On Fri, Jul 22, 2016 at 11:37:39AM -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, Jul 21, 2016 at 10:41:18PM -0500, Josh Poimboeuf escreveu: > > On Fri, Jul 22, 2016 at 09:23:02AM +1000, Stephen Rothwell wrote: > > > It just looks like objtool was not written with cross compilation in > > > mind? > > > I don't know yet what the specific problem is, but objtool should work > > fine in a cross-compiled environment. It needs to be compiled with the > > host (powerpc) compiler, but then it needs to disassemble target (x86) > > files. It worked fine before the bitsperlong.h files were merged. > > So, trying to summarize from the various messages in this thread: > > In Tue, Jul 19, 2016 at 01:26:08PM +1000, Stephen Rothwell wrote: > > > It produces these errors (from the x86_64 allmodconfig build): > > > > In file included from > > /home/sfr/next/next/tools/arch/x86/include/uapi/asm/bitsperlong.h:10:0, > > from /usr/include/asm-generic/int-ll64.h:11, > > from /usr/include/powerpc64le-linux-gnu/asm/types.h:27, > > from /home/sfr/next/next/tools/include/linux/types.h:9, > > from /home/sfr/next/next/tools/include/linux/list.h:4, > > from elf.h:23, > > from elf.c:30: > > /home/sfr/next/next/tools/include/asm-generic/bitsperlong.h:13:2: > > error: #error Inconsistent word size. Check asm/bitsperlong.h > > #error Inconsistent word size. Check asm/bitsperlong.h > > ^ > > So it starts at tools/arch/x86/include/uapi/asm/bitsperlong.h, and as > you mention, this should've instead be using the host headers, i.e.: > > tools/arch/powerpc/include/uapi/asm/bitsperlong.h > > Which it will if it uses HOSTARCH in tools/objtool/Makefile when setting > up the header search path, I have two csets in my perf/core branch that > fixes this, and that are equivalent to the last patch Stephen tried: > > $ git log --oneline -2 > 87f7dc54366a objtool: Use tools/scripts/Makefile.arch to get ARCH and > HOSTARCH > 0eec6770ab60 tools build: Add HOSTARCH Makefile variable > $ > > Ok, so now it uses the right file, see the whole sequence at the end of this > e-mail, but it boils down to: > > ----------------------------------------------------------------------------- > #if defined(__powerpc64__) > # define __BITS_PER_LONG 64 > #else > # define __BITS_PER_LONG 32 > #endif > > #ifdef __SIZEOF_LONG__ > #define BITS_PER_LONG (__CHAR_BIT__ * __SIZEOF_LONG__) > #else > #define BITS_PER_LONG __WORDSIZE > #endif > > #if BITS_PER_LONG != __BITS_PER_LONG > #error Inconsistent word size. Check asm/bitsperlong.h > #endif > ----------------------------------------------------------------------------- > > Which I think has no problems, right? The last problem reported ty Stephen > now is: > > In Fri, 22 Jul 2016 09:23:02 +1000, Stephen Rothwell wrote: > > > That gets me this errors from the x86_64 allmodconfig build: > > > tools/objtool/objtool-in.o: In function `decode_instructions': > > tools/objtool/builtin-check.c:276: undefined reference to > > `arch_decode_instruction' > > Should work, since ARCH should be x86 and then tools/objtool/Build will have > this: > > objtool-y += arch/$(ARCH)/ > > Turned into: > > objtool-y += arch/x86/ > > Which will build tools/objtool/arch/x86/decode.c, that will provide that > arch_decode_instruction() function :-\ > > I.e. with the two patches I mentioned, that are equivalent to the last patch I > sent to Stephen for testing, we would end up with HOSTARCH=powerpc and > ARCH=x86, no?
Thanks for spelling it out, that helped a lot. I'm guessing Stephen is setting ARCH=x86_64 on the command-line rather than ARCH=x86. How about the following patch? Stephen, can you confirm this fixes it? This is on top of Arnaldo's other two fixes here: https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git perf/core From: Josh Poimboeuf <jpoim...@redhat.com> Subject: [PATCH] tools build: fix objtool build with ARCH=x86_64 The objtool build fails in a cross-compiled environment on a non-x86 host with "ARCH=x86_64": tools/objtool/objtool-in.o: In function `decode_instructions': tools/objtool/builtin-check.c:276: undefined reference to `arch_decode_instruction' We could override the ARCH environment variable and change it back to x86, similar to what the objtool Makefile was doing before; but it's tricky to override environment variables consistently. Instead, take a similar approach used by the Linux top-level Makefile and introduce a SRCARCH Makefile variable which evaluates to "x86" when ARCH is either "x86_64" or "x86". Reported-by: Stephen Rothwell <s...@canb.auug.org.au> Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com> --- tools/objtool/Build | 2 +- tools/objtool/Makefile | 2 +- tools/scripts/Makefile.arch | 32 ++++++++++++++++++++++++++++++++ 3 files changed, 34 insertions(+), 2 deletions(-) diff --git a/tools/objtool/Build b/tools/objtool/Build index 2457916..d6cdece 100644 --- a/tools/objtool/Build +++ b/tools/objtool/Build @@ -1,4 +1,4 @@ -objtool-y += arch/$(ARCH)/ +objtool-y += arch/$(SRCARCH)/ objtool-y += builtin-check.o objtool-y += elf.o objtool-y += special.o diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index c9ad80a..577f2d4 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -29,7 +29,7 @@ elfshdr := $(shell echo '\#include <libelf.h>' | $(CC) $(CFLAGS) -x c -E - | gre CFLAGS += $(if $(elfshdr),,-DLIBELF_USE_DEPRECATED) AWK = awk -export srctree OUTPUT CFLAGS ARCH AWK +export srctree OUTPUT CFLAGS SRCARCH AWK include $(srctree)/tools/build/Makefile.include $(OBJTOOL_IN): fixdep FORCE diff --git a/tools/scripts/Makefile.arch b/tools/scripts/Makefile.arch index 887321c..ad85b92 100644 --- a/tools/scripts/Makefile.arch +++ b/tools/scripts/Makefile.arch @@ -5,10 +5,42 @@ HOSTARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \ -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \ -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \ -e s/tile.*/tile/ ) + ifndef ARCH ARCH := $(HOSTARCH) endif +SRCARCH := $(ARCH) + +# Additional ARCH settings for x86 +ifeq ($(ARCH),i386) + SRCARCH := x86 +endif +ifeq ($(ARCH),x86_64) + SRCARCH := x86 +endif + +# Additional ARCH settings for sparc +ifeq ($(ARCH),sparc32) + SRCARCH := sparc +endif +ifeq ($(ARCH),sparc64) + SRCARCH := sparc +endif + +# Additional ARCH settings for sh +ifeq ($(ARCH),sh64) + SRCARCH := sh +endif + +# Additional ARCH settings for tile +ifeq ($(ARCH),tilepro) + SRCARCH := tile +endif +ifeq ($(ARCH),tilegx) + SRCARCH := tile +endif + LP64 := $(shell echo __LP64__ | ${CC} ${CFLAGS} -E -x c - | tail -n 1) ifeq ($(LP64), 1) IS_64_BIT := 1
