x86/vdso: Prepare introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
To prepare for the rework of the data structures, replace the struct
vdso_time_data pointer with a struct vdso_clock pointer where applicable.
time/namespace: Prepare introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
To prepare for the rework of the data structures, replace the struct
vdso_time_data pointer with a struct vdso_clock pointer where applicable.
vdso/namespace: Rename timens_setup_vdso_data() to reflect new vdso_clock struct
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
For time namespaces, vdso_time_data needs to be set up. But only the clock
related part of the vdso_data thats requires this setup. To reflect the
future struct vdso_clock, rename timens_setup_vdso_data() to
timns_setup_vdso_clock_data().
vdso/vsyscall: Prepare introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
To prepare for the rework of the data structures, replace the struct
vdso_time_data pointer with a struct vdso_clock pointer where applicable.
vdso/gettimeofday: Prepare helper functions for introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
To prepare for the rework of the data structures, replace the struct
vdso_time_data pointer argument of the helper functions with struct
vdso_clock pointer where applicable.
vdso/gettimeofday: Prepare do_coarse_timens() for introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
Prepare for the rework of these structures by adding a struct vdso_clock
pointer argument to do_coarse_time_ns(), and replace the struct
vdso_time_data pointer with the new pointer argument where applicable.
vdso/gettimeofday: Prepare do_coarse() for introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
Prepare for the rework of these structures by adding a struct vdso_clock
pointer argument to do_coarse(), and replace the struct vdso_time_data
pointer with the new pointer argument where applicable.
vdso/gettimeofday: Prepare do_hres_timens() for introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
Prepare for the rework of these structures by adding a struct vdso_clock
pointer argument to do_hres_timens(), and replace the struct vdso_time_data
pointer with the new pointer argument where applicable.
vdso/gettimeofday: Prepare do_hres() for introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
Prepare for the rework of these structures by adding a struct vdso_clock
pointer argument to do_hres(), and replace the struct vdso_time_data
pointer with the new pointer argument where applicable.
vdso/gettimeofday: Prepare introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
Prepare all functions which need the pointer to the vdso_clock array to
work correctly after introducing the new struct. Where applicable, replace
the struct vdso_time_data pointer by a struct vdso_clock pointer.
vdso/helpers: Prepare introduction of struct vdso_clock
To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be an array of VDSO clocks. For now,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.
Prepare all functions which need the pointer to the vdso_clock array to
work well after the structures get reworked. Replace the struct vdso_time_data
pointer with a struct vdso_clock pointer where applicable.
vdso/datapage: Define vdso_clock to prepare for multiple PTP clocks
Multiple PTP clocks, which are independent of timekeeping, are required for
systems, which utilize PTP for synchronizing e.g. automation systems
independent of clock TAI.
PTP clocks are slow to access, but applications require fast access to the
relevant time similar to the regular timekeeping relevant clocks.
To prepare for that the VDSO data representation must be reworked. For
transition to the new structure of the vdso, add a define which maps
vdso_clock to vdso_data. This will be removed when all users are updated
step by step.
vdso_time_data is not cacheline aligned at the moment. When instantiating
an array, the start of the second array member is not cache line aligned.
This increases the number of the required cache lines which needs to be
read when handling e.g. CLOCK_MONOTONIC_RAW, because the data spawns an
extra cache line if the previous data does not end at a cache line
boundary.
Therefore make struct vdso_time_data cacheline aligned.
asm/cache.h can be used during the vDSO build through vdso/cache.h.
Not all definitions in it are compatible with the vDSO, especially the
compat vDSO.
Hide the more complex definitions from the vDSO build.
The vDSO implementation can only include headers from the vdso/
namespace. To enable the usage of ____cacheline_aligned from
the vDSO, move it and its dependencies into a new header vdso/cache.h.
Keep compatibility by including vdso/cache.h from linux/cache.h.
Thomas Weißschuh [Wed, 26 Feb 2025 11:44:55 +0000 (12:44 +0100)]
selftests: vDSO: vdso_standalone_test_x86: Switch to nolibc
vdso_standalone_test_x86 provides its own ASM syscall wrappers and
_start() implementation. The in-tree nolibc library already provides
this functionality for multiple architectures. By making use of nolibc,
the standalone testcase can be built from the exact same codebase as the
non-standalone version.
Thomas Weißschuh [Wed, 26 Feb 2025 11:44:52 +0000 (12:44 +0100)]
selftests: vDSO: parse_vdso: Test __SIZEOF_LONG__ instead of ULONG_MAX
According to limits.h(2) ULONG_MAX is only guaranteed to expand to an
expression, not a symbolic constant which can be evaluated by the
preprocessor.
Specifically the definition of ULONG_MAX from nolibc can not be evaluated
by the preprocessor. To provide compatibility with nolibc, check with
__SIZEOF_LONG__ instead, with is provided directly by the preprocessor
and therefore always a symbolic constant.
Thomas Weißschuh [Wed, 26 Feb 2025 11:44:49 +0000 (12:44 +0100)]
selftests: vDSO: vdso_standalone_test_x86: Use vdso_init_form_sysinfo_ehdr
vdso_standalone_test_x86 is the only user of vdso_init_from_auxv().
