Re: [PATCH v4 0/2] riscv: Add remaining module relocations and tests

[Charlie Jenkins <charlie@rivosinc.com>]

On Wed, Oct 18, 2023 at 12:35:55PM +0100, Conor Dooley wrote:
> Hey Charlie,
> 
> On Tue, Oct 17, 2023 at 10:34:15PM -0700, Charlie Jenkins wrote:
> > A handful of module relocations were missing, this patch includes the
> > remaining ones. I also wrote some test cases to ensure that module
> > loading works properly. Some relocations cannot be supported in the
> > kernel, these include the ones that rely on thread local storage and
> > dynamic linking.
> > 
> > ULEB128 handling is a bit special because SET and SUB relocations must
> > happen together, and SET must happen before SUB. A psABI proposal [1]
> > mandates that the first SET_ULEB128 that appears before a SUB_ULEB128
> > is the associated SET_ULEB128.
> > 
> > This can be tested by enabling KUNIT, RUNTIME_KERNEL_TESTING_MENU, and
> > RISCV_MODULE_LINKING_KUNIT.
> > 
> > [1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/403
> > 
> > Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
> > ---
> > Changes in v4:
> > - Complete removal of R_RISCV_RVC_LUI
> > - Fix bug in R_RISCV_SUB6 linking
> > - Only build ULEB128 tests if supported by toolchain
> > - Link to v3: https://lore.kernel.org/r/20231016-module_relocations-v3-0-a667fd6071e9@rivosinc.com
> 
> On patch 2/2:
> 
> ../arch/riscv/kernel/tests/module_test/test_uleb128.S:18:17: error: unknown relocation name
> ../arch/riscv/kernel/tests/module_test/test_uleb128.S:19:17: error: unknown relocation name
> 
> Same toolchain configuration in the patchwork automation as before.
> 
> Cheers,
> Conor.

Where do you see this error? On Patchwork I see a success [1].

[1] https://patchwork.kernel.org/project/linux-riscv/patch/20231017-module_relocations-v4-2-937f5ef316f0@rivosinc.com/

> 
> > 
> > Changes in v3:
> > - Add prototypes to test_module_linking_main as recommended by intel
> >   zero day bot
> > - Improve efficiency of ULEB128 pair matching
> > - Link to v2: https://lore.kernel.org/r/20231006-module_relocations-v2-0-47566453fedc@rivosinc.com
> > 
> > Changes in v2:
> > - Added ULEB128 relocations
> > - Link to v1: https://lore.kernel.org/r/20230913-module_relocations-v1-0-bb3d8467e793@rivosinc.com
> > 
> > ---
> > Charlie Jenkins (2):
> >       riscv: Add remaining module relocations
> >       riscv: Add tests for riscv module loading
> > 
> >  arch/riscv/Kconfig.debug                           |   1 +
> >  arch/riscv/include/uapi/asm/elf.h                  |   5 +-
> >  arch/riscv/kernel/Makefile                         |   1 +
> >  arch/riscv/kernel/module.c                         | 207 ++++++++++++++++++---
> >  arch/riscv/kernel/tests/Kconfig.debug              |  35 ++++
> >  arch/riscv/kernel/tests/Makefile                   |   1 +
> >  arch/riscv/kernel/tests/module_test/Makefile       |  15 ++
> >  .../tests/module_test/test_module_linking_main.c   |  85 +++++++++
> >  arch/riscv/kernel/tests/module_test/test_set16.S   |  23 +++
> >  arch/riscv/kernel/tests/module_test/test_set32.S   |  20 ++
> >  arch/riscv/kernel/tests/module_test/test_set6.S    |  23 +++
> >  arch/riscv/kernel/tests/module_test/test_set8.S    |  23 +++
> >  arch/riscv/kernel/tests/module_test/test_sub16.S   |  22 +++
> >  arch/riscv/kernel/tests/module_test/test_sub32.S   |  22 +++
> >  arch/riscv/kernel/tests/module_test/test_sub6.S    |  22 +++
> >  arch/riscv/kernel/tests/module_test/test_sub64.S   |  27 +++
> >  arch/riscv/kernel/tests/module_test/test_sub8.S    |  22 +++
> >  arch/riscv/kernel/tests/module_test/test_uleb128.S |  20 ++
> >  18 files changed, 548 insertions(+), 26 deletions(-)
> > ---
> > base-commit: 4d320c2d9a2b22f53523a1b012cda17a50220965
> > change-id: 20230908-module_relocations-f63ced651bd7
> > -- 
> > - Charlie
> >