Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Kent Overstreet]

On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
>    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
>    die__process_unit: tag not supported 0xd (member)!
>    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
>    die__process_function: tag not supported 0x11 (compile_unit)!
>    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
>    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
>    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
>    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
>    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
>    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

Not sure how likely a header cleanup is to cause a segfault in
llvm-objcopy and I don't have the toolchain to repro this - could
hexagon people take a look?

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Nick Desaulniers]

On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
<kent.overstreet@linux.dev> wrote:
>
> On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> >
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> >
> > All errors (new ones prefixed by >>):
> >
> >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> >    die__process_unit: tag not supported 0xd (member)!
> >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> >    die__process_function: tag not supported 0x11 (compile_unit)!
> >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
>
> Not sure how likely a header cleanup is to cause a segfault in
> llvm-objcopy and I don't have the toolchain to repro this - could
> hexagon people take a look?
>

Is it a segfault in llvm-objcopy, or pahole?
-- 
Thanks,
~Nick Desaulniers

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Kent Overstreet]

On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> <kent.overstreet@linux.dev> wrote:
> >
> > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > >
> > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > the same patch/commit), kindly add following tags
> > > | Reported-by: kernel test robot <lkp@intel.com>
> > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> > >
> > > All errors (new ones prefixed by >>):
> > >
> > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > >    die__process_unit: tag not supported 0xd (member)!
> > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> >
> > Not sure how likely a header cleanup is to cause a segfault in
> > llvm-objcopy and I don't have the toolchain to repro this - could
> > hexagon people take a look?
> >
> 
> Is it a segfault in llvm-objcopy, or pahole?

Whoops, I think you're right :)

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Nathan Chancellor]

On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> <kent.overstreet@linux.dev> wrote:
> >
> > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > >
> > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > the same patch/commit), kindly add following tags
> > > | Reported-by: kernel test robot <lkp@intel.com>
> > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> > >
> > > All errors (new ones prefixed by >>):
> > >
> > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > >    die__process_unit: tag not supported 0xd (member)!
> > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> >
> > Not sure how likely a header cleanup is to cause a segfault in
> > llvm-objcopy and I don't have the toolchain to repro this - could
> > hexagon people take a look?

For what it's worth in case you were not aware, I provide copies of LLVM
on kernel.org that can be installed in some prefix and invoked with
LLVM=<prefix>/bin/, which can make reproducing reports such as these
relatively easy.

https://mirrors.edge.kernel.org/pub/tools/llvm/

> Is it a segfault in llvm-objcopy, or pahole?

Should be pahole. I have not been able to reproduce these crashes in
pahole v1.25 in the past when they come up every so often. 0day folks,
what version of pahole are you testing with?

Cheers,
Nathan

RE: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eep...

[Brian Cain]

> -----Original Message-----
> From: Nathan Chancellor <nathan@kernel.org>
> Sent: Tuesday, December 19, 2023 3:05 PM
> To: Nick Desaulniers <ndesaulniers@google.com>; Kent Overstreet
> <kent.overstreet@linux.dev>; kernel test robot <lkp@intel.com>
> Cc: llvm@lists.linux.dev; oe-kbuild-all@lists.linux.dev; Brian Cain
> <bcain@quicinc.com>; linux-hexagon@vger.kernel.org
> Subject: Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420
> Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j
> --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --
> btf_gen_optimized --btf_base vmlinux drivers/misc/eep...
> 
> WARNING: This email originated from outside of Qualcomm. Please be wary of
> any links or attachments, and do not enable macros.
> 
> On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> > On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> > <kent.overstreet@linux.dev> wrote:
> > >
> > > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51]
> locking/seqlock: Split out seqlock_types.h
> > > > config: hexagon-randconfig-r005-20220913
> (https://download.01.org/0day-
> ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git
> ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > > reproduce (this is a W=1 build): (https://download.01.org/0day-
> ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > > >
> > > > If you fix the issue in a separate patch/commit (i.e. not just a new version
> of
> > > > the same patch/commit), kindly add following tags
> > > > | Reported-by: kernel test robot <lkp@intel.com>
> > > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-
> lkp@intel.com/
> > > >
> > > > All errors (new ones prefixed by >>):
> > > >
> > > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > > >    die__process_unit: tag not supported 0xd (member)!
> > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not
> handled!
> > > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not
> handled!
> > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not
> handled!
> > > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not
> handled!
> > > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b
> (member)!
> > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674
> (member)!
> > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e
> (member)!
> > > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-
> objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --
> skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux
> drivers/misc/eeprom/at24.ko
> > >
> > > Not sure how likely a header cleanup is to cause a segfault in
> > > llvm-objcopy and I don't have the toolchain to repro this - could
> > > hexagon people take a look?
> 
> For what it's worth in case you were not aware, I provide copies of LLVM
> on kernel.org that can be installed in some prefix and invoked with
> LLVM=<prefix>/bin/, which can make reproducing reports such as these
> relatively easy.
> 
> https://mirrors.edge.kernel.org/pub/tools/llvm/
> 
> > Is it a segfault in llvm-objcopy, or pahole?
> 
> Should be pahole. I have not been able to reproduce these crashes in
> pahole v1.25 in the past when they come up every so often. 0day folks,

Is pahole strictly architecture independent (using only ELF/DWARF info)?  Or could we need to contribute something for hexagon in order to make this succeed?

> what version of pahole are you testing with?
> 
> Cheers,
> Nathan

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Yujie Liu]

On Tue, Dec 19, 2023 at 02:04:54PM -0700, Nathan Chancellor wrote:
> On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> > On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> > <kent.overstreet@linux.dev> wrote:
> > >
> > > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > > > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > > >
> > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > the same patch/commit), kindly add following tags
> > > > | Reported-by: kernel test robot <lkp@intel.com>
> > > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> > > >
> > > > All errors (new ones prefixed by >>):
> > > >
> > > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > > >    die__process_unit: tag not supported 0xd (member)!
> > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> > > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> > > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> > > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> > >
> > > Not sure how likely a header cleanup is to cause a segfault in
> > > llvm-objcopy and I don't have the toolchain to repro this - could
> > > hexagon people take a look?
> 
> For what it's worth in case you were not aware, I provide copies of LLVM
> on kernel.org that can be installed in some prefix and invoked with
> LLVM=<prefix>/bin/, which can make reproducing reports such as these
> relatively easy.
> 
> https://mirrors.edge.kernel.org/pub/tools/llvm/
> 
> > Is it a segfault in llvm-objcopy, or pahole?
> 
> Should be pahole. I have not been able to reproduce these crashes in
> pahole v1.25 in the past when they come up every so often. 0day folks,
> what version of pahole are you testing with?

