This change adds the CONFIG_CFI_CLANG option, CFI error handling,
and a faster look-up table for cross module CFI checks.
Bug: 145210207
Change-Id: I118303de50114ca6f85d89a7d69c5cbc47e2f5c0
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Similarly to the CC_IS_CLANG config, add LD_IS_LLD to simplify feature
selection based on the linker.
Bug: 145210207
Change-Id: I097c52899dcf9829eb0e1ea89211b17972301c1a
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This change adds generic support for Clang's Shadow Call Stack,
which uses a shadow stack to protect return addresses from being
overwritten by an attacker. Details are available here:
https://clang.llvm.org/docs/ShadowCallStack.html
Note that security guarantees in the kernel differ from the
ones documented for user space. The kernel must store addresses
of shadow stacks used by other tasks and interrupt handlers in
memory, which means an attacker capable reading and writing
arbitrary memory may be able to locate them and hijack control
flow by modifying shadow stacks that are not currently in use.
Bug: 145210207
Change-Id: I2a8ba6a3decac50c169731c3121c9dcab96621d2
(am from https://lore.kernel.org/patchwork/patch/1149054/)
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This reverts commit 3fde1dfb00.
Revert to the upstream version by reinstating the original
modules-for-v5.4 merge.
Bug: 142892219
Bug: 144336692
Change-Id: I3871c67dd3cba0a5b9b2e1a87be8653a14cb9de5
Signed-off-by: Matthias Maennich <maennich@google.com>
Fix missing dependency for CONFIG_VIDEOBUF2_CORE for
'allmodconfig' builds. Since CONFIG_MEDIA_SUPPORT is
always selected, drop it from gki_defconfig
Fixes: 649238947d ("ANDROID: init: GKI: enable hidden configs
for media")
Test: successful 'allmodconfig' build
Change-Id: I1dd5ff154c1aeb90457c23dc233cb32595bd9bed
Signed-off-by: Todd Kjos <tkjos@google.com>
Add hidden configs to GKI_HACKS_to_fIX so they are
enabled for loadable media modules build out-of-tree
Bug: 142892658
Test: Built for arm64/x86_64. Boot on cuttlefish
Change-Id: I137a89f69822332324a1f4a3a1150be9cd66709d
Signed-off-by: Todd Kjos <tkjos@google.com>
SND_PCM_ELD is used by DRM drivers for HDMI audio,
so add it to the HIDDEN_DRM configs.
Bug: 142268770
Change-Id: I914beef34b2cf5174da76a5d1a4d443117f1b687
Signed-off-by: John Stultz <john.stultz@linaro.org>
This reverts commit e070355664, reversing
changes made to 8808cf8cbc.
Introducing symbol-namespaces into the kernel has caused issues with
respect to the ABI checker. Hence, revert the changes until a valid
fix is available. The revert was done based off of 5.4-rc1.
Change-Id: I529ced269661f457ce667a76eb383843002f0a7d
Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>
To make the 5.4-rc1 merge easier, merge at a prerelease point in time
before the final release happens.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: If613d657fd0abf9910c5bf3435a745f01b89765e
Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.
From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.
The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.
There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/
- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.
The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.
The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:
lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.
This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.
New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.
The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.
Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"
* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
Pull integrity updates from Mimi Zohar:
"The major feature in this time is IMA support for measuring and
appraising appended file signatures. In addition are a couple of bug
fixes and code cleanup to use struct_size().
In addition to the PE/COFF and IMA xattr signatures, the kexec kernel
image may be signed with an appended signature, using the same
scripts/sign-file tool that is used to sign kernel modules.
Similarly, the initramfs may contain an appended signature.
This contained a lot of refactoring of the existing appended signature
verification code, so that IMA could retain the existing framework of
calculating the file hash once, storing it in the IMA measurement list
and extending the TPM, verifying the file's integrity based on a file
hash or signature (eg. xattrs), and adding an audit record containing
the file hash, all based on policy. (The IMA support for appended
signatures patch set was posted and reviewed 11 times.)
