Linus observed that the symbol_request(utf8_data_table) call fails when
CONFIG_UNICODE=y and CONFIG_TRIM_UNUSED_KSYMS=y.
symbol_get() relies on the symbol data being present in the ksymtab for
symbol lookups. However, EXPORT_SYMBOL_GPL(utf8_data_table) is dropped
due to CONFIG_TRIM_UNUSED_KSYMS, as no module references it in this case.
Probably, this has been broken since commit dbacb0ef67 ("kconfig option
for TRIM_UNUSED_KSYMS").
This commit addresses the issue by leveraging modpost. Symbol names
passed to symbol_get() are recorded in the special .no_trim_symbol
section, which is then parsed by modpost to forcibly keep such symbols.
The .no_trim_symbol section is discarded by the linker scripts, so there
is no impact on the size of the final vmlinux or modules.
This commit cannot resolve the issue for direct calls to __symbol_get()
because the symbol name is not known at compile-time.
Although symbol_get() may eventually be deprecated, this workaround
should be good enough meanwhile.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Pull Kbuild updates from Masahiro Yamada:
- Support multiple hook locations for maint scripts of Debian package
- Remove 'cpio' from the build tool requirement
- Introduce gendwarfksyms tool, which computes CRCs for export symbols
based on the DWARF information
- Support CONFIG_MODVERSIONS for Rust
- Resolve all conflicts in the genksyms parser
- Fix several syntax errors in genksyms
* tag 'kbuild-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (64 commits)
kbuild: fix Clang LTO with CONFIG_OBJTOOL=n
kbuild: Strip runtime const RELA sections correctly
kconfig: fix memory leak in sym_warn_unmet_dep()
kconfig: fix file name in warnings when loading KCONFIG_DEFCONFIG_LIST
genksyms: fix syntax error for attribute before init-declarator
genksyms: fix syntax error for builtin (u)int*x*_t types
genksyms: fix syntax error for attribute after 'union'
genksyms: fix syntax error for attribute after 'struct'
genksyms: fix syntax error for attribute after abstact_declarator
genksyms: fix syntax error for attribute before nested_declarator
genksyms: fix syntax error for attribute before abstract_declarator
genksyms: decouple ATTRIBUTE_PHRASE from type-qualifier
genksyms: record attributes consistently for init-declarator
genksyms: restrict direct-declarator to take one parameter-type-list
genksyms: restrict direct-abstract-declarator to take one parameter-type-list
genksyms: remove Makefile hack
genksyms: fix last 3 shift/reduce conflicts
genksyms: fix 6 shift/reduce conflicts and 5 reduce/reduce conflicts
genksyms: reduce type_qualifier directly to decl_specifier
genksyms: rename cvar_qualifier to type_qualifier
...
If you know that your kernel modules will only ever be loaded by a newer
kernel, you can disable BASIC_MODVERSIONS to save space. This also
allows easy creation of test modules to see how tooling will respond to
modules that only have the new format.
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Generate both the existing modversions format and the new extended one
when running modpost. Presence of this metadata in the final .ko is
guarded by CONFIG_EXTENDED_MODVERSIONS.
We no longer generate an error on long symbols in modpost if
CONFIG_EXTENDED_MODVERSIONS is set, as they can now be appropriately
encoded in the extended section. These symbols will be skipped in the
previous encoding. An error will still be generated if
CONFIG_EXTENDED_MODVERSIONS is not set.
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
I do not think the '#' flag is useful here because adding the explicit
'0x' is clearer. Add the '0' flag to zero-pad the CRC values.
This change gives better alignment in the generated *.mod.c files.
There is no impact to the compiled modules.
[Before]
$ grep -A5 modversion_info fs/efivarfs/efivarfs.mod.c
static const struct modversion_info ____versions[]
__used __section("__versions") = {
{ 0x907d14d, "blocking_notifier_chain_register" },
{ 0x53d3b64, "simple_inode_init_ts" },
{ 0x65487097, "__x86_indirect_thunk_rax" },
{ 0x122c3a7e, "_printk" },
[After]
$ grep -A5 modversion_info fs/efivarfs/efivarfs.mod.c
static const struct modversion_info ____versions[]
__used __section("__versions") = {
{ 0x0907d14d, "blocking_notifier_chain_register" },
{ 0x053d3b64, "simple_inode_init_ts" },
{ 0x65487097, "__x86_indirect_thunk_rax" },
{ 0x122c3a7e, "_printk" },
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
With the latest binutils, modpost fails with a bus error on some
architectures such as ARM and sparc64.
Since binutils commit 1f1b5e506bf0 ("bfd/ELF: restrict file alignment
for object files"), the byte offset to each section (sh_offset) in
relocatable ELF is no longer guaranteed to be aligned.
modpost parses MODULE_DEVICE_TABLE() data structures, which are usually
located in the .rodata section. If it is not properly aligned, unaligned
access errors may occur.
To address the issue, this commit imports the get_unaligned() helper
from include/linux/unaligned.h.
The get_unaligned_native() helper caters to the endianness in addition
to handling the unaligned access.
