These structs are never modified.
To prevent malicious or accidental modifications due to bugs,
mark them as const.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'smp-urgent-2025-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull CPU hotplug fix from Ingo Molnar:
- Fix CPU hotplug callbacks to disable interrupts on UP kernels
* tag 'smp-urgent-2025-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu: Make atomic hotplug callbacks run with interrupts disabled on UP
individual changelogs for details.
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Merge tag 'mm-nonmm-stable-2025-12-11-11-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc updates from Andrew Morton:
"There are no significant series in this small merge. Please see the
individual changelogs for details"
[ Editor's note: it's mainly ocfs2 and a couple of random fixes ]
* tag 'mm-nonmm-stable-2025-12-11-11-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm: memfd_luo: add CONFIG_SHMEM dependency
mm: shmem: avoid build warning for CONFIG_SHMEM=n
ocfs2: fix memory leak in ocfs2_merge_rec_left()
ocfs2: invalidate inode if i_mode is zero after block read
ocfs2: avoid -Wflex-array-member-not-at-end warning
ocfs2: convert remaining read-only checks to ocfs2_emergency_state
ocfs2: add ocfs2_emergency_state helper and apply to setattr
checkpatch: add uninitialized pointer with __free attribute check
args: fix documentation to reflect the correct numbers
ocfs2: fix kernel BUG in ocfs2_find_victim_chain
liveupdate: luo_core: fix redundant bound check in luo_ioctl()
ocfs2: validate inline xattr size and entry count in ocfs2_xattr_ibody_list
fs/fat: remove unnecessary wrapper fat_max_cache()
ocfs2: replace deprecated strcpy with strscpy
ocfs2: check tl_used after reading it from trancate log inode
liveupdate: luo_file: don't use invalid list iterator
The new memfd code fails to link without SHMEM:
aarch64-linux-ld: mm/memfd_luo.o: in function `memfd_luo_retrieve_folios':
memfd_luo.c:(.text.memfd_luo_retrieve_folios+0xdc): undefined reference to `shmem_add_to_page_cache'
memfd_luo.c:(.text.memfd_luo_retrieve_folios+0x11c): undefined reference to `shmem_inode_acct_blocks'
memfd_luo.c:(.text.memfd_luo_retrieve_folios+0x134): undefined reference to `shmem_recalc_inode'
Add a Kconfig dependency to disallow that configuration.
Link: https://lkml.kernel.org/r/20251204100203.1034394-1-arnd@kernel.org
Fixes: b3749f174d ("mm: memfd_luo: allow preserving memfd")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The kernel test robot reported a Smatch warning:
kernel/liveupdate/luo_core.c:402 luo_ioctl() warn: unsigned 'nr' is
never less than zero.
This occurs because 'nr' is unsigned and LIVEUPDATE_CMD_BASE is currently
defined as 0, making the check (nr < LIVEUPDATE_CMD_BASE) always false.
Remove the explicit lower bound check. The logic remains correct because
'nr' is unsigned; if nr is less than LIVEUPDATE_CMD_BASE, the expression
(nr - LIVEUPDATE_CMD_BASE) will wrap around to a large positive value.
This will inevitably be larger than ARRAY_SIZE(luo_ioctl_ops) and be
caught by the upper bound check.
Link: https://lkml.kernel.org/r/20251130010919.1488230-1-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202511280300.6pvBmXUS-lkp@intel.com/
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If we exit a list_for_each_entry() without hitting a break then the list
iterator points to an offset from the list_head. It's a non-NULL but
invalid pointer and dereferencing it isn't allowed.
Introduce a new "found" variable to test instead.
Link: https://lkml.kernel.org/r/aSlMc4SS09Re4_xn@stanley.mountain
Fixes: 3ee1d673194e ("liveupdate: luo_file: implement file systems callbacks")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/r/202511280420.y9O4fyhX-lkp@intel.com/
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- Use the MSI parent domain API instead of the legacy API for setup and
teardown of PCI MSI IRQs
- Select POSIX_CPU_TIMERS_TASK_WORK now that VIRT_XFER_TO_GUEST_WORK has
been implemented for s390
- Fix a KVM bug which can lead to guest memory corruption
- Fix KASAN shadow memory mapping for hotplugged memory
- Minor bug fixes and improvements
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Merge tag 's390-6.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull more s390 updates from Heiko Carstens:
- Use the MSI parent domain API instead of the legacy API for setup and
teardown of PCI MSI IRQs
- Select POSIX_CPU_TIMERS_TASK_WORK now that VIRT_XFER_TO_GUEST_WORK
has been implemented for s390
- Fix a KVM bug which can lead to guest memory corruption
- Fix KASAN shadow memory mapping for hotplugged memory
- Minor bug fixes and improvements
* tag 's390-6.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/bug: Add missing alignment
s390/bug: Add missing CONFIG_BUG ifdef again
KVM: s390: Fix gmap_helper_zap_one_page() again
s390/pci: Migrate s390 IRQ logic to IRQ domain API
genirq: Change hwirq parameter to irq_hw_number_t
s390: Select POSIX_CPU_TIMERS_TASK_WORK
s390: Unmap early KASAN shadow on memory offlining
s390/vmem: Support 2G page splitting for KASAN shadow freeing
s390/boot: Use entire page for PTEs
s390/vmur: Use scnprintf() instead of sprintf()
- last minute fix for missing parenthesis in the recently merged code
(Hans de Goede) and removal of the excessive, non-fatal warnings (Dave
Kleikamp)
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Merge tag 'dma-mapping-6.19-2025-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux
Pull dma-mapping fixes from Marek Szyprowski:
- last minute fix for missing parenthesis in recently merged code (Hans
de Goede)
- removal of excessive, non-fatal warnings (Dave Kleikamp)
* tag 'dma-mapping-6.19-2025-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
dma-mapping: Fix DMA_BIT_MASK() macro being broken
dma/pool: eliminate alloc_pages warning in atomic_pool_expand
- Standardize on ktime_t in restart_block::time as well
(Thomas Weißschuh)
- Futex selftests:
- Add robust list testcases (André Almeida)
- Formatting fixes/cleanups (Carlos Llamas)
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-futex-2025-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex updates from Ingo Molnar:
- Standardize on ktime_t in restart_block::time as well (Thomas
Weißschuh)
- Futex selftests:
- Add robust list testcases (André Almeida)
- Formatting fixes/cleanups (Carlos Llamas)
* tag 'locking-futex-2025-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Store time as ktime_t in restart block
selftests/futex: Create test for robust list
selftests/futex: Skip tests if shmget unsupported
selftests/futex: Add newline to ksft_exit_fail_msg()
selftests/futex: Remove unused test_futex_mpol()
On SMP systems the CPU hotplug callbacks in the "starting" range are
invoked while the CPU is brought up and interrupts are still
disabled. Callbacks which are added later are invoked via the
hotplug-thread on the target CPU and interrupts are explicitly disabled.
In the UP case callbacks which are added later are invoked directly without
the thread indirection. This is in principle okay since there is just one
CPU but those callbacks are invoked with interrupt disabled code. That's
incorrect as those callbacks assume interrupt disabled context.
Disable interrupts before invoking the callbacks on UP if the state is
atomic and interrupts are expected to be disabled. The "save" part is
required because this is also invoked early in the boot process while
interrupts are disabled and must not be enabled prematurely.
Fixes: 06ddd17521 ("sched/smp: Always define is_percpu_thread() and scheduler_ipi()")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251127144723.ev9DuXXR@linutronix.de
setup_percpu_irq() was forgotten when the percpu_devid infrastructure was
updated to deal with CPU affinities.
In order to keep ignoring users of this legacy API, provide sensible
defaults by setting the affinity to cpu_online_mask if none was provided by
the caller.
Fixes: bdf4e2ac29 ("genirq: Allow per-cpu interrupt sharing for non-overlapping affinities")
Reported-by: Daniel Thompson <danielt@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251205091814.3944205-1-maz@kernel.org
Closes: https://lore.kernel.org/r/aTFozefMQRg7lYxh@aspen.lan
For events with inherit_stat enabled, a "read" event will be generated
to collect per task event counts on task exit.
The call chain is as follows:
do_exit
-> perf_event_exit_task
-> perf_event_exit_task_context
-> perf_event_exit_event
-> perf_remove_from_context
-> perf_child_detach
-> sync_child_event
-> perf_event_read_event
However, the child event context detaches the task too early in
perf_event_exit_task_context, which causes sync_child_event to never
generate the read event in this case, since child_event->ctx->task is
always set to TASK_TOMBSTONE. Fix that by moving context lock section
backward to ensure ctx->task is not set to TASK_TOMBSTONE before
generating the read event.
