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/$(ARCH)/ Turned into: objtool-y += arch/x86/ Which will build tools/objtool/arch/x86/decode.c, that will provide that arch_decode_instruction() function :-\ I.e. with the two patches I mentioned, that are equivalent to the last patch I sent to Stephen for testing, we would end up with HOSTARCH=powerpc and ARCH=x86, no? - Arnaldo Full sequence: [acme@jouet linux]$ cat tools/arch/powerpc/include/uapi/asm/bitsperlong.h #ifndef __ASM_POWERPC_BITSPERLONG_H #define __ASM_POWERPC_BITSPERLONG_H #if defined(__powerpc64__) # define __BITS_PER_LONG 64 #else # define __BITS_PER_LONG 32 #endif #include <asm-generic/bitsperlong.h> #endif /* __ASM_POWERPC_BITSPERLONG_H */ [acme@jouet linux]$ It, like the kernel, where these files come from, has: [acme@jouet linux]$ cat tools/include/asm-generic/bitsperlong.h #ifndef __ASM_GENERIC_BITS_PER_LONG #define __ASM_GENERIC_BITS_PER_LONG #include <uapi/asm-generic/bitsperlong.h> #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 #endif /* __ASM_GENERIC_BITS_PER_LONG */ [acme@jouet linux]$ And finally: [acme@jouet linux]$ cat tools/include/uapi/asm-generic/bitsperlong.h #ifndef _UAPI__ASM_GENERIC_BITS_PER_LONG #define _UAPI__ASM_GENERIC_BITS_PER_LONG /* * There seems to be no way of detecting this automatically from user * space, so 64 bit architectures should override this in their * bitsperlong.h. In particular, an architecture that supports * both 32 and 64 bit user space must not rely on CONFIG_64BIT * to decide it, but rather check a compiler provided macro. */ #ifndef __BITS_PER_LONG #define __BITS_PER_LONG 32 #endif #endif /* _UAPI__ASM_GENERIC_BITS_PER_LONG */ [acme@jouet linux]$ -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
