mbox series

[RFC,v1,00/23] LoongArch: Add objtool and ORC unwinder support

Message ID 1687247209-31676-1-git-send-email-tangyouling@loongson.cn
Headers
Series LoongArch: Add objtool and ORC unwinder support |

Message

Youling Tang June 20, 2023, 7:46 a.m. UTC 
  This series of patches adds objtool and ORC unwinder support for
LoongArch.

Patch 01 - 07 are from "Madhavan T. Venkataraman" [1] with minor
code tweaks. The "objtool: Reorganize ORC types" patch was not
added, because LoongArch cannot share `strcut orc_entry`, it also
needs to include ra_offset and ra_reg.

Since the changes in Patch 01 - 08 in [1] are architecture-independent,
it might be better if they could be separated separately from the series
of patches.

ORC unwinder can get a reliable stack trace, which provides a prerequisite
for the subsequent addition of livepatch support.


Instruction decoder
===================

To do this, an instruction decoder needs to be implemented. I have implemented
a simple, table-driven decoder for LoongArch. Only a subset of the instructions
needs to be fully decoded for this purpose:

	- Load-Store instructions
	- Add instructions
	- Branch instructions
	- Call instructions
	- Return instructions
	- Stack pointer authentication instruction


Unwind hints
============

Unwind hints are collected in a special section. Objtool converts unwind hints
to ORC data. The unwinder processes unwind hints to handle special cases
mentioned above.


ORC unwinder
============

Before vmlinux created, we check all metadata, find the stack operation,
note stack state and create orc data. Objtool insert two sections into
vmlinux. '.orc_unwind_ip' and '.orc_unwind'. (For modules, insert
'.rela.orc_unwind_ip' to relocate '.orc_unwind_ip'.) Each insn has only
one stack state in .orc_unwind and orc_unwind_ip hint its pc address.
Through unwinding orc data, we can get stack info both kernel and module.


This is a series of RFC patches, which may require long-term discussions
and revisions. It is not based on the latest code but based on 6.3-rc3.
Any ideas or suggestions are welcome.

base-commit: e8d018dd0257f744ca50a729e3d042cf2ec9da65 (Linux 6.3-rc3)

Link:
[1]: https://lore.kernel.org/lkml/20230202074036.507249-1-madvenka@linux.microsoft.com/#r

Madhavan T. Venkataraman (7):
  objtool: Reorganize CFI code
  objtool: Reorganize instruction-related code
  objtool: Move decode_instructions() to a separate file
  objtool: Reorganize Unwind hint code
  objtool: Reorganize ORC code
  objtool: Reorganize ORC kernel code
  objtool: Introduce STATIC_CHECK

Youling Tang (16):
  tools: LoongArch: Copy inst.h and asm.h to tools
  objtool: LoongArch: Add base definition for LoongArch
  objtool: LoongArch: Implement decoder
  objtool: Add annotate_reachable() for objtools
  LoongArch: bug: Add reachable annotation to warning macros
  objtool: Add next member in struct reloc
  objtool: Add orc_print_dump() package
  objtool: Add ORC support for LoongArch
  LoongArch: Add ORC unwinder support
  LoongArch: Support R_LARCH_32_PCREL relocation type in kernel module
  LoongArch: Fix fpu.S objtool warning
  LoongArch: Annotate unwind_hint
  LoongArch: Move some data definitions into the .data section
  objtool: Add arch-specific "noreturn" function handling
  objtool: Make update_cfi_state() arch-specific function
  LoongArch: objtool: Mark non-standard object files and directories