We clone pahole source code from [1] and build it on the master branch.
The current head is commit c129fa757948 which is newer than v1.25.

c129fa757948 ("pahole: Add --btf_features_strict to reject unknown BTF features")

[1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git

Thanks,
Yujie

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Nathan Chancellor]

+ Arnaldo and dwarves list

On Wed, Dec 20, 2023 at 03:24:54PM +0800, Yujie Liu wrote:
> On Tue, Dec 19, 2023 at 02:04:54PM -0700, Nathan Chancellor wrote:
> > On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> > > On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> > > <kent.overstreet@linux.dev> wrote:
> > > >
> > > > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > > > > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > > > >
> > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > > the same patch/commit), kindly add following tags
> > > > > | Reported-by: kernel test robot <lkp@intel.com>
> > > > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> > > > >
> > > > > All errors (new ones prefixed by >>):
> > > > >
> > > > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > > > >    die__process_unit: tag not supported 0xd (member)!
> > > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> > > > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > > > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> > > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> > > > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> > > > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> > > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> > > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > > > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> > > >
> > > > Not sure how likely a header cleanup is to cause a segfault in
> > > > llvm-objcopy and I don't have the toolchain to repro this - could
> > > > hexagon people take a look?
> > 
> > For what it's worth in case you were not aware, I provide copies of LLVM
> > on kernel.org that can be installed in some prefix and invoked with
> > LLVM=<prefix>/bin/, which can make reproducing reports such as these
> > relatively easy.
> > 
> > https://mirrors.edge.kernel.org/pub/tools/llvm/
> > 
> > > Is it a segfault in llvm-objcopy, or pahole?
> > 
> > Should be pahole. I have not been able to reproduce these crashes in
> > pahole v1.25 in the past when they come up every so often. 0day folks,
> > what version of pahole are you testing with?
> 
> We clone pahole source code from [1] and build it on the master branch.
> The current head is commit c129fa757948 which is newer than v1.25.
> 
> c129fa757948 ("pahole: Add --btf_features_strict to reject unknown BTF features")
> 
> [1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git

Thanks for that additional information but I can reproduce this at v1.25
as well, I just tried:

  $ git fetch https://evilpiepirate.org/git/bcachefs.git 1db61740aeb7d6b1c7bfb2a98708a65a6679d068
  $ git reset --hard FETCH_HEAD
  $ curl -LSso .config https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config
  $ curl -LSs https://mirrors.edge.kernel.org/pub/tools/llvm/files/llvm-16.0.6-x86_64.tar.xz | tar -xJf -
  $ make -skj"$(nproc)" ARCH=hexagon LLVM=$PWD/llvm-16.0.6-x86_64/bin/ olddefconfig all
  ...
  die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
  die__create_new_enumeration: DW_TAG_array_type (0x1) @ <0x120b1> not handled!
  die__create_new_enumeration: DW_TAG_pointer_type (0xf) @ <0x120b7> not handled!
  die__process_unit: DW_TAG_member (0xd) @ <0x3669> not handled!
  die__process_unit: tag not supported 0xd (member)!
  die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
  die__process_unit: DW_TAG_member (0xd) @ <0x3650> not handled!
  die__process_unit: tag not supported 0xd (member)!
  die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
  die__create_new_enumeration: DW_TAG_array_type (0x1) @ <0x9cb5> not handled!
  die__create_new_enumeration: DW_TAG_pointer_type (0xf) @ <0x9cbb> not handled!
  die__process_unit: DW_TAG_enumerator (0x28) @ <0x705a> not handled!
  die__process_unit: tag not supported 0x28 (enumerator)!
  ...

I do not get a segfault personally but there are definitely a lot of
errors from pahole at the end. Arnaldo, is pahole not handling something
that it should with regards to clang's debug info?

Cheers,
Nathan

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Arnaldo Carvalho de Melo]

Em Wed, Dec 27, 2023 at 03:43:38PM -0700, Nathan Chancellor escreveu:
> + Arnaldo and dwarves list
> 
> On Wed, Dec 20, 2023 at 03:24:54PM +0800, Yujie Liu wrote:
> > On Tue, Dec 19, 2023 at 02:04:54PM -0700, Nathan Chancellor wrote:
> > > On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> > > > On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> > > > <kent.overstreet@linux.dev> wrote:
> > > > >
> > > > > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > > > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > > > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > > > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > > > > > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > > > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > > > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > > > > >
> > > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > > > the same patch/commit), kindly add following tags
> > > > > > | Reported-by: kernel test robot <lkp@intel.com>
> > > > > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> > > > > >
> > > > > > All errors (new ones prefixed by >>):
> > > > > >
> > > > > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > > > > >    die__process_unit: tag not supported 0xd (member)!
> > > > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> > > > > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > > > > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> > > > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> > > > > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> > > > > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> > > > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> > > > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > > > > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> > > > >
> > > > > Not sure how likely a header cleanup is to cause a segfault in
> > > > > llvm-objcopy and I don't have the toolchain to repro this - could
> > > > > hexagon people take a look?
> > > 
> > > For what it's worth in case you were not aware, I provide copies of LLVM
> > > on kernel.org that can be installed in some prefix and invoked with
> > > LLVM=<prefix>/bin/, which can make reproducing reports such as these
> > > relatively easy.
> > > 
> > > https://mirrors.edge.kernel.org/pub/tools/llvm/
> > > 
> > > > Is it a segfault in llvm-objcopy, or pahole?
> > > 
> > > Should be pahole. I have not been able to reproduce these crashes in
> > > pahole v1.25 in the past when they come up every so often. 0day folks,
> > > what version of pahole are you testing with?
> > 
> > We clone pahole source code from [1] and build it on the master branch.
> > The current head is commit c129fa757948 which is newer than v1.25.
> > 
> > c129fa757948 ("pahole: Add --btf_features_strict to reject unknown BTF features")
> > 
> > [1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git
> 
> Thanks for that additional information but I can reproduce this at v1.25
> as well, I just tried:
> 
>   $ git fetch https://evilpiepirate.org/git/bcachefs.git 1db61740aeb7d6b1c7bfb2a98708a65a6679d068
>   $ git reset --hard FETCH_HEAD
>   $ curl -LSso .config https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config
>   $ curl -LSs https://mirrors.edge.kernel.org/pub/tools/llvm/files/llvm-16.0.6-x86_64.tar.xz | tar -xJf -
>   $ make -skj"$(nproc)" ARCH=hexagon LLVM=$PWD/llvm-16.0.6-x86_64/bin/ olddefconfig all
>   ...
>   die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
>   die__create_new_enumeration: DW_TAG_array_type (0x1) @ <0x120b1> not handled!
>   die__create_new_enumeration: DW_TAG_pointer_type (0xf) @ <0x120b7> not handled!
>   die__process_unit: DW_TAG_member (0xd) @ <0x3669> not handled!
>   die__process_unit: tag not supported 0xd (member)!
>   die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
>   die__process_unit: DW_TAG_member (0xd) @ <0x3650> not handled!
>   die__process_unit: tag not supported 0xd (member)!
>   die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
>   die__create_new_enumeration: DW_TAG_array_type (0x1) @ <0x9cb5> not handled!
>   die__create_new_enumeration: DW_TAG_pointer_type (0xf) @ <0x9cbb> not handled!
>   die__process_unit: DW_TAG_enumerator (0x28) @ <0x705a> not handled!
>   die__process_unit: tag not supported 0x28 (enumerator)!
>   ...
> 
> I do not get a segfault personally but there are definitely a lot of
> errors from pahole at the end. Arnaldo, is pahole not handling something
> that it should with regards to clang's debug info?

