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=-14.4 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=ham 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 10EB3C4CEC4 for ; Mon, 23 Sep 2019 17:25:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6EDB20820 for ; Mon, 23 Sep 2019 17:25:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="i8rP3w8H" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407427AbfIWRZe (ORCPT ); Mon, 23 Sep 2019 13:25:34 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:39231 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389167AbfIWRZe (ORCPT ); Mon, 23 Sep 2019 13:25:34 -0400 Received: by mail-pf1-f193.google.com with SMTP id v4so4905525pff.6 for ; Mon, 23 Sep 2019 10:25:34 -0700 (PDT) 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=L3+53+4tDqcisH8nEn571hrd9nXBXU/wwqjTnECUQJw=; b=i8rP3w8H7XdRZzQC+vEtNbIOw2PeTLnH4pc4n+PfWkBuD6VjnLKHotKRieESI8WjSm JjZwAvWJhfKceU+qeK6fooGbCYweulh8jCh64Yz5EGZ1jzK8AozeErEi4H3XF4eEXBPh uCGqhTWoQMKGi9U0WOrIXVYcs5bNWMxlrTVs/He24GaBoNyTc9mSMmH/4A175a3IaX27 Ib0jnP4AFA6g/nkI2nu+ZO9C5qjYMZOKSD3G0da4lcjdVTa17aGrH1lzHRqH02mAkVI1 4ghF493+SAr863MhjVdpGXL2IhkO1ycALDeTCLWCb6jUt1cW3S1jINQnz14FGfI3EvZ7 0g+A== 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=L3+53+4tDqcisH8nEn571hrd9nXBXU/wwqjTnECUQJw=; b=Ii/1yiFttzD1HUM8Ry+C2+56qQawOb0dvsmvNaJG99P9m8DzNI2rBYoa07l0f6YqNs HpbHnZPqkHIRWezOwWp6+jErg6hxQ7RIrJa2xRsLrQ2Gr9jzPxzP64TqcRNNGETG21fu ilXwVLxgVFDcpN8xuhg16r9y/kFnPwAIO4JoNgnP8cX41XSVLtPl5EMlfJs9EIFZq4K7 ObcTRK9bzFEEihToxlfxvM2ABcJaMWe0FCwijK/dzXLkIv0v4KM5ZYhwZ+dvnfo+h3LL FMYjVByN6LIZ4CxofTc7idPOxPPu+ct9HGfwkmkIbBvqMLljfWgD2PJUbSkYd6cDcvEq WXtw== X-Gm-Message-State: APjAAAUnDFnyJdSyRbnkJwICbfBJa2ogQlB5O4mV6Fxzl05tHPAC9YfU FLGb/XR/klmWoDK64CPpD3ymGibhdjzS05ZNWWy9sw== X-Google-Smtp-Source: APXvYqzPebvl4GooiI4/1Ommn9k5fln0V+QYnrzWrMivCXE4C96/PAtt1lM1qELnrjqrWt506wH4mQ/oJ0m2QGgjYtA= X-Received: by 2002:a17:90a:154f:: with SMTP id y15mr597914pja.73.1569259533361; Mon, 23 Sep 2019 10:25:33 -0700 (PDT) MIME-Version: 1.0 References: <20190922173241.GA44503@rani.riverdale.lan> <20190923171753.GA2252517@rani.riverdale.lan> In-Reply-To: <20190923171753.GA2252517@rani.riverdale.lan> From: Nick Desaulniers Date: Mon, 23 Sep 2019 10:25:22 -0700 Message-ID: Subject: Re: [PATCH] x86/purgatory: Add $(DISABLE_STACKLEAK_PLUGIN) To: Arvind Sankar Cc: LKML , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Ard Biesheuvel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 23, 2019 at 10:17 AM Arvind Sankar wrote: > > Since commit b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than > reset KBUILD_CFLAGS") kexec breaks is GCC_PLUGIN_STACKLEAK is enabled, as > the purgatory contains undefined references to stackleak_track_stack. > Attempting to load a kexec kernel results in: > kexec: Undefined symbol: stackleak_track_stack > kexec-bzImage64: Loading purgatory failed > > Fix this by disabling the stackleak plugin for purgatory. > > Fixes: b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than reset KBUILD_CFLAGS") > Signed-off-by: Arvind Sankar Reviewed-by: Nick Desaulniers (Sorry for the fallout from b059f801a937, but this is giving us a pretty good idea about what "runtime" requirements certain configs have. It would be cool to eventually have some kind of kexec test case that folks could run in QEMU). > --- > arch/x86/purgatory/Makefile | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile > index 527749066d31..fb4ee5444379 100644 > --- a/arch/x86/purgatory/Makefile > +++ b/arch/x86/purgatory/Makefile > @@ -25,6 +25,7 @@ KCOV_INSTRUMENT := n > > PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel > PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss > +PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) > > # Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That > # in turn leaves some undefined symbols like __fentry__ in purgatory and not > -- > 2.21.0 > -- Thanks, ~Nick Desaulniers