[fedora-arm] Building RHEL/Fedora Kernels on ARM

[Gordan Bobic]

On 12/22/2011 06:07 PM, Gordan Bobic wrote:
> On 12/22/2011 04:52 PM, Gordan Bobic wrote:
>> On 12/22/2011 04:42 PM, Jon Masters wrote:
>>> On Thu, 2011-12-22 at 14:56 +0000, Gordan Bobic wrote:
>>>
>>>> I'm trying to build a RHEL6 kernel from src.rpm on ARM and I think I
>>>> have it mostly sorted out, but it looks like the modules aren't getting
>>>> signed and since they weren't signed from<module>.ko.unsigned
>>>> <module>.ko the packaging part can't find the .ko files and the process
>>>> fails at the end.
>>>
>>> Module signing is fun since you need not only the rngd but gpg and a few
>>> other bits.
>>
>> Sure, I know that - I have both of those working.
>>
>>> Having said that, I thought it was supposed to disable if it
>>> didn't find those bits. It's been a while, I can look. Please send the
>>> whole log as well, since that's really the only way to ponder.
>>
>> Thanks, I appreciate it. I will attach the full log once the latest
>> build attempt has completed (I removed the -s from the make lines to be
>> able to better connect the errors/warnings with their causes).
>
> I have attached the full build log.
>
> It looks like the problem is in:
> scripts/mod/mod-extract

Actually, the problem appears to be in this line:

sh scripts/mod/modsign-note.sh 
sound/pci/hda/snd-hda-codec-cmedia.ko.digest.sig | \
gcc -x assembler-with-cpp 
-Wp,-MD,sound/pci/hda/.snd-hda-codec-cmedia.ko.d  -nostdinc -isystem 
/usr/lib/gcc/armv5tel-redhat-linux-gnueabi/4.4.5/include -Iinclude 
-I/usr/src/rhel6-stage1/root/rpmbuild/BUILD/kernel-2.6.32-71.29.1.el6/linux-2.6.32-71.29.1.el6.armv5tel/arch/arm/include 
-include include/linux/autoconf.h -D__KERNEL__ -mlittle-endian 
-Iarch/arm/mach-kirkwood/include -Iarch/arm/plat-orion/include -Wall 
-Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing 
-fno-common -Werror-implicit-function-declaration -Wno-format-security 
-fno-delete-null-pointer-checks -O2 -marm -mabi=aapcs-linux 
-mno-thumb-interwork -funwind-tables -D__LINUX_ARM_ARCH__=5 
-march=armv5te -mtune=xscale -msoft-float -Uarm -Wframe-larger-than=1024 
-fno-stack-protector -fomit-frame-pointer -g 
-Wdeclaration-after-statement -Wno-pointer-sign -fno-strict-overflow 
-fno-dwarf2-cfi-asm -fconserve-stack  -D"KBUILD_STR(s)=#s" 
-D"KBUILD_BASENAME=KBUILD_STR(snd_hda_codec_cmedia)" 
-D"KBUILD_MODNAME=KBUILD_STR(snd_hda_codec_cmedia.ko)" -D"DEBUG_HASH=23" 
-D"DEBUG_HASH2=54" -DMODULE -c -o 
sound/pci/hda/snd-hda-codec-cmedia.ko.note.o -

The modsign-note.sh script produces this:
#include <linux/modsign.h>

ELFNOTE(MODSIGN_NOTE_NAME, MODSIGN_NOTE_TYPE, .incbin 
"sound/pci/hda/snd-hda-codec-cmedia.ko.digest.sig")

and gcc proceeds to choke on it:
<stdin>:Assembler messages:
<stdin>:3: Error: junk at end of line, first unrecognized character is `,'


include/linux/modsign.h includes include/linux/elfnote.h

and this defines ELFNOTE either as:
#ifdef __ASSEMBLER__
[...]
#define ELFNOTE(name, type, desc)
[...]
#else
[...]
#define ELFNOTE(size, name, type, desc)
[...]
#endif

In this case __ASSEMBLER__ is defined, and the macro expects 3 arguments 
(tested it), so that means the relevant definition from elfnote.h is this:

#define ELFNOTE_START(name, type, flags)        \
.pushsection .note.name, flags, at note    ;       \
   .balign 4                             ;       \
   .long 2f - 1f         /* namesz */    ;       \
   .long 4484f - 3f      /* descsz */    ;       \
   .long type                            ;       \
1:.asciz #name                          ;       \
2:.balign 4                             ;       \
3:

#define ELFNOTE_END                             \
4484:.balign 4                          ;       \
.popsection                             ;

#define ELFNOTE(name, type, desc)               \
         ELFNOTE_START(name, type, "")           \
                 desc                    ;       \
         ELFNOTE_END

And unless I am mistaken, the ARM assembly @ comment bug strikes again.

This pseudopatch seems to fix it:

-.pushsection .note.name, flags, at note    ;       \
+.pushsection .note.name, flags          ;       \


Now to try again. :)

Gordan