lib/Kconfig.debug: disable CONFIG_DEBUG_INFO_BTF for Hexagon

pahole, which generates BTF, relies on elfutils to process DWARF debug
info.  Because kernel modules are relocatable files, elfutils needs to
resolve relocations when processing the DWARF .debug sections.

Hexagon is not supported in binutils or elfutils, so elfutils is unable to
process relocations in kernel modules, causing pahole to crash during BTF
generation.

Do not allow CONFIG_DEBUG_INFO_BTF to be selected for Hexagon until it is
supported in elfutils, so that there are no more cryptic build failures
during BTF generation.

Link: https://lkml.kernel.org/r/20240105-hexagon-disable-btf-v1-1-ddab073e7f74@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312192107.wMIKiZWw-lkp@intel.com/
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Brian Cain <bcain@quicinc.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 97ce28f4d1540482082bf9d5072c39bdd25627f1..ba25129563ad769ec84436af8b79cfbf3f265d97 100644 (file)
--- 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