Because perf_event_free_task calls perf_event_exit_task_context with
exit = false to tear down all child events from the context, and the
task never lived, accessing the task PID can lead to a use-after-free.
To fix that, let sync_child_event read task from argument and move the
call to the only place it should be triggered to avoid the effect of
setting ctx->task to TASK_TOMESTONE, and add a task parameter to
perf_event_exit_event to trigger the sync_child_event properly when
needed.
This bug can be reproduced by running "perf record -s" and attaching to
any program that generates perf events in its child tasks. If we check
the result with "perf report -T", the last line of the report will leave
an empty table like "# PID TID", which is expected to contain the
per-task event counts by design.
Fixes: ef54c1a476 ("perf: Rework perf_event_exit_event()")
Signed-off-by: Thaumy Cheng <thaumy.love@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linux-perf-users@vger.kernel.org
Link: https://patch.msgid.link/20251209041600.963586-1-thaumy.love@gmail.com
atomic_pool_expand iteratively tries the allocation while decrementing
the page order. There is no need to issue a warning if an attempted
allocation fails.
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Fixes: d7e673ec2c ("dma-pool: Only allocate from CMA when in same memory zone")
[mszyprow: fixed typo]
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20251202152810.142370-1-dave.kleikamp@oracle.com
The irqdomain implementation internally represents hardware IRQs as
irq_hw_number_t, which is defined as unsigned long int. When providing
an irq_hw_number_t to the generic_handle_domain() functions that expect
and unsigned int hwirq, this can lead to a loss of information. Change
the hwirq parameter to irq_hw_number_t to support the full range of
hwirqs.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Tobias Schumacher <ts@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
- The 6 patch series "panic: sys_info: Refactor and fix a potential
issue" from Andy Shevchenko fixes a build issue and does some cleanup in
ib/sys_info.c.
- The 9 patch series "Implement mul_u64_u64_div_u64_roundup()" from
David Laight enhances the 64-bit math code on behalf of a PWM driver and
beefs up the test module for these library functions.
- The 2 patch series "scripts/gdb/symbols: make BPF debug info available
to GDB" from Ilya Leoshkevich makes BPF symbol names, sizes, and line
numbers available to the GDB debugger.
- The 4 patch series "Enable hung_task and lockup cases to dump system
info on demand" from Feng Tang adds a sysctl which can be used to cause
additional info dumping when the hung-task and lockup detectors fire.
- The 6 patch series "lib/base64: add generic encoder/decoder, migrate
users" from Kuan-Wei Chiu adds a general base64 encoder/decoder to lib/
and migrates several users away from their private implementations.
- The 2 patch series "rbree: inline rb_first() and rb_last()" from Eric
Dumazet makes TCP a little faster.
- The 9 patch series "liveupdate: Rework KHO for in-kernel users" from
Pasha Tatashin reworks the KEXEC Handover interfaces in preparation for
Live Update Orchestrator (LUO), and possibly for other future clients.
- The 13 patch series "kho: simplify state machine and enable dynamic
updates" from Pasha Tatashin increases the flexibility of KEXEC
Handover. Also preparation for LUO.
- The 18 patch series "Live Update Orchestrator" from Pasha Tatashin is
a major new feature targeted at cloud environments. Quoting the [0/N]:
This series introduces the Live Update Orchestrator, a kernel subsystem
designed to facilitate live kernel updates using a kexec-based reboot.
This capability is critical for cloud environments, allowing hypervisors
to be updated with minimal downtime for running virtual machines. LUO
achieves this by preserving the state of selected resources, such as
memory, devices and their dependencies, across the kernel transition.
As a key feature, this series includes support for preserving memfd file
descriptors, which allows critical in-memory data, such as guest RAM or
any other large memory region, to be maintained in RAM across the kexec
reboot.
Mike Rappaport merits a mention here, for his extensive review and
testing work.
- The 3 patch series "kexec: reorganize kexec and kdump sysfs" from
Sourabh Jain moves the kexec and kdump sysfs entries from /sys/kernel/
to /sys/kernel/kexec/ and adds back-compatibility symlinks which can
hopefully be removed one day.
- The 2 patch series "kho: fixes for vmalloc restoration" from Mike
Rapoport fixes a BUG which was being hit during KHO restoration of
vmalloc() regions.
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Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
- "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko)
fixes a build issue and does some cleanup in ib/sys_info.c
- "Implement mul_u64_u64_div_u64_roundup()" (David Laight)
enhances the 64-bit math code on behalf of a PWM driver and beefs up
the test module for these library functions
- "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich)
makes BPF symbol names, sizes, and line numbers available to the GDB
debugger
- "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang)
adds a sysctl which can be used to cause additional info dumping when
the hung-task and lockup detectors fire
- "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu)
adds a general base64 encoder/decoder to lib/ and migrates several
users away from their private implementations
- "rbree: inline rb_first() and rb_last()" (Eric Dumazet)
makes TCP a little faster
- "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin)
reworks the KEXEC Handover interfaces in preparation for Live Update
Orchestrator (LUO), and possibly for other future clients
- "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin)
increases the flexibility of KEXEC Handover. Also preparation for LUO
- "Live Update Orchestrator" (Pasha Tatashin)
is a major new feature targeted at cloud environments. Quoting the
cover letter:
This series introduces the Live Update Orchestrator, a kernel
subsystem designed to facilitate live kernel updates using a
kexec-based reboot. This capability is critical for cloud
environments, allowing hypervisors to be updated with minimal
downtime for running virtual machines. LUO achieves this by
preserving the state of selected resources, such as memory,
devices and their dependencies, across the kernel transition.
As a key feature, this series includes support for preserving
memfd file descriptors, which allows critical in-memory data, such
as guest RAM or any other large memory region, to be maintained in
RAM across the kexec reboot.
Mike Rappaport merits a mention here, for his extensive review and
testing work.
- "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain)
moves the kexec and kdump sysfs entries from /sys/kernel/ to
/sys/kernel/kexec/ and adds back-compatibility symlinks which can
hopefully be removed one day
- "kho: fixes for vmalloc restoration" (Mike Rapoport)
fixes a BUG which was being hit during KHO restoration of vmalloc()
regions
* tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits)
calibrate: update header inclusion
Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()"
vmcoreinfo: track and log recoverable hardware errors
kho: fix restoring of contiguous ranges of order-0 pages
kho: kho_restore_vmalloc: fix initialization of pages array
MAINTAINERS: TPM DEVICE DRIVER: update the W-tag
init: replace simple_strtoul with kstrtoul to improve lpj_setup
KHO: fix boot failure due to kmemleak access to non-PRESENT pages
Documentation/ABI: new kexec and kdump sysfs interface
Documentation/ABI: mark old kexec sysfs deprecated
kexec: move sysfs entries to /sys/kernel/kexec
test_kho: always print restore status
kho: free chunks using free_page() instead of kfree()
selftests/liveupdate: add kexec test for multiple and empty sessions
selftests/liveupdate: add simple kexec-based selftest for LUO
selftests/liveupdate: add userspace API selftests
docs: add documentation for memfd preservation via LUO
mm: memfd_luo: allow preserving memfd
liveupdate: luo_file: add private argument to store runtime state
mm: shmem: export some functions to internal.h
...
- Fix accounting of stop_count in file release
On opening the trace file, if "pause-on-trace" option is set, it will
increment the stop_count. On file release, it checks if stop_count is set,
and if so it decrements it. Since this code was originally written, the
stop_count can be incremented by other use cases. This makes just checking
the stop_count not enough to know if it should be decremented.
Add a new iterator flag called "PAUSE" and have it set if the open
disables tracing and only decrement the stop_count if that flag is set on
close.
- Remove length field in trace_seq_printf() of print_synth_event()
When printing the synthetic event that has a static length array field,
the vsprintf() of the trace_seq_printf() triggered a "(efault)" in the
output. That's because the print_fmt replaced the "%.*s" with "%s" causing
the arguments to be off.
- Fix a bunch of typos
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Merge tag 'trace-v6.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix accounting of stop_count in file release
On opening the trace file, if "pause-on-trace" option is set, it will
increment the stop_count. On file release, it checks if stop_count is
set, and if so it decrements it. Since this code was originally
written, the stop_count can be incremented by other use cases. This
makes just checking the stop_count not enough to know if it should be
decremented.
Add a new iterator flag called "PAUSE" and have it set if the open
disables tracing and only decrement the stop_count if that flag is
set on close.
- Remove length field in trace_seq_printf() of print_synth_event()
When printing the synthetic event that has a static length array
field, the vsprintf() of the trace_seq_printf() triggered a
"(efault)" in the output. That's because the print_fmt replaced the
"%.*s" with "%s" causing the arguments to be off.
