[PATCH v4 0/4] x86/boot/compressed: Enable -Wunused and remove unused variables

[Thorsten Blum <blum@kernel.org>]

This series marks potentially unused variables and functions as
__maybe_unused and removes truly unused ones. Patch 4 enables -Wunused,
matching the W=0 kernel defaults. With WERROR=y, the warnings failed as
follows:

  arch/x86/boot/compressed/acpi.c:25:1: error: '__efi_get_rsdp_addr' defined but not used
  arch/x86/boot/compressed/acpi.c:29:6: error: unused variable 'ret'
  arch/x86/boot/compressed/acpi.c:57:15: error: unused variable 'nr_tables'
  arch/x86/boot/compressed/efi.c:64:16: error: unused variable 'et'
  arch/x86/boot/compressed/efi.c:136:6: error: unused variable 'ret'
  arch/x86/boot/compressed/kaslr.c:600:13: error: unused variable 'i'

Patch 2 also drops a redundant efi_get_system_table() call and uses the
existing efi_get_conf_table() error path.

Changes in v4:
- Add a newline to the log message in efi_get_system_table() (Jan)
- Make efi_get_system_table() static and update misc.h (Jan)
- v3: https://lore.kernel.org/r/20261109005528.3477-6-blum@kernel.org/

Changes in v3:
- Rebase patch 4/4
- v2: https://lore.kernel.org/r/20260624120300.590233-6-thorsten.blum@linux.dev/

Changes in v2:
- Fix a kernel test robot issue by marking __efi_get_rsdp_addr() as
  __maybe_unused: https://lore.kernel.org/r/202606240416.cXegPpiJ-lkp@intel.com/
- v1: https://lore.kernel.org/r/20260621144116.224010-6-thorsten.blum@linux.dev/

Thorsten Blum (4):
  x86/boot/compressed: Remove unused variables in EFI helpers
  x86/boot/compressed: Clean up EFI RSDP lookup in efi_get_rsdp_addr()
  x86/boot/compressed: Mark process_mem_region() index __maybe_unused
  x86/boot/compressed: Enable -Wunused

 arch/x86/boot/compressed/Makefile |  3 +++
 arch/x86/boot/compressed/acpi.c   | 18 ++++--------------
 arch/x86/boot/compressed/efi.c    | 21 +++++++--------------
 arch/x86/boot/compressed/kaslr.c  |  3 ++-
 arch/x86/boot/compressed/misc.h   |  6 ------
 5 files changed, 16 insertions(+), 35 deletions(-)