The support for appended signature paves the way for adding other
signature verification methods, such as fs-verity, based on a single
system-wide policy. The file hash used for verifying the signature and
the signature, itself, can be included in the IMA measurement list"
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: ima_api: Use struct_size() in kzalloc()
ima: use struct_size() in kzalloc()
sefltest/ima: support appended signatures (modsig)
ima: Fix use after free in ima_read_modsig()
MODSIGN: make new include file self contained
ima: fix freeing ongoing ahash_request
ima: always return negative code for error
ima: Store the measurement again when appraising a modsig
ima: Define ima-modsig template
ima: Collect modsig
ima: Implement support for module-style appended signatures
ima: Factor xattr_verify() out of ima_appraise_measurement()
ima: Add modsig appraise_type option for module-style appended signatures
integrity: Select CONFIG_KEYS instead of depending on it
PKCS#7: Introduce pkcs7_get_digest()
PKCS#7: Refactor verify_pkcs7_signature()
MODSIGN: Export module signature definitions
ima: initialize the "template" field with the default template
Replace open-coded bitmap array initialization of init_mm.cpu_bitmask with
neat CPU_BITS_NONE macro.
And, since init_mm.cpu_bitmask is statically set to zero, there is no way
to clear it again in start_kernel().
Link: http://lkml.kernel.org/r/1565703815-8584-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem
cache for page table allocations on several architectures that do not use
PAGE_SIZE tables for one or more levels of the page table hierarchy.
Most architectures do not implement these functions and use __weak default
NOP implementation of pgd_cache_init(). Since there is no such default
for pgtable_cache_init(), its empty stub is duplicated among most
architectures.
Rename the definitions of pgd_cache_init() to pgtable_cache_init() and
drop empty stubs of pgtable_cache_init().
Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Will Deacon <will@kernel.org> [arm64]
Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently kmemleak uses a static early_log buffer to trace all memory
allocation/freeing before the slab allocator is initialised. Such early
log is replayed during kmemleak_init() to properly initialise the kmemleak
metadata for objects allocated up that point. With a memory pool that
does not rely on the slab allocator, it is possible to skip this early log
entirely.
In order to remove the early logging, consider kmemleak_enabled == 1 by
default while the kmem_cache availability is checked directly on the
object_cache and scan_area_cache variables. The RCU callback is only
invoked after object_cache has been initialised as we wouldn't have any
concurrent list traversal before this.
In order to reduce the number of callbacks before kmemleak is fully
initialised, move the kmemleak_init() call to mm_init().
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: remove WARN_ON(), per Catalin]
Link: http://lkml.kernel.org/r/20190812160642.52134-4-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To make the 5.4-rc1 merge easier, merge at a prerelease point in time
before the final release happens.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I29b683c837ed1a3324644dbf9bf863f30740cd0b
Summary of modules changes for the 5.4 merge window:
- 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.
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Merge tag 'modules-for-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
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
- virtio support
- Fixes for our new time travel mode
- Various improvements to make lockdep and kasan work better
- SPDX header updates
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Merge tag 'for-linus-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
- virtio support
- fixes for our new time travel mode
- various improvements to make lockdep and kasan work better
- SPDX header updates
* tag 'for-linus-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (25 commits)
um: irq: Fix LAST_IRQ usage in init_IRQ()
um: Add SPDX headers for files in arch/um/include
um: Add SPDX headers for files in arch/um/os-Linux
um: Add SPDX headers to files in arch/um/kernel/
um: Add SPDX headers for files in arch/um/drivers
um: virtio: Implement VHOST_USER_PROTOCOL_F_REPLY_ACK
um: virtio: Implement VHOST_USER_PROTOCOL_F_SLAVE_REQ
um: drivers: Add virtio vhost-user driver
um: Use real DMA barriers
um: Don't use generic barrier.h
um: time-travel: Restrict time update in IRQ handler
um: time-travel: Fix periodic timers
um: Enable CONFIG_CONSTRUCTORS
um: Place (soft)irq text with macros
um: Fix VDSO compiler warning
um: Implement TRACE_IRQFLAGS_SUPPORT
um: Remove misleading #define ARCh_IRQ_ENABLED
um: Avoid using uninitialized regs
um: Remove sig_info[SIGALRM]
um: Error handling fixes in vector drivers
...
