18 Oct, 2019
3 commits
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The introduction of Symbol Namespaces changed the naming schema of the
__ksymtab entries from __kysmtab__symbol to __ksymtab_NAMESPACE.symbol.That caused some breakages in tools that depend on the name layout in
either the binaries(vmlinux,*.ko) or in System.map. E.g. kmod's depmod
would not be able to read System.map without a patch to support symbol
namespaces. A warning reported by depmod for namespaced symbols would
look likedepmod: WARNING: [...]/uas.ko needs unknown symbol usb_stor_adjust_quirks
In order to address this issue, revert to the original naming scheme and
rather read the __kstrtabns_ entries and their corresponding
values from __ksymtab_strings to update the namespace values for
symbols. After having read all symbols and handled them in
handle_modversions(), the symbols are created. In a second pass, read
the __kstrtabns_ entries and update the namespaces accordingly.Fixes: 8651ec01daed ("module: add support for symbol namespaces.")
Reported-by: Stefan Wahren
Suggested-by: Masahiro Yamada
Acked-by: Will Deacon
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Masahiro Yamada
Signed-off-by: Matthias Maennich
Signed-off-by: Jessica Yu -
Setting the symbol namespace of a symbol within sym_add_exported feels
displaced and lead to issues in the current implementation of symbol
namespaces. This patch makes updating the namespace an explicit call to
decouple it from adding a symbol to the export list.Acked-by: Will Deacon
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Masahiro Yamada
Signed-off-by: Matthias Maennich
Signed-off-by: Jessica Yu -
Let the function 'sym_update_namespace' take care of updating the
namespace for a symbol. While this currently only replaces one single
location where namespaces are updated, in a following patch, this
function will get more call sites.The function signature is intentionally close to sym_update_crc and
taking the name by char* seems like unnecessary work as the symbol has
to be looked up again. In a later patch of this series, this concern
will be addressed.This function ensures that symbol::namespace is either NULL or has a
valid non-empty value. Previously, the empty string was considered 'no
namespace' as well and this lead to confusion.Acked-by: Will Deacon
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Masahiro Yamada
Signed-off-by: Matthias Maennich
Signed-off-by: Jessica Yu
12 Oct, 2019
1 commit
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Pull module fixes from Jessica Yu:
"Code cleanups and kbuild/namespace related fixups from Masahiro.Most importantly, it fixes a namespace-related modpost issue for
external module builds- Fix broken external module builds due to a modpost bug in
read_dump(), where the namespace was not being strdup'd and
sym->namespace would be set to bogus data.- Various namespace-related kbuild fixes and cleanups thanks to
Masahiro Yamada"* tag 'modules-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
doc: move namespaces.rst from kbuild/ to core-api/
nsdeps: make generated patches independent of locale
nsdeps: fix hashbang of scripts/nsdeps
kbuild: fix build error of 'make nsdeps' in clean tree
module: rename __kstrtab_ns_* to __kstrtabns_* to avoid symbol conflict
modpost: fix broken sym->namespace for external module builds
module: swap the order of symbol.namespace
scripts: add_namespace: Fix coccicheck failed
08 Oct, 2019
2 commits
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Currently, external module builds produce tons of false-positives:
WARNING: module uses symbol from namespace , but does not import it.
Here, the part shows a random string.
When you build external modules, the symbol info of vmlinux and
in-kernel modules are read from $(objtree)/Module.symvers, but
read_dump() is buggy in multiple ways:[1] When the modpost is run for vmlinux and in-kernel modules,
sym_extract_namespace() allocates memory for the namespace. On the
other hand, read_dump() does not, then sym->namespace will point to
somewhere in the line buffer of get_next_line(). The data in the
buffer will be replaced soon, and sym->namespace will end up with
pointing to unrelated data. As a result, check_exports() will show
random strings in the warning messages.[2] When there is no namespace, sym_extract_namespace() returns NULL.
On the other hand, read_dump() sets namespace to an empty string "".
(but, it will be later replaced with unrelated data due to bug [1].)
The check_exports() shows a warning unless exp->namespace is NULL,
so every symbol read from read_dump() emits the warning, which is
mostly false positive.To address [1], sym_add_exported() calls strdup() for s->namespace.
The namespace from sym_extract_namespace() must be freed to avoid
memory leak.For [2], I changed the if-conditional in check_exports().
This commit also fixes sym_add_exported() to set s->namespace correctly
when the symbol is preloaded.Reviewed-by: Matthias Maennich
Signed-off-by: Masahiro Yamada
Signed-off-by: Jessica Yu -
Currently, EXPORT_SYMBOL_NS(_GPL) constructs the kernel symbol as
follows:__ksymtab_SYMBOL.NAMESPACE
The sym_extract_namespace() in modpost allocates memory for the part
SYMBOL.NAMESPACE when '.' is contained. One problem is that the pointer
returned by strdup() is lost because the symbol name will be copied to
malloc'ed memory by alloc_symbol(). No one will keep track of the
pointer of strdup'ed memory.sym->namespace still points to the NAMESPACE part. So, you can free it
with complicated code like this:free(sym->namespace - strlen(sym->name) - 1);
It complicates memory free.
