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 94322C433F5 for ; Fri, 18 Feb 2022 17:15:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238287AbiBRRPg (ORCPT ); Fri, 18 Feb 2022 12:15:36 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:43214 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238208AbiBRRPP (ORCPT ); Fri, 18 Feb 2022 12:15:15 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 210AF4C797 for ; Fri, 18 Feb 2022 09:14:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=iWCaY7NI/L/iDc9xkcz41iMOxuIJlwmQcyXvI6kFQmg=; b=bmkGxUWZBkx4CSDAUBH5mmvYfq YFHzvM3YPbdSOgRXE8OMZk1Fd5GYpMpt4HzV/9pZcXmtO3BAob1VDEvBBnGB4KApwiCtzbSz8CM96 3ZuKLpu8+yqRWQ5/1JYWev7djJtgRJJmhqRPnhQHrxtTguJmbK29IxPUfG15kwcPGBTiGmQIdZU37 aSliHQOmQzvGg9lh6iADjj5CkgJFH/RNeelQ4ByQKrVPy50uhPSQCEDnw/zXQHiPwFFV3jjgQz9pP x5kIU/9ogUI1ue+JxBA2qWc8L0Z+Nfpmbnn3sooHoRwVBL5pD977XAvzJHykHgHgxpb5INeRDFpab W7DC2vBA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nL6qB-00AsBm-14; Fri, 18 Feb 2022 17:14:43 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D8759302D39; Fri, 18 Feb 2022 18:14:39 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 78FAC2B09FA74; Fri, 18 Feb 2022 18:14:39 +0100 (CET) Message-ID: <20220218171410.239673712@infradead.org> User-Agent: quilt/0.66 Date: Fri, 18 Feb 2022 17:49:30 +0100 From: Peter Zijlstra To: x86@kernel.org, joao@overdrivepizza.com, hjl.tools@gmail.com, jpoimboe@redhat.com, andrew.cooper3@citrix.com Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, ndesaulniers@google.com, keescook@chromium.org, samitolvanen@google.com, mark.rutland@arm.com, alyssa.milburn@intel.com Subject: [PATCH 28/29] x86/ibt: Ensure module init/exit points have references References: <20220218164902.008644515@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since the references to the module init/exit points only have external references, a module LTO run will consider them 'unused' and seal them, leading to an immediate fail on module load. Signed-off-by: Peter Zijlstra (Intel) --- include/linux/cfi.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) --- a/include/linux/cfi.h +++ b/include/linux/cfi.h @@ -34,8 +34,17 @@ static inline void cfi_module_remove(str #else /* !CONFIG_CFI_CLANG */ -#define __CFI_ADDRESSABLE(fn, __attr) +#ifdef CONFIG_X86_IBT + +#define __CFI_ADDRESSABLE(fn, __attr) \ + const void *__cfi_jt_ ## fn __visible __attr = (void *)&fn + +#endif /* CONFIG_X86_IBT */ #endif /* CONFIG_CFI_CLANG */ +#ifndef __CFI_ADDRESSABLE +#define __CFI_ADDRESSABLE(fn, __attr) +#endif + #endif /* _LINUX_CFI_H */