Possibly, would it be possible to provide the vmlinux file where pahole
is segfaulting when trying to encode BTF from DWARF?

These two files:

vmlinux drivers/misc/eeprom/at24.ko

So that I can run:

LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

Here.

- Arnaldo

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Nathan Chancellor]

On Thu, Dec 28, 2023 at 11:21:06AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Wed, Dec 27, 2023 at 03:43:38PM -0700, Nathan Chancellor escreveu:
> > + Arnaldo and dwarves list
> > 
> > On Wed, Dec 20, 2023 at 03:24:54PM +0800, Yujie Liu wrote:
> > > On Tue, Dec 19, 2023 at 02:04:54PM -0700, Nathan Chancellor wrote:
> > > > On Tue, Dec 19, 2023 at 12:58:28PM -0800, Nick Desaulniers wrote:
> > > > > On Tue, Dec 19, 2023 at 12:54 PM Kent Overstreet
> > > > > <kent.overstreet@linux.dev> wrote:
> > > > > >
> > > > > > On Tue, Dec 19, 2023 at 09:40:09PM +0800, kernel test robot wrote:
> > > > > > > tree:   https://evilpiepirate.org/git/bcachefs.git header_cleanup
> > > > > > > head:   89188fceb7a49e3c4b0578d86f6f6e647f202821
> > > > > > > commit: 1db61740aeb7d6b1c7bfb2a98708a65a6679d068 [21/51] locking/seqlock: Split out seqlock_types.h
> > > > > > > config: hexagon-randconfig-r005-20220913 (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config)
> > > > > > > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
> > > > > > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/reproduce)
> > > > > > >
> > > > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > > > > the same patch/commit), kindly add following tags
> > > > > > > | Reported-by: kernel test robot <lkp@intel.com>
> > > > > > > | Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
> > > > > > >
> > > > > > > All errors (new ones prefixed by >>):
> > > > > > >
> > > > > > >    die__process_unit: DW_TAG_member (0xd) @ <0xc689> not handled!
> > > > > > >    die__process_unit: tag not supported 0xd (member)!
> > > > > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc697> not handled!
> > > > > > >    die__process_function: tag not supported 0x11 (compile_unit)!
> > > > > > >    die__process_function: DW_TAG_member (0xd) @ <0xc6db> not handled!
> > > > > > >    die__process_function: DW_TAG_compile_unit (0x11) @ <0xc6e5> not handled!
> > > > > > >    die__process_class: DW_TAG_compile_unit (0x11) @ <0xc778> not handled!
> > > > > > >    namespace__recode_dwarf_types: couldn't find 0xc689 type for 0xc66b (member)!
> > > > > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc674 (member)!
> > > > > > >    namespace__recode_dwarf_types: couldn't find 0xc638 type for 0xc67e (member)!
> > > > > > > >> /bin/bash: line 1: 19420 Segmentation fault      LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> > > > > >
> > > > > > Not sure how likely a header cleanup is to cause a segfault in
> > > > > > llvm-objcopy and I don't have the toolchain to repro this - could
> > > > > > hexagon people take a look?
> > > > 
> > > > For what it's worth in case you were not aware, I provide copies of LLVM
> > > > on kernel.org that can be installed in some prefix and invoked with
> > > > LLVM=<prefix>/bin/, which can make reproducing reports such as these
> > > > relatively easy.
> > > > 
> > > > https://mirrors.edge.kernel.org/pub/tools/llvm/
> > > > 
> > > > > Is it a segfault in llvm-objcopy, or pahole?
> > > > 
> > > > Should be pahole. I have not been able to reproduce these crashes in
> > > > pahole v1.25 in the past when they come up every so often. 0day folks,
> > > > what version of pahole are you testing with?
> > > 
> > > We clone pahole source code from [1] and build it on the master branch.
> > > The current head is commit c129fa757948 which is newer than v1.25.
> > > 
> > > c129fa757948 ("pahole: Add --btf_features_strict to reject unknown BTF features")
> > > 
> > > [1] https://git.kernel.org/pub/scm/devel/pahole/pahole.git
> > 
> > Thanks for that additional information but I can reproduce this at v1.25
> > as well, I just tried:
> > 
> >   $ git fetch https://evilpiepirate.org/git/bcachefs.git 1db61740aeb7d6b1c7bfb2a98708a65a6679d068
> >   $ git reset --hard FETCH_HEAD
> >   $ curl -LSso .config https://download.01.org/0day-ci/archive/20231219/202312192107.wMIKiZWw-lkp@intel.com/config
> >   $ curl -LSs https://mirrors.edge.kernel.org/pub/tools/llvm/files/llvm-16.0.6-x86_64.tar.xz | tar -xJf -
> >   $ make -skj"$(nproc)" ARCH=hexagon LLVM=$PWD/llvm-16.0.6-x86_64/bin/ olddefconfig all
> >   ...
> >   die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
> >   die__create_new_enumeration: DW_TAG_array_type (0x1) @ <0x120b1> not handled!
> >   die__create_new_enumeration: DW_TAG_pointer_type (0xf) @ <0x120b7> not handled!
> >   die__process_unit: DW_TAG_member (0xd) @ <0x3669> not handled!
> >   die__process_unit: tag not supported 0xd (member)!
> >   die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
> >   die__process_unit: DW_TAG_member (0xd) @ <0x3650> not handled!
> >   die__process_unit: tag not supported 0xd (member)!
> >   die__process: got compile_unit unexpected tag after DW_TAG_compile_unit!
> >   die__create_new_enumeration: DW_TAG_array_type (0x1) @ <0x9cb5> not handled!
> >   die__create_new_enumeration: DW_TAG_pointer_type (0xf) @ <0x9cbb> not handled!
> >   die__process_unit: DW_TAG_enumerator (0x28) @ <0x705a> not handled!
> >   die__process_unit: tag not supported 0x28 (enumerator)!
> >   ...
> > 
> > I do not get a segfault personally but there are definitely a lot of
> > errors from pahole at the end. Arnaldo, is pahole not handling something
> > that it should with regards to clang's debug info?
> 
> Possibly, would it be possible to provide the vmlinux file where pahole
> is segfaulting when trying to encode BTF from DWARF?
> 
> These two files:
> 
> vmlinux drivers/misc/eeprom/at24.ko
> 
> So that I can run:
> 
> LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
> 
> Here.

