The current format of *.mod is like this:
line 1: directory path to the .ko file
line 2: a list of objects linked into this module
line 3: unresolved symbols (only when CONFIG_TRIM_UNUSED_KSYMS=y)
Now that *.mod and *.ko are created in the same directory, the line 1
provides no valuable information. It can be derived by replacing the
extension .mod with .ko. In fact, nobody uses the first line any more.
Cut down the first line.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
While descending directories, Kbuild produces objects for modules,
but do not link final *.ko files; it is done in the modpost.
To keep track of modules, Kbuild creates a *.mod file in $(MODVERDIR)
for every module it is building. Some post-processing steps read the
necessary information from *.mod files. This avoids descending into
directories again. This mechanism was introduced in 2003 or so.
Later, commit 551559e13a ("kbuild: implement modules.order") added
modules.order. So, we can simply read it out to know all the modules
with directory paths. This is easier than parsing the first line of
*.mod files.
$(MODVERDIR) has a flat directory structure, that is, *.mod files
are named only with base names. This is based on the assumption that
the module name is unique across the tree. This assumption is really
fragile.
Stephen Rothwell reported a race condition caused by a module name
conflict:
https://lkml.org/lkml/2019/5/13/991
In parallel building, two different threads could write to the same
$(MODVERDIR)/*.mod simultaneously.
Non-unique module names are the source of all kind of troubles, hence
commit 3a48a91901 ("kbuild: check uniqueness of module names")
introduced a new checker script.
However, it is still fragile in the build system point of view because
this race happens before scripts/modules-check.sh is invoked. If it
happens again, the modpost will emit unclear error messages.
To fix this issue completely, create *.mod with full directory path
so that two threads never attempt to write to the same file.
$(MODVERDIR) is no longer needed.
Since modules with directory paths are listed in modules.order, Kbuild
is still able to find *.mod files without additional descending.
I also killed cmd_secanalysis; scripts/mod/sumversion.c computes MD4 hash
for modules with MODULE_VERSION(). When CONFIG_DEBUG_SECTION_MISMATCH=y,
it occurs not only in the modpost stage, but also during directory
descending, where sumversion.c may parse stale *.mod files. It would emit
'No such file or directory' warning when an object consisting a module is
renamed, or when a single-obj module is turned into a multi-obj module or
vice versa.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Fix commit 56067812d5 ("kbuild: modversions: add infrastructure for
emitting relative CRCs") where CRCs are interpreted in host byte order
rather than proper kernel byte order. The bug is conditional on
CONFIG_MODULE_REL_CRCS.
For example, when loading a BE module into a BE kernel compiled with a LE
system, the error "disagrees about version of symbol module_layout" is
produced. A message such as "Found checksum D7FA6856 vs module 5668FAD7"
will be given with debug enabled, which indicates an obvious endian
problem within __kcrctab within the kernel image.
The general solution is to use the macro TO_NATIVE, as is done in
similar cases throughout modpost.c. With this correction it has been
verified that a BE kernel compiled with a LE system accepts BE modules.
This change has also been verified with a LE kernel compiled with a LE
system, in which case TO_NATIVE returns its value unmodified since the
byte orders match. This is by far the common case.
Fixes: 56067812d5 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Signed-off-by: Fredrik Noring <noring@nocrew.org>
Cc: stable@vger.kernel.org
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Unless CONFIG_DEBUG_SECTION_MISMATCH is enabled, modpost only shows
the number of section mismatches.
If you want to know the symbols causing the issue, you need to rebuild
with CONFIG_DEBUG_SECTION_MISMATCH. It is tedious.