gcc 9+ (and gcc 8.3, 7.5) provides a way to override the otherwise
crude heuristic that gcc uses to estimate the size of the code
represented by an asm() statement. From the gcc docs
If you use 'asm inline' instead of just 'asm', then for inlining
purposes the size of the asm is taken as the minimum size, ignoring
how many instructions GCC thinks it is.
For compatibility with older compilers, we obviously want a
#if [understands asm inline]
#define asm_inline asm inline
#else
#define asm_inline asm
#endif
But since we #define the identifier inline to attach some attributes,
we have to use an alternate spelling of that keyword. gcc provides
both __inline__ and __inline, and we currently #define both to inline,
so they all have the same semantics. We have to free up one of
__inline__ and __inline, and the latter is by far the easiest.
The two x86 changes cause smaller code gen differences than I'd
expect, but I think we do want the asm_inline thing available sooner
or later, so this is just to get the ball rolling.
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Merge tag 'compiler-attributes-for-linus-v5.4' of git://github.com/ojeda/linux
Pull asm inline support from Miguel Ojeda:
"Make use of gcc 9's "asm inline()" (Rasmus Villemoes):
gcc 9+ (and gcc 8.3, 7.5) provides a way to override the otherwise
crude heuristic that gcc uses to estimate the size of the code
represented by an asm() statement. From the gcc docs
If you use 'asm inline' instead of just 'asm', then for inlining
purposes the size of the asm is taken as the minimum size, ignoring
how many instructions GCC thinks it is.
For compatibility with older compilers, we obviously want a
#if [understands asm inline]
#define asm_inline asm inline
#else
#define asm_inline asm
#endif
But since we #define the identifier inline to attach some attributes,
we have to use an alternate spelling of that keyword. gcc provides
both __inline__ and __inline, and we currently #define both to inline,
so they all have the same semantics.
We have to free up one of __inline__ and __inline, and the latter is
by far the easiest.
The two x86 changes cause smaller code gen differences than I'd
expect, but I think we do want the asm_inline thing available sooner
or later, so this is just to get the ball rolling"
* tag 'compiler-attributes-for-linus-v5.4' of git://github.com/ojeda/linux:
x86: bug.h: use asm_inline in _BUG_FLAGS definitions
x86: alternative.h: use asm_inline for all alternative variants
compiler-types.h: add asm_inline definition
compiler_types.h: don't #define __inline
lib/zstd/mem.h: replace __inline by inline
staging: rtl8723bs: replace __inline by inline
This merges Linus's tree as of commit b41dae061b ("Merge tag
'xfs-5.4-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux")
into android-mainline.
This "early" merge makes it easier to test and handle merge conflicts
instead of having to wait until the "end" of the merge window and handle
all 10000+ commits at once.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I6bebf55e5e2353f814e3c87f5033607b1ae5d812
In embedded environments the requirements are to be able to pick and
chose which features one requires built into the kernel. If an
embedded environment wants to supports loading modules that have been
kbuilt out of tree, there is a need to enable hidden configurations
for legacy wireless core features to provide the API surface for
them to load.
Introduce CONFIG_GKI_LEGACY_WEXT_ALLCONFIG to select all legacy wireless
extension core features by activating in turn all the associated
hidden configuration options, without having to specifically select
any wireless module(s).