I slightly refactored do_pcmcia_entry() and do_input() to avoid writing
back to an unaligned address. (We would need the put_unaligned() helper
to do that.)
The addend_*_rel() functions need similar adjustments because the .text
sections are not aligned either.
It seems that the .symtab, .rel.* and .rela.* sections are still aligned.
Keep normal pointer access for these sections to avoid unnecessary
performance costs.
Reported-by: Paulo Pisati <paolo.pisati@canonical.com>
Reported-by: Matthias Klose <doko@debian.org>
Closes: https://sourceware.org/bugzilla/show_bug.cgi?id=32435
Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Closes: https://sourceware.org/bugzilla/show_bug.cgi?id=32493
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Optimize the size of guid_name[], as it only requires 1 additional byte
for '\0' instead of 2.
Simplify the loop by incrementing the iterator by 1 instead of 2.
Remove the unnecessary TO_NATIVE() call, as the guid is represented as
a byte stream.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
This loop should iterate over the range from 'min' to 'max' inclusively.
The last interation is missed.
Fixes: 1d8f430c15 ("[PATCH] Input: add modalias support")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Since commit 13b25489b6 ("kbuild: change working directory to external
module directory with M="), module paths are always relative to the top
of the external module tree.
The module paths recorded in Module.symvers are no longer globally unique
when they are passed via KBUILD_EXTRA_SYMBOLS for building other external
modules, which may result in false-positive "exported twice" errors.
Such errors should not occur because external modules should be able to
override in-tree modules.
To address this, record the dump file path in struct module and check it
when searching for a module.
Fixes: 13b25489b6 ("kbuild: change working directory to external module directory with M=")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Closes: https://lore.kernel.org/all/eb21a546-a19c-40df-b821-bbba80f19a3d@nvidia.com/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
The compiler can fully inline the actual handler function of an interrupt
entry into the .irqentry.text entry point. If such a function contains an
access which has an exception table entry, modpost complains about a
section mismatch:
WARNING: vmlinux.o(__ex_table+0x447c): Section mismatch in reference ...
The relocation at __ex_table+0x447c references section ".irqentry.text"
which is not in the list of authorized sections.
Add .irqentry.text to OTHER_SECTIONS to cure the issue.
Reported-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # needed for linux-5.4-y
Link: https://lore.kernel.org/all/20241128111844.GE10431@google.com/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The first error message in device_id_check() is obscure and can be
misleading because the cause of the error is unlikely to be found in
the struct definition in mod_devicetable.h.
This type of error occurs when an array is passed to an incorrect type
of MODULE_DEVICE_TABLE().
[Example 1]
static const struct acpi_device_id foo_ids[] = {
{ "FOO" },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, foo_ids);
Currently, modpost outputs a meaningless suggestion:
ERROR: modpost: ...: sizeof(struct of_device_id)=200 is not a modulo of the size of section __mod_device_table__of__<identifier>=64.
Fix definition of struct of_device_id in mod_devicetable.h
The root cause here is that MODULE_DEVICE_TABLE(of, ...) is used instead
of the correct MODULE_DEVICE_TABLE(acpi, ...).
This commit provides a more intuitive error message:
ERROR: modpost: ...: type mismatch between foo_ids[] and MODULE_DEVICE_TABLE(of, ...)
The second error message, related to a missing terminator, is too
verbose.
[Example 2]
static const struct acpi_device_id foo_ids[] = {
{ "FOO" },
};
MODULE_DEVICE_TABLE(acpi, foo_ids);
The current error message is overly long, and does not pinpoint the
incorrect array:
...: struct acpi_device_id is 32 bytes. The last of 1 is:
0x46 0x4f 0x4f 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
ERROR: modpost: ...: struct acpi_device_id is not terminated with a NULL entry!
This commit changes it to a more concise error message, sufficient to
identify the incorrect array:
ERROR: modpost: ...: foo_ids[] is not terminated with a NULL entry
Lastly, this commit squashes device_id_check() into do_table() and
changes fatal() into error(), allowing modpost to continue processing
other modules.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit renames the alias symbol, __mod_<type>__<name>_device_table
to __mod_device_table__<type>__<name>.
This change simplifies the code slightly, as there is no longer a need
to check both the prefix and suffix.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit renames the variables in handle_moddevtable() as follows:
name -> type
namelen -> typelen
identifier -> name
These changes align with the definition in include/linux/module.h:
extern typeof(name) __mod_##type##__##name##_device_table
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
do_usb_table() no longer needs to iterate over the usb_device_id array.
Convert it to a generic ->do_entry() handler.
This is the last special case. Clean up handle_moddevtable().
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
do_of_table() no longer needs to iterate over the of_device_id array.
Convert it to a generic ->do_entry() handler.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
do_pnp_device_entry() no longer needs to iterate over the
pnp_device_id array.
Convert it to a generic ->do_entry() handler.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
do_pnp_card_entries() no longer needs to iterate over the
pnp_card_device_id array.
Convert it to a generic ->do_entry() handler.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The do_*_entry() functions cannot check the length of the given buffer.
Use module_alias_printf() helper consistently for these functions.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Replace the first argument with a pointer to struct module.
'filename' can be replaced with mod->name.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