Instead of combining the parsing the aux vector with the parsing of the
vDSO, split them apart into getauxval() and the regular
vdso_init_from_sysinfo_ehdr().
The implementation of getauxval() is taken from
tools/include/nolibc/stdlib.h.
Thomas Weißschuh [Wed, 26 Feb 2025 11:44:47 +0000 (12:44 +0100)]
selftests: Add headers target
Some selftests need access to a full UAPI headers tree, for example when
building with nolibc which heavily relies on UAPI headers.
A reference to such a tree is available in the KHDR_INCLUDES variable,
but there is currently no way to populate such a tree automatically.
Provide a target that the tests can depend on to get access to usable
UAPI headers.
vdso: Remove remnants of architecture-specific time storage
All users of the time releated parts of the vDSO are now using the generic
storage implementation. Remove the therefore unnecessary compatibility
accessor functions and symbols.
The values are not used anymore.
Also the sanity checks performed by vdso2c can never trigger as they
only validate invariants already enforced by the linker script.
x86/vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
This switch also moves the random state data out of the time data page.
The currently used hardcoded __VDSO_RND_DATA_OFFSET does not take into
account changes to the time data page layout.
powerpc/vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-14-13a4669dfc8c@linutronix.de
MIPS: vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
s390/vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
Co-developed-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/all/20250204-vdso-store-rng-v3-12-13a4669dfc8c@linutronix.de
arm: vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
LoongArch: vDSO: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
riscv: vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
arm64: vdso: Switch to generic storage implementation
The generic storage implementation provides the same features as the
custom one. However it can be shared between architectures, making
maintenance easier.
This switch also moves the random state data out of the time data page.
The currently used hardcoded __VDSO_RND_DATA_OFFSET does not take into
account changes to the time data page layout.
vdso: Add generic architecture-specific data storage
Some architectures need to expose architecture-specific data to the vDSO.
Enable the generic vDSO storage mechanism to both store and map this
data. Some architectures require more than a single page, like LoongArch,
so prepare for that usecase, too.
Extend the generic vDSO data storage with a page for the random state data.
The random state data is stored in a dedicated page, as the existing
storage page is only meant for time-related, time-namespace-aware data.
This simplifies to access logic to not need to handle time namespaces
anymore and also frees up more space in the time-related page.
In case further generic vDSO data store is required it can be added to
the random state page.
Historically each architecture defined their own way to store the vDSO
data page. Add a generic mechanism to provide storage for that page.
Furthermore this generic storage will be extended to also provide
uniform storage for *non*-time-related data, like the random state or
architecture-specific data. These will have their own pages and data
structures, so rename 'vdso_data' into 'vdso_time_data' to make that
split clear from the name.
Also introduce a new consistent naming scheme for the symbols related to
the vDSO, which makes it clear if the symbol is accessible from
userspace or kernel space and the type of data behind the symbol.
The generic fault handler contains an optimization to prefault the vvar
page when the timens page is accessed. This was lifted from s390 and x86.
As the Makefile is included into other Makefiles it can not be used to
define objects to be built from the current source directory.
However the generic datastore will introduce such a local source file.
Rename the included Makefile so it is clear how it is to be used and to
make room for a regular Makefile in lib/vdso/.
The vDSO implementation can only include headers from the vdso/
namespace. To enable the usage of the ALIGN() macro from the vDSO, move
linux/align.h to vdso/align.h wholly.
As the only dependency linux/const.h is only a wrapper around
vdso/const.h anyways adapt that dependency.
Also provide a compatibility wrapper linux/align.h.
x86/vdso: Fix latent bug in vclock_pages calculation
The vclock pages are *after* the non-vclock pages. Currently there are both
two vclock and two non-vclock pages so the existing logic works by
accident. As soon as the number of pages changes it will break however.
This will be the case with the introduction of the generic vDSO data
storage.
Use a macro to keep the calculation understandable and in sync between
the linker script and mapping code.
Linus Torvalds [Sun, 9 Feb 2025 18:05:32 +0000 (10:05 -0800)]
Merge tag 'kbuild-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- Suppress false-positive -Wformat-{overflow,truncation}-non-kprintf
warnings regardless of the W= option
- Avoid CONFIG_TRIM_UNUSED_KSYMS dropping symbols passed to symbol_get()
- Fix a build regression of the Debian linux-headers package
* tag 'kbuild-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: install-extmod-build: add missing quotation marks for CC variable
kbuild: fix misspelling in scripts/Makefile.lib
kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS
scripts/Makefile.extrawarn: Do not show clang's non-kprintf warnings at W=1
Linus Torvalds [Sun, 9 Feb 2025 17:47:06 +0000 (09:47 -0800)]
Merge tag 'pm-6.14-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"Fix a recently introduced kernel crash due to a NULL pointer
dereference during system-wide suspend (Rafael Wysocki)"
* tag 'pm-6.14-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: sleep: core: Restrict power.set_active propagation
Linus Torvalds [Sun, 9 Feb 2025 17:41:38 +0000 (09:41 -0800)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Correctly clean the BSS to the PoC before allowing EL2 to access it
on nVHE/hVHE/protected configurations
- Propagate ownership of debug registers in protected mode after the
rework that landed in 6.14-rc1
- Stop pretending that we can run the protected mode without a GICv3
being present on the host
- Fix a use-after-free situation that can occur if a vcpu fails to
initialise the NV shadow S2 MMU contexts
- Always evaluate the need to arm a background timer for fully
emulated guest timers
- Fix the emulation of EL1 timers in the absence of FEAT_ECV
- Correctly handle the EL2 virtual timer, specially when HCR_EL2.E2H==0
s390:
- move some of the guest page table (gmap) logic into KVM itself,
inching towards the final goal of completely removing gmap from the
non-kvm memory management code.