I think it is fine to show annoying warning when a new section mismatch
comes in.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull x86 platform driver updates from Darren Hart:
- use MODULE_DEVICE_TABLE across several wmi drivers, keeping
wmi_device_id and MODULE_ALIAS() declarations in sync
- add several Ideapad models to the no_hw_rfkill list
- add support for new Mellanox platforms, including new fan and LED
functionality
- address Dell keyboard backlight change event and power button release
issues
- update dell_rbu to use appropriate memory allocation mechanisms
- several small fixes and Ice Lake support for intel_pmc_core
- fix a suspend regression for Cherry Trail based devices in
intel_int0002_vgpio
- a few other routine fixes
* tag 'platform-drivers-x86-v5.1-1' of git://git.infradead.org/linux-platform-drivers-x86: (50 commits)
MAINTAINERS: Include mlxreg.h in Mellanox Platform Driver files
platform/x86: ideapad-laptop: Add S130-14IGM to no_hw_rfkill list
platform/x86: mlx-platform: Fix access mode for fan_dir attribute
platform/x86: mlx-platform: Add UID LED for the next generation systems
platform/x86: mlx-platform: Add extra CPLD for next generation systems
platform/x86: wmi-bmof: use MODULE_DEVICE_TABLE() instead of MODULE_ALIAS()
platform/x86: intel-wmi-thunderbolt: use MODULE_DEVICE_TABLE() instead of MODULE_ALIAS()
platform/x86: huawei-wmi: use MODULE_DEVICE_TABLE() instead of MODULE_ALIAS()
platform/x86: dell-wmi: use MODULE_DEVICE_TABLE() instead of MODULE_ALIAS()
platform/x86: dell-wmi-descriptor: use MODULE_DEVICE_TABLE() instead of MODULE_ALIAS()
platform/x86: dell-smbios-wmi: use MODULE_DEVICE_TABLE() instead of MODULE_ALIAS()
platform/x86: wmi: add WMI support to MODULE_DEVICE_TABLE()
platform/x86: wmi: move struct wmi_device_id to mod_devicetable.h
modpost: file2alias: define size of alias
platform/x86: touchscreen_dmi: Add info for the CHUWI Hi10 Air tablet
platform/x86: ideapad-laptop: Add Ideapad 530S-14ARR to no_hw_rfkill list
platform/x86: ideapad-laptop: Add Yoga C930 to no_hw_rfkill_list
platform/x86: intel_pmc_core: Quirk to ignore XTAL shutdown
platform/x86: intel_pmc_core: Add Package cstates residency info
platform/x86: intel_pmc_core: Add ICL platform support
...
The kernel provides the macro MODULE_DEVICE_TABLE() where driver authors
can specify their device type and their array of device_ids and thereby
trigger the generation of the appropriate MODULE_ALIAS() output. This is
opposed to having to specify one MODULE_ALIAS() for each device. The WMI
device type is currently not supported.
While using MODULE_DEVICE_TABLE() does increase the complexity as well
as spreading out the implementation across the kernel, it does come with
some benefits too;
* It makes different drivers look more similar; if you can specify the
array of device_ids any device type specific input to MODULE_ALIAS()
will automatically be generated for you.
* It helps each driver avoid keeping multiple versions of the same
information in sync. That is, both the array of device_ids and the
potential multitude of MODULE_ALIAS()'s.
Add WMI support to MODULE_DEVICE_TABLE() by adding info about struct
wmi_device_id in devicetable-offsets.c and add a WMI entry point in
file2alias.c.
The type argument for MODULE_DEVICE_TABLE(type, name) is wmi.
Suggested-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
In preparation for adding WMI support to MODULE_DEVICE_TABLE() move the
definition of struct wmi_device_id to mod_devicetable.h and inline
guid_string in the struct.
Changing guid_string to an inline char array changes the loop conditions
when looping over an array of struct wmi_device_id. Therefore update
wmi_dev_match()'s loop to check for an empty guid_string instead of a
NULL pointer.
Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
[dvhart: Move UUID_STRING_LEN define to this patch]
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
The size of the variable alias provided to do_entry functions are
currently not readily available. Thus hindering do_entry functions to
perform bounds checking.
Define the macro ALIAS_SIZE containing the size of the variable alias.
Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Introduce a generic TEE bus driver concept for TEE based kernel drivers
which would like to communicate with TEE based devices/services. Also
add support in module device table for these new TEE based devices.
In this TEE bus concept, devices/services are identified via Universally
Unique Identifier (UUID) and drivers register a table of device UUIDs
which they can support.
So this TEE bus framework registers following apis:
- match(): Iterates over the driver UUID table to find a corresponding
match for device UUID. If a match is found, then this particular device
is probed via corresponding probe api registered by the driver. This
process happens whenever a device or a driver is registered with TEE
bus.
- uevent(): Notifies user-space (udev) whenever a new device is registered
on this bus for auto-loading of modularized drivers.
Also this framework allows for device enumeration to be specific to
corresponding TEE implementation like OP-TEE etc.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
I am eagar to build under the scripts/ directory only with $(HOSTCC),
but scripts/mod/ highly depends on the $(CC) and target arch headers.
That it why the 'scripts' target must depend on 'asm-generic',
'gcc-plugins', and $(autoksyms_h).
Move it to the 'prepare0' stage. I know this is a cheesy workaround,
but better than the current situation.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Probably, this is just a matter of the order of error/warning
messages. Merge the two for-loops.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
You do not need to iterate over all modules for resetting ->seen flag
because add_depends() is only interested in modules that export symbols
referenced from the given 'mod'.
This also avoids shadowing the 'modules' parameter of add_depends().
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Use specific prototype instead of an opaque pointer so that the
compiler can catch function prototype mismatch.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Mathieu Malaterre <malat@debian.org>
Commit e49ce14150 ("modpost: use linker section to generate table.")
was not so cool as we had expected first; it ended up with ugly section
hacks when commit dd2a3acaec ("mod/file2alias: make modpost compile
on darwin again") came in.
