832A2C433B5; Wed, 5 Oct 2022 11:33:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1664969603; bh=f1rxL/ZU4hrwCN+ID9VPHxiCs0f7piVCOV+3m7m4f8Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=veJq4rzwxmAsAiY+O326SUk8gpeLIr8Kt3C9BLf9+1npIClVVRMHhhcnM/BguV7TH KWBrX1GutPp2UvEId3IFr71nreU/b+zRiHeVny7NOeiBC1hZFLUqSms07oEoW/vkHB 1qXoyOIELpmNFl3xT+2teB6+OQ/m8VF+1rq7/XIs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Josh Poimboeuf , "Peter Zijlstra (Intel)" , Borislav Petkov , Thadeu Lima de Souza Cascardo Subject: [PATCH 5.4 21/51] x86/speculation: Fix SPEC_CTRL write on SMT state change Date: Wed, 5 Oct 2022 13:32:09 +0200 Message-Id: <20221005113211.251461820@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221005113210.255710920@linuxfoundation.org> References: <20221005113210.255710920@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josh Poimboeuf commit 56aa4d221f1ee2c3a49b45b800778ec6e0ab73c5 upstream. If the SMT state changes, SSBD might get accidentally disabled. Fix that. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/bugs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1335,7 +1335,8 @@ static void __init spectre_v2_select_mit static void update_stibp_msr(void * __unused) { - write_spec_ctrl_current(x86_spec_ctrl_base, true); + u64 val = spec_ctrl_current() | (x86_spec_ctrl_base & SPEC_CTRL_STIBP); + write_spec_ctrl_current(val, true); } /* Update x86_spec_ctrl_base in case SMT state changed. */