Disable SLUB_TINY for build testing

... and don't error out so hard on missing module descriptions.

Before commit 6c6c1fc09de3 ("modpost: require a MODULE_DESCRIPTION()")
we used to warn about miss

Disable SLUB_TINY for build testing

... and don't error out so hard on missing module descriptions.

Before commit 6c6c1fc09de3 ("modpost: require a MODULE_DESCRIPTION()")
we used to warn about missing module descriptions, but only when
building with extra warnigns (ie 'W=1').

After that commit the warning became an unconditional hard error.

And it turns out not all modules have been converted despite the claims
to the contrary. As reported by Damian Tometzki, the slub KUnit test
didn't have a module description, and apparently nobody ever really
noticed.

The reason nobody noticed seems to be that the slub KUnit tests get
disabled by SLUB_TINY, which also ends up disabling a lot of other code,
both in tests and in slub itself. And so anybody doing full build tests
didn't actually see this failre.

So let's disable SLUB_TINY for build-only tests, since it clearly ends
up limiting build coverage. Also turn the missing module descriptions
error back into a warning, but let's keep it around for non-'W=1'
builds.

Reported-by: Damian Tometzki <[email protected]>
Link: https://lore.kernel.org/all/01070196099fd059-e8463438-7b1b-4ec8-816d-173874be9966-000000@eu-central-1.amazonses.com/
Cc: Masahiro Yamada <[email protected]>
Cc: Jeff Johnson <[email protected]>
Fixes: 6c6c1fc09de3 ("modpost: require a MODULE_DESCRIPTION()")
Signed-off-by: Linus Torvalds <[email protected]>

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modpost: require a MODULE_DESCRIPTION()

Since commit 1fffe7a34c89 ("script: modpost: emit a warning when the
description is missing"), a module without a MODULE_DESCRIPTION() has
resulted in a warni

modpost: require a MODULE_DESCRIPTION()

Since commit 1fffe7a34c89 ("script: modpost: emit a warning when the
description is missing"), a module without a MODULE_DESCRIPTION() has
resulted in a warning with make W=1. Since that time, all known
instances of this issue have been fixed. Therefore, now make it an
error if a MODULE_DESCRIPTION() is not present.

Signed-off-by: Jeff Johnson <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: introduce get_basename() helper

The logic to retrieve the basename appears multiple times.
Factor out the common pattern into a helper function.

I copied kbasename() from include/linux/str

modpost: introduce get_basename() helper

The logic to retrieve the basename appears multiple times.
Factor out the common pattern into a helper function.

I copied kbasename() from include/linux/string.h and renamed it
to get_basename().

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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modpost: Fix a few typos in a comment

Namely: s/becasue/because/ and s/wiht/with/ plus an added article.

Signed-off-by: Uwe Kleine-König <[email protected]>
Signed-off-by: Masahiro Yamad

modpost: Fix a few typos in a comment

Namely: s/becasue/because/ and s/wiht/with/ plus an added article.

Signed-off-by: Uwe Kleine-König <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS

Linus observed that the symbol_request(utf8_data_table) call fails when
CONFIG_UNICODE=y and CONFIG_TRIM_UNUSED_KSYMS=y.

sym

kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS

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 dbacb0ef670d ("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 <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: Allow extended modversions without basic MODVERSIONS

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 a

modpost: Allow extended modversions without basic MODVERSIONS

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 <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: Produce extended MODVERSIONS information

Generate both the existing modversions format and the new extended one
when running modpost. Presence of this metadata in the final .ko is
guarded b

modpost: Produce extended MODVERSIONS information

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 <[email protected]>
Signed-off-by: Matthew Maurer <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: zero-pad CRC values in modversion_info array

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 chang

modpost: zero-pad CRC values in modversion_info array

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 <[email protected]>

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modpost: work around unaligned data access error

With the latest binutils, modpost fails with a bus error on some
architectures such as ARM and sparc64.