(rejected upstream commit url https://lkml.org/lkml/2019/9/6/878)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 140250271
Change-Id: Ie40e656d87ce21ae82f04ffe8dae2f0efab88a2e
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination
- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule
- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build
in unclean source tree
- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_<basetarget>.o to take the relative path to $(obj)
instead of the basename
- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols
- misc cleanups
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Merge tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination
- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule
- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build in
unclean source tree
- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_<basetarget>.o to take the relative path to $(obj)
instead of the basename
- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols
- misc cleanups
* tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits)
genksyms: convert to SPDX License Identifier for lex.l and parse.y
modpost: use __section in the output to *.mod.c
modpost: use MODULE_INFO() for __module_depends
export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
export.h: remove defined(__KERNEL__), which is no longer needed
kbuild: allow Clang to find unused static inline functions for W=1 build
kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
kbuild: refactor scripts/Makefile.extrawarn
merge_config.sh: ignore unwanted grep errors
kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)
modpost: add NOFAIL to strndup
modpost: add guid_t type definition
kbuild: add $(BASH) to run scripts with bash-extension
kbuild: remove ARCH_{CPP,A,C}FLAGS
kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC
kbuild: Do not enable -Wimplicit-fallthrough for clang for now
kbuild: clean up subdir-ymn calculation in Makefile.clean
kbuild: remove unneeded '+' marker from cmd_clean
kbuild: remove clean-dirs syntax
kbuild: check clean srctree even earlier
...
Add hidden configs to GKI_HACKS_TO_FIX so they are
enabled for loadable GPIO modules built out-of-tree
Bug: 141266428
Change-Id: Ie6e79921df67e86783f04cb869604c988656a034
Signed-off-by: Todd Kjos <tkjos@google.com>
Add hidden configs to GKI_HACKS_TO_FIX so they are
enabled for loadable SND_SOC modules built out-of-tree
Bug: 141266428
Change-Id: I4782b5bb401a76c647bac41258c1371762dace1c
Signed-off-by: Todd Kjos <tkjos@google.com>
Add hidden configs to GKI_HACKS_TO_FIX so they are
enabled for loadable regmap modules built out-of-tree.
Bug: 141266428
Change-Id: I1dedb1fd6e26e36c12b28fcbbf0302f074547101
Signed-off-by: Todd Kjos <tkjos@google.com>
Add hidden configs to GKI_HACKS_TO_FIX so they
are enabled for loadable DRM modules built
out-of-tree.
Bug: 141266428
Change-Id: Ibeda203afa54edc4f9a1daec9b4e8a928eb934fb
Signed-off-by: Todd Kjos <tkjos@google.com>
Add CONFIG_GKI_HACKS_TO_FIX as a mechanism to force
hidden configs to be selected for modules that will be built
separately. Also used to select drivers that need to be
modularized.
As these issues are resolved upstream, the configs should
be removed from GKI_HACKS_TO_FIX
Bug: 141266428
Change-Id: Ic8b2a17cd3a389ac5ef999c8c79b5b5dfee73c8a
Signed-off-by: Todd Kjos <tkjos@google.com>
Pull misc mount API conversions from Al Viro:
"Conversions to new API for shmem and friends and for mount_mtd()-using
filesystems.
As for the rest of the mount API conversions in -next, some of them
belong in the individual trees (e.g. binderfs one should definitely go
through android folks, after getting redone on top of their changes).
I'm going to drop those and send the rest (trivial ones + stuff ACKed
by maintainers) in a separate series - by that point they are
independent from each other.
Some stuff has already migrated into individual trees (NFS conversion,
for example, or FUSE stuff, etc.); those presumably will go through
the regular merges from corresponding trees."
