Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751293AbcCFGUS (ORCPT ); Sun, 6 Mar 2016 01:20:18 -0500 Received: from mail-qg0-f49.google.com ([209.85.192.49]:36387 "EHLO mail-qg0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751151AbcCFGUR (ORCPT ); Sun, 6 Mar 2016 01:20:17 -0500 Date: Sun, 6 Mar 2016 13:20:13 +0700 (ICT) From: Nicolas Pitre To: Michal Marek cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 5/8] kbuild: add fine grained build dependencies for exported symbols In-Reply-To: Message-ID: References: <1457070050-1564-1-git-send-email-nicolas.pitre@linaro.org> <1457070050-1564-6-git-send-email-nicolas.pitre@linaro.org> <56DA118E.20106@suse.com> <56DA1201.9010605@suse.cz> <20160305071208.GA25757@pobox.suse.cz> User-Agent: Alpine 2.20 (LFD 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2953 Lines: 59 On Sat, 5 Mar 2016, Nicolas Pitre wrote: > On Sat, 5 Mar 2016, Michal Marek wrote: > > > I reproduced the SIGBUS after a few iterations, and it crashes in > > parse_dep_file(). I'm now testing this > > > > diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include > > index 0be7e09ba381..4fdd8348acf6 100644 > > --- a/scripts/Kbuild.include > > +++ b/scripts/Kbuild.include > > @@ -270,10 +270,12 @@ else > > > > # Filter out exported kernel symbol names from the preprocessor output. > > # See also __KSYM_DEPS__ in include/linux/export.h. > > +# We disable the depfile generation here, so as not to overwrite the existing > > +# depfile while fixdep is parsing it > > ksym_dep_filter = \ > > case "$(1)" in \ > > - cc_*_c) $(CPP) $(c_flags) -D__KSYM_DEPS__ $< ;; \ > > - as_*_S) $(CPP) $(a_flags) -D__KSYM_DEPS__ $< ;; \ > > + cc_*_c) $(CPP) $(filter-out -Wp$(comma)-M%, $(c_flags)) -D__KSYM_DEPS__ $< ;; \ > > + as_*_S) $(CPP) $(filter-out -Wp$(comma)-M%, $(a_flags)) -D__KSYM_DEPS__ $< ;; \ > > cpp_lds_S) : ;; \ > > *) echo "Don't know how to preprocess $(1)"; false ;; \ > > esac | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p' > > This makes perfect sense even if I can't reproduce on my side. I folded the following patch into my tree and pushed it out. diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 0be7e09ba3..2c14a27e39 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -270,14 +270,17 @@ else # Filter out exported kernel symbol names from the preprocessor output. # See also __KSYM_DEPS__ in include/linux/export.h. +# We disable the depfile generation here, so as not to overwrite the existing +# depfile while fixdep is parsing it +flags_nodeps = $(filter-out -Wp$(comma)-M%, $($(1))) ksym_dep_filter = \ case "$(1)" in \ - cc_*_c) $(CPP) $(c_flags) -D__KSYM_DEPS__ $< ;; \ - as_*_S) $(CPP) $(a_flags) -D__KSYM_DEPS__ $< ;; \ + cc_*_c) $(CPP) $(call flags_nodeps,c_flags) -D__KSYM_DEPS__ $< ;; \ + as_*_S) $(CPP) $(call flags_nodeps,a_flags) -D__KSYM_DEPS__ $< ;; \ cpp_lds_S) : ;; \ - *) echo "Don't know how to preprocess $(1)"; false ;; \ + *) echo "Don't know how to preprocess $(1)" >&2; false ;; \ esac | sed -rn 's/^.*=== __KSYM_(.*) ===.*$$/KSYM_\1/p' - + cmd_and_fixdep = \ $(echo-cmd) $(cmd_$(1)); \ $(ksym_dep_filter) | \ Nicolas