 arch/loongarch/Kconfig                        |   2 +
 arch/loongarch/Kconfig.debug                  |  11 +
 arch/loongarch/Makefile                       |   4 +
 arch/loongarch/include/asm/bug.h              |   1 +
 arch/loongarch/include/asm/module.h           |   7 +
 arch/loongarch/include/asm/orc_types.h        |  58 ++
 arch/loongarch/include/asm/stackframe.h       |   3 +
 arch/loongarch/include/asm/unwind.h           |  17 +-
 arch/loongarch/include/asm/unwind_hints.h     | 110 +++
 arch/loongarch/kernel/Makefile                |   3 +
 arch/loongarch/kernel/entry.S                 |   2 +
 arch/loongarch/kernel/fpu.S                   |  11 +-
 arch/loongarch/kernel/genex.S                 |   2 +
 arch/loongarch/kernel/head.S                  |   1 +
 arch/loongarch/kernel/module.c                |  21 +-
 arch/loongarch/kernel/relocate_kernel.S       |  12 +-
 arch/loongarch/kernel/setup.c                 |   2 +
 arch/loongarch/kernel/stacktrace.c            |   1 +
 arch/loongarch/kernel/unwind_orc.c            | 301 +++++++++
 arch/loongarch/kernel/vmlinux.lds.S           |   3 +
 arch/loongarch/power/Makefile                 |   2 +
 arch/loongarch/vdso/Makefile                  |   2 +
 arch/x86/include/asm/unwind.h                 |   5 -
 arch/x86/include/asm/unwind_hints.h           |  86 +++
 arch/x86/kernel/module.c                      |   7 +-
 arch/x86/kernel/unwind_orc.c                  | 268 +-------
 arch/x86/kernel/vmlinux.lds.S                 |   2 +-
 .../asm => include/asm-generic}/orc_lookup.h  |  43 ++
 include/linux/compiler.h                      |   9 +
 include/linux/objtool.h                       |  70 --
 kernel/Makefile                               |   2 +
 kernel/orc_lookup.c                           | 261 ++++++++
 scripts/Makefile                              |   5 +-
 tools/arch/loongarch/include/asm/asm.h        | 201 ++++++
 tools/arch/loongarch/include/asm/inst.h       | 629 ++++++++++++++++++
 tools/arch/loongarch/include/asm/orc_types.h  |  58 ++
 .../arch/loongarch/include/asm/unwind_hints.h | 110 +++
 tools/arch/x86/include/asm/unwind_hints.h     | 160 +++++
 tools/include/linux/bitops.h                  |  10 +
 tools/include/linux/objtool.h                 |  70 --
 tools/objtool/Build                           |   8 +-
 tools/objtool/Makefile                        |   9 +-
 tools/objtool/arch/loongarch/Build            |   3 +
 tools/objtool/arch/loongarch/decode.c         | 352 ++++++++++
 .../arch/loongarch/include/arch/cfi_regs.h    |  14 +
 .../objtool/arch/loongarch/include/arch/elf.h |  15 +
 .../arch/loongarch/include/arch/special.h     |  21 +
 tools/objtool/arch/loongarch/orc.c            | 155 +++++
 tools/objtool/arch/loongarch/special.c        |  25 +
 tools/objtool/arch/powerpc/special.c          |   3 +
 tools/objtool/arch/x86/Build                  |   1 +
 tools/objtool/arch/x86/include/arch/elf.h     |   1 +
 tools/objtool/arch/x86/orc.c                  | 164 +++++
 tools/objtool/arch/x86/special.c              |   4 +
 tools/objtool/cfi.c                           | 108 +++
 tools/objtool/check.c                         | 568 +---------------
 tools/objtool/decode.c                        | 136 ++++
 tools/objtool/elf.c                           |  11 +-
 tools/objtool/include/objtool/arch.h          |   3 +
 tools/objtool/include/objtool/cfi.h           |  12 +
 tools/objtool/include/objtool/check.h         |  97 +--
 tools/objtool/include/objtool/elf.h           |   1 +
 tools/objtool/include/objtool/insn.h          | 166 +++++
 tools/objtool/include/objtool/objtool.h       |   3 +
 tools/objtool/include/objtool/orc.h           |  15 +
 tools/objtool/include/objtool/special.h       |   3 +
 tools/objtool/insn.c                          | 195 ++++++
 tools/objtool/orc_dump.c                      |  67 +-
 tools/objtool/orc_gen.c                       |  79 +--
 tools/objtool/sync-check.sh                   |   9 +
 tools/objtool/unwind_hints.c                  | 107 +++
 71 files changed, 3721 insertions(+), 1206 deletions(-)
 create mode 100644 arch/loongarch/include/asm/orc_types.h
 create mode 100644 arch/loongarch/include/asm/unwind_hints.h
 create mode 100644 arch/loongarch/kernel/unwind_orc.c
 rename {arch/x86/include/asm => include/asm-generic}/orc_lookup.h (50%)
 create mode 100644 kernel/orc_lookup.c
 create mode 100644 tools/arch/loongarch/include/asm/asm.h
 create mode 100644 tools/arch/loongarch/include/asm/inst.h
 create mode 100644 tools/arch/loongarch/include/asm/orc_types.h
 create mode 100644 tools/arch/loongarch/include/asm/unwind_hints.h
 create mode 100644 tools/arch/x86/include/asm/unwind_hints.h
 create mode 100644 tools/objtool/arch/loongarch/Build
 create mode 100644 tools/objtool/arch/loongarch/decode.c
 create mode 100644 tools/objtool/arch/loongarch/include/arch/cfi_regs.h
 create mode 100644 tools/objtool/arch/loongarch/include/arch/elf.h
 create mode 100644 tools/objtool/arch/loongarch/include/arch/special.h
 create mode 100644 tools/objtool/arch/loongarch/orc.c
 create mode 100644 tools/objtool/arch/loongarch/special.c
 create mode 100644 tools/objtool/arch/x86/orc.c
 create mode 100644 tools/objtool/cfi.c
 create mode 100644 tools/objtool/decode.c
 create mode 100644 tools/objtool/include/objtool/insn.h
 create mode 100644 tools/objtool/include/objtool/orc.h
 create mode 100644 tools/objtool/insn.c
 create mode 100644 tools/objtool/unwind_hints.c