To fix it elegantly, I swapped the order of the symbol and the
namespace as follows:__ksymtab_NAMESPACE.SYMBOL
then, simplified sym_extract_namespace() so that it allocates memory
only for the NAMESPACE part.I prefer this order because it is intuitive and also matches to major
languages. For example, NAMESPACE::NAME in C++, MODULE.NAME in Python.Reviewed-by: Matthias Maennich
Signed-off-by: Masahiro Yamada
Signed-off-by: Jessica Yu
01 Oct, 2019
1 commit
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Johannes Berg reports lots of modpost warnings on ARCH=um builds:
WARNING: "rename" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "lseek" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "ftruncate64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "getuid" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "lseek64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "unlink" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "pwrite64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "close" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "opendir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "pread64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "syscall" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "readdir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "readdir64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "futimes" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__lxstat" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "write" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "closedir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__xstat" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "fsync" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__lxstat64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__fxstat64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "telldir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "printf" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "readlink" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__sprintf_chk" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "link" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "rmdir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "fdatasync" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "truncate" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "statfs" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__errno_location" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__xmknod" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "open64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "truncate64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "open" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "read" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "chown" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "chmod" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "utime" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "fchmod" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "seekdir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "ioctl" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "dup2" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "statfs64" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "utimes" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "mkdir" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "fchown" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__guard" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "symlink" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "access" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "__stack_smash_handler" [vmlinux] is a static EXPORT_SYMBOLWhen you run "make", the modpost is run twice; before linking vmlinux,
and before building modules. All the warnings above are from the second
modpost.The offending symbols are defined not in vmlinux, but in the C library.
The first modpost is run against the relocatable vmlinux.o, and those
warnings are nicely suppressed because the SH_UNDEF entries from the
symbol table clear the ->is_static flag.The second modpost is run against the executable vmlinux (+ modules),
where those symbols have been resolved, but the definitions do not
exist.This commit fixes it in a straightforward way; suppress the static
EXPORT_SYMBOL warnings from "vmlinux".Without this commit, we see valid warnings twice anyway. For example,
ARCH=arm64 defconfig shows the following warning twice:WARNING: "HYPERVISOR_platform_op" [vmlinux] is a static EXPORT_SYMBOL_GPL
So, it is reasonable to suppress the second one.
Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions")
Reported-by: Johannes Berg
Signed-off-by: Masahiro Yamada
Tested-by: Johannes Berg
Tested-by: Denis Efremov
23 Sep, 2019
1 commit
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Pull modules updates from Jessica Yu:
"The main bulk of this pull request introduces a new exported symbol
namespaces feature. The number of exported symbols is increasingly
growing with each release (we're at about 31k exports as of 5.3-rc7)
and we currently have no way of visualizing how these symbols are
"clustered" or making sense of this huge export surface.Namespacing exported symbols allows kernel developers to more
explicitly partition and categorize exported symbols, as well as more
easily limiting the availability of namespaced symbols to other parts
of the kernel. For starters, we have introduced the USB_STORAGE
namespace to demonstrate the API's usage. I have briefly summarized
the feature and its main motivations in the tag below.Summary:
- Introduce exported symbol namespaces.
This new feature allows subsystem maintainers to partition and
categorize their exported symbols into explicit namespaces. Module
authors are now required to import the namespaces they need.Some of the main motivations of this feature include: allowing
kernel developers to better manage the export surface, allow
subsystem maintainers to explicitly state that usage of some
exported symbols should only be limited to certain users (think:
inter-module or inter-driver symbols, debugging symbols, etc), as
well as more easily limiting the availability of namespaced symbols
to other parts of the kernel.With the module import requirement, it is also easier to spot the
misuse of exported symbols during patch review.Two new macros are introduced: EXPORT_SYMBOL_NS() and
EXPORT_SYMBOL_NS_GPL(). The API is thoroughly documented in
Documentation/kbuild/namespaces.rst.- Some small code and kbuild cleanups here and there"
* tag 'modules-for-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: Remove leftover '#undef' from export header
module: remove unneeded casts in cmp_name()
module: move CONFIG_UNUSED_SYMBOLS to the sub-menu of MODULES
module: remove redundant 'depends on MODULES'
module: Fix link failure due to invalid relocation on namespace offset
usb-storage: export symbols in USB_STORAGE namespace
usb-storage: remove single-use define for debugging
docs: Add documentation for Symbol Namespaces
scripts: Coccinelle script for namespace dependencies.