As an initial set of cleanups, move some code from mm/gmap into kvm
and start using __kvm_faultin_pfn() to fault-in pages as needed;
but especially stop abusing page->index and page->lru to aid in the
pgdesc conversion.
x86:
- Add missing check in the fix to defer starting the huge page
recovery vhost_task
- SRSO_USER_KERNEL_NO does not need SYNTHESIZED_F"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (31 commits)
KVM: x86/mmu: Ensure NX huge page recovery thread is alive before waking
KVM: remove kvm_arch_post_init_vm
KVM: selftests: Fix spelling mistake "initally" -> "initially"
kvm: x86: SRSO_USER_KERNEL_NO is not synthesized
KVM: arm64: timer: Don't adjust the EL2 virtual timer offset
KVM: arm64: timer: Correctly handle EL1 timer emulation when !FEAT_ECV
KVM: arm64: timer: Always evaluate the need for a soft timer
KVM: arm64: Fix nested S2 MMU structures reallocation
KVM: arm64: Fail protected mode init if no vgic hardware is present
KVM: arm64: Flush/sync debug state in protected mode
KVM: s390: selftests: Streamline uc_skey test to issue iske after sske
KVM: s390: remove the last user of page->index
KVM: s390: move PGSTE softbits
KVM: s390: remove useless page->index usage
KVM: s390: move gmap_shadow_pgt_lookup() into kvm
KVM: s390: stop using lists to keep track of used dat tables
KVM: s390: stop using page->index for non-shadow gmaps
KVM: s390: move some gmap shadowing functions away from mm/gmap.c
KVM: s390: get rid of gmap_translate()
KVM: s390: get rid of gmap_fault()
...
Commit 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of
parents and children") exposed an issue related to simple_pm_bus_pm_ops
that uses pm_runtime_force_suspend() and pm_runtime_force_resume() as
bus type PM callbacks for the noirq phases of system-wide suspend and
resume.
The problem is that pm_runtime_force_suspend() does not distinguish
runtime-suspended devices from devices for which runtime PM has never
been enabled, so if it sees a device with runtime PM status set to
RPM_ACTIVE, it will assume that runtime PM is enabled for that device
and so it will attempt to suspend it with the help of its runtime PM
callbacks which may not be ready for that. As it turns out, this
causes simple_pm_bus_runtime_suspend() to crash due to a NULL pointer
dereference.
Another problem related to the above commit and simple_pm_bus_pm_ops is
that setting runtime PM status of a device handled by the latter to
RPM_ACTIVE will actually prevent it from being resumed because
pm_runtime_force_resume() only resumes devices with runtime PM status
set to RPM_SUSPENDED.
To mitigate these issues, do not allow power.set_active to propagate
beyond the parent of the device with DPM_FLAG_SMART_SUSPEND set that
will need to be resumed, which should be a sufficient stop-gap for the
time being, but they will need to be properly addressed in the future
because in general during system-wide resume it is necessary to resume
all devices in a dependency chain in which at least one device is going
to be resumed.
Fixes: 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of parents and children") Closes: https://lore.kernel.org/linux-pm/1c2433d4-7e0f-4395-b841-b8eac7c25651@nvidia.com/ Reported-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://patch.msgid.link/6137505.lOV4Wx5bFT@rjwysocki.net
Linus Torvalds [Sat, 8 Feb 2025 22:12:17 +0000 (14:12 -0800)]
Merge tag 'hardening-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening fixes from Kees Cook:
"Address a KUnit stack initialization regression that got tickled on
m68k, and solve a Clang(v14 and earlier) bug found by 0day:
- Fix stackinit KUnit regression on m68k
- Use ARRAY_SIZE() for memtostr*()/strtomem*()"
* tag 'hardening-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
string.h: Use ARRAY_SIZE() for memtostr*()/strtomem*()
compiler.h: Introduce __must_be_byte_array()
compiler.h: Move C string helpers into C-only kernel section
stackinit: Fix comment for test_small_end
stackinit: Keep selftest union size small on m68k
Linus Torvalds [Sat, 8 Feb 2025 22:04:21 +0000 (14:04 -0800)]
Merge tag 'seccomp-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp fix from Kees Cook:
"This is really a work-around for x86_64 having grown a syscall to
implement uretprobe, which has caused problems since v6.11.
This may change in the future, but for now, this fixes the unintended
seccomp filtering when uretprobe switched away from traps, and does so
with something that should be easy to backport.
- Allow uretprobe on x86_64 to avoid behavioral complications (Eyal
Birger)"
* tag 'seccomp-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests/seccomp: validate uretprobe syscall passes through seccomp
seccomp: passthrough uretprobe systemcall without filtering
Linus Torvalds [Sat, 8 Feb 2025 21:59:24 +0000 (13:59 -0800)]
Merge tag 'execve-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull execve fix from Kees Cook:
"This is an alpha-specific fix, but since it touched ELF I was asked to
carry it.