Sure, here you go:

https://1drv.ms/u/s!AsQNYeB-IEbqqAilUuGHOU8BMLbf

If you need more objects, just let me know. That series of commands in
the previous email should also get them for you locally if you need all
of them or want to investigate more.

Cheers,
Nathan

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Arnaldo Carvalho de Melo]

Em Thu, Dec 28, 2023 at 10:34:04AM -0700, Nathan Chancellor escreveu:
> On Thu, Dec 28, 2023 at 11:21:06AM -0300, Arnaldo Carvalho de Melo wrote:
> > Em Wed, Dec 27, 2023 at 03:43:38PM -0700, Nathan Chancellor escreveu:
> > > I do not get a segfault personally but there are definitely a lot of
> > > errors from pahole at the end. Arnaldo, is pahole not handling something
> > > that it should with regards to clang's debug info?

> > Possibly, would it be possible to provide the vmlinux file where pahole
> > is segfaulting when trying to encode BTF from DWARF?

> > These two files:

> > vmlinux drivers/misc/eeprom/at24.ko

> > So that I can run:
> > LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
 
> Sure, here you go:
 
> https://1drv.ms/u/s!AsQNYeB-IEbqqAilUuGHOU8BMLbf
 
> If you need more objects, just let me know. That series of commands in
> the previous email should also get them for you locally if you need all
> of them or want to investigate more.

llvm-dwarfdump is the only that is managing to process this file on a
fedora:39 system, more work needed to figure out if this is something
elfutils is planning to support, what amount of work would be necessary,
etc.

Mark, do you know about work on elfutils to support:

⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-dwarfdump at24.ko | head -22
at24.ko:        file format elf32-hexagon

.debug_info contents:
0x00000000: Compile Unit: length = 0x0000c634, format = DWARF32, version = 0x0005, unit_type = DW_UT_compile, abbr_offset = 0x0000, addr_size = 0x04 (next unit at 0x0000c638)

Cheers,

- Arnaldo

⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ eu-readelf --version
eu-readelf (elfutils) 0.190
Copyright (C) 2023 The elfutils developers <http://elfutils.org/>.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]

⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ eu-readelf -winfo at24.ko  > /dev/null
eu-readelf: DIE [c644] cannot get attribute 'addr_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c644] cannot get attribute 'rnglists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c644] cannot get attribute 'loclists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c674] cannot get attribute 'name' (strx2) value: invalid offset
eu-readelf: DIE [c67e] cannot get attribute 'name' (strx2) value: invalid offset
eu-readelf: DIE [c689] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c697] cannot get attribute 'str_offsets_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c697] cannot get attribute 'stmt_list' (sec_offset) value: invalid offset
eu-readelf: DIE [c697] cannot get attribute 'addr_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c697] cannot get attribute 'rnglists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c697] cannot get attribute 'loclists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c6bb] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c6c3] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c6db] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c6e5] cannot get attribute 'str_offsets_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c6e5] cannot get attribute 'stmt_list' (sec_offset) value: invalid offset
eu-readelf: DIE [c6e5] cannot get attribute 'addr_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c6e5] cannot get attribute 'rnglists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c6e5] cannot get attribute 'loclists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c704] cannot get attribute 'name' (strx2) value: invalid offset
eu-readelf: DIE [c70e] cannot get attribute 'name' (strx2) value: invalid offset
eu-readelf: DIE [c75c] cannot get attribute 'name' (strx2) value: invalid offset
eu-readelf: DIE [c762] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c767] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c773] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c778] cannot get attribute 'str_offsets_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c778] cannot get attribute 'stmt_list' (sec_offset) value: invalid offset
eu-readelf: DIE [c778] cannot get attribute 'addr_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c778] cannot get attribute 'rnglists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c778] cannot get attribute 'loclists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c797] cannot get attribute 'stmt_list' (sec_offset) value: invalid offset
eu-readelf: DIE [c797] cannot get attribute 'addr_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c797] cannot get attribute 'rnglists_base' (sec_offset) value: invalid offset
eu-readelf: DIE [c7b6] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c7c1] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c7c6] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c7cc] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: DIE [c7d7] cannot get attribute 'type' (ref4) value: invalid DWARF
eu-readelf: cannot get tag of DIE at offset [c7de] in section '.debug_info': invalid DWARF
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$


⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ readelf --version
GNU readelf version 2.40-13.fc39
Copyright (C) 2023 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) any later version.
This program has absolutely no warranty.
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$

⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ readelf -wi at24.ko  > /dev/null
readelf: at24.ko: Error: Missing knowledge of 32-bit reloc types used in DWARF sections of machine number 164
readelf: at24.ko: Warning: unable to apply unsupported reloc type 6 to section .debug_info
readelf: at24.ko: Warning: string index of 10 converts to an offset of 0x2000028 which is too big for section .debug_strreadelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x40e0000 and 0x7e09)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0x300a102 and 0xd020800)readelf: at24.ko: Warning: CU @ 0xc638 has multiple str_offsets_base values 0x2000000 and 0xf000000)readelf: at24.ko: Warning: string index of 3 converts to an offset of 0xf00000c which is too big for section .debug_strreadelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x7e09 and 0x5104)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0xd020800 and 0xf0000)readelf: at24.ko: Warning: CU @ 0xc638 has multiple str_offsets_base values 0xf000000 and 0x3000003)readelf: at24.ko: Warning: string index of 33 converts to an offset of 0x3000087 which is too big for section .debug_strreadelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x5104 and 0x2d000312)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0xf0000 and 0xa2030000)readelf: at24.ko: Warning: CU @ 0xc638 has multiple str_offsets_base values 0x3000003 and 0x452)readelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x2d000312 and 0x3191084)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0xa2030000 and 0x457)readelf: at24.ko: Warning: DIE at offset 0xc7de refers to abbreviation number 5568 which does not exist
readelf: at24.ko: Warning: loc_offset 0 too big
readelf: at24.ko: Warning: loc_offset 1 too big
readelf: at24.ko: Warning: loc_offset 2 too big
readelf: at24.ko: Warning: loc_offset 3 too big
readelf: at24.ko: Warning: loc_offset 4 too big
readelf: at24.ko: Warning: loc_offset 5 too big
readelf: at24.ko: Warning: loc_offset 6 too big
readelf: at24.ko: Warning: loc_offset 7 too big
readelf: at24.ko: Warning: loc_offset 8 too big
readelf: at24.ko: Warning: loc_offset 9 too big
readelf: at24.ko: Warning: loc_offset 10 too big
readelf: at24.ko: Warning: loc_offset 11 too big
readelf: at24.ko: Warning: loc_offset 12 too big
readelf: at24.ko: Warning: loc_offset 13 too big
readelf: at24.ko: Warning: loc_offset 14 too big
readelf: at24.ko: Warning: loc_offset 15 too big
readelf: at24.ko: Warning: loc_offset 16 too big
readelf: at24.ko: Warning: loc_offset 17 too big
readelf: at24.ko: Warning: loc_offset 18 too big
readelf: at24.ko: Warning: loc_offset 19 too big
readelf: at24.ko: Warning: loc_offset 20 too big
readelf: at24.ko: Warning: loc_offset 21 too big
readelf: at24.ko: Warning: loc_offset 22 too big
readelf: at24.ko: Warning: loc_offset 23 too big
readelf: at24.ko: Warning: loc_offset 24 too big
readelf: at24.ko: Warning: loc_offset 27 too big
readelf: at24.ko: Warning: loc_offset 28 too big
readelf: at24.ko: Warning: loc_offset 29 too big
readelf: at24.ko: Warning: loc_offset 30 too big
readelf: at24.ko: Warning: loc_offset 31 too big
readelf: at24.ko: Warning: loc_offset 32 too big
readelf: at24.ko: Warning: loc_offset 33 too big
readelf: at24.ko: Warning: loc_offset 34 too big
readelf: at24.ko: Warning: loc_offset 35 too big
readelf: at24.ko: Warning: loc_offset 41 too big
readelf: at24.ko: Warning: loc_offset 40 too big
readelf: at24.ko: Warning: loc_offset 36 too big
readelf: at24.ko: Warning: loc_offset 37 too big
readelf: at24.ko: Warning: loc_offset 38 too big
readelf: at24.ko: Warning: loc_offset 39 too big
readelf: at24.ko: Warning: loc_offset 46 too big
readelf: at24.ko: Warning: loc_offset 45 too big
readelf: at24.ko: Warning: loc_offset 44 too big
readelf: at24.ko: Warning: loc_offset 47 too big
readelf: at24.ko: Warning: loc_offset 48 too big
readelf: at24.ko: Warning: loc_offset 49 too big
readelf: at24.ko: Warning: loc_offset 50 too big
readelf: at24.ko: Warning: loc_offset 51 too big
readelf: at24.ko: Warning: loc_offset 52 too big
readelf: at24.ko: Warning: loc_offset 53 too big
readelf: at24.ko: Warning: loc_offset 54 too big
readelf: at24.ko: Warning: loc_offset 55 too big
readelf: at24.ko: Warning: loc_offset 56 too big
readelf: at24.ko: Warning: loc_offset 57 too big
readelf: at24.ko: Warning: loc_offset 58 too big
readelf: at24.ko: Warning: loc_offset 59 too big
readelf: at24.ko: Warning: loc_offset 60 too big
readelf: at24.ko: Warning: loc_offset 61 too big
readelf: at24.ko: Warning: loc_offset 66 too big
readelf: at24.ko: Warning: loc_offset 65 too big
readelf: at24.ko: Warning: Unable to resolve ref form: uvalue ce020c0b + cu_offset c638 > CU size 1003e
readelf: at24.ko: Warning: string index of 35340 converts to an offset of 0x22830 which is too big for section .debug_strreadelf: at24.ko: Warning: Unable to resolve ref form: uvalue 50000 + cu_offset c638 > CU size 1003e
readelf: at24.ko: Warning: string index of 40463 converts to an offset of 0x2783c which is too big for section .debug_strreadelf: at24.ko: Warning: Unable to resolve ref form: uvalue 50000 + cu_offset c638 > CU size 1003e
readelf: at24.ko: Warning: string index of 10 converts to an offset of 0x2000028 which is too big for section .debug_strreadelf: at24.ko: Warning: Offset into section .debug_rnglists too big: 0x40e0008
readelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x40e0000 and 0x7e09)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0x300a102 and 0xd020800)readelf: at24.ko: Warning: string index of 0 converts to an offset of 0x2000000 which is too big for section .debug_strreadelf: at24.ko: Warning: Unable to resolve ref form: uvalue 9a0c + cu_offset c638 > CU size 1003e
readelf: at24.ko: Warning: string index of 154 converts to an offset of 0x2000268 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 2 converts to an offset of 0x2000008 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 0 converts to an offset of 0x2000000 which is too big for section .debug_strreadelf: at24.ko: Warning: CU @ 0xc638 has multiple str_offsets_base values 0x2000000 and 0xf000000)readelf: at24.ko: Warning: string index of 3 converts to an offset of 0xf00000c which is too big for section .debug_strreadelf: at24.ko: Warning: Offset into section .debug_rnglists too big: 0x7e19
readelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x7e09 and 0x5104)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0xd020800 and 0xf0000)readelf: at24.ko: Warning: string index of 35340 converts to an offset of 0xf022830 which is too big for section .debug_strreadelf: at24.ko: Warning: Unable to resolve ref form: uvalue 50000 + cu_offset c638 > CU size 1003e
readelf: at24.ko: Warning: string index of 57615 converts to an offset of 0xf03843c which is too big for section .debug_strreadelf: at24.ko: Warning: Unable to resolve ref form: uvalue 50000 + cu_offset c638 > CU size 1003e
readelf: at24.ko: Warning: string index of 18 converts to an offset of 0xf000048 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 19 converts to an offset of 0xf00004c which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 253 converts to an offset of 0xf0003f4 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 768 converts to an offset of 0xf000c00 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 20 converts to an offset of 0xf000050 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 253 converts to an offset of 0xf0003f4 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 0 converts to an offset of 0xf000000 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 1 converts to an offset of 0xf000004 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 45583 converts to an offset of 0xf02c83c which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 854 converts to an offset of 0xf000d58 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 4 converts to an offset of 0xf000010 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 138 converts to an offset of 0xf000228 which is too big for section .debug_strreadelf: at24.ko: Warning: CU @ 0xc638 has multiple str_offsets_base values 0xf000000 and 0x3000003)readelf: at24.ko: Warning: string index of 33 converts to an offset of 0x3000087 which is too big for section .debug_strreadelf: at24.ko: Warning: Offset into section .debug_rnglists too big: 0x5110
readelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x5104 and 0x2d000312)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0xf0000 and 0xa2030000)readelf: at24.ko: Warning: string index of 124 converts to an offset of 0x30001f3 which is too big for section .debug_strreadelf: at24.ko: Warning: string index of 3 converts to an offset of 0x300000f which is too big for section .debug_strreadelf: at24.ko: Warning: CU @ 0xc638 has multiple str_offsets_base values 0x3000003 and 0x452)readelf: at24.ko: Warning: Offset into section .debug_rnglists too big: 0x2d000312
readelf: at24.ko: Warning: CU @ 0xc638 has multiple rnglists_base values (0x2d000312 and 0x3191084)readelf: at24.ko: Warning: CU @ 0xc638 has multiple loclists_base values (0xa2030000 and 0x457)readelf: at24.ko: Warning: DIE at offset 0xc7de refers to abbreviation number 5568 which does not exist
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$


