lld is now able to build ARMv4 and ARMv4T kernels, which means it can
generate thunks for those (__ARMv4PILongThunk_*, __ARMv4PILongBXThunk_*)
that can interfere with kallsyms table generation since they do not get
ignore like the corresponding ARMv5+ ones are:

Inconsistent kallsyms data
Try "make KALLSYMS_EXTRA_PASS=1" as a workaround

Replace the hardcoded list of thunk symbols with a more general regex that
covers this one along with future symbols that follow the same pattern.

Fixes: 5eb6e280432d ("ARM: 9289/1: Allow pre-ARMv5 builds with ld.lld 16.0.0 and newer")
Fixes: efe6e3068067 ("kallsyms: fix nonconverging kallsyms table with lld")
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

get_line() does not trim the leading spaces, but the
parse_source_files() expects to get lines with source files paths where
the first space occurs after the file path.

Fixes: 70f30cfe5b89 ("modpost: use read_text_file() and get_line() for reading text files")
Signed-off-by: Radek Krejci <radek.krejci@oracle.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

With python 3.12, '\#' results in this warning
    SyntaxWarning: invalid escape sequence '\#'

Signed-off-by: Andrew Ballance <andrewjballance@gmail.com>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Commit 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
changed the ELF type of .btf.vmlinux.bin.o to ET_REL via dd, which works
fine for little endian platforms:

   00000000  7f 45 4c 46 02 01 01 00  00 00 00 00 00 00 00 00  |.ELF............|
  -00000010  03 00 b7 00 01 00 00 00  00 00 00 80 00 80 ff ff  |................|
  +00000010  01 00 b7 00 01 00 00 00  00 00 00 80 00 80 ff ff  |................|

However, for big endian platforms, it changes the wrong byte, resulting
in an invalid ELF file type, which ld.lld rejects:

   00000000  7f 45 4c 46 02 02 01 00  00 00 00 00 00 00 00 00  |.ELF............|
  -00000010  00 03 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|
  +00000010  01 03 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|

  Type:                              <unknown>: 103

  ld.lld: error: .btf.vmlinux.bin.o: unknown file type

Fix this by updating the entire 16-bit e_type field rather than just a
single byte, so that everything works correctly for all platforms and
linkers.

   00000000  7f 45 4c 46 02 02 01 00  00 00 00 00 00 00 00 00  |.ELF............|
  -00000010  00 03 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|
  +00000010  00 01 00 16 00 00 00 01  00 00 00 00 00 10 00 00  |................|

  Type:                              REL (Relocatable file)

While in the area, update the comment to mention that binutils 2.35+
matches LLD's behavior of rejecting an ET_EXEC input, which occurred
after the comment was added.

Cc: stable@vger.kernel.org
Fixes: 90ceddcb4950 ("bpf: Support llvm-objcopy for vmlinux BTF")
Link: https://github.com/llvm/llvm-project/pull/75643
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Pull Kbuild fixes from Masahiro Yamada:

 - Fix UML build with clang-18 and newer

 - Avoid using the alias attribute in host programs

 - Replace tabs with spaces when followed by conditionals for future GNU
   Make versions

 - Fix rpm-pkg for the systemd-provided kernel-install tool

 - Fix the undefined behavior in Kconfig for a 'int' symbol used in a
   conditional

* tag 'kbuild-fixes-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: initialize sym->curr.tri to 'no' for all symbol types again
  kbuild: rpm-pkg: simplify installkernel %post
  kbuild: Replace tabs with spaces when followed by conditionals
  modpost: avoid using the alias attribute
  kbuild: fix W= flags in the help message
  modpost: Add '.ltext' and '.ltext.*' to TEXT_SECTIONS
  um: Fix adding '-no-pie' for clang
  kbuild: defconf: use SRCARCH to find merged configs

Geert Uytterhoeven reported that commit 4e244c10eab3 ("kconfig: remove
unneeded symbol_empty variable") changed the default value of
CONFIG_LOG_CPU_MAX_BUF_SHIFT from 12 to 0.

As it turned out, this is an undefined behavior because sym_calc_value()
stopped setting the sym->curr.tri field for 'int', 'hex', and 'string'
symbols.

This commit restores the original behavior, where 'int', 'hex', 'string'
symbols are interpreted as false if used in boolean contexts.