- alpha/elf: Fix misc/setarch test of util-linux by removing 32bit
support (Eric W. Biederman)"
* tag 'execve-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
alpha/elf: Fix misc/setarch test of util-linux by removing 32bit support
Linus Torvalds [Sat, 8 Feb 2025 21:45:34 +0000 (13:45 -0800)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"A number of fairly small fixes, mostly in drivers but two in the core
to change a retry for depopulation (a trendy new hdd thing that
reorganizes blocks away from failing elements) and one to fix a GFP_
annotation to avoid a lock dependency (the third core patch is all in
testing)"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: qla1280: Fix kernel oops when debug level > 2
scsi: ufs: core: Fix error return with query response
scsi: storvsc: Set correct data length for sending SCSI command without payload
scsi: ufs: core: Fix use-after free in init error and remove paths
scsi: core: Do not retry I/Os during depopulation
scsi: core: Use GFP_NOIO to avoid circular locking dependency
scsi: ufs: Fix toggling of clk_gating.state when clock gating is not allowed
scsi: ufs: core: Ensure clk_gating.lock is used only after initialization
scsi: ufs: core: Simplify temperature exception event handling
scsi: target: core: Add line break to status show
scsi: ufs: core: Fix the HIGH/LOW_TEMP Bit Definitions
scsi: core: Add passthrough tests for success and no failure definitions
Linus Torvalds [Sat, 8 Feb 2025 20:22:21 +0000 (12:22 -0800)]
Merge tag 'rust-fixes-6.14' of https://github.com/Rust-for-Linux/linux
Pull rust fixes from Miguel Ojeda:
- Do not export KASAN ODR symbols to avoid gendwarfksyms warnings
- Fix future Rust 1.86.0 (to be released 2025-04-03) x86_64 builds
- Clean future Rust 1.86.0 (to be released 2025-04-03) warning
- Fix future GCC 15 (to be released in a few months) builds
- Fix `rusttest` target in macOS
* tag 'rust-fixes-6.14' of https://github.com/Rust-for-Linux/linux:
x86: rust: set rustc-abi=x86-softfloat on rustc>=1.86.0
rust: kbuild: do not export generated KASAN ODR symbols
rust: kbuild: add -fzero-init-padding-bits to bindgen_skip_cflags
rust: init: use explicit ABI to clean warning in future compilers
rust: kbuild: use host dylib naming in rusttestlib-kernel
Linus Torvalds [Sat, 8 Feb 2025 20:18:02 +0000 (12:18 -0800)]
Merge tag 'ftrace-v6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace fix from Steven Rostedt:
"Function graph fix of notrace functions.
When the function graph tracer was restructured to use the global
section of the meta data in the shadow stack, the bit logic was
changed. There's a TRACE_GRAPH_NOTRACE_BIT that is the bit number in
the mask that tells if the function graph tracer is currently in the
"notrace" mode. The TRACE_GRAPH_NOTRACE is the mask with that bit set.
But when the code we restructured, the TRACE_GRAPH_NOTRACE_BIT was
used when it should have been the TRACE_GRAPH_NOTRACE mask. This made
notrace not work properly"
* tag 'ftrace-v6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
fgraph: Fix set_graph_notrace with setting TRACE_GRAPH_NOTRACE_BIT
Linus Torvalds [Sat, 8 Feb 2025 20:04:00 +0000 (12:04 -0800)]
Merge tag 'x86-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:
"Fix a build regression on GCC 15 builds, caused by GCC changing the
default C version that is overriden in the main Makefile but not in
the x86 boot code Makefile"
* tag 'x86-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Use '-std=gnu11' to fix build with GCC 15
Linus Torvalds [Sat, 8 Feb 2025 19:55:03 +0000 (11:55 -0800)]
Merge tag 'timers-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Ingo Molnar:
"Fix a PREEMPT_RT bug in the clocksource verification code that caused
false positive warnings.
Also fix a timer migration setup bug when new CPUs are added"
* tag 'timers-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers/migration: Fix off-by-one root mis-connection
clocksource: Use migrate_disable() to avoid calling get_random_u32() in atomic context
Linus Torvalds [Sat, 8 Feb 2025 19:16:22 +0000 (11:16 -0800)]
Merge tag 'sched-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Fix a cfs_rq->h_nr_runnable accounting bug that trips up a defensive
SCHED_WARN_ON() on certain workloads. The bug is believed to be
(accidentally) self-correcting, hence no behavioral side effects are
expected.
Also print se.slice in debug output, since this value can now be set
via the syscall ABI and can be useful to track"
* tag 'sched-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/debug: Provide slice length for fair tasks
sched/fair: Fix inaccurate h_nr_runnable accounting with delayed dequeue
Linus Torvalds [Sat, 8 Feb 2025 19:05:54 +0000 (11:05 -0800)]
Merge tag 'irq-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Ingo Molnar:
"Another followup fix for the procps genirq output formatting
regression caused by an optimization"
* tag 'irq-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Remove leading space from irq_chip::irq_print_chip() callbacks
Linus Torvalds [Sat, 8 Feb 2025 18:54:11 +0000 (10:54 -0800)]
Merge tag 'locking-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Ingo Molnar:
"Fix a dangling pointer bug in the futex code used by the uring code.
