From 54b880caf15034644b564e378abf67b7f9eaf4dc Mon Sep 17 00:00:00 2001 From: James Hogan Date: Fri, 24 Jun 2016 23:42:23 +0100 Subject: [PATCH 1/2] kbuild, x86: Track generated headers with generated-y Track generated header files which aren't already in genhdr-y, alongside generic-y wrappers in the */include/generated/[uapi/]asm/ directories. Currently only x86 generates extra headers in these directories, for the purposes of enumerating system calls for different ABIs, and xen hypercalls. This will allow the asm-generic wrapper handling code to remove stale wrappers when files are removed from generic-y, without also removing these headers which are generated separately. Reported-by: kbuild test robot Signed-off-by: James Hogan Acked-by: Arnd Bergmann Cc: Jonathan Corbet Cc: linux-kbuild@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: Michal Marek Link: http://lkml.kernel.org/r/1466808144-23209-2-git-send-email-james.hogan@imgtec.com Signed-off-by: Thomas Gleixner --- Documentation/kbuild/makefiles.txt | 14 ++++++++++++++ arch/x86/include/asm/Kbuild | 6 ++++++ 2 files changed, 20 insertions(+) diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 13f888a02a3d..385a5ef41c17 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -47,6 +47,7 @@ This document describes the Linux kernel Makefiles. --- 7.2 genhdr-y --- 7.3 destination-y --- 7.4 generic-y + --- 7.5 generated-y === 8 Kbuild Variables === 9 Makefile language @@ -1319,6 +1320,19 @@ See subsequent chapter for the syntax of the Kbuild file. Example: termios.h #include + --- 7.5 generated-y + + If an architecture generates other header files alongside generic-y + wrappers, and not included in genhdr-y, then generated-y specifies + them. + + This prevents them being treated as stale asm-generic wrappers and + removed. + + Example: + #arch/x86/include/asm/Kbuild + generated-y += syscalls_32.h + === 8 Kbuild Variables The top Makefile exports the following variables: diff --git a/arch/x86/include/asm/Kbuild b/arch/x86/include/asm/Kbuild index aeac434c9feb..2cfed174e3c9 100644 --- a/arch/x86/include/asm/Kbuild +++ b/arch/x86/include/asm/Kbuild @@ -1,5 +1,11 @@ +generated-y += syscalls_32.h +generated-y += syscalls_64.h +generated-y += unistd_32_ia32.h +generated-y += unistd_64_x32.h +generated-y += xen-hypercalls.h + genhdr-y += unistd_32.h genhdr-y += unistd_64.h genhdr-y += unistd_x32.h From cda2c65f981d0c29805fd01ffce441c650ffe6cf Mon Sep 17 00:00:00 2001 From: James Hogan Date: Fri, 24 Jun 2016 23:42:24 +0100 Subject: [PATCH 2/2] kbuild: Remove stale asm-generic wrappers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When a header file is removed from generic-y (often accompanied by the addition of an arch specific header), the generated wrapper file will persist, and in some cases may still take precedence over the new arch header. For example commit f1fe2d21f4e1 ("MIPS: Add definitions for extended context") removed ucontext.h from generic-y in arch/mips/include/asm/, and added an arch/mips/include/uapi/asm/ucontext.h. The continued use of the wrapper when reusing a dirty build tree resulted in build failures in arch/mips/kernel/signal.c: arch/mips/kernel/signal.c: In function ‘sc_to_extcontext’: arch/mips/kernel/signal.c:142:12: error: ‘struct ucontext’ has no member named ‘uc_extcontext’ return &uc->uc_extcontext; ^ Fix by detecting and removing wrapper headers in generated header directories that do not correspond to a filename in generic-y, genhdr-y, or the newly introduced generated-y. Reported-by: Jacek Anaszewski Reported-by: Hauke Mehrtens Reported-by: Heinrich Schuchardt Signed-off-by: James Hogan Acked-by: Arnd Bergmann Acked-by: Florian Fainelli Cc: linux-arch@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: Paul Burton Cc: linux-kbuild@vger.kernel.org Cc: Ralf Baechle Cc: Michal Marek Link: http://lkml.kernel.org/r/1466808144-23209-3-git-send-email-james.hogan@imgtec.com Signed-off-by: Thomas Gleixner --- scripts/Makefile.asm-generic | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/scripts/Makefile.asm-generic b/scripts/Makefile.asm-generic index 045e0098e962..e4d017d53819 100644 --- a/scripts/Makefile.asm-generic +++ b/scripts/Makefile.asm-generic @@ -13,11 +13,26 @@ include scripts/Kbuild.include # Create output directory if not already present _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) +# Stale wrappers when the corresponding files are removed from generic-y +# need removing. +generated-y := $(generic-y) $(genhdr-y) $(generated-y) +all-files := $(patsubst %, $(obj)/%, $(generated-y)) +old-headers := $(wildcard $(obj)/*.h) +unwanted := $(filter-out $(all-files),$(old-headers)) + quiet_cmd_wrap = WRAP $@ cmd_wrap = echo "\#include " >$@ -all: $(patsubst %, $(obj)/%, $(generic-y)) +quiet_cmd_remove = REMOVE $(unwanted) +cmd_remove = rm -f $(unwanted) + +all: $(patsubst %, $(obj)/%, $(generic-y)) FORCE + $(if $(unwanted),$(call cmd,remove),) @: $(obj)/%.h: $(call cmd,wrap) + +PHONY += FORCE +.PHONY: $(PHONY) +FORCE: ;