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 4CB66C27C40 for ; Thu, 24 Aug 2023 17:22:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242687AbjHXRVn (ORCPT ); Thu, 24 Aug 2023 13:21:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242823AbjHXRVP (ORCPT ); Thu, 24 Aug 2023 13:21:15 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6C56219B5 for ; Thu, 24 Aug 2023 10:21:13 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 025CA67100 for ; Thu, 24 Aug 2023 17:21:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 01C9EC433C8; Thu, 24 Aug 2023 17:21:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1692897672; bh=0k43O3RQooUb3RGKiZKllc8RU5F+rBjMQ1G6kOAnL1Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ij0RvTpfkkDt1fYgJEuZhoGhs32IynSouUuB4YdjAjrv6XR3n6xv/MWj9B6eR4IGr vT7G/WHrHWlXuoZ54Syt/xjMKmjq34ddv11/cmy9SI9X2L7aWtsTvQ6tJim6BW2+9R rP7HdlgLsvu2MR36/hTGVtyNrxVoH0e9UrTPiqfg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Peter Zijlstra (Intel)" , "Borislav Petkov (AMD)" , Sasha Levin Subject: [PATCH 5.10 120/135] x86/cpu: Fix up srso_safe_ret() and __x86_return_thunk() Date: Thu, 24 Aug 2023 19:09:52 +0200 Message-ID: <20230824170622.474621805@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230824170617.074557800@linuxfoundation.org> References: <20230824170617.074557800@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Zijlstra commit af023ef335f13c8b579298fc432daeef609a9e60 upstream. vmlinux.o: warning: objtool: srso_untrain_ret() falls through to next function __x86_return_skl() vmlinux.o: warning: objtool: __x86_return_thunk() falls through to next function __x86_return_skl() This is because these functions (can) end with CALL, which objtool does not consider a terminating instruction. Therefore, replace the INT3 instruction (which is a non-fatal trap) with UD2 (which is a fatal-trap). This indicates execution will not continue past this point. Fixes: fb3bd914b3ec ("x86/srso: Add a Speculative RAS Overflow mitigation") Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20230814121148.637802730@infradead.org Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/x86/lib/retpoline.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -199,7 +199,7 @@ SYM_INNER_LABEL(srso_safe_ret, SYM_L_GLO int3 lfence call srso_safe_ret - int3 + ud2 SYM_CODE_END(srso_safe_ret) SYM_FUNC_END(srso_untrain_ret) __EXPORT_THUNK(srso_untrain_ret) @@ -209,7 +209,7 @@ SYM_CODE_START(__x86_return_thunk) ANNOTATE_NOENDBR ALTERNATIVE_2 "jmp __ret", "call srso_safe_ret", X86_FEATURE_SRSO, \ "call srso_safe_ret_alias", X86_FEATURE_SRSO_ALIAS - int3 + ud2 SYM_CODE_END(__x86_return_thunk) EXPORT_SYMBOL(__x86_return_thunk)