* 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: Make fs_parse() handle fs_param_is_fd-type params better
vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API
shmem_parse_one(): switch to use of fs_parse()
shmem_parse_options(): take handling a single option into a helper
shmem_parse_options(): don't bother with mpol in separate variable
shmem_parse_options(): use a separate structure to keep the results
make shmem_fill_super() static
make ramfs_fill_super() static
devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()
vfs: Convert squashfs to use the new mount API
mtd: Kill mount_mtd()
vfs: Convert jffs2 to use the new mount API
vfs: Convert cramfs to use the new mount API
vfs: Convert romfs to use the new mount API
vfs: Add a single-or-reconfig keying to vfs_get_super()
Pull core timer updates from Thomas Gleixner:
"Timers and timekeeping updates:
- A large overhaul of the posix CPU timer code which is a preparation
for moving the CPU timer expiry out into task work so it can be
properly accounted on the task/process.
An update to the bogus permission checks will come later during the
merge window as feedback was not complete before heading of for
travel.
- Switch the timerqueue code to use cached rbtrees and get rid of the
homebrewn caching of the leftmost node.
- Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a
single function
- Implement the separation of hrtimers to be forced to expire in hard
interrupt context even when PREEMPT_RT is enabled and mark the
affected timers accordingly.
- Implement a mechanism for hrtimers and the timer wheel to protect
RT against priority inversion and live lock issues when a (hr)timer
which should be canceled is currently executing the callback.
Instead of infinitely spinning, the task which tries to cancel the
timer blocks on a per cpu base expiry lock which is held and
released by the (hr)timer expiry code.
- Enable the Hyper-V TSC page based sched_clock for Hyper-V guests
resulting in faster access to timekeeping functions.
- Updates to various clocksource/clockevent drivers and their device
tree bindings.
- The usual small improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
posix-cpu-timers: Fix permission check regression
posix-cpu-timers: Always clear head pointer on dequeue
hrtimer: Add a missing bracket and hide `migration_base' on !SMP
posix-cpu-timers: Make expiry_active check actually work correctly
posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build
tick: Mark sched_timer to expire in hard interrupt context
hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD
x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n
posix-cpu-timers: Utilize timerqueue for storage
posix-cpu-timers: Move state tracking to struct posix_cputimers
posix-cpu-timers: Deduplicate rlimit handling
posix-cpu-timers: Remove pointless comparisons
posix-cpu-timers: Get rid of 64bit divisions
posix-cpu-timers: Consolidate timer expiry further
posix-cpu-timers: Get rid of zero checks
rlimit: Rewrite non-sensical RLIMIT_CPU comment
posix-cpu-timers: Respect INFINITY for hard RTTIME limit
posix-cpu-timers: Switch thread group sampling to array
posix-cpu-timers: Restructure expiry array
posix-cpu-timers: Remove cputime_expires
...
Pull scheduler updates from Ingo Molnar:
- MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.
As perf and the scheduler is getting bigger and more complex,
document the status quo of current responsibilities and interests,
and spread the review pain^H^H^H^H fun via an increase in the Cc:
linecount generated by scripts/get_maintainer.pl. :-)
- Add another series of patches that brings the -rt (PREEMPT_RT) tree
closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
into a new CONFIG_PREEMPTION category that will allow the eventual
introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
to go though.
- Extend the CPU cgroup controller with uclamp.min and uclamp.max to
allow the finer shaping of CPU bandwidth usage.
- Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).
- Improve the behavior of high CPU count, high thread count
applications running under cpu.cfs_quota_us constraints.
- Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.
- Improve CPU isolation housekeeping CPU allocation NUMA locality.
- Fix deadline scheduler bandwidth calculations and logic when cpusets
rebuilds the topology, or when it gets deadline-throttled while it's
being offlined.
- Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
setscheduler() system calls without creating global serialization.
Add new synchronization between cpuset topology-changing events and
the deadline acceptance tests in setscheduler(), which were broken
before.
- Rework the active_mm state machine to be less confusing and more
optimal.
- Rework (simplify) the pick_next_task() slowpath.
- Improve load-balancing on AMD EPYC systems.
- ... and misc cleanups, smaller fixes and improvements - please see
the Git log for more details.