Since binutils commit 1f1b5e506bf0 ("bfd/ELF

modpost: work around unaligned data access error

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 <[email protected]>
Reported-by: Matthias Klose <[email protected]>
Closes: https://sourceware.org/bugzilla/show_bug.cgi?id=32435
Reported-by: John Paul Adrian Glaubitz <[email protected]>
Closes: https://sourceware.org/bugzilla/show_bug.cgi?id=32493
Signed-off-by: Masahiro Yamada <[email protected]>
Tested-by: John Paul Adrian Glaubitz <[email protected]>

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modpost: distinguish same module paths from different dump files

Since commit 13b25489b6f8 ("kbuild: change working directory to external
module directory with M="), module paths are always relative

modpost: distinguish same module paths from different dump files

Since commit 13b25489b6f8 ("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: 13b25489b6f8 ("kbuild: change working directory to external module directory with M=")
Reported-by: Jon Hunter <[email protected]>
Closes: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Masahiro Yamada <[email protected]>
Tested-by: Jon Hunter <[email protected]>

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modpost: Add .irqentry.text to OTHER_SECTIONS

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
acce

modpost: Add .irqentry.text to OTHER_SECTIONS

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 <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected] # needed for linux-5.4-y
Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: replace tdb_hash() with hash_str()

Use a helper available in scripts/include/hash.h.

Signed-off-by: Masahiro Yamada <[email protected]>

modpost: move strstarts() to modpost.h

This macro is useful in file2alias.c as well.

Signed-off-by: Masahiro Yamada <[email protected]>

modpost: introduce module_alias_printf() helper

The generic ->do_entry() handler is currently limited to returning
a single alias string.

However, this is not flexible enough for several subsystems

modpost: introduce module_alias_printf() helper

The generic ->do_entry() handler is currently limited to returning
a single alias string.

However, this is not flexible enough for several subsystems, which
currently require their own implementations:

- do_usb_table()
- do_of_table()
- do_pnp_device_entry()
- do_pnp_card_entries()

This commit introduces a helper function so that these special cases can
add multiple MODULE_ALIAS() and then migrate to the generic framework.

Signed-off-by: Masahiro Yamada <[email protected]>

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kbuild: compile constant module information only once

Various information about modules is compiled into the info sections.
For that a dedicated .mod.c file is generated by modpost for each module
a

kbuild: compile constant module information only once

Various information about modules is compiled into the info sections.
For that a dedicated .mod.c file is generated by modpost for each module
and then linked into the module.
However most of the information in the .mod.c is the same for all
modules, internal and external.
Split the shared information into a dedicated source file that is
compiled once and then linked into all modules.

This avoids frequent rebuilds for all .mod.c files when using
CONFIG_LOCALVERSION_AUTO because the local version ends up in .mod.c
through UTS_RELEASE and VERMAGIC_STRING.
The modules are still relinked in this case.

The code is also easier to maintain as it's now in a proper source file
instead of an inline string literal.

Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: simplify modpost_log()

With commit cda5f94e88b4 ("modpost: avoid using the alias attribute"),
only two log levels remain: LOG_WARN and LOG_ERROR. Simplify this by
making it a boolean variab

modpost: simplify modpost_log()

With commit cda5f94e88b4 ("modpost: avoid using the alias attribute"),
only two log levels remain: LOG_WARN and LOG_ERROR. Simplify this by
making it a boolean variable.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>

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modpost: improve the section mismatch warning format

This commit improves the section mismatch warning format when there is
no suitable symbol name to print.

The section mismatch warning prints the

modpost: improve the section mismatch warning format

This commit improves the section mismatch warning format when there is
no suitable symbol name to print.

The section mismatch warning prints the reference source in the form
of <symbol_name>+<offset> and the reference destination in the form
of <symbol_name>.

However, there are some corner cases where <symbol_name> becomes
"(unknown)", as reported in commit 23dfd914d2bf ("modpost: fix null
pointer dereference").