Comments

Xi Ruoyao June 20, 2023, 8:15 a.m. UTC | #1 
It looks like only 19 patches are successfully delivered, out of 23.

And AFAIK objtool needs libelf from elfutils, and the LoongArch support
in elfutils is not complete (there are about ten failures in the test
suite as at the latest 0.189 release).  Do we need to add more LoongArch
support into libelf and/or declare a minimal needed libelf version for
LoongArch objtool?

On Tue, 2023-06-20 at 15:46 +0800, Youling Tang wrote:
> This series of patches adds objtool and ORC unwinder support for
> LoongArch.
> 
> Patch 01 - 07 are from "Madhavan T. Venkataraman" [1] with minor
> code tweaks. The "objtool: Reorganize ORC types" patch was not
> added, because LoongArch cannot share `strcut orc_entry`, it also
> needs to include ra_offset and ra_reg.
> 
> Since the changes in Patch 01 - 08 in [1] are architecture-
> independent,
> it might be better if they could be separated separately from the
> series
> of patches.
> 
> ORC unwinder can get a reliable stack trace, which provides a
> prerequisite
> for the subsequent addition of livepatch support.
> 
> 
> Instruction decoder
> ===================
> 
> To do this, an instruction decoder needs to be implemented. I have
> implemented
> a simple, table-driven decoder for LoongArch. Only a subset of the
> instructions
> needs to be fully decoded for this purpose:
> 
>         - Load-Store instructions
>         - Add instructions
>         - Branch instructions
>         - Call instructions
>         - Return instructions
>         - Stack pointer authentication instruction
> 
> 
> Unwind hints
> ============
> 
> Unwind hints are collected in a special section. Objtool converts
> unwind hints
> to ORC data. The unwinder processes unwind hints to handle special
> cases
> mentioned above.
> 
> 
> ORC unwinder
> ============
> 
> Before vmlinux created, we check all metadata, find the stack
> operation,
> note stack state and create orc data. Objtool insert two sections into
> vmlinux. '.orc_unwind_ip' and '.orc_unwind'. (For modules, insert
> '.rela.orc_unwind_ip' to relocate '.orc_unwind_ip'.) Each insn has
> only
> one stack state in .orc_unwind and orc_unwind_ip hint its pc address.
> Through unwinding orc data, we can get stack info both kernel and
> module.
> 
> 
> This is a series of RFC patches, which may require long-term
> discussions
> and revisions. It is not based on the latest code but based on 6.3-
> rc3.
> Any ideas or suggestions are welcome.
> 
> base-commit: e8d018dd0257f744ca50a729e3d042cf2ec9da65 (Linux 6.3-rc3)
> 
> Link:
> [1]:
> https://lore.kernel.org/lkml/20230202074036.507249-1-madvenka@linux.microsoft.com/#r
> 
> Madhavan T. Venkataraman (7):
>   objtool: Reorganize CFI code
>   objtool: Reorganize instruction-related code
>   objtool: Move decode_instructions() to a separate file
>   objtool: Reorganize Unwind hint code
>   objtool: Reorganize ORC code
>   objtool: Reorganize ORC kernel code
>   objtool: Introduce STATIC_CHECK
> 
> Youling Tang (16):
>   tools: LoongArch: Copy inst.h and asm.h to tools
>   objtool: LoongArch: Add base definition for LoongArch
>   objtool: LoongArch: Implement decoder
>   objtool: Add annotate_reachable() for objtools
>   LoongArch: bug: Add reachable annotation to warning macros
>   objtool: Add next member in struct reloc
>   objtool: Add orc_print_dump() package
>   objtool: Add ORC support for LoongArch
>   LoongArch: Add ORC unwinder support
>   LoongArch: Support R_LARCH_32_PCREL relocation type in kernel module
>   LoongArch: Fix fpu.S objtool warning
>   LoongArch: Annotate unwind_hint
>   LoongArch: Move some data definitions into the .data section
>   objtool: Add arch-specific "noreturn" function handling
>   objtool: Make update_cfi_state() arch-specific function
>   LoongArch: objtool: Mark non-standard object files and directories
> 
>  arch/loongarch/Kconfig                        |   2 +
>  arch/loongarch/Kconfig.debug                  |  11 +
>  arch/loongarch/Makefile                       |   4 +
>  arch/loongarch/include/asm/bug.h              |   1 +
>  arch/loongarch/include/asm/module.h           |   7 +
>  arch/loongarch/include/asm/orc_types.h        |  58 ++
>  arch/loongarch/include/asm/stackframe.h       |   3 +
>  arch/loongarch/include/asm/unwind.h           |  17 +-
>  arch/loongarch/include/asm/unwind_hints.h     | 110 +++
>  arch/loongarch/kernel/Makefile                |   3 +
>  arch/loongarch/kernel/entry.S                 |   2 +
>  arch/loongarch/kernel/fpu.S                   |  11 +-
>  arch/loongarch/kernel/genex.S                 |   2 +
>  arch/loongarch/kernel/head.S                  |   1 +
>  arch/loongarch/kernel/module.c                |  21 +-
>  arch/loongarch/kernel/relocate_kernel.S       |  12 +-
