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=-14.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 4310CC433E0 for ; Wed, 24 Jun 2020 20:59:29 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 978902075A for ; Wed, 24 Jun 2020 20:59:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pd1+e0uX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 978902075A 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-19133-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 7784 invoked by uid 550); 24 Jun 2020 20:59:23 -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 7751 invoked from network); 24 Jun 2020 20:59:22 -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=zWM/30Wl1IsQgoPaDiN0rPEEBtrHBKt/BJnnp0eLWds=; b=pd1+e0uXRIvGNNQgZ7G0+2YkwsDFhSclmocO1GbaT5UM3c6xBTX7UYJjCsai0aiyT7 fIoijSJoU+eUl8voyiO0IOyBsavQt6eREqkk3whDlDlHejxDQRKECAFiVGUe/CKDHaTc EpZ2md8ULTkAVVBJ6O72PRwIcg/GiVClV1rha8JNSiYzT4/v2ecYsi++FLxwW19Hw/Gd Fr/Z+ikfp69sRAivcJnbajJT1/5/Qn2W6vWHskjofe5p2ZJr6Cthm+UKTVG2rZslsDkG xO7mHbrOSScz4BsI8HgHuMYhqH42CQPx5Ip80xrwiQdph3TwAg+m578XBSL3rfWRIGQZ ATEA== 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=zWM/30Wl1IsQgoPaDiN0rPEEBtrHBKt/BJnnp0eLWds=; b=JchTap1XavjBkGNvssT8oJ1zH539xwi20cYs3MNL0Ku99bx/gU9/bIjhsjuSDObZY6 3SsUTQwAMVv2m/hBVxXk1Jpk89as/XGAYFQzilpRorBEyCsvIORWgPLGUt/kfiq6vgi9 BZm9P8Dr3LQkmzRp6ddrxgkqHpJKyKBvLiX1tv8TyP0qSRm6pip1dmaJVk0k6x991xJD G2xkJ5I7nrv1o1yVTTYsLZ18COi6na+msITrPNbq/pbz4fGh6/YoYNoLAlMxbZKJ4COA R2sTohPa3/fzFinLtzY4Cjhls0lqan6Tjw2K002/pWF5oX0uQ4ZE5HZfoYCy7rcoPft+ s7oA== X-Gm-Message-State: AOAM530S8ibu6uhNSE4gczMu+HAozCL/xy/1n9yeYDYggZndbeVO45N0 JmAP5tEu87C8s2sEs9EXV9yuiqPeU3AurvzVaE5U8w== X-Google-Smtp-Source: ABdhPJxCHHL5VXpLPing5E72KwPslmx5t7evOEk09T9ji09mKT6bSRCDPTi/AxhdrzEhszh9gGm6vbYGZSEoMtti7/U= X-Received: by 2002:a17:90a:21ef:: with SMTP id q102mr5252324pjc.101.1593032350091; Wed, 24 Jun 2020 13:59:10 -0700 (PDT) MIME-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> <20200624203200.78870-18-samitolvanen@google.com> In-Reply-To: <20200624203200.78870-18-samitolvanen@google.com> From: Nick Desaulniers Date: Wed, 24 Jun 2020 13:58:57 -0700 Message-ID: Subject: Re: [PATCH 17/22] arm64: vdso: disable LTO To: Sami Tolvanen Cc: Masahiro Yamada , Will Deacon , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , clang-built-linux , Kernel Hardening , linux-arch , Linux ARM , Linux Kbuild mailing list , LKML , linux-pci@vger.kernel.org, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" Content-Type: text/plain; charset="UTF-8" On Wed, Jun 24, 2020 at 1:33 PM Sami Tolvanen wrote: > > Filter out CC_FLAGS_LTO for the vDSO. Just curious about this patch (and the following one for x86's vdso), do you happen to recall specifically what the issues with the vdso's are? > > Signed-off-by: Sami Tolvanen > --- > arch/arm64/kernel/vdso/Makefile | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile > index 556d424c6f52..cfad4c296ca1 100644 > --- a/arch/arm64/kernel/vdso/Makefile > +++ b/arch/arm64/kernel/vdso/Makefile > @@ -29,8 +29,8 @@ ldflags-y := -shared -nostdlib -soname=linux-vdso.so.1 --hash-style=sysv \ > ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 > ccflags-y += -DDISABLE_BRANCH_PROFILING > > -CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) > -KBUILD_CFLAGS += $(DISABLE_LTO) > +CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \ > + $(CC_FLAGS_LTO) > KASAN_SANITIZE := n > UBSAN_SANITIZE := n > OBJECT_FILES_NON_STANDARD := y > -- > 2.27.0.212.ge8ba1cc988-goog > -- Thanks, ~Nick Desaulniers