- Fix a bunch of typos
* tag 'trace-v6.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Fix typo in trace_seq.c
tracing: Fix typo in trace_probe.c
tracing: Fix multiple typos in trace_osnoise.c
tracing: Fix multiple typos in trace_events_user.c
tracing: Fix typo in trace_events_trigger.c
tracing: Fix typo in trace_events_hist.c
tracing: Fix typo in trace_events_filter.c
tracing: Fix multiple typos in trace_events.c
tracing: Fix multiple typos in trace.c
tracing: Fix typo in ring_buffer_benchmark.c
tracing: Fix multiple typos in ring_buffer.c
tracing: Fix typo in fprobe.c
tracing: Fix typo in fpgraph.c
tracing: Fix fixed array of synthetic event
tracing: Fix enabling of tracing on file release
- Fix psi_dequeue() for Proxy Execution
- Fix hrtick() vs. scheduling context bug
- Fix unfairness caused by stalled tg_load_avg_contrib when the last task migrates out
- Fix whitespace noise in headers
- Remove a preempt-disable section in rt_mutex_setprio()
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Miscellaneous scheduler fixes/cleanups:
- Fix psi_dequeue() for Proxy Execution
- Fix hrtick() vs. scheduling context bug
- Fix unfairness caused by stalled tg_load_avg_contrib when the last
task migrates out
- Fix whitespace noise in headers
- Remove a preempt-disable section in rt_mutex_setprio()"
* tag 'sched-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Fix psi_dequeue() for Proxy Execution
sched/fair: Fix unfairness caused by stalled tg_load_avg_contrib when the last task migrates out
sched/rt: Remove a preempt-disable section in rt_mutex_setprio()
sched/hrtick: Fix hrtick() vs. scheduling context
sched/headers: Remove whitespace noise from kernel/sched/sched.h
allmodconfig builds, plus improve the quality of alternatives
instructions generated code and disassembly.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'objtool-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool fixes from Ingo Molnar:
"Address various objtool scalability bugs/inefficiencies exposed by
allmodconfig builds, plus improve the quality of alternatives
instructions generated code and disassembly"
* tag 'objtool-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
objtool: Simplify .annotate_insn code generation output some more
objtool: Add more robust signal error handling, detect and warn about stack overflows
objtool: Remove newlines and tabs from annotation macros
objtool: Consolidate annotation macros
x86/asm: Remove ANNOTATE_DATA_SPECIAL usage
x86/alternative: Remove ANNOTATE_DATA_SPECIAL usage
objtool: Fix stack overflow in validate_branch()
- next part of DMA mapping API refactoring to physical addresses as the primary
interface instead of page+offset parameters; this time dma_map_ops callbacks
are converted to physical addresses, what in turn results also in some
simplification of architecture specific code (Leon Romanovsky and Jason
Gunthorpe)
- clarify that dma_map_benchmark is not a kernel self-test, but standalone
tool (Qinxin Xia)
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Merge tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux
Pull dma-mapping updates from Marek Szyprowski:
- More DMA mapping API refactoring to physical addresses as the primary
interface instead of page+offset parameters.
This time dma_map_ops callbacks are converted to physical addresses,
what in turn results also in some simplification of architecture
specific code (Leon Romanovsky and Jason Gunthorpe)
- Clarify that dma_map_benchmark is not a kernel self-test, but
standalone tool (Qinxin Xia)
* tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
dma-mapping: remove unused map_page callback
xen: swiotlb: Convert mapping routine to rely on physical address
x86: Use physical address for DMA mapping
sparc: Use physical address DMA mapping
powerpc: Convert to physical address DMA mapping
parisc: Convert DMA map_page to map_phys interface
MIPS/jazzdma: Provide physical address directly
alpha: Convert mapping routine to rely on physical address
dma-mapping: remove unused mapping resource callbacks
xen: swiotlb: Switch to physical address mapping callbacks
ARM: dma-mapping: Switch to physical address mapping callbacks
ARM: dma-mapping: Reduce struct page exposure in arch_sync_dma*()
dma-mapping: convert dummy ops to physical address mapping
dma-mapping: prepare dma_map_ops to conversion to physical address
tools/dma: move dma_map_benchmark from selftests to tools/dma
Currently, if the sleep flag is set, psi_dequeue() doesn't
change any of the psi_flags.
This is because psi_task_switch() will clear TSK_ONCPU as well
as other potential flags (TSK_RUNNING), and the assumption is
that a voluntary sleep always consists of a task being dequeued
followed shortly there after with a psi_sched_switch() call.
Proxy Execution changes this expectation, as mutex-blocked tasks
that would normally sleep stay on the runqueue. But in the case
where the mutex-owning task goes to sleep, or the owner is on a
remote cpu, we will then deactivate the blocked task shortly
after.
In that situation, the mutex-blocked task will have had its
TSK_ONCPU cleared when it was switched off the cpu, but it will
stay TSK_RUNNING. Then if we later dequeue it (as currently done
if we hit a case find_proxy_task() can't yet handle, such as the
case of the owner being on another rq or a sleeping owner)
psi_dequeue() won't change any state (leaving it TSK_RUNNING),
as it incorrectly expects a psi_task_switch() call to
immediately follow.
Later on when the task get woken/re-enqueued, and psi_flags are
set for TSK_RUNNING, we hit an error as the task is already
TSK_RUNNING:
psi: inconsistent task state! task=188:kworker/28:0 cpu=28 psi_flags=4 clear=0 set=4
To resolve this, extend the logic in psi_dequeue() so that
if the sleep flag is set, we also check if psi_flags have
TSK_ONCPU set (meaning the psi_task_switch is imminent) before
we do the shortcut return.
If TSK_ONCPU is not set, that means we've already switched away,
and this psi_dequeue call needs to clear the flags.
Fixes: be41bde4c3 ("sched: Add an initial sketch of the find_proxy_task() function")
Reported-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: John Stultz <jstultz@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Tested-by: Haiyue Wang <haiyuewa@163.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://patch.msgid.link/20251205012721.756394-1-jstultz@google.com
Closes: https://lore.kernel.org/lkml/20251117185550.365156-1-kprateek.nayak@amd.com/
When a task is migrated out, there is a probability that the tg->load_avg
value will become abnormal. The reason is as follows:
1. Due to the 1ms update period limitation in update_tg_load_avg(), there
is a possibility that the reduced load_avg is not updated to tg->load_avg
when a task migrates out.
2. Even though __update_blocked_fair() traverses the leaf_cfs_rq_list and
calls update_tg_load_avg() for cfs_rqs that are not fully decayed, the key
function cfs_rq_is_decayed() does not check whether
cfs->tg_load_avg_contrib is null. Consequently, in some cases,
__update_blocked_fair() removes cfs_rqs whose avg.load_avg has not been
updated to tg->load_avg.
Add a check of cfs_rq->tg_load_avg_contrib in cfs_rq_is_decayed(),
which fixes the case (2.) mentioned above.
Fixes: 1528c661c2 ("sched/fair: Ratelimit update to tg->load_avg")
Signed-off-by: xupengbo <xupengbo@oppo.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Aaron Lu <ziqianlu@bytedance.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Aaron Lu <ziqianlu@bytedance.com>
Link: https://patch.msgid.link/20250827022208.14487-1-xupengbo@oppo.com
rt_mutex_setprio() has only one caller: rt_mutex_adjust_prio(). It
expects that task_struct::pi_lock and rt_mutex_base::wait_lock are held.
Both locks are raw_spinlock_t and are acquired with disabled interrupts.
Nevertheless rt_mutex_setprio() disables preemption while invoking
__balance_callbacks() and raw_spin_rq_unlock(). Even if one of the
balance callbacks unlocks the rq then it must not enable interrupts
because rt_mutex_base::wait_lock is still locked.
Therefore interrupts should remain disabled and disabling preemption is
not needed.
Commit 4c9a4bc89a ("sched: Allow balance callbacks for check_class_changed()")
adds a preempt-disable section to rt_mutex_setprio() and
__sched_setscheduler(). In __sched_setscheduler() the preemption is
disabled before rq is unlocked and interrupts enabled but I don't see
why it makes a difference in rt_mutex_setprio().
Remove the preempt_disable() section from rt_mutex_setprio().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20251127155529.t_sTatE4@linutronix.de
The sched_class::task_tick() method is called on the donor
sched_class, and sched_tick() hands it rq->donor as argument,
which is consistent.
However, while hrtick() uses the donor sched_class, it then passes
rq->curr, which is inconsistent. Fix it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <jstultz@google.com>
Link: https://patch.msgid.link/20250918080205.442967033@infradead.org
This is the first half of the driver changes:
- A treewide interface change to the "syscore" operations for
power management, as a preparation for future Tegra specific
changes.
