[ Upstream commit 1c4a7587d1bbee0fd53b63af60e4244a62775f57 ]

The section mismatch check prints a bogus symbol name on some
architectures.

[test code]

  #include <linux/init.h>

  int __initdata foo;
  int get_foo(void) { return foo; }

If you compile it with GCC for riscv or loongarch, modpost will show an
incorrect symbol name:

  WARNING: modpost: vmlinux: section mismatch in reference: get_foo+0x8 (section: .text) -> done (section: .init.data)

To get the correct symbol address, the st_value must be added.

This issue has never been noticed since commit 93684d3b8062 ("kbuild:
include symbol names in section mismatch warnings") presumably because
st_value becomes zero on most architectures when the referenced symbol
is looked up. It is not true for riscv or loongarch, at least.

With this fix, modpost will show the correct symbol name:

  WARNING: modpost: vmlinux: section mismatch in reference: get_foo+0x8 (section: .text) -> foo (section: .init.data)

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Drivers must not reference functions marked with __exit as these likely
are not available when the code is built-in.

There are few creative offenders uncovered for example in ARCH=amd64
allmodconfig builds. So only trigger the section mismatch warning for
W=1 builds.

The dual rule that drivers must not reference .init.* is implemented
since commit 0db252452378 ("modpost: don't allow *driver to reference
.init.*") which however missed that .exit.* should be handled in the
same way.

Thanks to Masahiro Yamada and Arnd Bergmann who gave valuable hints to
find this improvement.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Pull parisc architecture fixes from Helge Deller:

 - fix reference to exported symbols for parisc64 [Masahiro Yamada]

 - Block-TLB (BTLB) support on 32-bit CPUs

 - sparse and build-warning fixes

* tag 'parisc-for-6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  linux/export: fix reference to exported functions for parisc64
  parisc: BTLB: Initialize BTLB tables at CPU startup
  parisc: firmware: Simplify calling non-PA20 functions
  parisc: BTLB: _edata symbol has to be page aligned for BTLB support
  parisc: BTLB: Add BTLB insert and purge firmware function wrappers
  parisc: BTLB: Clear possibly existing BTLB entries
  parisc: Prepare for Block-TLB support on 32-bit kernel
  parisc: shmparam.h: Document aliasing requirements of PA-RISC
  parisc: irq: Make irq_stack_union static to avoid sparse warning
  parisc: drivers: Fix sparse warning
  parisc: iosapic.c: Fix sparse warnings
  parisc: ccio-dma: Fix sparse warnings
  parisc: sba-iommu: Fix sparse warnigs
  parisc: sba: Fix compile warning wrt list of SBA devices
  parisc: sba_iommu: Fix build warning if procfs if disabled

John David Anglin reported parisc has been broken since commit
ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by modpost").

Like ia64, parisc64 uses a function descriptor. The function
references must be prefixed with P%.

Also, symbols prefixed $$ from the library have the symbol type
STT_LOPROC instead of STT_FUNC. They should be handled as functions
too.

Fixes: ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by modpost")
Reported-by: John David Anglin <dave.anglin@bell.net>
Tested-by: John David Anglin <dave.anglin@bell.net>
Tested-by: Helge Deller <deller@gmx.de>
Closes: https://lore.kernel.org/linux-parisc/1901598a-e11d-f7dd-a5d9-9a69d06e6b6e@bell.net/T/#u
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>

.llvm.call-graph-profile section is added by clang when the kernel is
built with profiles (e.g. -fprofile-sample-use= or -fprofile-use=).
Note that .llvm.call-graph-profile intentionally uses REL relocations
to decrease the object size, for more details see
https://reviews.llvm.org/D104080.

The section contains edge information derived from text sections,
so .llvm.call-graph-profile itself doesn't need more analysis as
the text sections have been analyzed.

This change fixes the kernel build with clang and a sample profile
which currently fails with:

"FATAL: modpost: Please add code to calculate addend for this architecture"

Signed-off-by: Denis Nikitin <denik@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Remove the Elf_Rela variables used in the for-loop in section_rel().

This makes the code consistent; section_rel() only uses Elf_Rel,
section_rela() only uses Elf_Rela.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

MIPS64 little endian target has an odd encoding of r_info.

This commit makes the special handling less ugly. It is still ugly,
but #if conditionals will go away, at least.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

All of addend_*_rel() need the Elf_Rela pointer just for calculating
ELF_R_TYPE(r->r_info).

You can do it on the caller to de-duplicate the code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Now that none of addend_*_rel() returns a meaningful value (the return
value is always 0), change all of them to return the value of r_addend.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Currently, all files with EXPORT_SYMBOL() are rebuilt when CONFIG_MODULES
is flipped due to <linux/export.h> depending on CONFIG_MODULES.

Now that modpost can make a final decision about export symbols,
<linux/export.h> does not need to make EXPORT_SYMBOL() no-op.
Instead, modpost can skip emitting KSYMTAB when CONFIG_MODULES is unset.

This commit will reduce the number of recompilation when CONFIG_MODULES
is toggled.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>