>  arch/loongarch/kernel/setup.c                 |   2 +
>  arch/loongarch/kernel/stacktrace.c            |   1 +
>  arch/loongarch/kernel/unwind_orc.c            | 301 +++++++++
>  arch/loongarch/kernel/vmlinux.lds.S           |   3 +
>  arch/loongarch/power/Makefile                 |   2 +
>  arch/loongarch/vdso/Makefile                  |   2 +
>  arch/x86/include/asm/unwind.h                 |   5 -
>  arch/x86/include/asm/unwind_hints.h           |  86 +++
>  arch/x86/kernel/module.c                      |   7 +-
>  arch/x86/kernel/unwind_orc.c                  | 268 +-------
>  arch/x86/kernel/vmlinux.lds.S                 |   2 +-
>  .../asm => include/asm-generic}/orc_lookup.h  |  43 ++
>  include/linux/compiler.h                      |   9 +
>  include/linux/objtool.h                       |  70 --
>  kernel/Makefile                               |   2 +
>  kernel/orc_lookup.c                           | 261 ++++++++
>  scripts/Makefile                              |   5 +-
>  tools/arch/loongarch/include/asm/asm.h        | 201 ++++++
>  tools/arch/loongarch/include/asm/inst.h       | 629
> ++++++++++++++++++
>  tools/arch/loongarch/include/asm/orc_types.h  |  58 ++
>  .../arch/loongarch/include/asm/unwind_hints.h | 110 +++
>  tools/arch/x86/include/asm/unwind_hints.h     | 160 +++++
>  tools/include/linux/bitops.h                  |  10 +
>  tools/include/linux/objtool.h                 |  70 --
>  tools/objtool/Build                           |   8 +-
>  tools/objtool/Makefile                        |   9 +-
>  tools/objtool/arch/loongarch/Build            |   3 +
>  tools/objtool/arch/loongarch/decode.c         | 352 ++++++++++
>  .../arch/loongarch/include/arch/cfi_regs.h    |  14 +
>  .../objtool/arch/loongarch/include/arch/elf.h |  15 +
>  .../arch/loongarch/include/arch/special.h     |  21 +
>  tools/objtool/arch/loongarch/orc.c            | 155 +++++
>  tools/objtool/arch/loongarch/special.c        |  25 +
>  tools/objtool/arch/powerpc/special.c          |   3 +
>  tools/objtool/arch/x86/Build                  |   1 +
>  tools/objtool/arch/x86/include/arch/elf.h     |   1 +
>  tools/objtool/arch/x86/orc.c                  | 164 +++++
>  tools/objtool/arch/x86/special.c              |   4 +
>  tools/objtool/cfi.c                           | 108 +++
>  tools/objtool/check.c                         | 568 +---------------
>  tools/objtool/decode.c                        | 136 ++++
>  tools/objtool/elf.c                           |  11 +-
>  tools/objtool/include/objtool/arch.h          |   3 +
>  tools/objtool/include/objtool/cfi.h           |  12 +
>  tools/objtool/include/objtool/check.h         |  97 +--
>  tools/objtool/include/objtool/elf.h           |   1 +
>  tools/objtool/include/objtool/insn.h          | 166 +++++
>  tools/objtool/include/objtool/objtool.h       |   3 +
>  tools/objtool/include/objtool/orc.h           |  15 +
>  tools/objtool/include/objtool/special.h       |   3 +
>  tools/objtool/insn.c                          | 195 ++++++
>  tools/objtool/orc_dump.c                      |  67 +-
>  tools/objtool/orc_gen.c                       |  79 +--
>  tools/objtool/sync-check.sh                   |   9 +
>  tools/objtool/unwind_hints.c                  | 107 +++
>  71 files changed, 3721 insertions(+), 1206 deletions(-)
>  create mode 100644 arch/loongarch/include/asm/orc_types.h
>  create mode 100644 arch/loongarch/include/asm/unwind_hints.h
>  create mode 100644 arch/loongarch/kernel/unwind_orc.c
>  rename {arch/x86/include/asm => include/asm-generic}/orc_lookup.h
> (50%)
>  create mode 100644 kernel/orc_lookup.c
>  create mode 100644 tools/arch/loongarch/include/asm/asm.h
>  create mode 100644 tools/arch/loongarch/include/asm/inst.h
>  create mode 100644 tools/arch/loongarch/include/asm/orc_types.h
>  create mode 100644 tools/arch/loongarch/include/asm/unwind_hints.h
>  create mode 100644 tools/arch/x86/include/asm/unwind_hints.h
>  create mode 100644 tools/objtool/arch/loongarch/Build
>  create mode 100644 tools/objtool/arch/loongarch/decode.c
>  create mode 100644
> tools/objtool/arch/loongarch/include/arch/cfi_regs.h
>  create mode 100644 tools/objtool/arch/loongarch/include/arch/elf.h
>  create mode 100644
> tools/objtool/arch/loongarch/include/arch/special.h
>  create mode 100644 tools/objtool/arch/loongarch/orc.c
>  create mode 100644 tools/objtool/arch/loongarch/special.c
>  create mode 100644 tools/objtool/arch/x86/orc.c
>  create mode 100644 tools/objtool/cfi.c
>  create mode 100644 tools/objtool/decode.c
>  create mode 100644 tools/objtool/include/objtool/insn.h
>  create mode 100644 tools/objtool/include/objtool/orc.h
>  create mode 100644 tools/objtool/insn.c
>  create mode 100644 tools/objtool/unwind_hints.c
>
Youling Tang June 20, 2023, 8:29 a.m. UTC | #2 
Hi, Ruoyao