- Reset controller updates with added drivers for LAN969x, eic770
and RZ/G3S SoCs.
- Protection of system controller registers on Renesas and Google SoCs,
to prevent trivially triggering a system crash from e.g. debugfs
access.
- soc_device identification updates on Nvidia, Exynos and Mediatek
- debugfs support in the ST STM32 firewall driver
- Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI
- Cleanups for memory controller support on Nvidia and Renesas
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Merge tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull SoC driver updates from Arnd Bergmann:
"This is the first half of the driver changes:
- A treewide interface change to the "syscore" operations for power
management, as a preparation for future Tegra specific changes
- Reset controller updates with added drivers for LAN969x, eic770 and
RZ/G3S SoCs
- Protection of system controller registers on Renesas and Google
SoCs, to prevent trivially triggering a system crash from e.g.
debugfs access
- soc_device identification updates on Nvidia, Exynos and Mediatek
- debugfs support in the ST STM32 firewall driver
- Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI
- Cleanups for memory controller support on Nvidia and Renesas"
* tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits)
memory: tegra186-emc: Fix missing put_bpmp
Documentation: reset: Remove reset_controller_add_lookup()
reset: fix BIT macro reference
reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe
reset: th1520: Support reset controllers in more subsystems
reset: th1520: Prepare for supporting multiple controllers
dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys
dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets
reset: remove legacy reset lookup code
clk: davinci: psc: drop unused reset lookup
reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC
reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY
dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support
reset: eswin: Add eic7700 reset driver
dt-bindings: reset: eswin: Documentation for eic7700 SoC
reset: sparx5: add LAN969x support
dt-bindings: reset: microchip: Add LAN969x support
soc: rockchip: grf: Add select correct PWM implementation on RK3368
soc/tegra: pmc: Add USB wake events for Tegra234
amba: tegra-ahb: Fix device leak on SMMU enable
...
dentries of created objects in dcache (and undo it when removing those).
Reference is grabbed and not released, but it's not actually _stored_
anywhere. That works, but it's hard to follow and verify; among other
things, we have no way to tell _which_ of the increments is intended
to be an unpaired one. Worse, on removal we need to decide whether
the reference had already been dropped, which can be non-trivial if
that removal is on umount and we need to figure out if this dentry is
pinned due to e.g. unlink() not done. Usually that is handled by using
kill_litter_super() as ->kill_sb(), but there are open-coded special
cases of the same (consider e.g. /proc/self).
Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT)
marking those "leaked" dentries. Having it set claims responsibility
for +1 in refcount.
The end result this series is aiming for:
* get these unbalanced dget() and dput() replaced with new primitives that
would, in addition to adjusting refcount, set and clear persistency flag.
* instead of having kill_litter_super() mess with removing the remaining
"leaked" references (e.g. for all tmpfs files that hadn't been removed
prior to umount), have the regular shrink_dcache_for_umount() strip
DCACHE_PERSISTENT of all dentries, dropping the corresponding
reference if it had been set. After that kill_litter_super() becomes
an equivalent of kill_anon_super().
Doing that in a single step is not feasible - it would affect too many places
in too many filesystems. It has to be split into a series.
This work has really started early in 2024; quite a few preliminary pieces
have already gone into mainline. This chunk is finally getting to the
meat of that stuff - infrastructure and most of the conversions to it.
Some pieces are still sitting in the local branches, but the bulk of
that stuff is here.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull persistent dentry infrastructure and conversion from Al Viro:
"Some filesystems use a kinda-sorta controlled dentry refcount leak to
pin dentries of created objects in dcache (and undo it when removing
those). A reference is grabbed and not released, but it's not actually
_stored_ anywhere.
That works, but it's hard to follow and verify; among other things, we
have no way to tell _which_ of the increments is intended to be an
unpaired one. Worse, on removal we need to decide whether the
reference had already been dropped, which can be non-trivial if that
removal is on umount and we need to figure out if this dentry is
pinned due to e.g. unlink() not done. Usually that is handled by using
kill_litter_super() as ->kill_sb(), but there are open-coded special
cases of the same (consider e.g. /proc/self).
Things get simpler if we introduce a new dentry flag
(DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set
claims responsibility for +1 in refcount.
The end result this series is aiming for:
- get these unbalanced dget() and dput() replaced with new primitives
that would, in addition to adjusting refcount, set and clear
persistency flag.
- instead of having kill_litter_super() mess with removing the
remaining "leaked" references (e.g. for all tmpfs files that hadn't
been removed prior to umount), have the regular
shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries,
dropping the corresponding reference if it had been set. After that
kill_litter_super() becomes an equivalent of kill_anon_super().
Doing that in a single step is not feasible - it would affect too many
places in too many filesystems. It has to be split into a series.
This work has really started early in 2024; quite a few preliminary
pieces have already gone into mainline. This chunk is finally getting
to the meat of that stuff - infrastructure and most of the conversions
to it.
Some pieces are still sitting in the local branches, but the bulk of
that stuff is here"
* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
d_make_discardable(): warn if given a non-persistent dentry
kill securityfs_recursive_remove()
convert securityfs
get rid of kill_litter_super()
convert rust_binderfs
convert nfsctl
convert rpc_pipefs
convert hypfs
hypfs: swich hypfs_create_u64() to returning int
hypfs: switch hypfs_create_str() to returning int
hypfs: don't pin dentries twice
convert gadgetfs
gadgetfs: switch to simple_remove_by_name()
convert functionfs
functionfs: switch to simple_remove_by_name()
functionfs: fix the open/removal races
functionfs: need to cancel ->reset_work in ->kill_sb()
functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
functionfs: don't abuse ffs_data_closed() on fs shutdown
convert selinuxfs
...
- The 10 patch series "__vmalloc()/kvmalloc() and no-block support" from
Uladzislau Rezki reworks the vmalloc() code to support non-blocking
allocations (GFP_ATOIC, GFP_NOWAIT).
- The 2 patch series "ksm: fix exec/fork inheritance" from xu xin fixes
a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited
across fork/exec.
- The 4 patch series "mm/zswap: misc cleanup of code and documentations"
from SeongJae Park does some light maintenance work on the zswap code.
- The 5 patch series "mm/page_owner: add debugfs files 'show_handles'
and 'show_stacks_handles'" from Mauricio Faria de Oliveira enhances the
/sys/kernel/debug/page_owner debug feature. It adds unique identifiers
to differentiate the various stack traces so that userspace monitoring
tools can better match stack traces over time.
- The 2 patch series "mm/page_alloc: pcp->batch cleanups" from Joshua
Hahn makes some minor alterations to the page allocator's per-cpu-pages
feature.
- The 2 patch series "Improve UFFDIO_MOVE scalability by removing
anon_vma lock" from Lokesh Gidra addresses a scalability issue in
userfaultfd's UFFDIO_MOVE operation.
- The 2 patch series "kasan: cleanups for kasan_enabled() checks" from
Sabyrzhan Tasbolatov performs some cleanup in the KASAN code.
- The 2 patch series "drivers/base/node: fold node register and
unregister functions" from Donet Tom cleans up the NUMA node handling
code a little.
- The 4 patch series "mm: some optimizations for prot numa" from Kefeng
Wang provides some cleanups and small optimizations to the NUMA
allocation hinting code.
- The 5 patch series "mm/page_alloc: Batch callers of
free_pcppages_bulk" from Joshua Hahn addresses long lock hold times at
boot on large machines. These were causing (harmless) softlockup
warnings.
- The 2 patch series "optimize the logic for handling dirty file folios
during reclaim" from Baolin Wang removes some now-unnecessary work from
page reclaim.
- The 10 patch series "mm/damon: allow DAMOS auto-tuned for per-memcg
per-node memory usage" from SeongJae Park enhances the DAMOS auto-tuning
feature.
- The 2 patch series "mm/damon: fixes for address alignment issues in
DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan fixes DAMON_LRU_SORT
and DAMON_RECLAIM with certain userspace configuration.
- The 15 patch series "expand mmap_prepare functionality, port more
users" from Lorenzo Stoakes enhances the new(ish)
file_operations.mmap_prepare() method and ports additional callsites
from the old ->mmap() over to ->mmap_prepare().
- The 8 patch series "Fix stale IOTLB entries for kernel address space"
from Lu Baolu fixes a bug (and possible security issue on non-x86) in
the IOMMU code. In some situations the IOMMU could be left hanging onto
a stale kernel pagetable entry.
- The 4 patch series "mm/huge_memory: cleanup __split_unmapped_folio()"
from Wei Yang cleans up and optimizes the folio splitting code.
- The 5 patch series "mm, swap: misc cleanup and bugfix" from Kairui
Song implements some cleanups and a minor fix in the swap discard code.