CONFIG_LOG_CPU_MAX_BUF_SHIFT will default to 12 again, irrespective
of CONFIG_BASE_SMALL. Presumably, this is not the intended behavior,
as already reported [1], but this is another issue that should be
addressed by a separate patch.

[1]: https://lore.kernel.org/all/f6856be8-54b7-0fa0-1d17-39632bf29ada@oracle.com/

Fixes: 4e244c10eab3 ("kconfig: remove unneeded symbol_empty variable")
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Closes: https://lore.kernel.org/all/CAMuHMdWm6u1wX7efZQf=2XUAHascps76YQac6rdnQGhc8nop_Q@mail.gmail.com/
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The new installkernel application that is now included in systemd-udev
package allows installation although destination files are already present
in the boot directory of the kernel package, but is failing with the
implemented workaround for the old installkernel application from grubby
package.

For the new installkernel application, as Davide says:
<<The %post currently does a shuffling dance before calling installkernel.
This isn't actually necessary afaict, and the current implementation
ends up triggering downstream issues such as
https://github.com/systemd/systemd/issues/29568
This commit simplifies the logic to remove the shuffling. For reference,
the original logic was added in commit 3c9c7a14b627("rpm-pkg: add %post
section to create initramfs and grub hooks").>>

But we need to keep the old behavior as well, because the old installkernel
application from grubby package, does not allow this simplification and
we need to be backward compatible to avoid issues with the different
packages.

Mimic Fedora shipping process and store vmlinuz, config amd System.map
in the module directory instead of the boot directory. In this way, we will
avoid the commented problem for all the cases, because the new destination
files are not going to exist in the boot directory of the kernel package.

Replace installkernel tool with kernel-install tool, because the latter is
more complete.

Besides, after installkernel tool execution, check to complete if the
correct package files vmlinuz, System.map and config files are present
in /boot directory, and if necessary, copy manually for install operation.
In this way, take into account if  files were not previously copied from
/usr/lib/kernel/install.d/* scripts and if the suitable files for the
requested package are present (it could be others if the rpm files were
replace with a new pacakge with the same release and a different build).

Tested with Fedora 38, Fedora 39, RHEL 9, Oracle Linux 9.3,
openSUSE Tumbleweed and openMandrive ROME, using dnf/zypper and rpm tools.

cc: stable@vger.kernel.org
Co-Developed-by: Davide Cavalca <dcavalca@meta.com>
Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Aiden Leong reported modpost fails to build on macOS since commit
16a473f60edc ("modpost: inform compilers that fatal() never returns"):

  scripts/mod/modpost.c:93:21: error: aliases are not supported on darwin

Nathan's research indicates that Darwin seems to support weak aliases
at least [1]. Although the situation might be improved in future Clang
versions, we can achieve a similar outcome without relying on it.

This commit makes fatal() a macro of error() + exit(1) in modpost.h, as
compilers recognize that exit() never returns.

[1]: https://github.com/llvm/llvm-project/issues/71001

Fixes: 16a473f60edc ("modpost: inform compilers that fatal() never returns")
Reported-by: Aiden Leong <aiden.leong@aibsd.com>
Closes: https://lore.kernel.org/all/d9ac2960-6644-4a87-b5e4-4bfb6e0364a8@aibsd.com/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

After the linked LLVM change, building ARCH=um defconfig results in a
segmentation fault in modpost. Prior to commit a23e7584ecf3 ("modpost:
unify 'sym' and 'to' in default_mismatch_handler()"), there was a
warning:

  WARNING: modpost: vmlinux.o(__ex_table+0x88): Section mismatch in reference to the .ltext:(unknown)
  WARNING: modpost: The relocation at __ex_table+0x88 references
  section ".ltext" which is not in the list of
  authorized sections.  If you're adding a new section
  and/or if this reference is valid, add ".ltext" to the
  list of authorized sections to jump to on fault.
  This can be achieved by adding ".ltext" to
  OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.

The linked LLVM change moves global objects to the '.ltext' (and
'.ltext.*' with '-ffunction-sections') sections with '-mcmodel=large',
which ARCH=um uses. These sections should be handled just as '.text'
and '.text.*' are, so add them to TEXT_SECTIONS.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1981
Link: https://github.com/llvm/llvm-project/commit/4bf8a688956a759b7b6b8d94f42d25c13c7af130
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

For some ARCH values, SRCARCH, which should be used for finding arch/
subdirectory, is different from ARCH.

Signed-off-by: Zhang Bingwu <xtexchooser@duck.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>