next-20250422: arch/riscv/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported

[Naresh Kamboju]

Regressions on riscv tinyconfig and lkftconfig failed with clang-20
and gcc-13 on the Linux next-20250422 tag onwards.

The defconfig builds pass but tinyconfig and lkftconfig (compat and
VDSO) failed.

First seen on the next-20250422
 Good: next-20250417
 Bad:  next-20250422..next-20250423

Regressions found on riscv:
  - build/rv32-clang-20-tinyconfig
  - build/rv32-clang-20-tinyconfig
  - build/korg-clang-20-lkftconfig-hardening
  - build/gcc-13-lkftconfig

Regression Analysis:
 - New regression? Yes
 - Reproducibility? Yes

Build regression: riscv vdso.so.dbg dynamic relocations are not supported

Reported-by: Linux Kernel Functional Testing <lkft at linaro.org>

## Build log riscv
build errors with gcc
arch/riscv/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported
make[3]: *** [arch/riscv/kernel/vdso/Makefile:60:
arch/riscv/kernel/vdso/vdso.so.dbg] Error 1

build errors with clang
ld.lld: error: version script assignment of 'LINUX_4.15' to symbol
'__vdso_getrandom' failed: symbol not defined
llvm-nm: error: arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg: No
such file or directory
ld.lld: error: version script assignment of 'LINUX_4.15' to symbol
'__vdso_getrandom' failed: symbol not defined
llvm-objcopy: error:
'arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg': No such file or
directory
arch/riscv/kernel/compat_signal.c:220:28: error: use of undeclared
identifier 'compat__vdso_rt_sigreturn_offset'
  220 |         regs->ra = (unsigned long)COMPAT_VDSO_SYMBOL(
      |                                   ^
arch/riscv/include/asm/vdso.h:29:42: note: expanded from macro
'COMPAT_VDSO_SYMBOL'
   29 |         (void __user *)((unsigned long)(base) +
compat__vdso_##name##_offset)
      |                                                 ^
<scratch space>:317:1: note: expanded from here
  317 | compat__vdso_rt_sigreturn_offset
      | ^
1 error generated.


## Source
* Kernel version: 6.15.0-rc3
* Git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git
* Git sha: 2c9c612abeb38aab0e87d48496de6fd6daafb00b
* Git describe: next-20250422
* Project details:
https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20250422/
* Architectures: riscv
* Toolchains: clang-20, gcc-13
* Kconfigs: lkftconfig

## Build riscv
* Build log: https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20250422/testrun/28190346/suite/build/test/gcc-13-lkftconfig/log
* Build history:
https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20250422/testrun/28190346/suite/build/test/gcc-13-lkftconfig/history/
* Build details:
https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20250422/testrun/28190346/suite/build/test/gcc-13-lkftconfig/details/
* Build link: https://storage.tuxsuite.com/public/linaro/lkft/builds/2w5Fmeq3a09b3torxIis2kurhBY/
* Kernel config:
https://storage.tuxsuite.com/public/linaro/lkft/builds/2w5Fmeq3a09b3torxIis2kurhBY/config

## Steps to reproduce on riscv
 - tuxmake --runtime podman --target-arch riscv --toolchain clang-20
--kconfig tinyconfig --kconfig-add rv32_defconfig LLVM=1
 - tuxmake --runtime podman --target-arch riscv --toolchain gcc-13
--kconfig https://storage.tuxsuite.com/public/linaro/lkft/builds/2w5Fmeq3a09b3torxIis2kurhBY/config

--
Linaro LKFT
https://lkft.linaro.org