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 X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65B3EC2BA83 for ; Wed, 12 Feb 2020 17:36:53 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id B36DA2073C for ; Wed, 12 Feb 2020 17:36:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="WTUFnbqw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B36DA2073C Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17797-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 1231 invoked by uid 550); 12 Feb 2020 17:36:47 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 1209 invoked from network); 12 Feb 2020 17:36:46 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=oXC2J3nEK5SwOdFoK4ULqW0570rBTdySIYo3+gIlo9M=; b=WTUFnbqwYf+rL57s/FGxM1+vxE9Jz5IK7E+OqB1D8Yag+QT+LdUeuoco6oTC4zgy7L TKipBuXtB2O8hn6XUjmdUpdrUfke0F8SCdmbLI53UNP2BplyGiw6vXFuWmFYFzZtLQeN 5wpar/5ILukP9S05BShLrDSCKEPCKcsSH/oAGyElM1PsKMhn2zidyE008XJx5PD7dUMg n4j6E1083epW+BkViMtDeuVftqlXVyhEyjY2m1kZGGBAfrXmhWXYSRy7y6cbm8taKOCJ y3l8mKYES7s2h2SOYn+hKiFfdkCBn2+SUUTjhfBmJGbvU+drkZVcb4Ou3zqNKzp4BpKd nG4Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oXC2J3nEK5SwOdFoK4ULqW0570rBTdySIYo3+gIlo9M=; b=lIzdDJzSqZTqmAQ7Z5bbEJXbEfYgsS+C8y9NMFFvqHahvprYQkL7FqaccjZ2/GwAKS h1yKV6JVsfQncGCEoQnpU5J0UuSKhVrSQyXpCqUX8hfSRgfESDCC1fRpmSAW1V4zvbe4 Nj0MChOhtxu38MHUBEmK7Wq8F8NFCm6DQOqQczFrRn9MEJ9YenIHLMgqxuMv2i9eyptU C2FM2bTethp9YEWoziLHSKID4CFQfPbhc3iGpd++Y27d5aGcYW8gUHTOam1UR1I4NGpr XKRIrF1Qabhfb+jjEjLUAw/K+udO5D+KPjEdF4AUsT7jn1PNNlOLANxH63MIL5+muGmy ZISw== X-Gm-Message-State: APjAAAV0L2hF8NHqhTAEjfNE5pZ5vflglg+sB8QqqprbZHz2C10A3ztB VmhrS2OKMnAn5r/3a2qQ1mW13Jr51/fUeeWnrTdsjw== X-Google-Smtp-Source: APXvYqySnCPpjBgnelV684/U07lYpWTQs3A+aOrC5t4BnyXhAn03wUz7JH8o/EDUYvzcfRllMDnDJ3B306fqXtaeZDQ= X-Received: by 2002:ab0:422:: with SMTP id 31mr5283734uav.98.1581528994562; Wed, 12 Feb 2020 09:36:34 -0800 (PST) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20200128184934.77625-1-samitolvanen@google.com> <63517cff-4bd6-bb6c-9a54-23de4f5fbb4a@arm.com> In-Reply-To: <63517cff-4bd6-bb6c-9a54-23de4f5fbb4a@arm.com> From: Sami Tolvanen Date: Wed, 12 Feb 2020 09:36:23 -0800 Message-ID: Subject: Re: [PATCH v7 00/11] add support for Clang's Shadow Call Stack To: James Morse Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland , Dave Martin , Kees Cook , Laura Abbott , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux , Kernel Hardening , linux-arm-kernel , LKML Content-Type: text/plain; charset="UTF-8" On Tue, Feb 11, 2020 at 5:57 AM James Morse wrote: > I found I had to add: > | KBUILD_CFLAGS := $(filter-out -ffixed-x18 $(CC_FLAGS_SCS), $(KBUILD_CFLAGS)) > > to drivers/firmware/efi/libstub/Makefile, to get this going. Ah, good catch! > I don't think there is much point supporting SCS for the EFIstub, its already isolated > from the rest of the kernel's C code by the __efistub symbol prefix machinery, and trying > to use it would expose us to buggy firmware at a point we can't handle it! Yes, fully agreed. > I can send a patch if its easier for you, It's not a problem, I will include a patch for this in v8. Sami