modpost: add support for generating namespace dependencies
export: allow definition default namespaces in Makefiles or sources
module: add config option MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
modpost: add support for symbol namespaces
module: add support for symbol namespaces.
export: explicitly align struct kernel_symbol
module: support reading multiple values per modinfo tag
14 Sep, 2019
2 commits
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Use the __section() shorthand. This avoids escaping double-quotes,
and improves the readability.Signed-off-by: Masahiro Yamada
-
This makes *.mod.c much more readable. I confirmed depmod still
produced the same modules.dep file.Signed-off-by: Masahiro Yamada
10 Sep, 2019
2 commits
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This patch adds an option to modpost to generate a .ns_deps file
per module, containing the namespace dependencies for that module.E.g. if the linked module my-module.ko would depend on the symbol
myfunc.MY_NS in the namespace MY_NS, the my-module.ns_deps file created
by modpost would contain the entry MY_NS to express the namespace
dependency of my-module imposed by using the symbol myfunc.These files can subsequently be used by static analysis tools (like
coccinelle scripts) to address issues with missing namespace imports. A
later patch of this series will introduce such a script 'nsdeps' and a
corresponding make target to automatically add missing
MODULE_IMPORT_NS() definitions to the module's sources. For that it uses
the information provided in the generated .ns_deps files.Co-developed-by: Martijn Coenen
Signed-off-by: Martijn Coenen
Reviewed-by: Greg Kroah-Hartman
Signed-off-by: Matthias Maennich
Signed-off-by: Jessica Yu -
Add support for symbols that are exported into namespaces. For that,
extract any namespace suffix from the symbol name. In addition, emit a
warning whenever a module refers to an exported symbol without
explicitly importing the namespace that it is defined in. This patch
consistently adds the namespace suffix to symbol names exported into
Module.symvers.Example warning emitted by modpost in case of the above violation:
WARNING: module ums-usbat uses symbol usb_stor_resume from namespace
USB_STORAGE, but does not import it.Co-developed-by: Martijn Coenen
Signed-off-by: Martijn Coenen
Reviewed-by: Joel Fernandes (Google)
Reviewed-by: Greg Kroah-Hartman
Signed-off-by: Matthias Maennich
Signed-off-by: Jessica Yu
04 Sep, 2019
2 commits
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Add NOFAIL check for the strndup call, because the function
allocates memory and can return NULL. All calls to strdup in
modpost are checked with NOFAIL.Signed-off-by: Denis Efremov
Signed-off-by: Masahiro Yamada -
Since guid_t is the recommended data type for UUIDs in
kernel (and I guess uuid_le is meant to be ultimately
replaced with it), it should be made available here as
well.Signed-off-by: Heikki Krogerus
Signed-off-by: Masahiro Yamada
14 Aug, 2019
1 commit
-
This patch adds a check to warn about static EXPORT_SYMBOL* functions
during the modpost. In most of the cases, a static symbol marked for
exporting is an odd combination that should be fixed either by deleting
the exporting mark or by removing the static attribute and adding the
appropriate declaration to headers.This check could help to detect the following problems:
1. 550113d4e9f5 ("i2c: add newly exported functions to the header, too")
2. 54638c6eaf44 ("net: phy: make exported variables non-static")
3. 98ef2046f28b ("mm: remove the exporting of totalram_pages")
4. 73df167c819e ("s390/zcrypt: remove the exporting of ap_query_configuration")
5. a57caf8c527f ("sunrpc/cache: remove the exporting of cache_seq_next")
6. e4e4730698c9 ("crypto: skcipher - remove the exporting of skcipher_walk_next")
7. 14b4c48bb1ce ("gve: Remove the exporting of gve_probe")
8. 9b79ee9773a8 ("scsi: libsas: remove the exporting of sas_wait_eh")
9. ...The build time impact is very limited and is almost at the unnoticeable
level (< 1 sec).Acked-by: Emil Velikov
Signed-off-by: Denis Efremov
Signed-off-by: Masahiro Yamada
18 Jul, 2019
2 commits
-
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
-
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 $(MODVERDIR)
for every module it is building. Some post-processing steps read the
necessary information from *.mod files. This avoids descending into
directories again. This mechanism was introduced in 2003 or so.Later, commit 551559e13af1 ("kbuild: implement modules.order") added
modules.order. So, we can simply read it out to know all the modules
with directory paths. This is easier than parsing the first line of
*.mod files.$(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
$(MODVERDIR)/*.mod simultaneously.Non-unique module names are the source of all kind of troubles, hence
commit 3a48a91901c5 ("kbuild: check uniqueness of module names")
introduced a new checker script.However, it is still fragile in the build system point of view because
this race happens before scripts/modules-check.sh is invoked. If it
happens again, the modpost will emit unclear error messages.To fix this issue completely, create *.mod with full directory path
so that two threads never attempt to write to the same file.$(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
Acked-by: Nicolas Pitre
28 Mar, 2019
1 commit
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Fix commit 56067812d5b0 ("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: 56067812d5b0 ("kbuild: modversions: add infrastructure for emitting relative CRCs")
Signed-off-by: Fredrik Noring
Cc: stable@vger.kernel.org
Signed-off-by: Masahiro Yamada
14 Mar, 2019
1 commit
-
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
11 Mar, 2019
1 commit
-
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
...