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
sched/psi: Correct overly pessimistic size calculation
sched/fair: Speed-up energy-aware wake-ups
sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
sched/uclamp: Update CPU's refcount on TG's clamp changes
sched/uclamp: Use TG's clamps to restrict TASK's clamps
sched/uclamp: Propagate system defaults to the root group
sched/uclamp: Propagate parent clamps
sched/uclamp: Extend CPU's cgroup controller
sched/topology: Improve load balancing on AMD EPYC systems
arch, ia64: Make NUMA select SMP
sched, perf: MAINTAINERS update, add submaintainers and reviewers
sched/fair: Use rq_lock/unlock in online_fair_sched_group
cpufreq: schedutil: fix equation in comment
sched: Rework pick_next_task() slow-path
sched: Allow put_prev_task() to drop rq->lock
sched/fair: Expose newidle_balance()
sched: Add task_struct pointer to sched_class::set_curr_task
sched: Rework CPU hotplug task selection
sched/{rt,deadline}: Fix set_next_task vs pick_next_task
sched: Fix kerneldoc comment for ia64_set_curr_task
...
We do need to call the constructors for *modules*, and
at least for KASAN in the future, we must call even the
kernel constructors only later when the kernel has been
initialized.
Instead of relying on libc to call them, emit an empty
section for libc and let the kernel's CONSTRUCTORS code
do the rest of the job.
Tested that it indeed doesn't work in modules, and does
work after the fixes in both, with a few functions with
__attribute__((constructor)) in both dynamic and static
builds.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This adds an asm_inline macro which expands to "asm inline" [1] when
the compiler supports it. This is currently gcc 9.1+, gcc 8.3
and (once released) gcc 7.5 [2]. It expands to just "asm" for other
compilers.
Using asm inline("foo") instead of asm("foo") overrules gcc's
heuristic estimate of the size of the code represented by the asm()
statement, and makes gcc use the minimum possible size instead. That
can in turn affect gcc's inlining decisions.
I wasn't sure whether to make this a function-like macro or not - this
way, it can be combined with volatile as
asm_inline volatile()
but perhaps we'd prefer to spell that
asm_inline_volatile()
anyway.
The Kconfig logic is taken from an RFC patch by Masahiro Yamada [3].
[1] Technically, asm __inline, since both inline and __inline__
are macros that attach various attributes, making gcc barf if one
literally does "asm inline()". However, the third spelling __inline is
available for referring to the bare keyword.
[2] https://lore.kernel.org/lkml/20190907001411.GG9749@gate.crashing.org/
[3] https://lore.kernel.org/lkml/1544695154-15250-1-git-send-email-yamada.masahiro@socionext.com/
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Convert the ramfs, shmem, tmpfs, devtmpfs and rootfs filesystems to the new
internal mount API as the old one will be obsoleted and removed. This
allows greater flexibility in communication of mount parameters between
userspace, the VFS and the filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Note that tmpfs is slightly tricky as it can contain embedded commas, so it
can't be trivially split up using strsep() to break on commas in
generic_parse_monolithic(). Instead, tmpfs has to supply its own generic
parser.
However, if tmpfs changes, then devtmpfs and rootfs, which are wrappers
around tmpfs or ramfs, must change too - and thus so must ramfs, so these
had to be converted also.
[AV: rewritten]
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hugh Dickins <hughd@google.com>
cc: linux-mm@kvack.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When CONFIG_MODULES is disabled, CONFIG_UNUSED_SYMBOLS is pointless,
thus it should be invisible.
Instead of adding "depends on MODULES", I moved it to the sub-menu
"Enable loadable module support", which is a better fit. I put it
close to TRIM_UNUSED_KSYMS because it depends on !UNUSED_SYMBOLS.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
These are located in the 'if MODULES' ... 'endif' block.