On 06/20/2023 04:15 PM, Xi Ruoyao wrote:
> It looks like only 19 patches are successfully delivered, out of 23.
I'm sorry, somehow the patchset didn't reach the mailing list. Probably
due to the sending limit being reached.

>
> And AFAIK objtool needs libelf from elfutils, and the LoongArch support
> in elfutils is not complete (there are about ten failures in the test
> suite as at the latest 0.189 release).  Do we need to add more LoongArch
> support into libelf and/or declare a minimal needed libelf version for
> LoongArch objtool?
After the following series of patches [1], the elfutils test results
are passed.

[1]: https://sourceware.org/pipermail/elfutils-devel/2023q2/006107.html

Thanks,
Youling
>
> On Tue, 2023-06-20 at 15:46 +0800, Youling Tang wrote:
>> This series of patches adds objtool and ORC unwinder support for
>> LoongArch.
>>
>> Patch 01 - 07 are from "Madhavan T. Venkataraman" [1] with minor
>> code tweaks. The "objtool: Reorganize ORC types" patch was not
>> added, because LoongArch cannot share `strcut orc_entry`, it also
>> needs to include ra_offset and ra_reg.
>>
>> Since the changes in Patch 01 - 08 in [1] are architecture-
>> independent,
>> it might be better if they could be separated separately from the
>> series
>> of patches.
>>
>> ORC unwinder can get a reliable stack trace, which provides a
>> prerequisite
>> for the subsequent addition of livepatch support.
>>
>>
>> Instruction decoder
>> ===================
>>
>> To do this, an instruction decoder needs to be implemented. I have
>> implemented
>> a simple, table-driven decoder for LoongArch. Only a subset of the
>> instructions
>> needs to be fully decoded for this purpose:
>>
>>         - Load-Store instructions
>>         - Add instructions
>>         - Branch instructions
>>         - Call instructions
>>         - Return instructions
>>         - Stack pointer authentication instruction
>>
>>
>> Unwind hints
>> ============
>>
>> Unwind hints are collected in a special section. Objtool converts
>> unwind hints
>> to ORC data. The unwinder processes unwind hints to handle special
>> cases
>> mentioned above.
>>
>>
>> ORC unwinder
>> ============
>>
>> Before vmlinux created, we check all metadata, find the stack
>> operation,
>> note stack state and create orc data. Objtool insert two sections into
>> vmlinux. '.orc_unwind_ip' and '.orc_unwind'. (For modules, insert
>> '.rela.orc_unwind_ip' to relocate '.orc_unwind_ip'.) Each insn has
>> only
>> one stack state in .orc_unwind and orc_unwind_ip hint its pc address.
>> Through unwinding orc data, we can get stack info both kernel and
>> module.
>>
>>
>> This is a series of RFC patches, which may require long-term
>> discussions
>> and revisions. It is not based on the latest code but based on 6.3-
>> rc3.
>> Any ideas or suggestions are welcome.
>>
>> base-commit: e8d018dd0257f744ca50a729e3d042cf2ec9da65 (Linux 6.3-rc3)
>>
>> Link:
>> [1]:
>> https://lore.kernel.org/lkml/20230202074036.507249-1-madvenka@linux.microsoft.com/#r
>>
>> Madhavan T. Venkataraman (7):
>>   objtool: Reorganize CFI code
>>   objtool: Reorganize instruction-related code
>>   objtool: Move decode_instructions() to a separate file
>>   objtool: Reorganize Unwind hint code
>>   objtool: Reorganize ORC code
>>   objtool: Reorganize ORC kernel code
>>   objtool: Introduce STATIC_CHECK
>>
>> Youling Tang (16):
>>   tools: LoongArch: Copy inst.h and asm.h to tools