It isn't causing problems at the moment due to uring ABI limitations
leaving it essentially unused in current usages, but is a good idea to
fix nevertheless"
* tag 'locking-urgent-2025-02-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Pass in task to futex_queue()
Steven Rostedt [Sat, 8 Feb 2025 05:15:11 +0000 (00:15 -0500)]
fgraph: Fix set_graph_notrace with setting TRACE_GRAPH_NOTRACE_BIT
The code was restructured where the function graph notrace code, that
would not trace a function and all its children is done by setting a
NOTRACE flag when the function that is not to be traced is hit.
There's a TRACE_GRAPH_NOTRACE_BIT which defines the bit in the flags and a
TRACE_GRAPH_NOTRACE which is the mask with that bit set. But the
restructuring used TRACE_GRAPH_NOTRACE_BIT when it should have used
TRACE_GRAPH_NOTRACE.
-Wenum-enum-conversion was strengthened in clang-19 to warn for C, which
caused the kernel to move it to W=1 in commit 75b5ab134bb5 ("kbuild:
Move -Wenum-{compare-conditional,enum-conversion} into W=1") because
there were numerous instances that would break builds with -Werror.
Unfortunately, this is not a full solution, as more and more developers,
subsystems, and distributors are building with W=1 as well, so they
continue to see the numerous instances of this warning.
Since the move to W=1, there have not been many new instances that have
appeared through various build reports and the ones that have appeared
seem to be following similar existing patterns, suggesting that most
instances of this warning will not be real issues. The only alternatives
for silencing this warning are adding casts (which is generally seen as
an ugly practice) or refactoring the enums to macro defines or a unified
enum (which may be undesirable because of type safety in other parts of
the code).
Move the warning to W=2, where warnings that occur frequently but may be
relevant should reside.
Linus Torvalds [Sat, 8 Feb 2025 03:23:06 +0000 (19:23 -0800)]
Merge tag 'v6.14rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:
- Three DFS fixes: DFS mount fix, fix for noisy log msg and one to
remove some unused code
- SMB3 Lease fix
* tag 'v6.14rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: change lease epoch type from unsigned int to __u16
smb: client: get rid of kstrdup() in get_ses_refpath()
smb: client: fix noisy when tree connecting to DFS interlink targets
smb: client: don't trust DFSREF_STORAGE_SERVER bit
Linus Torvalds [Fri, 7 Feb 2025 20:21:54 +0000 (12:21 -0800)]
Merge tag 'drm-fixes-2025-02-08' of https://gitlab.freedesktop.org/drm/kernel
Pull drm fixes from Dave Airlie:
"Just regular drm fixes, amdgpu, xe and i915 mostly, but a few
scattered fixes. I think one of the i915 fixes fixes some build combos
that Guenter was seeing.
amdgpu:
- Add new tiling flag for DCC write compress disable
- Add BO metadata flag for DCC
- Fix potential out of bounds access in display
- Seamless boot fix
- CONFIG_FRAME_WARN fix
- PSR1 fix
xe:
- OA uAPI related fixes
- Fix SRIOV migration initialization
- Restore devcoredump to a sane state
i915:
- Fix the build error with clamp after WARN_ON on gcc 13.x+
- HDCP related fixes
- PMU fix zero delta busyness issue
- Fix page cleanup on DMA remap failure
- Drop 64bpp YUV formats from ICL+ SDR planes
- GuC log related fix
- DisplayPort related fixes
ivpu:
- Fix error handling
komeda:
- add return check
zynqmp:
- fix locking in DP code
ast:
- fix AST DP timeout
cec:
- fix broken CEC adapter check"
* tag 'drm-fixes-2025-02-08' of https://gitlab.freedesktop.org/drm/kernel: (29 commits)
drm/i915/dp: Fix potential infinite loop in 128b/132b SST
Revert "drm/amd/display: Use HW lock mgr for PSR1"
drm/amd/display: Respect user's CONFIG_FRAME_WARN more for dml files
accel/amdxdna: Add MODULE_FIRMWARE() declarations
drm/i915/dp: Iterate DSC BPP from high to low on all platforms
drm/xe: Fix and re-enable xe_print_blob_ascii85()
drm/xe/devcoredump: Move exec queue snapshot to Contexts section
drm/xe/oa: Set stream->pollin in xe_oa_buffer_check_unlocked
drm/xe/pf: Fix migration initialization
drm/xe/oa: Preserve oa_ctrl unused bits
drm/amd/display: Fix seamless boot sequence
drm/amd/display: Fix out-of-bound accesses
drm/amdgpu: add a BO metadata flag to disable write compression for Vulkan
drm/i915/backlight: Return immediately when scale() finds invalid parameters
drm/i915/dp: Return min bpc supported by source instead of 0
drm/i915/dp: fix the Adaptive sync Operation mode for SDP
drm/i915/guc: Debug print LRC state entries only if the context is pinned
drm/i915: Drop 64bpp YUV formats from ICL+ SDR planes
drm/i915: Fix page cleanup on DMA remap failure
drm/i915/pmu: Fix zero delta busyness issue
...