- The 8 patch series "mm/damon: misc documentation fixups" from SeongJae
Park does as advertised.
- The 9 patch series "mm/damon: support pin-point targets removal" from
SeongJae Park permits userspace to remove a specific monitoring target
in the middle of the current targets list.
- The 2 patch series "mm: MISC follow-up patches for linux/pgalloc.h"
from Harry Yoo implements a couple of cleanups related to mm header file
inclusion.
- The 2 patch series "mm/swapfile.c: select swap devices of default
priority round robin" from Baoquan He improves the selection of swap
devices for NUMA machines.
- The 3 patch series "mm: Convert memory block states (MEM_*) macros to
enums" from Israel Batista changes the memory block labels from macros
to enums so they will appear in kernel debug info.
- The 3 patch series "ksm: perform a range-walk to jump over holes in
break_ksm" from Pedro Demarchi Gomes addresses an inefficiency when KSM
unmerges an address range.
- The 22 patch series "mm/damon/tests: fix memory bugs in kunit tests"
from SeongJae Park fixes leaks and unhandled malloc() failures in DAMON
userspace unit tests.
- The 2 patch series "some cleanups for pageout()" from Baolin Wang
cleans up a couple of minor things in the page scanner's
writeback-for-eviction code.
- The 2 patch series "mm/hugetlb: refactor sysfs/sysctl interfaces" from
Hui Zhu moves hugetlb's sysfs/sysctl handling code into a new file.
- The 9 patch series "introduce VM_MAYBE_GUARD and make it sticky" from
Lorenzo Stoakes makes the VMA guard regions available in /proc/pid/smaps
and improves the mergeability of guarded VMAs.
- The 2 patch series "mm: perform guard region install/remove under VMA
lock" from Lorenzo Stoakes reduces mmap lock contention for callers
performing VMA guard region operations.
- The 2 patch series "vma_start_write_killable" from Matthew Wilcox
starts work in permitting applications to be killed when they are
waiting on a read_lock on the VMA lock.
- The 11 patch series "mm/damon/tests: add more tests for online
parameters commit" from SeongJae Park adds additional userspace testing
of DAMON's "commit" feature.
- The 9 patch series "mm/damon: misc cleanups" from SeongJae Park does
that.
- The 2 patch series "make VM_SOFTDIRTY a sticky VMA flag" from Lorenzo
Stoakes addresses the possible loss of a VMA's VM_SOFTDIRTY flag when
that VMA is merged with another.
- The 16 patch series "mm: support device-private THP" from Balbir Singh
introduces support for Transparent Huge Page (THP) migration in zone
device-private memory.
- The 3 patch series "Optimize folio split in memory failure" from Zi
Yan optimizes folio split operations in the memory failure code.
- The 2 patch series "mm/huge_memory: Define split_type and consolidate
split support checks" from Wei Yang provides some more cleanups in the
folio splitting code.
- The 16 patch series "mm: remove is_swap_[pte, pmd]() + non-swap
entries, introduce leaf entries" from Lorenzo Stoakes cleans up our
handling of pagetable leaf entries by introducing the concept of
'software leaf entries', of type softleaf_t.
- The 4 patch series "reparent the THP split queue" from Muchun Song
reparents the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory resources.
- The 3 patch series "unify PMD scan results and remove redundant
cleanup" from Wei Yang does a little cleanup in the hugepage collapse
code.
- The 6 patch series "zram: introduce writeback bio batching" from
Sergey Senozhatsky improves zram writeback efficiency by introducing
batched bio writeback support.
- The 4 patch series "memcg: cleanup the memcg stats interfaces" from
Shakeel Butt cleans up our handling of the interrupt safety of some
memcg stats.
- The 4 patch series "make vmalloc gfp flags usage more apparent" from
Vishal Moola cleans up vmalloc's handling of incoming GFP flags.
- The 6 patch series "mm: Add soft-dirty and uffd-wp support for RISC-V"
from Chunyan Zhang teches soft dirty and userfaultfd write protect
tracking to use RISC-V's Svrsw60t59b extension.
- The 5 patch series "mm: swap: small fixes and comment cleanups" from
Youngjun Park fixes a small bug and cleans up some of the swap code.
- The 4 patch series "initial work on making VMA flags a bitmap" from
Lorenzo Stoakes starts work on converting the vma struct's flags to a
bitmap, so we stop running out of them, especially on 32-bit.
- The 2 patch series "mm/swapfile: fix and cleanup swap list iterations"
from Youngjun Park addresses a possible bug in the swap discard code and
cleans things up a little.
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Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
Rework the vmalloc() code to support non-blocking allocations
(GFP_ATOIC, GFP_NOWAIT)
"ksm: fix exec/fork inheritance" (xu xin)
Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
inherited across fork/exec
"mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
Some light maintenance work on the zswap code
"mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
Enhance the /sys/kernel/debug/page_owner debug feature by adding
unique identifiers to differentiate the various stack traces so
that userspace monitoring tools can better match stack traces over
time
"mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
Minor alterations to the page allocator's per-cpu-pages feature
"Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
Address a scalability issue in userfaultfd's UFFDIO_MOVE operation
"kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)
"drivers/base/node: fold node register and unregister functions" (Donet Tom)
Clean up the NUMA node handling code a little
"mm: some optimizations for prot numa" (Kefeng Wang)
Cleanups and small optimizations to the NUMA allocation hinting
code
"mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
Address long lock hold times at boot on large machines. These were
causing (harmless) softlockup warnings
"optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
Remove some now-unnecessary work from page reclaim
"mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
Enhance the DAMOS auto-tuning feature
"mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
configuration
"expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
Enhance the new(ish) file_operations.mmap_prepare() method and port
additional callsites from the old ->mmap() over to ->mmap_prepare()
"Fix stale IOTLB entries for kernel address space" (Lu Baolu)
Fix a bug (and possible security issue on non-x86) in the IOMMU
code. In some situations the IOMMU could be left hanging onto a
stale kernel pagetable entry
"mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
Clean up and optimize the folio splitting code
"mm, swap: misc cleanup and bugfix" (Kairui Song)
Some cleanups and a minor fix in the swap discard code
"mm/damon: misc documentation fixups" (SeongJae Park)
"mm/damon: support pin-point targets removal" (SeongJae Park)
Permit userspace to remove a specific monitoring target in the
middle of the current targets list
"mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
A couple of cleanups related to mm header file inclusion
"mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
improve the selection of swap devices for NUMA machines
"mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
Change the memory block labels from macros to enums so they will
appear in kernel debug info
"ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
Address an inefficiency when KSM unmerges an address range
"mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
Fix leaks and unhandled malloc() failures in DAMON userspace unit
tests
"some cleanups for pageout()" (Baolin Wang)
Clean up a couple of minor things in the page scanner's
writeback-for-eviction code
"mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
Move hugetlb's sysfs/sysctl handling code into a new file
"introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
Make the VMA guard regions available in /proc/pid/smaps and
improves the mergeability of guarded VMAs
"mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
Reduce mmap lock contention for callers performing VMA guard region
operations
"vma_start_write_killable" (Matthew Wilcox)
Start work on permitting applications to be killed when they are
waiting on a read_lock on the VMA lock
"mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
Add additional userspace testing of DAMON's "commit" feature
"mm/damon: misc cleanups" (SeongJae Park)
"make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
VMA is merged with another
"mm: support device-private THP" (Balbir Singh)
Introduce support for Transparent Huge Page (THP) migration in zone
device-private memory
"Optimize folio split in memory failure" (Zi Yan)
"mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
Some more cleanups in the folio splitting code
"mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
Clean up our handling of pagetable leaf entries by introducing the
concept of 'software leaf entries', of type softleaf_t
"reparent the THP split queue" (Muchun Song)
Reparent the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory
resources
"unify PMD scan results and remove redundant cleanup" (Wei Yang)
A little cleanup in the hugepage collapse code
"zram: introduce writeback bio batching" (Sergey Senozhatsky)
Improve zram writeback efficiency by introducing batched bio
writeback support
"memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
Clean up our handling of the interrupt safety of some memcg stats
"make vmalloc gfp flags usage more apparent" (Vishal Moola)
Clean up vmalloc's handling of incoming GFP flags
"mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
Teach soft dirty and userfaultfd write protect tracking to use
RISC-V's Svrsw60t59b extension
"mm: swap: small fixes and comment cleanups" (Youngjun Park)
Fix a small bug and clean up some of the swap code
"initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
Start work on converting the vma struct's flags to a bitmap, so we
stop running out of them, especially on 32-bit
"mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
Address a possible bug in the swap discard code and clean things
up a little
[ This merge also reverts commit ebb9aeb980 ("vfio/nvgrace-gpu:
register device memory for poison handling") because it looks
broken to me, I've asked for clarification - Linus ]
* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
mm: fix vma_start_write_killable() signal handling
mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
mm/swapfile: fix list iteration when next node is removed during discard
fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
mm/kfence: add reboot notifier to disable KFENCE on shutdown
memcg: remove inc/dec_lruvec_kmem_state helpers
selftests/mm/uffd: initialize char variable to Null
mm: fix DEBUG_RODATA_TEST indentation in Kconfig
mm: introduce VMA flags bitmap type
tools/testing/vma: eliminate dependency on vma->__vm_flags
mm: simplify and rename mm flags function for clarity
mm: declare VMA flags by bit
zram: fix a spelling mistake
mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
pagemap: update BUDDY flag documentation
mm: swap: remove scan_swap_map_slots() references from comments
mm: swap: change swap_alloc_slow() to void
mm, swap: remove redundant comment for read_swap_cache_async
mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
...