Remove the redundant dependencies.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
If MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS is enabled (default=n), the
requirement for modules to import all namespaces that are used by
the module is relaxed.
Enabling this option effectively allows (invalid) modules to be loaded
while only a warning is emitted.
Disabling this option keeps the enforcement at module loading time and
loading is denied if the module's imports are not satisfactory.
Reviewed-by: Martijn Coenen <maco@android.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
arch/arc/Makefile overrides -O2 with -O3. This is the only user of
ARCH_CFLAGS. There is no user of ARCH_CPPFLAGS or ARCH_AFLAGS.
My plan is to remove ARCH_{CPP,A,C}FLAGS after refactoring the ARC
Makefile.
Currently, ARC has no way to enable -Wmaybe-uninitialized because both
-O3 and -Os disable it. Enabling it will be useful for compile-testing.
This commit allows allmodconfig (, which defaults to -O2) to enable it.
Add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3=y to all the defconfig files
in arch/arc/configs/ in order to keep the current config settings.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
The cgroup CPU bandwidth controller allows to assign a specified
(maximum) bandwidth to the tasks of a group. However this bandwidth is
defined and enforced only on a temporal base, without considering the
actual frequency a CPU is running on. Thus, the amount of computation
completed by a task within an allocated bandwidth can be very different
depending on the actual frequency the CPU is running that task.
The amount of computation can be affected also by the specific CPU a
task is running on, especially when running on asymmetric capacity
systems like Arm's big.LITTLE.
With the availability of schedutil, the scheduler is now able
to drive frequency selections based on actual task utilization.
Moreover, the utilization clamping support provides a mechanism to
bias the frequency selection operated by schedutil depending on
constraints assigned to the tasks currently RUNNABLE on a CPU.
Giving the mechanisms described above, it is now possible to extend the
cpu controller to specify the minimum (or maximum) utilization which
should be considered for tasks RUNNABLE on a cpu.
This makes it possible to better defined the actual computational
power assigned to task groups, thus improving the cgroup CPU bandwidth
controller which is currently based just on time constraints.
Extend the CPU controller with a couple of new attributes uclamp.{min,max}
which allow to enforce utilization boosting and capping for all the
tasks in a group.
Specifically:
- uclamp.min: defines the minimum utilization which should be considered
i.e. the RUNNABLE tasks of this group will run at least at a
minimum frequency which corresponds to the uclamp.min
utilization
- uclamp.max: defines the maximum utilization which should be considered
i.e. the RUNNABLE tasks of this group will run up to a
maximum frequency which corresponds to the uclamp.max
utilization
These attributes:
a) are available only for non-root nodes, both on default and legacy
hierarchies, while system wide clamps are defined by a generic
interface which does not depends on cgroups. This system wide
interface enforces constraints on tasks in the root node.
b) enforce effective constraints at each level of the hierarchy which
are a restriction of the group requests considering its parent's
effective constraints. Root group effective constraints are defined
by the system wide interface.
This mechanism allows each (non-root) level of the hierarchy to:
- request whatever clamp values it would like to get
- effectively get only up to the maximum amount allowed by its parent
c) have higher priority than task-specific clamps, defined via
sched_setattr(), thus allowing to control and restrict task requests.
Add two new attributes to the cpu controller to collect "requested"
clamp values. Allow that at each non-root level of the hierarchy.
Keep it simple by not caring now about "effective" values computation
and propagation along the hierarchy.
Update sysctl_sched_uclamp_handler() to use the newly introduced
uclamp_mutex so that we serialize system default updates with cgroup
relate updates.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-2-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CONFIG_CC_OPTIMIZE_FOR_SIZE was originally an independent boolean
option, but commit 877417e6ff ("Kbuild: change CC_OPTIMIZE_FOR_SIZE
definition") turned it into a choice between _PERFORMANCE and _SIZE.
The phrase "If unsure, say N." sounds like an independent option.
Reword the help text to make it appropriate for the choice menu.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