Linus Torvalds [Fri, 7 Feb 2025 19:00:33 +0000 (11:00 -0800)]
Merge tag 'block-6.14-20250207' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- MD pull request via Song:
- fix an error handling path for md-linear
- NVMe pull request via Keith:
- Connection fixes for fibre channel transport (Daniel)
- Endian fixes (Keith, Christoph)
- Cleanup fix for host memory buffer (Francis)
- Platform specific power quirks (Georg)
- Target memory leak (Sagi)
- Use appropriate controller state accessor (Daniel)
- Fixup for a regression introduced last week, where sunvdc wasn't
updated for an API change, causing compilation failures on sparc64.
* tag 'block-6.14-20250207' of git://git.kernel.dk/linux:
drivers/block/sunvdc.c: update the correct AIP call
md: Fix linear_set_limits()
nvme-fc: use ctrl state getter
nvme: make nvme_tls_attrs_group static
nvmet: add a missing endianess conversion in nvmet_execute_admin_connect
nvmet: the result field in nvmet_alloc_ctrl_args is little endian
nvmet: fix a memory leak in controller identify
nvme-fc: do not ignore connectivity loss during connecting
nvme: handle connectivity loss in nvme_set_queue_count
nvme-fc: go straight to connecting state when initializing
nvme-pci: Add TUXEDO IBP Gen9 to Samsung sleep quirk
nvme-pci: Add TUXEDO InfinityFlex to Samsung sleep quirk
nvme-pci: remove redundant dma frees in hmb
nvmet: fix rw control endian access
WangYuli [Fri, 7 Feb 2025 07:08:55 +0000 (15:08 +0800)]
kbuild: install-extmod-build: add missing quotation marks for CC variable
While attempting to build a Debian packages with CC="ccache gcc", I
saw the following error as builddeb builds linux-headers-$KERNELVERSION:
make HOSTCC=ccache gcc VPATH= srcroot=. -f ./scripts/Makefile.build obj=debian/linux-headers-6.14.0-rc1/usr/src/linux-headers-6.14.0-rc1/scripts
make[6]: *** No rule to make target 'gcc'. Stop.
Upon investigation, it seems that one instance of $(CC) variable reference
in ./scripts/package/install-extmod-build was missing quotation marks,
causing the above error.
Add the missing quotation marks around $(CC) to fix build.
Linus Torvalds [Fri, 7 Feb 2025 18:34:50 +0000 (10:34 -0800)]
Merge tag 'pm-6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix a handful of issues in the amd-pstate driver, the airoha
cpufreq driver build, a (recently added) possible NULL pointer
dereference in the cpufreq code and a possible memory leak in the
power capping subsystem:
- Fix cpufreq_policy reference counting and prevent max_perf from
going above the current limit in amd-pstate, and drop a redundant
goto label from it (Dhananjay Ugwekar)
- Prevent the per-policy boost_enabled flag in amd-pstate from
getting out of sync with the actual state after boot failures
(Lifeng Zheng)
- Fix a recently added possible NULL pointer dereference in the
cpufreq core (Aboorva Devarajan)
- Fix a build issue related to CONFIG_OF and COMPILE_TEST
dependencies in the airoha cpufreq driver (Arnd Bergmann)
- Fix a possible memory leak in the power capping subsystem (Joe
Hattori)"
* tag 'pm-6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq/amd-pstate: Fix cpufreq_policy ref counting
cpufreq: prevent NULL dereference in cpufreq_online()
cpufreq: airoha: modify CONFIG_OF dependency
cpufreq/amd-pstate: Fix max_perf updation with schedutil
cpufreq/amd-pstate: Remove the goto label in amd_pstate_update_limits
cpufreq/amd-pstate: Fix per-policy boost flag incorrect when fail
powercap: call put_device() on an error path in powercap_register_control_type()
Linus Torvalds [Fri, 7 Feb 2025 17:50:33 +0000 (09:50 -0800)]
Merge tag 'gpio-fixes-for-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fixes from Bartosz Golaszewski:
- fix interrupt support in gpio-pca953x
- fix configfs attribute locking in gpio-sim
- limit the visibility of the GPIO_GRGPIO Kconfig symbol to OF systems
only
- update MAINTAINERS
* tag 'gpio-fixes-for-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
MAINTAINERS: Use my kernel.org address for ACPI GPIO work
gpio: GPIO_GRGPIO should depend on OF
gpio: sim: lock hog configfs items if present
gpio: pca953x: Improve interrupt support
Linus Torvalds [Fri, 7 Feb 2025 17:22:31 +0000 (09:22 -0800)]
Merge tag 'vfs-6.14-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
- Fix fsnotify FMODE_NONOTIFY* handling.
This also disables fsnotify on all pseudo files by default apart from
very select exceptions. This carries a regression risk so we need to
watch out and adapt accordingly. However, it is overall a significant
improvement over the current status quo where every rando file can
get fsnotify enabled.
- Cleanup and simplify lockref_init() after recent lockref changes.
- Fix vboxfs build with gcc-15.
- Add an assert into inode_set_cached_link() to catch corrupt links.
- Allow users to also use an empty string check to detect whether a
given mount option string was empty or not.
- Fix how security options were appended to statmount()'s ->mnt_opt
field.
- Fix statmount() selftests to always check the returned mask.
- Fix uninitialized value in vfs_statx_path().
- Fix pidfs_ioctl() sanity checks to guard against ioctl() overloading
and preserve extensibility.