The commit 4d38328eb4 ("tracing: Fix synth event printk format for str
fields") replaced "%.*s" with "%s" but missed removing the number size of
the dynamic and static strings. The commit e1a453a57b ("tracing: Do not
add length to print format in synthetic events") fixed the dynamic part
but did not fix the static part. That is, with the commands:
# echo 's:wake_lat char[] wakee; u64 delta;' >> /sys/kernel/tracing/dynamic_events
# echo 'hist:keys=pid:ts=common_timestamp.usecs if !(common_flags & 0x18)' > /sys/kernel/tracing/events/sched/sched_waking/trigger
# echo 'hist:keys=next_pid:delta=common_timestamp.usecs-$ts:onmatch(sched.sched_waking).trace(wake_lat,next_comm,$delta)' > /sys/kernel/tracing/events/sched/sched_switch/trigger
That caused the output of:
<idle>-0 [001] d..5. 193.428167: wake_lat: wakee=(efault)sshd-sessiondelta=155
sshd-session-879 [001] d..5. 193.811080: wake_lat: wakee=(efault)kworker/u34:5delta=58
<idle>-0 [002] d..5. 193.811198: wake_lat: wakee=(efault)bashdelta=91
The commit e1a453a57b fixed the part where the synthetic event had
"char[] wakee". But if one were to replace that with a static size string:
# echo 's:wake_lat char[16] wakee; u64 delta;' >> /sys/kernel/tracing/dynamic_events
Where "wakee" is defined as "char[16]" and not "char[]" making it a static
size, the code triggered the "(efaul)" again.
Remove the added STR_VAR_LEN_MAX size as the string is still going to be
nul terminated.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Douglas Raillard <douglas.raillard@arm.com>
Link: https://patch.msgid.link/20251204151935.5fa30355@gandalf.local.home
Fixes: e1a453a57b ("tracing: Do not add length to print format in synthetic events")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The trace file will pause tracing if the tracing instance has the
"pause-on-trace" option is set. This happens when the file is opened, and
it is unpaused when the file is closed. When this was first added, there
was only one user that paused tracing. On open, the check to pause was:
if (!iter->snapshot && (tr->trace_flags & TRACE_ITER(PAUSE_ON_TRACE)))
Where if it is not the snapshot tracer and the "pause-on-trace" option is
set, then it increments a "stop_count" of the trace instance.
On close, the check is:
if (!iter->snapshot && tr->stop_count)
That is, if it is not the snapshot buffer and it was stopped, it will
re-enable tracing.
Now there's more places that stop tracing. This means, if something else
stops tracing the tr->stop_count will be non-zero, and that means if the
trace file is closed, it will decrement the stop_count even though it
never incremented it. This causes a warning because when the user that
stopped tracing enables it again, the stop_count goes below zero.
Instead of relying on the stop_count being set to know if the close of
the trace file should enable tracing again, add a new flag to the trace
iterator. The trace iterator is unique per open of the trace file, and if
the open stops tracing set the trace iterator PAUSE flag. On close, if the
PAUSE flag is set, then re-enable it again.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251202161751.24abaaf1@gandalf.local.home
Fixes: 06e0a548ba ("tracing: Do not disable tracing when reading the trace file")
Reported-by: syzbot+ccdec3bfe0beec58a38d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/692f44a5.a70a0220.2ea503.00c8.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* Move jiffies converters out of kernel/sysctl.c
Moved the jiffies converters into kernel/time/jiffies.c and replaced
the pipe-max-size proc_handler converter with a macro based version.
This is all part of the effort to relocate non-sysctl logic out of
kernel/sysctl.c into more relevant subsystems. No functional changes.
* Generalize proc handler converter creation
Removed duplicated sysctl converter logic by consolidating it in
macros. These are used inside sysctl core as well as in pipe.c and
jiffies.c. Converter kernel and user space pointer args are now
automatically const qualified for the convenience of the caller. No
functional changes.
* Miscellaneous
Fixed kernel-doc format warnings, removed unnecessary __user
qualifiers, and moved the nmi_watchdog sysctl into .rodata.
* Testing
This series was run through sysctl selftests/kunit test suite in
x86_64. It went into linux-next after rc2, giving it a good 4/5 weeks
of testing.
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Merge tag 'sysctl-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl
Pull sysctl updates from Joel Granados:
- Move jiffies converters out of kernel/sysctl.c
Move the jiffies converters into kernel/time/jiffies.c and replace
the pipe-max-size proc_handler converter with a macro based version.
This is all part of the effort to relocate non-sysctl logic out of
kernel/sysctl.c into more relevant subsystems. No functional changes.
- Generalize proc handler converter creation
Remove duplicated sysctl converter logic by consolidating it in
macros. These are used inside sysctl core as well as in pipe.c and
jiffies.c. Converter kernel and user space pointer args are now
automatically const qualified for the convenience of the caller. No
functional changes.
- Miscellaneous
Fix kernel-doc format warnings, remove unnecessary __user
qualifiers, and move the nmi_watchdog sysctl into .rodata.
- Testing
This series was run through sysctl selftests/kunit test suite in
x86_64. It went into linux-next after rc2, giving it a good 4/5 weeks
of testing.
* tag 'sysctl-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: (21 commits)
sysctl: Wrap do_proc_douintvec with the public function proc_douintvec_conv
sysctl: Create pipe-max-size converter using sysctl UINT macros
sysctl: Move proc_doulongvec_ms_jiffies_minmax to kernel/time/jiffies.c
sysctl: Move jiffies converters to kernel/time/jiffies.c
sysctl: Move UINT converter macros to sysctl header
sysctl: Move INT converter macros to sysctl header
sysctl: Allow custom converters from outside sysctl
sysctl: remove __user qualifier from stack_erasing_sysctl buffer argument
sysctl: Create macro for user-to-kernel uint converter
sysctl: Add optional range checking to SYSCTL_UINT_CONV_CUSTOM
sysctl: Create unsigned int converter using new macro
sysctl: Add optional range checking to SYSCTL_INT_CONV_CUSTOM
sysctl: Create integer converters with one macro
sysctl: Create converter functions with two new macros
sysctl: Discriminate between kernel and user converter params
sysctl: Indicate the direction of operation with macro names
sysctl: Remove superfluous __do_proc_* indirection
sysctl: Remove superfluous tbl_data param from "dovec" functions
sysctl: Replace void pointer with const pointer to ctl_table
sysctl: fix kernel-doc format warning
...
- fprobe: Performance enhancement of the fprobe using rhltable
. fprobe: use rhltable for fprobe_ip_table. The fprobe IP table has
been converted to use an rhltable for improved performance when
dealing with a large number of probed functions.
. Fix a suspicious RCU usage warning of the above change in the
fprobe entry handler.
. Remove an unused local variable of the above change.
. Fix to initialize fprobe_ip_table in core_initcall().
- fprobe: Performance optimization of fprobe by ftrace
. fprobe: Use ftrace instead of fgraph for entry only probes. This
avoids the unneeded overhead of fgraph stack setup.
. Also update fprobe selftest for entry-only probe.
. fprobe: Use ftrace only if CONFIG_DYNAMIC_FTRACE_WITH_ARGS or
WITH_REGS is defined.
- probes: Cleanup probe event subsystems.
. uprobe/eprobe: Allocate traceprobe_parse_context per probe instead
of each probe argument parsing. This reduce memory allocation/free
of temporary working memory.
. uprobes: Cleanup code using __free().
. eprobes: Cleanup code using __free().
. probes: Cleanup code using __free(trace_probe_log_clear) to clear
error log automatically.
. probes: Replace strcpy() with memcpy() in __trace_probe_log_err().
