538 Commits
Author SHA1 Message Date
Masahiro Yamada 5cac96f937 modpost: remove unneeded initializer in section_rel()
This initializer was added to avoid -Wmaybe-uninitialized (gcc) and
-Wsometimes-uninitialized (clang) warnings.

Now that compilers recognize fatal() never returns, it is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2023-12-10 15:34:37 +09:00
Masahiro Yamada 16a473f60e modpost: inform compilers that fatal() never returns
The function fatal() never returns because modpost_log() calls exit(1)
when LOG_FATAL is passed.

Inform compilers of this fact so that unreachable code flow can be
identified at compile time.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2023-12-10 15:34:37 +09:00
Masahiro Yamada cc87b7c06f modpost: move __attribute__((format(printf, 2, 3))) to modpost.h
This attribute must be added to the function declaration in a header
for comprehensive checking of all the callsites.

Fixes: 6d9a89ea4b ("kbuild: declare the modpost error functions as printf like")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2023-12-10 15:34:37 +09:00
Masahiro Yamada 1c4a7587d1 modpost: fix section mismatch message for RELA
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 93684d3b80 ("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>
2023-11-16 20:14:44 +09:00
Masahiro Yamada 34fcf231dc modpost: squash ALL_{INIT,EXIT}_TEXT_SECTIONS to ALL_TEXT_SECTIONS
ALL_INIT_TEXT_SECTIONS and ALL_EXIT_TEXT_SECTIONS are only used in
the macro definition of ALL_TEXT_SECTIONS.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada b3d4f446fc modpost: merge sectioncheck table entries regarding init/exit sections
Check symbol references from normal sections to init/exit sections in
a single entry.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada e578e4e311 modpost: use ALL_INIT_SECTIONS for the section check from DATA_SECTIONS
ALL_INIT_SECTIONS is defined as follows:

  #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada a3df1526da modpost: disallow the combination of EXPORT_SYMBOL and __meminit*
Theoretically, we could export conditionally-discarded code sections,
such as .meminit*, if all the users can become modular under a certain
condition. However, that would be difficult to control and such a tricky
case has never occurred.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada 48cd8df7af modpost: remove EXIT_SECTIONS macro
ALL_EXIT_SECTIONS and EXIT_SECTIONS are the same. Remove the latter.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada 473a45bb35 modpost: remove MEM_INIT_SECTIONS macro
ALL_XXXINIT_SECTIONS and MEM_INIT_SECTIONS are the same.
Remove the latter.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada e1dc1bfe5b modpost: remove more symbol patterns from the section check whitelist
These symbol patterns were whitelisted to allow them to reference to
functions with the old __devinit and __devexit annotations.

We stopped doing this a long time ago, for example, commit 6f03979051
("Drivers: scsi: remove __dev* attributes.") remove those annotations
from the scsi drivers.

Keep *_ops, *_probe, and *_console, otherwise they will really cause
section mismatch warnings.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada 50cccec15c modpost: disallow *driver to reference .meminit* sections
Drivers must not reference .meminit* sections, which are discarded
when CONFIG_MEMORY_HOTPLUG=n.

The reason for whitelisting "*driver" in the section mismatch check
was to allow drivers to reference symbols annotated as __devinit or
__devexit that existed in the past.

Those annotations were removed by the following commits:

 - 54b956b903 ("Remove __dev* markings from init.h")
 - 92e9e6d1f9 ("modpost.c: Stop checking __dev* section mismatches")

Remove the stale whitelist.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:22 +09:00
Masahiro Yamada 6a4e59eeed linux/init: remove __memexit* annotations
We have never used __memexit, __memexitdata, or __memexitconst.

These were unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2023-10-28 21:31:22 +09:00
Masahiro Yamada 3ada34b0f6 modpost: remove ALL_EXIT_DATA_SECTIONS macro
This is unused.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-28 21:31:21 +09:00
Masahiro Yamada 77f9f57164 modpost: factor out the common boilerplate of section_rel(a)
The first few lines of section_rel() and section_rela() are the same.
They both retrieve the index of the section to which the relocaton
applies, and skip known-good sections. This common code should be moved
to check_sec_ref().

Avoid ugly casts when computing 'start' and 'stop', and also make the
Elf_Rel and Elf_Rela pointers const.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2023-10-18 17:16:09 +09:00
Masahiro Yamada 29ae5c02ed modpost: refactor check_sec_ref()
We can replace &elf->sechdrs[i] with &sechdrs[i] to slightly shorten
the code because we already have the local variable 'sechdrs'.

However, defining 'sechdr' instead shortens the code further.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2023-10-18 17:16:09 +09:00
Masahiro Yamada bd78c9d714 modpost: define TO_NATIVE() using bswap_* functions
The current TO_NATIVE() has some limitations:

 1) You cannot cast the argument.

 2) You cannot pass a variable marked as 'const'.

 3) Passing an array is a bug, but it is not detected.

Impelement TO_NATIVE() using bswap_*() functions. These are GNU
extensions. If we face portability issues, we can port the code from
include/uapi/linux/swab.h.

With this change, get_rel_type_and_sym() can be simplified by casting
the arguments directly.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2023-10-18 17:16:09 +09:00
Jack BrennenandMasahiro Yamada 4074532758 modpost: Optimize symbol search from linear to binary search
Modify modpost to use binary search for converting addresses back
into symbol references.  Previously it used linear search.

This change saves a few seconds of wall time for defconfig builds,
but can save several minutes on allyesconfigs.

Before:
$ make LLVM=1 -j128 allyesconfig vmlinux -s KCFLAGS="-Wno-error"
$ time scripts/mod/modpost -M -m -a -N -o vmlinux.symvers vmlinux.o
198.38user 1.27system 3:19.71elapsed

After:
$ make LLVM=1 -j128 allyesconfig vmlinux -s KCFLAGS="-Wno-error"
$ time scripts/mod/modpost -M -m -a -N -o vmlinux.symvers vmlinux.o
11.91user 0.85system 0:12.78elapsed

Signed-off-by: Jack Brennen <jbrennen@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-03 20:25:59 +09:00
Uwe Kleine-KönigandMasahiro Yamada f177cd0c15 modpost: Don't let "driver"s reference .exit.*
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 0db2524523 ("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>
2023-10-01 14:55:30 +09:00
Linus Torvalds 847165d7c8 Merge tag 'parisc-for-6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
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
2023-09-13 11:35:53 -07:00
Masahiro YamadaandHelge Deller 08700ec705 linux/export: fix reference to exported functions for parisc64
John David Anglin reported parisc has been broken since commit
ddb5cdbafa ("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: ddb5cdbafa ("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>
2023-09-12 17:42:00 +02:00
Denis NikitinandMasahiro Yamada 1ef061a4e2 modpost: Skip .llvm.call-graph-profile section check
.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>
2023-09-01 15:58:17 +09:00
Masahiro Yamada 77f39e9344 modpost: remove ElF_Rela variables from for-loop in section_rel(a)
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>
2023-07-31 23:42:14 +09:00
Masahiro Yamada 4732acb75f modpost: clean up MIPS64 little endian relocation code
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>
2023-07-31 23:42:14 +09:00
Masahiro Yamada 71d965cf35 modpost: pass r_type to addend_*_rel()
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>
2023-07-31 23:42:14 +09:00