Given a certain degree of unknowledge about the link stage of host
programs, I really want to see simple, stupid table lookup so that
this works in the same way regardless of the underlying executable
format.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Mathieu Malaterre <malat@debian.org>
During development of a serial console driver with a gcc 8.2.0
toolchain for RISC-V, the following modpost warning appeared:
----
WARNING: vmlinux.o(.data+0x19b10): Section mismatch in reference from the variable .LANCHOR1 to the function .init.text:sifive_serial_console_setup()
The variable .LANCHOR1 references
the function __init sifive_serial_console_setup()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console
----
".LANCHOR1" is an ELF local symbol, automatically created by gcc's section
anchor generation code:
https://gcc.gnu.org/onlinedocs/gccint/Anchored-Addresses.htmlhttps://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/varasm.c;h=cd9591a45617464946dcf9a126dde277d9de9804;hb=9fb89fa845c1b2e0a18d85ada0b077c84508ab78#l7473
This was verified by compiling the kernel with -fno-section-anchors
and observing that the ".LANCHOR1" ELF local symbol disappeared, and
modpost no longer warned about the section mismatch. The serial
driver code idiom triggering the warning is standard Linux serial
driver practice that has a specific whitelist inclusion in modpost.c.
I'm neither a modpost nor an ELF expert, but naively, it doesn't seem
useful for modpost to report section mismatch warnings caused by ELF
local symbols by default. Local symbols have compiler-generated
names, and thus bypass modpost's whitelisting algorithm, which relies
on the presence of a non-autogenerated symbol name. This increases
the likelihood that false positive warnings will be generated (as in
the above case).
Thus, disable section mismatch reporting on ELF local symbols. The
rationale here is similar to that of commit 2e3a10a155 ("ARM: avoid
ARM binutils leaking ELF local symbols") and of similar code already
present in modpost.c:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/mod/modpost.c?h=v4.19-rc4&id=7876320f88802b22d4e2daf7eb027dd14175a0f8#n1256
This third version of the patch implements a suggestion from Masahiro
Yamada <yamada.masahiro@socionext.com> to restructure the code as an
additional pattern matching step inside secref_whitelist(), and
further improves the patch description.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Drop modpost command line switches that are no longer used by
makefile.modpost, upon request from Sam Ravnborg <sam@ravnborg.org>,
who wrote:
modpost is not supposed to be used outside the kernel build. [...]
I checked if there were any options supported by modpost that
was not configurable in Makefile.modpost.
And I could see that the -M and -K options in getopt() were leftovers.
The code that used these option was dropped in:
commit a8773769d1 ("Kbuild: clear marker out of modpost")
Could you add a patch that delete these on top of what you already have.
https://lore.kernel.org/lkml/20181020140835.GA3351@ravnborg.org/
Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
If an ARM mapping symbol shares an address with a valid symbol,
find_elf_symbol can currently return the mapping symbol instead, as the
symbol is not validated. This can result in confusing warnings:
WARNING: vmlinux.o(.text+0x18f4028): Section mismatch in reference
from the function set_reset_devices() to the variable .init.text:$x.0
This change adds a call to is_valid_name to find_elf_symbol, similarly
to how it's already used in find_elf_symbol2.
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Pull Kbuild updates from Masahiro Yamada:
- optimize kallsyms slightly
- remove check for old CFLAGS usage
- add some compiler flags unconditionally instead of evaluating
$(call cc-option,...)
- fix variable shadowing in host tools
- refactor scripts/mkmakefile
- refactor various makefiles
* tag 'kbuild-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
modpost: Create macro to avoid variable shadowing
ASN.1: Remove unnecessary shadowed local variable
kbuild: use 'else ifeq' for checksrc to improve readability
kbuild: remove unneeded link_multi_deps
kbuild: add -Wno-unused-but-set-variable flag unconditionally
kbuild: add -Wdeclaration-after-statement flag unconditionally
kbuild: add -Wno-pointer-sign flag unconditionally
modpost: remove leftover symbol prefix handling for module device table
kbuild: simplify command line creation in scripts/mkmakefile
kbuild: do not pass $(objtree) to scripts/mkmakefile
kbuild: remove user ID check in scripts/mkmakefile
kbuild: remove VERSION and PATCHLEVEL from $(objtree)/Makefile
kbuild: add --include-dir flag only for out-of-tree build
kbuild: remove dead code in cmd_files calculation in top Makefile
kbuild: hide most of targets when running config or mixed targets
kbuild: remove old check for CFLAGS use
kbuild: prefix Makefile.dtbinst path with $(srctree) unconditionally
kallsyms: remove left-over Blackfin code
kallsyms: reduce size a little on 64-bit
Create DEF_FIELD_ADDR_VAR as a more generic version of the DEF_FIELD_ADD
macro, allowing usage of a variable name other than the struct element name.