In such cases, it is better to print the symbol address.

Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: replace the use of NOFAIL() with xmalloc() etc.

I think x*alloc() functions are cleaner.

Signed-off-by: Masahiro Yamada <[email protected]>

modpost: detect endianness on run-time

Endianness is currently detected on compile-time, but we can defer this
until run-time. This change avoids re-executing scripts/mod/mk_elfconfig
even if modpos

modpost: detect endianness on run-time

Endianness is currently detected on compile-time, but we can defer this
until run-time. This change avoids re-executing scripts/mod/mk_elfconfig
even if modpost in the linux-headers package needs to be rebuilt for a
foreign architecture.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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modpost: use generic macros for hash table implementation

Use macros provided by hashtable.h

Signed-off-by: Masahiro Yamada <[email protected]>

kbuild: move some helper headers from scripts/kconfig/ to scripts/include/

Move array_size.h, hashtable.h, list.h, list_types.h from scripts/kconfig/
to scripts/include/.

These headers will be usef

kbuild: move some helper headers from scripts/kconfig/ to scripts/include/

Move array_size.h, hashtable.h, list.h, list_types.h from scripts/kconfig/
to scripts/include/.

These headers will be useful for other host programs.

Remove scripts/mod/list.h.

Signed-off-by: Masahiro Yamada <[email protected]>

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modpost: rename R_ARM_THM_CALL to R_ARM_THM_PC22

/usr/include/elf.h, which originates from the glibc/musl, defines
R_ARM_THM_PC22 instead of R_ARM_THM_CALL.

Signed-off-by: Masahiro Yamada <masahiro

modpost: rename R_ARM_THM_CALL to R_ARM_THM_PC22

/usr/include/elf.h, which originates from the glibc/musl, defines
R_ARM_THM_PC22 instead of R_ARM_THM_CALL.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>

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modpost: remove self-definitions of R_ARM_* macros

Commit f5983dab0ead ("modpost: define more R_ARM_* for old
distributions") added self-definitions for the R_ARM_* macros to fix
build errors on Cen

modpost: remove self-definitions of R_ARM_* macros

Commit f5983dab0ead ("modpost: define more R_ARM_* for old
distributions") added self-definitions for the R_ARM_* macros to fix
build errors on CentOS 7.

RHEL/CentOS 7 were retired at the end of June.

Remove all the R_ARM_* definitions (except for R_ARM_THM_CALL), which
should be available in recent distributions.

glibc and musl added most of R_ARM_* macros in 2013. [1] [2]

[1]: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=08cbd996d33114ca50644d060fbe3a08260430fb
[2]: https://git.musl-libc.org/cgit/musl/commit/?id=268375c1c017c0bdefeed1a330811e433c4dfaef

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>

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modpost: Enable section warning from *driver to .exit.text

There used to be several offenders, but now that for all of them patches
were sent and most of them were applied, enable the warning also f

modpost: Enable section warning from *driver to .exit.text

There used to be several offenders, but now that for all of them patches
were sent and most of them were applied, enable the warning also for
builds without W=1.

Signed-off-by: Uwe Kleine-König <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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init/modpost: conditionally check section mismatch to __meminit*

This reverts commit eb8f689046b8 ("Use separate sections for __dev/
_cpu/__mem code/data").

Check section mismatch to __meminit* onl

init/modpost: conditionally check section mismatch to __meminit*

This reverts commit eb8f689046b8 ("Use separate sections for __dev/
_cpu/__mem code/data").

Check section mismatch to __meminit* only when CONFIG_MEMORY_HOTPLUG=n.

With this change, the linker script and modpost become simpler, and we
can get rid of the __ref annotations from the memory hotplug code.

[[email protected]: remove MEM_KEEP from arch/powerpc/kernel/vmlinux.lds.S]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
Reviewed-by: Wei Yang <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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