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Merge tag 'probes-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes updates from Masami Hiramatsu:
"fprobe performance enhancement using rhltable:
- use rhltable for fprobe_ip_table. The fprobe IP table has been
converted to use an rhltable for improved performance when dealing
with a large number of probed functions
- Fix a suspicious RCU usage warning of the above change in the
fprobe entry handler
- Remove an unused local variable of the above change
- Fix to initialize fprobe_ip_table in core_initcall()
Performance optimization of fprobe by ftrace:
- Use ftrace instead of fgraph for entry only probes. This avoids the
unneeded overhead of fgraph stack setup
- Also update fprobe selftest for entry-only probe
- fprobe: Use ftrace only if CONFIG_DYNAMIC_FTRACE_WITH_ARGS or
WITH_REGS is defined
Cleanup probe event subsystems:
- Allocate traceprobe_parse_context per probe instead of each probe
argument parsing. This reduce memory allocation/free of temporary
working memory
- Cleanup code using __free()
- Replace strcpy() with memcpy() in __trace_probe_log_err()"
* tag 'probes-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: fprobe: use ftrace if CONFIG_DYNAMIC_FTRACE_WITH_ARGS
lib/test_fprobe: add testcase for mixed fprobe
tracing: fprobe: optimization for entry only case
tracing: fprobe: Fix to init fprobe_ip_table earlier
tracing: fprobe: Remove unused local variable
tracing: probes: Replace strcpy() with memcpy() in __trace_probe_log_err()
tracing: fprobe: fix suspicious rcu usage in fprobe_entry
tracing: uprobe: eprobes: Allocate traceprobe_parse_context per probe
tracing: uprobes: Cleanup __trace_uprobe_create() with __free()
tracing: eprobe: Cleanup eprobe event using __free()
tracing: probes: Use __free() for trace_probe_log
tracing: fprobe: use rhltable for fprobe_ip_table
The allocation of the per CPU buffer descriptor, the buffer page
descriptors and the buffer page data itself can be pretty ugly.
Add some helper macros and a function to have the code that allocates
buffer pages and such look a little cleaner.
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Merge tag 'trace-ringbuffer-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull trace ring-buffer cleanup from Steven Rostedt:
- Add helper functions for allocations
The allocation of the per CPU buffer descriptor, the buffer page
descriptors and the buffer page data itself can be pretty ugly.
Add some helper macros and a function to have the code that allocates
buffer pages and such look a little cleaner.
* tag 'trace-ringbuffer-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Add helper functions for allocations
- Adapt the ftracetest script to be run from a different folder
This uses the already existing OPT_TEST_DIR but extends it further to run
independent tests, then add an --rv flag to allow using the script for
testing RV (mostly) independently on ftrace.
- Add basic RV selftests in selftests/verification for more validations
Add more validations for available/enabled monitors and reactors. This
could have caught the bug introducing kernel panic solved above. Tests use
ftracetest.
- Convert react() function in reactor to use va_list directly
Use a central helper to handle the variadic arguments. Clean up macros
and mark functions as static.
- Add lockdep annotations to reactors to have lockdep complain of errors
If the reactors are called from improper context. Useful to develop new
reactors. This highlights a warning in the panic reactor that is related
to the printk subsystem and not to RV.
- Convert core RV code to use lock guards and __free helpers
This completely removes goto statements.
- Fix compilation if !CONFIG_RV_REACTORS
Fix the warning by keeping LTL monitor variable as always static.
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Merge tag 'trace-rv-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull runtime verifier updates from Steven Rostedt:
- Adapt the ftracetest script to be run from a different folder
This uses the already existing OPT_TEST_DIR but extends it further to
run independent tests, then add an --rv flag to allow using the
script for testing RV (mostly) independently on ftrace.
- Add basic RV selftests in selftests/verification for more validations
Add more validations for available/enabled monitors and reactors.
This could have caught the bug introducing kernel panic solved above.
Tests use ftracetest.
- Convert react() function in reactor to use va_list directly
Use a central helper to handle the variadic arguments. Clean up
macros and mark functions as static.
- Add lockdep annotations to reactors to have lockdep complain of
errors
If the reactors are called from improper context. Useful to develop
new reactors. This highlights a warning in the panic reactor that is
related to the printk subsystem and not to RV.
- Convert core RV code to use lock guards and __free helpers
This completely removes goto statements.
- Fix compilation if !CONFIG_RV_REACTORS
Fix the warning by keeping LTL monitor variable as always static.
* tag 'trace-rv-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
rv: Fix compilation if !CONFIG_RV_REACTORS
rv: Convert to use __free
rv: Convert to use lock guard
rv: Add explicit lockdep context for reactors
rv: Make rv_reacting_on() static
rv: Pass va_list to reactors
selftests/verification: Add initial RV tests
selftest/ftrace: Generalise ftracetest to use with RV
- Fix regression of pid filtering of function graph tracer
When the function graph tracer allowed multiple instances of
graph tracing using subops, the filtering by pid broke.
The ftrace_ops->private that was used for pid filtering wasn't
updated on creation.
The wrong function entry callback was used when pid filtering was
enabled when the function graph tracer started, which meant that
the pid filtering wasn't happening.
- Remove no longer needed ftrace_trace_task()
With PID filtering working via ftrace_pids_enabled() and fgraph_pid_func(),
the coarse-grained ftrace_trace_task() check in graph_entry() is obsolete.
It was only a fallback for uninitialized op->private (now fixed), and its
removal ensures consistent PID filtering with standard function tracing.
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Merge tag 'ftrace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace updates from Steven Rostedt:
- Fix regression of pid filtering of function graph tracer
When the function graph tracer allowed multiple instances of graph
tracing using subops, the filtering by pid broke.
The ftrace_ops->private that was used for pid filtering wasn't
updated on creation.
The wrong function entry callback was used when pid filtering was
enabled when the function graph tracer started, which meant that
the pid filtering wasn't happening.
- Remove no longer needed ftrace_trace_task()
With PID filtering working via ftrace_pids_enabled() and
fgraph_pid_func(), the coarse-grained ftrace_trace_task()
check in graph_entry() is obsolete.
It was only a fallback for uninitialized op->private (now fixed),
and its removal ensures consistent PID filtering with standard
function tracing.
* tag 'ftrace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
fgraph: Remove coarse PID filtering from graph_entry()
fgraph: Check ftrace_pids_enabled on registration for early filtering
fgraph: Initialize ftrace_ops->private for function graph ops
- Merge branch shared with kprobes on extending trace options
The trace options were defined by a 32 bit variable. This limits the
tracing instances to have a total of 32 different options. As that limit
has been hit, and more options are being added, increase the option mask
to a 64 bit number, doubling the number of options available.
As this is required for the kprobe topic branches as well as the tracing
topic branch, a separate branch was created and merged into both.
- Make trace_user_fault_read() available for the rest of tracing
The function trace_user_fault_read() is used by trace_marker file read to
allow reading user space to be done fast and without locking or
allocations. Make this available so that the system call trace events can
use it too.
- Have system call trace events read user space values
Now that the system call trace events callbacks are called in a faultable
context, take advantage of this and read the user space buffers for
various system calls. For example, show the path name of the openat system
call instead of just showing the pointer to that path name in user space.
Also show the contents of the buffer of the write system call. Several
system call trace events are updated to make tracing into a light weight
strace tool for all applications in the system.
- Update perf system call tracing to do the same
- And a config and syscall_user_buf_size file to control the size of the buffer
Limit the amount of data that can be read from user space. The default
size is 63 bytes but that can be expanded to 165 bytes.
- Allow the persistent ring buffer to print system calls normally
The persistent ring buffer prints trace events by their type and ignores
the print_fmt. This is because the print_fmt may change from kernel to
kernel. As the system call output is fixed by the system call ABI itself,
there's no reason to limit that. This makes reading the system call events
in the persistent ring buffer much nicer and easier to understand.
- Add options to show text offset to function profiler
The function profiler that counts the number of times a function is hit
currently lists all functions by its name and offset. But this becomes
ambiguous when there are several functions with the same name. Add a
tracing option that changes the output to be that of _text+offset
instead. Now a user space tool can use this information to map the
_text+offset to the unique function it is counting.
- Report bad dynamic event command
If a bad command is passed to the dynamic_events file, report it properly
in the error log.
- Clean up tracer options
Clean up the tracer option code a bit, by removing some useless code and
also using switch statements instead of a series of if statements.
- Have tracing options be instance specific
Tracers can have their own options (function tracer, irqsoff tracer,
function graph tracer, etc). But now that the same tracer can be enabled
in multiple trace instances, their options are still global. The API is
per instance, thus changing one affects other instances. This isn't even
consistent, as the option take affect differently depending on when an
tracer started in an instance. Make the options for instances only affect
the instance it is changed under.
- Optimize pid_list lock contention
Whenever the pid_list is read, it uses a spin lock. This happens at every
sched switch. Taking the lock at sched switch can be removed by instead
using a seqlock counter.