But:

⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-dwarfdump --version
LLVM (http://llvm.org/):
  LLVM version 17.0.6
  Optimized build.
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-dwarfdump at24.ko > /dev/null
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$

⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-dwarfdump at24.ko | head -22
at24.ko:	file format elf32-hexagon

.debug_info contents:
0x00000000: Compile Unit: length = 0x0000c634, format = DWARF32, version = 0x0005, unit_type = DW_UT_compile, abbr_offset = 0x0000, addr_size = 0x04 (next unit at 0x0000c638)

0x0000000c: DW_TAG_compile_unit
              DW_AT_producer	("ClangBuiltLinux clang version 16.0.6 (https://github.com/llvm/llvm-project 7cbf1a2591520c2491aa35339f227775f4d3adf6)")
              DW_AT_language	(DW_LANG_C11)
              DW_AT_name	("/home/nathan/cbl/src/linux/drivers/misc/eeprom/at24.c")
              DW_AT_str_offsets_base	(0x00000008)
              DW_AT_stmt_list	(0x00000000)
              DW_AT_comp_dir	("/mnt/nvme/tmp/build/linux")
              DW_AT_low_pc	(0x00000000)
              DW_AT_ranges	(indexed (0x8) rangelist = 0x00000090
                 [0x00000000, 0x00000058)
                 [0x00000000, 0x00000014)
                 [0x00000000, 0x000008a8))
              DW_AT_addr_base	(0x00000008)
              DW_AT_rnglists_base	(0x0000000c)
              DW_AT_loclists_base	(0x0000000c)

0x0000002b:   DW_TAG_variable
⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Mark Wielaard]

Hi Arnaldo,

On Tue, Jan 02, 2024 at 01:30:02PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Thu, Dec 28, 2023 at 10:34:04AM -0700, Nathan Chancellor escreveu:
> > On Thu, Dec 28, 2023 at 11:21:06AM -0300, Arnaldo Carvalho de Melo wrote:
> > > Em Wed, Dec 27, 2023 at 03:43:38PM -0700, Nathan Chancellor escreveu:
> > > > I do not get a segfault personally but there are definitely a lot of
> > > > errors from pahole at the end. Arnaldo, is pahole not handling something
> > > > that it should with regards to clang's debug info?
> 
> > > Possibly, would it be possible to provide the vmlinux file where pahole
> > > is segfaulting when trying to encode BTF from DWARF?
> 
> > > These two files:
> 
> > > vmlinux drivers/misc/eeprom/at24.ko
> 
> > > So that I can run:
> > > LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko
>  
> > Sure, here you go:
>  
> > https://1drv.ms/u/s!AsQNYeB-IEbqqAilUuGHOU8BMLbf
>  
> > If you need more objects, just let me know. That series of commands in
> > the previous email should also get them for you locally if you need all
> > of them or want to investigate more.
> 
> llvm-dwarfdump is the only that is managing to process this file on a
> fedora:39 system, more work needed to figure out if this is something
> elfutils is planning to support, what amount of work would be necessary,
> etc.
> 
> Mark, do you know about work on elfutils to support:
> 
> ⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-dwarfdump at24.ko | head -22
> at24.ko:        file format elf32-hexagon

That seems to identify itself as an EM_QDSP6 (QUALCOMM DSP6) 32bit ELF
file. Neither binutils not elfutils seems to know how to resolve
EM_QDSP6 specific relocations. Normally that wouldn't be necessary,
but sadly kernel modules are still ET_REL files, so eu-readelf/readelf
needs relocations resolved to process the DWARF .debug sections.

This seems to need Qualcomm to upstream support for this processor
type to bintuils and elfutils.

Cheers,

Mark

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Nick Desaulniers]

On Tue, Jan 2, 2024 at 9:53 AM Mark Wielaard <mark@klomp.org> wrote:
>
> This seems to need Qualcomm to upstream support for this processor
> type to bintuils and elfutils.