>>   objtool: LoongArch: Add base definition for LoongArch
>>   objtool: LoongArch: Implement decoder
>>   objtool: Add annotate_reachable() for objtools
>>   LoongArch: bug: Add reachable annotation to warning macros
>>   objtool: Add next member in struct reloc
>>   objtool: Add orc_print_dump() package
>>   objtool: Add ORC support for LoongArch
>>   LoongArch: Add ORC unwinder support
>>   LoongArch: Support R_LARCH_32_PCREL relocation type in kernel module
>>   LoongArch: Fix fpu.S objtool warning
>>   LoongArch: Annotate unwind_hint
>>   LoongArch: Move some data definitions into the .data section
>>   objtool: Add arch-specific "noreturn" function handling
>>   objtool: Make update_cfi_state() arch-specific function
>>   LoongArch: objtool: Mark non-standard object files and directories
>>
>>  arch/loongarch/Kconfig                        |   2 +
>>  arch/loongarch/Kconfig.debug                  |  11 +
>>  arch/loongarch/Makefile                       |   4 +
>>  arch/loongarch/include/asm/bug.h              |   1 +
>>  arch/loongarch/include/asm/module.h           |   7 +
>>  arch/loongarch/include/asm/orc_types.h        |  58 ++
>>  arch/loongarch/include/asm/stackframe.h       |   3 +
>>  arch/loongarch/include/asm/unwind.h           |  17 +-
>>  arch/loongarch/include/asm/unwind_hints.h     | 110 +++
>>  arch/loongarch/kernel/Makefile                |   3 +
>>  arch/loongarch/kernel/entry.S                 |   2 +
>>  arch/loongarch/kernel/fpu.S                   |  11 +-
>>  arch/loongarch/kernel/genex.S                 |   2 +
>>  arch/loongarch/kernel/head.S                  |   1 +
>>  arch/loongarch/kernel/module.c                |  21 +-
>>  arch/loongarch/kernel/relocate_kernel.S       |  12 +-
>>  arch/loongarch/kernel/setup.c                 |   2 +
>>  arch/loongarch/kernel/stacktrace.c            |   1 +
>>  arch/loongarch/kernel/unwind_orc.c            | 301 +++++++++
>>  arch/loongarch/kernel/vmlinux.lds.S           |   3 +
>>  arch/loongarch/power/Makefile                 |   2 +
>>  arch/loongarch/vdso/Makefile                  |   2 +
>>  arch/x86/include/asm/unwind.h                 |   5 -
>>  arch/x86/include/asm/unwind_hints.h           |  86 +++
>>  arch/x86/kernel/module.c                      |   7 +-
>>  arch/x86/kernel/unwind_orc.c                  | 268 +-------
>>  arch/x86/kernel/vmlinux.lds.S                 |   2 +-
>>  .../asm => include/asm-generic}/orc_lookup.h  |  43 ++
>>  include/linux/compiler.h                      |   9 +
>>  include/linux/objtool.h                       |  70 --
>>  kernel/Makefile                               |   2 +
>>  kernel/orc_lookup.c                           | 261 ++++++++
>>  scripts/Makefile                              |   5 +-
>>  tools/arch/loongarch/include/asm/asm.h        | 201 ++++++
>>  tools/arch/loongarch/include/asm/inst.h       | 629
>> ++++++++++++++++++
>>  tools/arch/loongarch/include/asm/orc_types.h  |  58 ++
>>  .../arch/loongarch/include/asm/unwind_hints.h | 110 +++
>>  tools/arch/x86/include/asm/unwind_hints.h     | 160 +++++
>>  tools/include/linux/bitops.h                  |  10 +
>>  tools/include/linux/objtool.h                 |  70 --
>>  tools/objtool/Build                           |   8 +-
>>  tools/objtool/Makefile                        |   9 +-
>>  tools/objtool/arch/loongarch/Build            |   3 +
>>  tools/objtool/arch/loongarch/decode.c         | 352 ++++++++++
>>  .../arch/loongarch/include/arch/cfi_regs.h    |  14 +
