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 A7DE8C433F5 for ; Thu, 24 Feb 2022 15:18:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236086AbiBXPT1 (ORCPT ); Thu, 24 Feb 2022 10:19:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235978AbiBXPSa (ORCPT ); Thu, 24 Feb 2022 10:18:30 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C698144F50 for ; Thu, 24 Feb 2022 07:17:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=JWR1Jvatd2wRq94EgF2FFUHDrJsSm4yXOI7jdL4Xcs4=; b=h4QDH/Gv96wd3eVPV61DyLB68+ t8jRD2oT1kQAdAHgy8Mztir6XZCLuZIBG1ZLpDhzAR8ObMy5QP37KpXMmCLOktSFSGuoQGy3KTuE2 9vclMYuuBtMTYxgUzgpGUIOQsR4rihCZYupCrzIepI4xIyBMVZVPGpCvgAAWRyPnKY72I5wQhA4rg PoQtrnuKUjPiUyXWDRJhvckIB00KSpRdvjuigiqn40+WItp9iXmwSVnA3TUvVq4LR+eQqdWooBbHr yxTn6Gjxco/LIoO+EhR1tnLB3yaoDkR3yozmHQGmTzxU6ciIA+DJtngIeKyni4l9pHCo7JIUY8Yzw gPSyE2ZA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nNFs4-004s2N-Du; Thu, 24 Feb 2022 15:17:32 +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 5339B302DB9; Thu, 24 Feb 2022 16:17:29 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id B7E842B3547B3; Thu, 24 Feb 2022 16:17:28 +0100 (CET) Message-ID: <20220224151324.256729197@infradead.org> User-Agent: quilt/0.66 Date: Thu, 24 Feb 2022 15:52:16 +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, mbenes@suse.cz, rostedt@goodmis.org, mhiramat@kernel.org, alexei.starovoitov@gmail.com Subject: [PATCH v2 38/39] x86/ibt: Ensure module init/exit points have references References: <20220224145138.952963315@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_KERNEL_IBT + +#define __CFI_ADDRESSABLE(fn, __attr) \ + const void *__cfi_jt_ ## fn __visible __attr = (void *)&fn + +#endif /* CONFIG_X86_KERNEL_IBT */ #endif /* CONFIG_CFI_CLANG */ +#ifndef __CFI_ADDRESSABLE +#define __CFI_ADDRESSABLE(fn, __attr) +#endif + #endif /* _LINUX_CFI_H */