Probably should disable BTF for hexagon until then.
-- 
Thanks,
~Nick Desaulniers

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Kent Overstreet]

On Wed, Jan 03, 2024 at 08:20:10AM -0800, Nick Desaulniers wrote:
> On Tue, Jan 2, 2024 at 9:53 AM Mark Wielaard <mark@klomp.org> wrote:
> >
> > This seems to need Qualcomm to upstream support for this processor
> > type to bintuils and elfutils.
> 
> Probably should disable BTF for hexagon until then.

Do we want to include a patch for that in the header cleanup tree?

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eeprom/at24.ko

[Nathan Chancellor]

On Wed, Jan 03, 2024 at 05:03:17PM -0500, Kent Overstreet wrote:
> On Wed, Jan 03, 2024 at 08:20:10AM -0800, Nick Desaulniers wrote:
> > On Tue, Jan 2, 2024 at 9:53 AM Mark Wielaard <mark@klomp.org> wrote:
> > >
> > > This seems to need Qualcomm to upstream support for this processor
> > > type to bintuils and elfutils.
> > 
> > Probably should disable BTF for hexagon until then.
> 
> Do we want to include a patch for that in the header cleanup tree?

This issue is reproducible on mainline so I don't think there needs to
be a patch for this in the header cleanup tree.

As for the patch, I assume it would look something like this?

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 4405f81248fb..1b939f5583eb 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -378,6 +378,8 @@ config DEBUG_INFO_BTF
 	depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST
 	depends on BPF_SYSCALL
 	depends on !DEBUG_INFO_DWARF5 || PAHOLE_VERSION >= 121
+	# pahole uses elfutils, which does not have support for Hexagon relocations
+	depends on !HEXAGON
 	help
 	  Generate deduplicated BTF type information from DWARF debug info.
 	  Turning this on expects presence of pahole tool, which will convert

RE: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eep...

[Brian Cain]

> -----Original Message-----
> From: Nathan Chancellor <nathan@kernel.org>
> Sent: Wednesday, January 3, 2024 5:56 PM
> To: Kent Overstreet <kent.overstreet@linux.dev>
> Cc: Nick Desaulniers <ndesaulniers@google.com>; Brian Cain
> <bcain@quicinc.com>; Arnaldo Carvalho de Melo <acme@kernel.org>; Yujie Liu
> <yujie.liu@intel.com>; kernel test robot <lkp@intel.com>; llvm@lists.linux.dev;
> oe-kbuild-all@lists.linux.dev; linux-hexagon@vger.kernel.org;
> dwarves@vger.kernel.org; Mark Wielaard <mark@klomp.org>
> Subject: Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420
> Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j
> --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --
> btf_gen_optimized --btf_base vmlinux drivers/misc/eep...
> 
> WARNING: This email originated from outside of Qualcomm. Please be wary of
> any links or attachments, and do not enable macros.
> 
> On Wed, Jan 03, 2024 at 05:03:17PM -0500, Kent Overstreet wrote:
> > On Wed, Jan 03, 2024 at 08:20:10AM -0800, Nick Desaulniers wrote:
> > > On Tue, Jan 2, 2024 at 9:53 AM Mark Wielaard <mark@klomp.org> wrote:
> > > >
> > > > This seems to need Qualcomm to upstream support for this processor
> > > > type to bintuils and elfutils.
> > >
> > > Probably should disable BTF for hexagon until then.
> >
> > Do we want to include a patch for that in the header cleanup tree?
> 
> This issue is reproducible on mainline so I don't think there needs to
> be a patch for this in the header cleanup tree.
> 
> As for the patch, I assume it would look something like this?
> 
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index 4405f81248fb..1b939f5583eb 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -378,6 +378,8 @@ config DEBUG_INFO_BTF
>         depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST
>         depends on BPF_SYSCALL
>         depends on !DEBUG_INFO_DWARF5 || PAHOLE_VERSION >= 121
> +       # pahole uses elfutils, which does not have support for Hexagon
> relocations
> +       depends on !HEXAGON
>         help
>           Generate deduplicated BTF type information from DWARF debug info.
>           Turning this on expects presence of pahole tool, which will convert

Acked-by: Brian Cain <bcain@quicinc.com>

RE: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eep...

[Brian Cain]

> -----Original Message-----
> From: Mark Wielaard <mark@klomp.org>
> Sent: Tuesday, January 2, 2024 11:54 AM
> To: Arnaldo Carvalho de Melo <acme@kernel.org>
> Cc: Nathan Chancellor <nathan@kernel.org>; Yujie Liu <yujie.liu@intel.com>;
> Nick Desaulniers <ndesaulniers@google.com>; Kent Overstreet
> <kent.overstreet@linux.dev>; kernel test robot <lkp@intel.com>;
> llvm@lists.linux.dev; oe-kbuild-all@lists.linux.dev; Brian Cain
> <bcain@quicinc.com>; linux-hexagon@vger.kernel.org;
> dwarves@vger.kernel.org
> Subject: Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420
> Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j
> --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --
> btf_gen_optimized --btf_base vmlinux drivers/misc/eep...
> 
> WARNING: This email originated from outside of Qualcomm. Please be wary of
> any links or attachments, and do not enable macros.
> 
> Hi Arnaldo,
> 
> On Tue, Jan 02, 2024 at 01:30:02PM -0300, Arnaldo Carvalho de Melo wrote:
> > Em Thu, Dec 28, 2023 at 10:34:04AM -0700, Nathan Chancellor escreveu:
> > > On Thu, Dec 28, 2023 at 11:21:06AM -0300, Arnaldo Carvalho de Melo
> wrote:
> > > > Em Wed, Dec 27, 2023 at 03:43:38PM -0700, Nathan Chancellor
> escreveu:
> > > > > I do not get a segfault personally but there are definitely a lot of
> > > > > errors from pahole at the end. Arnaldo, is pahole not handling
> something
> > > > > that it should with regards to clang's debug info?
> >
> > > > Possibly, would it be possible to provide the vmlinux file where pahole
> > > > is segfaulting when trying to encode BTF from DWARF?
> >
> > > > These two files:
> >
> > > > vmlinux drivers/misc/eeprom/at24.ko
> >
> > > > So that I can run:
> > > > LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --
> lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized
> --btf_base vmlinux drivers/misc/eeprom/at24.ko
> >
> > > Sure, here you go:
> >
> > > https://1drv.ms/u/s!AsQNYeB-IEbqqAilUuGHOU8BMLbf
> >
> > > If you need more objects, just let me know. That series of commands in
> > > the previous email should also get them for you locally if you need all
> > > of them or want to investigate more.
> >
> > llvm-dwarfdump is the only that is managing to process this file on a
> > fedora:39 system, more work needed to figure out if this is something
> > elfutils is planning to support, what amount of work would be necessary,
> > etc.
> >
> > Mark, do you know about work on elfutils to support:
> >
> > ⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-
> dwarfdump at24.ko | head -22
> > at24.ko:        file format elf32-hexagon
> 
> That seems to identify itself as an EM_QDSP6 (QUALCOMM DSP6) 32bit ELF
> file. Neither binutils not elfutils seems to know how to resolve
> EM_QDSP6 specific relocations. Normally that wouldn't be necessary,
> but sadly kernel modules are still ET_REL files, so eu-readelf/readelf
> needs relocations resolved to process the DWARF .debug sections.
> 
> This seems to need Qualcomm to upstream support for this processor
> type to bintuils and elfutils.