08 Mar, 2019
2 commits
-
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
Signed-off-by: Mattias Jacobsson
Acked-by: Masahiro Yamada
Signed-off-by: Darren Hart (VMware) -
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
[dvhart: Move UUID_STRING_LEN define to this patch]
Signed-off-by: Darren Hart (VMware)
07 Mar, 2019
1 commit
-
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
Acked-by: Masahiro Yamada
Signed-off-by: Darren Hart (VMware)
01 Feb, 2019
1 commit
-
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
Reviewed-by: Daniel Thompson
Reviewed-by: Bhupesh Sharma
Signed-off-by: Jens Wiklander
09 Jan, 2019
1 commit
-
Commit
4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support")
replaced the RETPOLINE define with CONFIG_RETPOLINE checks. Remove the
remaining pieces.[ bp: Massage commit message. ]
Fixes: 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support")
Signed-off-by: WANG Chao
Signed-off-by: Borislav Petkov
Reviewed-by: Zhenzhong Duan
Reviewed-by: Masahiro Yamada
Cc: "H. Peter Anvin"
Cc: Andi Kleen
Cc: Andrew Morton
Cc: Andy Lutomirski
Cc: Arnd Bergmann
Cc: Daniel Borkmann
Cc: David Woodhouse
Cc: Geert Uytterhoeven
Cc: Jessica Yu
Cc: Jiri Kosina
Cc: Kees Cook
Cc: Konrad Rzeszutek Wilk
Cc: Luc Van Oostenryck
Cc: Michal Marek
Cc: Miguel Ojeda
Cc: Peter Zijlstra
Cc: Tim Chen
Cc: Vasily Gorbik
Cc: linux-kbuild@vger.kernel.org
Cc: srinivas.eeda@oracle.com
Cc: stable
Cc: x86-ml
Link: https://lkml.kernel.org/r/20181210163725.95977-1-chao.wang@ucloud.cn
01 Dec, 2018
7 commits
-
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
-
This will fit better in check_exports() than add_versions().
Signed-off-by: Masahiro Yamada
-
Probably, this is just a matter of the order of error/warning
messages. Merge the two for-loops.Signed-off-by: Masahiro Yamada
-
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
-
Use specific prototype instead of an opaque pointer so that the
compiler can catch function prototype mismatch.Signed-off-by: Masahiro Yamada
Reviewed-by: Mathieu Malaterre -
Commit e49ce14150c6 ("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 dd2a3acaecd7 ("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
Acked-by: Mathieu Malaterre -
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.html
https://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 2e3a10a1551d ("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 to restructure the code as an
additional pattern matching step inside secref_whitelist(), and
further improves the patch description.Signed-off-by: Paul Walmsley
Signed-off-by: Paul Walmsley
Acked-by: Sam Ravnborg
Signed-off-by: Masahiro Yamada
21 Nov, 2018
2 commits
-
Drop modpost command line switches that are no longer used by
makefile.modpost, upon request from Sam Ravnborg ,
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 a8773769d1a1 ("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
Signed-off-by: Paul Walmsley
Signed-off-by: Paul Walmsley
Acked-by: Sam Ravnborg
Signed-off-by: Masahiro Yamada -
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.0This 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
Signed-off-by: Masahiro Yamada
29 Oct, 2018
1 commit
-
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
28 Oct, 2018
1 commit
-
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
Signed-off-by: Masahiro Yamada
19 Oct, 2018
1 commit
-
Blackfin and metag were the only architectures that prefix symbols with
an underscore. They were removed by commit 4ba66a976072 ("arch: remove
blackfin port"), commit bb6fb6dfcc17 ("metag: Remove arch/metag/"),
respectively.It is no longer necessary to handle part of module device
table symbols.Signed-off-by: Masahiro Yamada
04 Oct, 2018
1 commit
-
… asm() related GCC inlining bugs
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>
22 Aug, 2018
1 commit
-
Fix missing error check for memory allocation functions in
scripts/mod/modpost.c.Fixes kernel bugzilla #200319:
https://bugzilla.kernel.org/show_bug.cgi?id=200319Signed-off-by: Randy Dunlap
Cc: Yuexing Wang
Signed-off-by: Masahiro Yamada
19 Aug, 2018
1 commit
-
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
...