>>  .../objtool/arch/loongarch/include/arch/elf.h |  15 +
>>  .../arch/loongarch/include/arch/special.h     |  21 +
>>  tools/objtool/arch/loongarch/orc.c            | 155 +++++
>>  tools/objtool/arch/loongarch/special.c        |  25 +
>>  tools/objtool/arch/powerpc/special.c          |   3 +
>>  tools/objtool/arch/x86/Build                  |   1 +
>>  tools/objtool/arch/x86/include/arch/elf.h     |   1 +
>>  tools/objtool/arch/x86/orc.c                  | 164 +++++
>>  tools/objtool/arch/x86/special.c              |   4 +
>>  tools/objtool/cfi.c                           | 108 +++
>>  tools/objtool/check.c                         | 568 +---------------
>>  tools/objtool/decode.c                        | 136 ++++
>>  tools/objtool/elf.c                           |  11 +-
>>  tools/objtool/include/objtool/arch.h          |   3 +
>>  tools/objtool/include/objtool/cfi.h           |  12 +
>>  tools/objtool/include/objtool/check.h         |  97 +--
>>  tools/objtool/include/objtool/elf.h           |   1 +
>>  tools/objtool/include/objtool/insn.h          | 166 +++++
>>  tools/objtool/include/objtool/objtool.h       |   3 +
>>  tools/objtool/include/objtool/orc.h           |  15 +
>>  tools/objtool/include/objtool/special.h       |   3 +
>>  tools/objtool/insn.c                          | 195 ++++++
>>  tools/objtool/orc_dump.c                      |  67 +-
>>  tools/objtool/orc_gen.c                       |  79 +--
>>  tools/objtool/sync-check.sh                   |   9 +
>>  tools/objtool/unwind_hints.c                  | 107 +++
>>  71 files changed, 3721 insertions(+), 1206 deletions(-)
>>  create mode 100644 arch/loongarch/include/asm/orc_types.h
>>  create mode 100644 arch/loongarch/include/asm/unwind_hints.h
>>  create mode 100644 arch/loongarch/kernel/unwind_orc.c
>>  rename {arch/x86/include/asm => include/asm-generic}/orc_lookup.h
>> (50%)
>>  create mode 100644 kernel/orc_lookup.c
>>  create mode 100644 tools/arch/loongarch/include/asm/asm.h
>>  create mode 100644 tools/arch/loongarch/include/asm/inst.h
>>  create mode 100644 tools/arch/loongarch/include/asm/orc_types.h
>>  create mode 100644 tools/arch/loongarch/include/asm/unwind_hints.h
>>  create mode 100644 tools/arch/x86/include/asm/unwind_hints.h
>>  create mode 100644 tools/objtool/arch/loongarch/Build
>>  create mode 100644 tools/objtool/arch/loongarch/decode.c
>>  create mode 100644
>> tools/objtool/arch/loongarch/include/arch/cfi_regs.h
>>  create mode 100644 tools/objtool/arch/loongarch/include/arch/elf.h
>>  create mode 100644
>> tools/objtool/arch/loongarch/include/arch/special.h
>>  create mode 100644 tools/objtool/arch/loongarch/orc.c
>>  create mode 100644 tools/objtool/arch/loongarch/special.c
>>  create mode 100644 tools/objtool/arch/x86/orc.c
>>  create mode 100644 tools/objtool/cfi.c
>>  create mode 100644 tools/objtool/decode.c
>>  create mode 100644 tools/objtool/include/objtool/insn.h
>>  create mode 100644 tools/objtool/include/objtool/orc.h
>>  create mode 100644 tools/objtool/insn.c
>>  create mode 100644 tools/objtool/unwind_hints.c
>>
>
Xi Ruoyao June 20, 2023, 8:32 a.m. UTC | #3 
On Tue, 2023-06-20 at 16:29 +0800, Youling Tang wrote:
> Hi, Ruoyao
> 
> On 06/20/2023 04:15 PM, Xi Ruoyao wrote:
> > It looks like only 19 patches are successfully delivered, out of 23.
> I'm sorry, somehow the patchset didn't reach the mailing list. Probably
> due to the sending limit being reached.

