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 A8894C43334 for ; Tue, 26 Jul 2022 00:10:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231995AbiGZAKh (ORCPT ); Mon, 25 Jul 2022 20:10:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231396AbiGZAKg (ORCPT ); Mon, 25 Jul 2022 20:10:36 -0400 Received: from mail-yb1-xb35.google.com (mail-yb1-xb35.google.com [IPv6:2607:f8b0:4864:20::b35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BDCD11FCC0 for ; Mon, 25 Jul 2022 17:10:34 -0700 (PDT) Received: by mail-yb1-xb35.google.com with SMTP id d124so5386412ybb.5 for ; Mon, 25 Jul 2022 17:10:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=2jEuccm+13frSO13F4UbCDTaTKUna0j27ZhD3kYwCOE=; b=JG1XFgHmFM4OuFOHTn6dJ+pnT7DBjuTnLLajlNshh/FVuAMf/Vcgwwn8szGEZ8KruF vQpvV4fPl3wu0AFGuxR+056dIMgw+zWIjX+TffF1DhBaJaFOpdAzRIYDtTKCvoAKjdXj BzVxedIfh40R8VC6K5GWDkdtNRHXbf4k18N/yLNjoKQr4hzcCeJg2x+w1GqNya2gnj8o FfyymnsCfk/iOTTbIXvP24Vt9k2ZpvlqeM2z9LgEMTllqAJj6kzzaqUVsrhi57Yt/BRw x+1HgIa1RKXKE4fimavD8OUII7AuSQOc4PYz6QCzHTzBlw7Phkl4GzrXs0dMWoCEs+LM hZXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=2jEuccm+13frSO13F4UbCDTaTKUna0j27ZhD3kYwCOE=; b=tgyYZTBcoKjOvUwna1z7UUwt2+DCZpxDJd4e5jd2zZNP+qAAcwLmWBAAxn0jQf9HB/ Iv1HXqGCsqcaAwhDt0qWMLRz55eqVXT+R+vNvK9mCJbNgH+Q8UHlTNt4xb0VabZoBogZ R5Bh3Q4ngZpXZE92s6Wf3Dpfs+ACShI69qijGUJJmGaubY7UFaWGLZGWOYqFnn/LsAke odQ/826ubPQV2QPDOXi9uXVhyt6kMT4dV4jZgxtikcDbamosGiOgbMQLjEJqi/j4dPlt JH/9xfKvqSROvtwgidLUVkJUW5PJmDC9D1qe0IpbLPEkANWR86RPyoArg18c8qDhpvvb HbQA== X-Gm-Message-State: AJIora9wxYJnnHSHDFQt9Bh2WSUFYq0IrJ4AwrU9foJXWvKYRnhI5Jyk r7J2IWgIPYRSbBJCoqmR1pMeOae38WWS+k9q1DOyTg== X-Google-Smtp-Source: AGRyM1vcor1AoZoF/hJYr87qRlJIfLAt0f7iGROesAM925P5MkdFlgqOJv1cHjTmmUDBGaoOCe+/7SUZgR29WPcH5Y0= X-Received: by 2002:a5b:cc6:0:b0:66e:45c6:2a25 with SMTP id e6-20020a5b0cc6000000b0066e45c62a25mr11454535ybr.304.1658794233835; Mon, 25 Jul 2022 17:10:33 -0700 (PDT) MIME-Version: 1.0 References: <20220610233513.1798771-1-samitolvanen@google.com> <20220610233513.1798771-21-samitolvanen@google.com> In-Reply-To: From: Sami Tolvanen Date: Mon, 25 Jul 2022 17:09:57 -0700 Message-ID: Subject: Re: [RFC PATCH v3 20/20] x86: Add support for CONFIG_CFI_CLANG To: Peter Zijlstra Cc: LKML , Kees Cook , Josh Poimboeuf , X86 ML , Catalin Marinas , Will Deacon , Mark Rutland , Nathan Chancellor , Nick Desaulniers , Joao Moreira , Sedat Dilek , Steven Rostedt , linux-hardening@vger.kernel.org, linux-arm-kernel , llvm@lists.linux.dev Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jul 23, 2022 at 4:21 AM Peter Zijlstra wrote: > > On Fri, Jun 10, 2022 at 04:35:13PM -0700, Sami Tolvanen wrote: > > > +#ifdef CONFIG_CFI_CLANG > > +#define __CFI_TYPE(name) \ > > + .fill 7, 1, 0xCC ASM_NL \ > > + SYM_START(__cfi_##name, SYM_L_LOCAL, SYM_A_NONE) \ > > + int3 ASM_NL \ > > + int3 ASM_NL \ > > + mov __kcfi_typeid_##name, %eax ASM_NL \ > > + int3 ASM_NL \ > > + int3 ASM_NL \ > > + SYM_FUNC_END(__cfi_##name) > > +#endif > > Like said on IRC yesterday, this doesn't generate the right mov > encoding. > > .byte 0xb8 ; .long __kcfi_typeid_##name ; \ > > works. Your LLVM tree already has the ZExt patch you gave me yesterday > to fix up the linker fallout from this change. Indeed, I updated my kernel tree and confirmed that this fixes the issue. Thanks for pointing it out. Sami