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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 16FBCC43461 for ; Thu, 3 Sep 2020 22:46:31 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 54E5820716 for ; Thu, 3 Sep 2020 22:46:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="oZ5KzCEi" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54E5820716 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19774-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 17470 invoked by uid 550); 3 Sep 2020 22:46:23 -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 17438 invoked from network); 3 Sep 2020 22:46:22 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=5TqmD5EyVPuB9TiyITqacSmLzI3cDbmlqWUeyi+ujCg=; b=oZ5KzCEi7wKIrEEj86amUMkUmItIM2KtyMb6kJV1Bx2j+6SLbFuob0rHAOq9f5nYH0 BvcS2/vu4CZRFtoI7y0Mt062eAYVzZTqZzFG2Iu7rRRlhQSIXmNmKgue9t4cr4gsNbj6 cT+JilU0DZpxA7uH2zokAyWWmg9TpkmIfF0Qk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=5TqmD5EyVPuB9TiyITqacSmLzI3cDbmlqWUeyi+ujCg=; b=KCMqcT/tg+a3MhD2ujCifDJzOEbdKde1koqLcFVSZbvdk8zZ0brkM/DbzAWKpXlZIe d476amiul0XDKhFe3kfplaSXAbZC+CB+FOONwHuxTToatnOQjFdAMkVKHd5a2vU8nk27 5fQq/hjaLlJQNecm/O2R7uuWLg1DvQAUO4jxXVHv1rHWlkEYOeAKhqDr1XyEYCVAvGvM lHIkJ5CK+tLvAJJXI95Cs65O6h3g42tVdTCim8ExpBaU/Pn/P9D3/o7DgsXaWsQK431n 2WghjSEEkkAGw1MvjlogFxNMWhvoIKkxSA/a//0kSluAw5PVgHhxY0kj66ejHYIIgc1+ Hyew== X-Gm-Message-State: AOAM530dOsBiKbFn+Pxe/4VCNTeu401xkprRjcnEgHo5MteKQ+PBmqb7 NpHw5qXSB9JBCXXdZzlX+FLcUg== X-Google-Smtp-Source: ABdhPJz0Cu4W/SGUiAG+2DPCBbmeCYnLc7352WExRrDx24NF8XVfzJeuLOmeQkS8ntOwly5Q8T3lkw== X-Received: by 2002:a63:ca12:: with SMTP id n18mr4721941pgi.371.1599173171199; Thu, 03 Sep 2020 15:46:11 -0700 (PDT) Date: Thu, 3 Sep 2020 15:46:09 -0700 From: Kees Cook To: Sami Tolvanen Cc: Masahiro Yamada , Will Deacon , Peter Zijlstra , Steven Rostedt , Greg Kroah-Hartman , "Paul E. McKenney" , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v2 26/28] x86, vdso: disable LTO only for vDSO Message-ID: <202009031546.98CA2EF4@keescook> References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> <20200903203053.3411268-27-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200903203053.3411268-27-samitolvanen@google.com> On Thu, Sep 03, 2020 at 01:30:51PM -0700, Sami Tolvanen wrote: > Remove the undefined DISABLE_LTO flag from the vDSO, and filter out > CC_FLAGS_LTO flags instead where needed. Note that while we could use > Clang's LTO for the 64-bit vDSO, it won't add noticeable benefit for > the small amount of C code. > > Signed-off-by: Sami Tolvanen Moar DISABLE_LTO... Reviewed-by: Kees Cook -- Kees Cook