- Clean up the trace trigger structures
The trigger code uses two different structures to implement a single
tigger. This was due to trying to reuse code for the two different types
of triggers (always on trigger, and count limited trigger). But by adding
a single field to one structure, the other structure could be absorbed
into the first structure making he code easier to understand.
- Create a bulk garbage collector for trace triggers
If user space has triggers for several hundreds of events and then removes
them, it can take several seconds to complete. This is because each
removal calls the slow tracepoint_synchronize_unregister() that can take
hundreds of milliseconds to complete. Instead, create a helper thread that
will do the clean up. When a trigger is removed, it will create the
kthread if it isn't already created, and then add the trigger to a llist.
The kthread will take the items off the llist, call
tracepoint_synchronize_unregister(), and then remove the items it took
off. It will then check if there's more items to free before sleeping.
This makes user space removing all these triggers to finish in less than a
second.
- Allow function tracing of some of the tracing infrastructure code
Because the tracing code can cause recursion issues if it is traced by the
function tracer the entire tracing directory disables function tracing.
But not all of tracing causes issues if it is traced. Namely, the event
tracing code. Add a config that enables some of the tracing code to be
traced to help in debugging it. Note, when this is enabled, it does add
noise to general function tracing, especially if events are enabled as
well (which is a common case).
- Add boot-time backup instance for persistent buffer
The persistent ring buffer is used mostly for kernel crash analysis in the
field. One issue is that if there's a crash, the data in the persistent
ring buffer must be read before tracing can begin using it. This slows
down the boot process. Once tracing starts in the persistent ring buffer,
the old data must be freed and the addresses no longer match and old
events can't be in the buffer with new events.
Create a way to create a backup buffer that copies the persistent ring
buffer at boot up. Then after a crash, the always on tracer can begin
immediately as well as the normal boot process while the crash analysis
tooling uses the backup buffer. After the backup buffer is finished being
read, it can be removed.
- Enable function graph args and return address options at the same time
Currently the when reading of arguments in the function graph tracer is
enabled, the option to record the parent function in the entry event can
not be enabled. Update the code so that it can.
- Add new struct_offset() helper macro
Add a new macro that takes a pointer to a structure and a name of one of
its members and it will return the offset of that member. This allows the
ring buffer code to simplify the following:
From: size = struct_size(entry, buf, cnt - sizeof(entry->id));
To: size = struct_offset(entry, id) + cnt;
There should be other simplifications that this macro can help out with as
well.
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Merge tag 'trace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing updates from Steven Rostedt:
- Extend tracing option mask to 64 bits
The trace options were defined by a 32 bit variable. This limits the
tracing instances to have a total of 32 different options. As that
limit has been hit, and more options are being added, increase the
option mask to a 64 bit number, doubling the number of options
available.
As this is required for the kprobe topic branches as well as the
tracing topic branch, a separate branch was created and merged into
both.
- Make trace_user_fault_read() available for the rest of tracing
The function trace_user_fault_read() is used by trace_marker file
read to allow reading user space to be done fast and without locking
or allocations. Make this available so that the system call trace
events can use it too.
- Have system call trace events read user space values
Now that the system call trace events callbacks are called in a
faultable context, take advantage of this and read the user space
buffers for various system calls. For example, show the path name of
the openat system call instead of just showing the pointer to that
path name in user space. Also show the contents of the buffer of the
write system call. Several system call trace events are updated to
make tracing into a light weight strace tool for all applications in
the system.
- Update perf system call tracing to do the same
- And a config and syscall_user_buf_size file to control the size of
the buffer
Limit the amount of data that can be read from user space. The
default size is 63 bytes but that can be expanded to 165 bytes.
- Allow the persistent ring buffer to print system calls normally
The persistent ring buffer prints trace events by their type and
ignores the print_fmt. This is because the print_fmt may change from
kernel to kernel. As the system call output is fixed by the system
call ABI itself, there's no reason to limit that. This makes reading
the system call events in the persistent ring buffer much nicer and
easier to understand.
- Add options to show text offset to function profiler
The function profiler that counts the number of times a function is
hit currently lists all functions by its name and offset. But this
becomes ambiguous when there are several functions with the same
name.
Add a tracing option that changes the output to be that of
'_text+offset' instead. Now a user space tool can use this
information to map the '_text+offset' to the unique function it is
counting.
- Report bad dynamic event command
If a bad command is passed to the dynamic_events file, report it
properly in the error log.
- Clean up tracer options
Clean up the tracer option code a bit, by removing some useless code
and also using switch statements instead of a series of if
statements.
- Have tracing options be instance specific
Tracers can have their own options (function tracer, irqsoff tracer,
function graph tracer, etc). But now that the same tracer can be
enabled in multiple trace instances, their options are still global.
The API is per instance, thus changing one affects other instances.
This isn't even consistent, as the option take affect differently
depending on when an tracer started in an instance. Make the options
for instances only affect the instance it is changed under.
- Optimize pid_list lock contention
Whenever the pid_list is read, it uses a spin lock. This happens at
every sched switch. Taking the lock at sched switch can be removed by
instead using a seqlock counter.
- Clean up the trace trigger structures
The trigger code uses two different structures to implement a single
tigger. This was due to trying to reuse code for the two different
types of triggers (always on trigger, and count limited trigger). But
by adding a single field to one structure, the other structure could
be absorbed into the first structure making he code easier to
understand.
- Create a bulk garbage collector for trace triggers
If user space has triggers for several hundreds of events and then
removes them, it can take several seconds to complete. This is
because each removal calls tracepoint_synchronize_unregister() that
can take hundreds of milliseconds to complete.
Instead, create a helper thread that will do the clean up. When a
trigger is removed, it will create the kthread if it isn't already
created, and then add the trigger to a llist. The kthread will take
the items off the llist, call tracepoint_synchronize_unregister(),
and then remove the items it took off. It will then check if there's
more items to free before sleeping.
This makes user space removing all these triggers to finish in less
than a second.
- Allow function tracing of some of the tracing infrastructure code
Because the tracing code can cause recursion issues if it is traced
by the function tracer the entire tracing directory disables function
tracing. But not all of tracing causes issues if it is traced.
Namely, the event tracing code. Add a config that enables some of the
tracing code to be traced to help in debugging it. Note, when this is
enabled, it does add noise to general function tracing, especially if
events are enabled as well (which is a common case).
- Add boot-time backup instance for persistent buffer
The persistent ring buffer is used mostly for kernel crash analysis
in the field. One issue is that if there's a crash, the data in the
persistent ring buffer must be read before tracing can begin using
it. This slows down the boot process. Once tracing starts in the
persistent ring buffer, the old data must be freed and the addresses
no longer match and old events can't be in the buffer with new
events.
Create a way to create a backup buffer that copies the persistent
ring buffer at boot up. Then after a crash, the always on tracer can
begin immediately as well as the normal boot process while the crash
analysis tooling uses the backup buffer. After the backup buffer is
finished being read, it can be removed.
- Enable function graph args and return address options at the same
time
Currently the when reading of arguments in the function graph tracer
is enabled, the option to record the parent function in the entry
event can not be enabled. Update the code so that it can.
- Add new struct_offset() helper macro
Add a new macro that takes a pointer to a structure and a name of one
of its members and it will return the offset of that member. This
allows the ring buffer code to simplify the following:
From: size = struct_size(entry, buf, cnt - sizeof(entry->id));
To: size = struct_offset(entry, id) + cnt;
There should be other simplifications that this macro can help out
with as well
* tag 'trace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (42 commits)
overflow: Introduce struct_offset() to get offset of member
function_graph: Enable funcgraph-args and funcgraph-retaddr to work simultaneously
tracing: Add boot-time backup of persistent ring buffer
ftrace: Allow tracing of some of the tracing code
tracing: Use strim() in trigger_process_regex() instead of skip_spaces()
tracing: Add bulk garbage collection of freeing event_trigger_data
tracing: Remove unneeded event_mutex lock in event_trigger_regex_release()
tracing: Merge struct event_trigger_ops into struct event_command
tracing: Remove get_trigger_ops() and add count_func() from trigger ops
tracing: Show the tracer options in boot-time created instance
ftrace: Avoid redundant initialization in register_ftrace_direct
tracing: Remove unused variable in tracing_trace_options_show()
fgraph: Make fgraph_no_sleep_time signed
tracing: Convert function graph set_flags() to use a switch() statement
tracing: Have function graph tracer option sleep-time be per instance
tracing: Move graph-time out of function graph options
tracing: Have function graph tracer option funcgraph-irqs be per instance
trace/pid_list: optimize pid_list->lock contention
tracing: Have function graph tracer define options per instance
tracing: Have function tracer define options per instance
...
Thomas Weißschuh