We can take a look at this.  But - please forgive my inexperience here -- do the corresponding tools such as llvm-readelf not suffice here?  Would it be welcome for us to change pahole to support those if it doesn't already?

-Brian

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eep...

[Arnaldo Carvalho de Melo]

Em Wed, Jan 03, 2024 at 05:25:11PM +0000, Brian Cain escreveu:
> > From: Mark Wielaard <mark@klomp.org>
> > To: Arnaldo Carvalho de Melo <acme@kernel.org>
> > > llvm-dwarfdump is the only that is managing to process this file on a
> > > fedora:39 system, more work needed to figure out if this is something
> > > elfutils is planning to support, what amount of work would be necessary,
> > > etc.

> > > Mark, do you know about work on elfutils to support:

> > > ⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-
> > dwarfdump at24.ko | head -22
> > > at24.ko:        file format elf32-hexagon

> > That seems to identify itself as an EM_QDSP6 (QUALCOMM DSP6) 32bit ELF
> > file. Neither binutils not elfutils seems to know how to resolve
> > EM_QDSP6 specific relocations. Normally that wouldn't be necessary,
> > but sadly kernel modules are still ET_REL files, so eu-readelf/readelf
> > needs relocations resolved to process the DWARF .debug sections.

> > This seems to need Qualcomm to upstream support for this processor
> > type to bintuils and elfutils.
 
> We can take a look at this.  But - please forgive my inexperience here
> -- do the corresponding tools such as llvm-readelf not suffice here?
> Would it be welcome for us to change pahole to support those if it
> doesn't already?

pahole uses the DWARF library that comes with elfutils, so the changes
that were made to the DWARF library used by llvm-readelf would have to
be done to elfutils' DWARF library for pahole to be able to process
these files.

IANAL to say if you can copy code across these these codebases.

- Arnaldo

Re: [bcachefs:header_cleanup 21/51] /bin/bash: line 1: 19420 Segmentation fault LLVM_OBJCOPY="llvm-objcopy" pahole -J --btf_gen_floats -j --lang_exclude=rust --skip_encoding_btf_inconsistent_proto --btf_gen_optimized --btf_base vmlinux drivers/misc/eep...

[Mark Wielaard]

Hi,

On Wed, 2024-01-03 at 17:45 -0300, Arnaldo Carvalho de Melo wrote:
> Em Wed, Jan 03, 2024 at 05:25:11PM +0000, Brian Cain escreveu:
> > > From: Mark Wielaard <mark@klomp.org>
> > > To: Arnaldo Carvalho de Melo <acme@kernel.org>
> > > 
> > > > Mark, do you know about work on elfutils to support:
> 
> > > > ⬢[acme@toolbox hexagon-randconfig-r005-20220913-pahole-crash]$ llvm-
> > > dwarfdump at24.ko | head -22
> > > > at24.ko:        file format elf32-hexagon
> 
> > > That seems to identify itself as an EM_QDSP6 (QUALCOMM DSP6) 32bit ELF
> > > file. Neither binutils not elfutils seems to know how to resolve
> > > EM_QDSP6 specific relocations. Normally that wouldn't be necessary,
> > > but sadly kernel modules are still ET_REL files, so eu-readelf/readelf
> > > needs relocations resolved to process the DWARF .debug sections.
> 
> > > This seems to need Qualcomm to upstream support for this processor
> > > type to bintuils and elfutils.
>  
> > We can take a look at this.  But - please forgive my inexperience here
> > -- do the corresponding tools such as llvm-readelf not suffice here?
> > Would it be welcome for us to change pahole to support those if it
> > doesn't already?
> 
> pahole uses the DWARF library that comes with elfutils, so the changes
> that were made to the DWARF library used by llvm-readelf would have to
> be done to elfutils' DWARF library for pahole to be able to process
> these files.
> 
> IANAL to say if you can copy code across these these codebases.

Literally copying code over between those codebases is probably not
going to work anyway. But it shouldn't be too hard to get just the
support for handling ET_REL kernel modules in elfutils.

Basically you'll have to add a new backend and at least implement the
reloc_simple_type callback (this is the one that tells elfutils which
relocations are "simple" and how they can be resolved between .debug
sections). An example to follow might be the initial LoongArch backend
support:
https://sourceware.org/cgit/elfutils/commit?id=13a4d1279c5b7847049ca3045d04f2705c45ce31
This one is just ~200 lines long, and the reloc_simple_types callback
is bigger than most, often arches have just really simple relocations
without any need for add/sub support. e.g the aarch backend simply has
support for 16, 32 and 64 offsets without any additional addsub addend:

/* Check for the simple reloc types.  */
Elf_Type
aarch64_reloc_simple_type (Ebl *ebl __attribute__ ((unused)), int type,
                           int *addsub __attribute__ ((unused))) 
{
  switch (type)
    {
    case R_AARCH64_ABS64:
      return ELF_T_XWORD;
    case R_AARCH64_ABS32:
      return ELF_T_WORD;
    case R_AARCH64_ABS16:
      return ELF_T_HALF;
    
    default:
      return ELF_T_NUM;
    }
}

The only relocations that are really relevant here are those that are
used for the .debug sections.

Then follow the CONTRIBUTING guide to submit the new (partial) port:
https://sourceware.org/cgit/elfutils/tree/CONTRIBUTING

Cheers,

Mark