* tag 'vfs-6.14-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
vfs: sanity check the length passed to inode_set_cached_link()
pidfs: improve ioctl handling
fsnotify: disable pre-content and permission events by default
selftests: always check mask returned by statmount(2)
fsnotify: disable notification by default for all pseudo files
fs: fix adding security options to statmount.mnt_opt
fsnotify: use accessor to set FMODE_NONOTIFY_*
lockref: remove count argument of lockref_init
gfs2: switch to lockref_init(..., 1)
gfs2: use lockref_init for gl_lockref
statmount: let unset strings be empty
vboxsf: fix building with GCC 15
fs/stat.c: avoid harmless garbage value problem in vfs_statx_path()
Linus Torvalds [Fri, 7 Feb 2025 17:16:07 +0000 (09:16 -0800)]
Merge tag 'bcachefs-2025-02-06.2' of git://evilpiepirate.org/bcachefs
Pull bcachefs fixes from Kent Overstreet:
"Nothing major, things continue to be fairly quiet over here.
- add a SubmittingPatches to clarify that patches submitted for
bcachefs do, in fact, need to be tested
- discard path now correctly issues journal flushes when needed, this
fixes performance issues when the filesystem is nearly full and
we're bottlenecked on copygc
- fix a bug that could cause the pending rebalance work accounting to
be off when devices are being onlined/offlined; users should report
if they are still seeing this
- and a few more trivial ones"
* tag 'bcachefs-2025-02-06.2' of git://evilpiepirate.org/bcachefs:
bcachefs: bch2_bkey_sectors_need_rebalance() now only depends on bch_extent_rebalance
bcachefs: Fix rcu imbalance in bch2_fs_btree_key_cache_exit()
bcachefs: Fix discard path journal flushing
bcachefs: fix deadlock in journal_entry_open()
bcachefs: fix incorrect pointer check in __bch2_subvolume_delete()
bcachefs docs: SubmittingPatches.rst
Hector Martin [Thu, 6 Feb 2025 18:21:46 +0000 (03:21 +0900)]
MAINTAINERS: Remove myself
I no longer have any faith left in the kernel development process or
community management approach.
Apple/ARM platform development will continue downstream. If I feel like
sending some patches upstream in the future myself for whatever subtree
I may, or I may not. Anyone who feels like fighting the upstreaming
fight themselves is welcome to do so.
Signed-off-by: Hector Martin <marcan@marcan.st> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branches 'acpi-property' and 'acpi-resource'
Merge a new ACPI IRQ override quirk for Eluktronics MECH-17 (Gannon
Kolding) and an acpi_data_prop_read() fix making it reflect the OF
counterpart behavior in error cases (Andy Shevchenko).
* acpi-property:
ACPI: property: Fix return value for nval == 0 in acpi_data_prop_read()
* acpi-resource:
ACPI: resource: IRQ override for Eluktronics MECH-17
Mateusz Guzik [Tue, 4 Feb 2025 21:32:07 +0000 (22:32 +0100)]
vfs: sanity check the length passed to inode_set_cached_link()
This costs a strlen() call when instatianating a symlink.
Preferably it would be hidden behind VFS_WARN_ON (or compatible), but
there is no such facility at the moment. With the facility in place the
call can be patched out in production kernels.
In the meantime, since the cost is being paid unconditionally, use the
result to a fixup the bad caller.
This is not expected to persist in the long run (tm).
Sample splat:
bad length passed for symlink [/tmp/syz-imagegen43743633/file0/file0] (got 131109, expected 37)
[rest of WARN blurp goes here]
Pidfs supports extensible and non-extensible ioctls. The extensible
ioctls need to check for the ioctl number itself not just the ioctl
command otherwise both backward- and forward compatibility are broken.
The pidfs ioctl handler also needs to look at the type of the ioctl
command to guard against cases where "[...] a daemon receives some
random file descriptor from a (potentially less privileged) client and
expects the FD to be of some specific type, it might call ioctl() on
this FD with some type-specific command and expect the call to fail if
the FD is of the wrong type; but due to the missing type check, the
kernel instead performs some action that userspace didn't expect."
(cf. [1]]
Merge patch series "Fix for huge faults regression"
Amir Goldstein <amir73il@gmail.com> says:
The two Fix patches have been tested by Alex together and each one
independently.
I also verified that they pass the LTP inoityf/fanotify tests.
* patches from https://lore.kernel.org/r/20250203223205.861346-1-amir73il@gmail.com:
fsnotify: disable pre-content and permission events by default
fsnotify: disable notification by default for all pseudo files
fsnotify: use accessor to set FMODE_NONOTIFY_*
Amir Goldstein [Mon, 3 Feb 2025 22:32:05 +0000 (23:32 +0100)]
fsnotify: disable pre-content and permission events by default
After introducing pre-content events, we had a regression related to
disabling huge faults on files that should never have pre-content events
enabled.
This happened because the default f_mode of allocated files (0) does
not disable pre-content events.
Pre-content events are disabled in file_set_fsnotify_mode_by_watchers()
but internal files may not get to call this helper.
Initialize f_mode to disable permission and pre-content events for all
files and if needed they will be enabled for the callers of
file_set_fsnotify_mode_by_watchers().