They've reached now.  Thanks!

> > And AFAIK objtool needs libelf from elfutils, and the LoongArch support
> > in elfutils is not complete (there are about ten failures in the test
> > suite as at the latest 0.189 release).  Do we need to add more LoongArch
> > support into libelf and/or declare a minimal needed libelf version for
> > LoongArch objtool?

> After the following series of patches [1], the elfutils test results
> are passed.
> 
> [1]: https://sourceware.org/pipermail/elfutils-devel/2023q2/006107.html

Wow thanks, I'll add them into my build.  But I'm not sure if we need a
libelf version check or something in the kernel building system.
Peter Zijlstra June 20, 2023, 8:38 a.m. UTC | #4 
On Tue, Jun 20, 2023 at 04:29:12PM +0800, Youling Tang wrote:
> Hi, Ruoyao
> 
> On 06/20/2023 04:15 PM, Xi Ruoyao wrote:
> > It looks like only 19 patches are successfully delivered, out of 23.
> I'm sorry, somehow the patchset didn't reach the mailing list. Probably
> due to the sending limit being reached.

I got all the patches, but their threading is broken, they come in
chunks of 5 or :/
Peter Zijlstra June 20, 2023, 8:42 a.m. UTC | #5 
On Tue, Jun 20, 2023 at 03:46:26PM +0800, Youling Tang wrote:
> This series of patches adds objtool and ORC unwinder support for
> LoongArch.
> 
> Patch 01 - 07 are from "Madhavan T. Venkataraman" [1] with minor
> code tweaks. The "objtool: Reorganize ORC types" patch was not
> added, because LoongArch cannot share `strcut orc_entry`, it also
> needs to include ra_offset and ra_reg.

Yeah, I wish you would not have done that :-( I really don't like those
patches. I just don't much believe in that dynamic validation thing, and
doubly not for the patches you did pick not including any actual
rationale for it.


Also, the patches very much do not apply to tip/objtool/core,
specifically Josh recently reworked the reloc stuff quite dramatically.
Xi Ruoyao June 20, 2023, 8:48 a.m. UTC | #6 
On Tue, 2023-06-20 at 10:38 +0200, Peter Zijlstra wrote:
> On Tue, Jun 20, 2023 at 04:29:12PM +0800, Youling Tang wrote:
> > Hi, Ruoyao
> > 
> > On 06/20/2023 04:15 PM, Xi Ruoyao wrote:
> > > It looks like only 19 patches are successfully delivered, out of 23.
> > I'm sorry, somehow the patchset didn't reach the mailing list. Probably
> > due to the sending limit being reached.
> 
> I got all the patches, but their threading is broken, they come in
> chunks of 5 or :/

Youling: when you need to resend a part of the series next time, you can
use the "--in-reply-to=" option of git send-email to avoid such an
issue.  See the man page of git send-email for details :).
Youling Tang June 20, 2023, 8:49 a.m. UTC | #7 
Hi, Peter

On 06/20/2023 04:38 PM, Peter Zijlstra wrote:
> On Tue, Jun 20, 2023 at 04:29:12PM +0800, Youling Tang wrote:
>> Hi, Ruoyao
>>
>> On 06/20/2023 04:15 PM, Xi Ruoyao wrote:
>>> It looks like only 19 patches are successfully delivered, out of 23.
>> I'm sorry, somehow the patchset didn't reach the mailing list. Probably
>> due to the sending limit being reached.
>
> I got all the patches, but their threading is broken, they come in
> chunks of 5 or :/

Yes, due to the limitation of the mailbox, only 5 patches can be sent
at a time (the number of patches multiplied by the number of people
sent), so the thread was interrupted, which caused inconvenience to the
review code, I am very sorry.

Thanks,
Youling