Also, sets DEF_FIELD_ADDR as a specific usage of DEF_FILD_ADDR_VAR in which
the var name is the same as the struct element name.
Then, makes use of DEF_FIELD_ADDR_VAR to create a variable of another name,
in order to avoid variable shadowing.
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Blackfin and metag were the only architectures that prefix symbols with
an underscore. They were removed by commit 4ba66a9760 ("arch: remove
blackfin port"), commit bb6fb6dfcc ("metag: Remove arch/metag/"),
respectively.
It is no longer necessary to handle <prefix> part of module device
table symbols.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Using macros in inline assembly allows us to work around bugs
in GCC's inlining decisions.
Compile macros.S and use it to assemble all C files.
Currently only x86 will use it.
Background:
The inlining pass of GCC doesn't include an assembler, so it's not aware
of basic properties of the generated code, such as its size in bytes,
or that there are such things as discontiuous blocks of code and data
due to the newfangled linker feature called 'sections' ...
Instead GCC uses a lazy and fragile heuristic: it does a linear count of
certain syntactic and whitespace elements in inlined assembly block source
code, such as a count of new-lines and semicolons (!), as a poor substitute
for "code size and complexity".
Unsurprisingly this heuristic falls over and breaks its neck whith certain
common types of kernel code that use inline assembly, such as the frequent
practice of putting useful information into alternative sections.
As a result of this fresh, 20+ years old GCC bug, GCC's inlining decisions
are effectively disabled for inlined functions that make use of such asm()
blocks, because GCC thinks those sections of code are "large" - when in
reality they are often result in just a very low number of machine
instructions.
This absolute lack of inlining provess when GCC comes across such asm()
blocks both increases generated kernel code size and causes performance
overhead, which is particularly noticeable on paravirt kernels, which make
frequent use of these inlining facilities in attempt to stay out of the
way when running on baremetal hardware.
Instead of fixing the compiler we use a workaround: we set an assembly macro
and call it from the inlined assembly block. As a result GCC considers the
inline assembly block as a single instruction. (Which it often isn't but I digress.)
This uglifies and bloats the source code - for example just the refcount
related changes have this impact:
Makefile | 9 +++++++--
arch/x86/Makefile | 7 +++++++
arch/x86/kernel/macros.S | 7 +++++++
scripts/Kbuild.include | 4 +++-
scripts/mod/Makefile | 2 ++
5 files changed, 26 insertions(+), 3 deletions(-)
Yay readability and maintainability, it's not like assembly code is hard to read
and maintain ...
We also hope that GCC will eventually get fixed, but we are not holding
our breath for that. Yet we are optimistic, it might still happen, any decade now.
[ mingo: Wrote new changelog describing the background. ]
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kbuild@vger.kernel.org
Link: http://lkml.kernel.org/r/20181003213100.189959-3-namit@vmware.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull USB/PHY updates from Greg KH:
"Here is the big USB and phy driver patch set for 4.19-rc1.
Nothing huge but there was a lot of work that happened this
development cycle:
- lots of type-c work, with drivers graduating out of staging, and
displayport support being added.
- new PHY drivers
- the normal collection of gadget driver updates and fixes
- code churn to work on the urb handling path, using irqsave()
everywhere in anticipation of making this codepath a lot simpler in
the future.
- usbserial driver fixes and reworks
- other misc changes
All of these have been in linux-next with no reported issues for a
while"
* tag 'usb-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (159 commits)
USB: serial: pl2303: add a new device id for ATEN
usb: renesas_usbhs: Kconfig: convert to SPDX identifiers
usb: dwc3: gadget: Check MaxPacketSize from descriptor
usb: dwc2: Turn on uframe_sched on "stm32f4x9_fsotg" platforms
usb: dwc2: Turn on uframe_sched on "amlogic" platforms
usb: dwc2: Turn on uframe_sched on "his" platforms
usb: dwc2: Turn on uframe_sched on "bcm" platforms
usb: dwc2: gadget: ISOC's starting flow improvement
usb: dwc2: Make dwc2_readl/writel functions endianness-agnostic.
usb: dwc3: core: Enable AutoRetry feature in the controller
usb: dwc3: Set default mode for dwc_usb31
usb: gadget: udc: renesas_usb3: Add register of usb role switch
usb: dwc2: replace ioread32/iowrite32_rep with dwc2_readl/writel_rep
usb: dwc2: Modify dwc2_readl/writel functions prototype
usb: dwc3: pci: Intel Merrifield can be host
usb: dwc3: pci: Supply device properties via driver data
arm64: dts: dwc3: description of incr burst type
usb: dwc3: Enable undefined length INCR burst type
usb: dwc3: add global soc bus configuration reg0
usb: dwc3: Describe 'wakeup_work' field of struct dwc3_pci
...