Fixes: 20bf82a898b6 ("mm: don't allow huge faults for files with pre content watches") Reported-by: Alex Williamson <alex.williamson@redhat.com> Closes: https://lore.kernel.org/linux-fsdevel/20250131121703.1e4d00a7.alex.williamson@redhat.com/ Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20250203223205.861346-4-amir73il@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
Miklos Szeredi [Wed, 29 Jan 2025 16:06:41 +0000 (17:06 +0100)]
selftests: always check mask returned by statmount(2)
STATMOUNT_MNT_OPTS can actually be missing if there are no options. This
is a change of behavior since 75ead69a7173 ("fs: don't let statmount return
empty strings").
The other checks shouldn't actually trigger, but add them for correctness
and for easier debugging if the test fails.
Amir Goldstein [Mon, 3 Feb 2025 22:32:04 +0000 (23:32 +0100)]
fsnotify: disable notification by default for all pseudo files
Most pseudo files are not applicable for fsnotify events at all,
let alone to the new pre-content events.
Disable notifications to all files allocated with alloc_file_pseudo()
and enable legacy inotify events for the specific cases of pipe and
socket, which have known users of inotify events.
Pre-content events are also kept disabled for sockets and pipes.
Amir Goldstein [Mon, 3 Feb 2025 22:32:03 +0000 (23:32 +0100)]
fsnotify: use accessor to set FMODE_NONOTIFY_*
The FMODE_NONOTIFY_* bits are a 2-bits mode. Open coding manipulation
of those bits is risky. Use an accessor file_set_fsnotify_mode() to
set the mode.
Rename file_set_fsnotify_mode() => file_set_fsnotify_mode_from_watchers()
to make way for the simple accessor name.
Here's an updated version with an additional comment saying that
lockref_init() initializes count to 1.
* patches from https://lore.kernel.org/r/20250130135624.1899988-1-agruenba@redhat.com:
lockref: remove count argument of lockref_init
gfs2: switch to lockref_init(..., 1)
gfs2: use lockref_init for gl_lockref
In qd_alloc(), initialize the lockref count to 1 to cover the common
case. Compensate for that in gfs2_quota_init() by adjusting the count
back down to 0; this only occurs when mounting the filesystem rw.
Miklos Szeredi [Thu, 30 Jan 2025 12:15:00 +0000 (13:15 +0100)]
statmount: let unset strings be empty
Just like it's normal for unset values to be zero, unset strings should be
empty instead of containing random values.
It seems to be a typical mistake that the mask returned by statmount is not
checked, which can result in various bugs.
With this fix, these bugs are prevented, since it is highly likely that
userspace would just want to turn the missing mask case into an empty
string anyway (most of the recently found cases are of this type).
Brahmajit Das [Tue, 21 Jan 2025 16:26:48 +0000 (21:56 +0530)]
vboxsf: fix building with GCC 15
Building with GCC 15 results in build error
fs/vboxsf/super.c:24:54: error: initializer-string for array of ‘unsigned char’ is too long [-Werror=unterminated-string-initialization]
24 | static const unsigned char VBSF_MOUNT_SIGNATURE[4] = "\000\377\376\375";
| ^~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Due to GCC having enabled -Werror=unterminated-string-initialization[0]
by default. Separately initializing each array element of
VBSF_MOUNT_SIGNATURE to ensure NUL termination, thus satisfying GCC 15
and fixing the build error.
Su Hui [Sun, 19 Jan 2025 02:59:47 +0000 (10:59 +0800)]
fs/stat.c: avoid harmless garbage value problem in vfs_statx_path()
Clang static checker(scan-build) warning:
fs/stat.c:287:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
287 | stat->result_mask |= STATX_MNT_ID_UNIQUE;
| ~~~~~~~~~~~~~~~~~ ^
fs/stat.c:290:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
290 | stat->result_mask |= STATX_MNT_ID;
When vfs_getattr() failed because of security_inode_getattr(), 'stat' is
uninitialized. In this case, there is a harmless garbage problem in
vfs_statx_path(). It's better to return error directly when
vfs_getattr() failed, avoiding garbage value and more clearly.
Before attaching a new root to the old root, the children counter of the
new root is checked to verify that only the upcoming CPU's top group have
been connected to it. However since the recently added commit b729cc1ec21a
("timers/migration: Fix another race between hotplug and idle entry/exit")
this check is not valid anymore because the old root is pre-accounted
as a child to the new root. Therefore after connecting the upcoming
CPU's top group to the new root, the children count to be expected must
be 2 and not 1 anymore.
This omission results in the old root to not be connected to the new
root. Then eventually the system may run with more than one top level,
which defeats the purpose of a single idle migrator.
Also the old root is pre-accounted but not connected upon the new root
creation. But it can be connected to the new root later on. Therefore
the old root may be accounted twice to the new root. The propagation of
such overcommit can end up creating a double final top-level root with a
groupmask incorrectly initialized. Although harmless given that the final
top level roots will never have a parent to walk up to, this oddity
opportunistically reported the core issue:
genirq: Remove leading space from irq_chip::irq_print_chip() callbacks
The space separator was factored out from the multiple chip name prints,
but several irq_chip::irq_print_chip() callbacks still print a leading
space. Remove the superfluous double spaces.
projects / thirdparty / kernel / linux.git / log
