Pull MSI updates from Thomas Gleixner:
"Updates for the MSI subsystem (core code and PCI):
- Switch the MSI descriptor locking to lock guards
- Replace a broken and naive implementation of PCI/MSI-X control word
updates in the PCI/TPH driver with a properly serialized variant in
the PCI/MSI core code.
- Remove the MSI descriptor abuse in the SCCI/UFS/QCOM driver by
replacing the direct access to the MSI descriptors with the proper
API function calls. People will never understand that APIs exist
for a reason...
- Provide core infrastructre for the upcoming PCI endpoint library
extensions. Currently limited to ARM GICv3+, but in theory
extensible to other architectures.
- Provide a MSI domain::teardown() callback, which allows drivers to
undo the effects of the prepare() callback.
- Move the MSI domain::prepare() callback invocation to domain
creation time to avoid redundant (and in case of ARM/GIC-V3-ITS
confusing) invocations on every allocation.
In combination with the new teardown callback this removes some
ugly hacks in the GIC-V3-ITS driver, which pretended to work around
the short comings of the core code so far. With this update the
code is correct by design and implementation.
- Make the irqchip MSI library globally available, provide a MSI
parent domain creation helper and convert a bunch of (PCI/)MSI
drivers over to the modern MSI parent mechanism. This is the first
step to get rid of at least one incarnation of the three PCI/MSI
management schemes.
- The usual small cleanups and improvements"
* tag 'irq-msi-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
PCI/MSI: Use bool for MSI enable state tracking
PCI: tegra: Convert to MSI parent infrastructure
PCI: xgene: Convert to MSI parent infrastructure
PCI: apple: Convert to MSI parent infrastructure
irqchip/msi-lib: Honour the MSI_FLAG_NO_AFFINITY flag
irqchip/mvebu: Convert to msi_create_parent_irq_domain() helper
irqchip/gic: Convert to msi_create_parent_irq_domain() helper
genirq/msi: Add helper for creating MSI-parent irq domains
irqchip: Make irq-msi-lib.h globally available
irqchip/gic-v3-its: Use allocation size from the prepare call
genirq/msi: Engage the .msi_teardown() callback on domain removal
genirq/msi: Move prepare() call to per-device allocation
irqchip/gic-v3-its: Implement .msi_teardown() callback
genirq/msi: Add .msi_teardown() callback as the reverse of .msi_prepare()
irqchip/gic-v3-its: Add support for device tree msi-map and msi-mask
dt-bindings: PCI: pci-ep: Add support for iommu-map and msi-map
irqchip/gic-v3-its: Set IRQ_DOMAIN_FLAG_MSI_IMMUTABLE for ITS
irqdomain: Add IRQ_DOMAIN_FLAG_MSI_IMMUTABLE and irq_domain_is_msi_immutable()
platform-msi: Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()
genirq/msi: Rename msi_[un]lock_descs()
...
Pull irq cleanups from Thomas Gleixner:
"A set of cleanups for the generic interrupt subsystem:
- Consolidate on one set of functions for the interrupt domain code
to get rid of pointlessly duplicated code with only marginal
different semantics.
- Update the documentation accordingly and consolidate the coding
style of the irqdomain header"
* tag 'irq-cleanups-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
irqdomain: Consolidate coding style
irqdomain: Fix kernel-doc and add it to Documentation
Documentation: irqdomain: Update it
Documentation: irq-domain.rst: Simple improvements
Documentation: irq/concepts: Minor improvements
Documentation: irq/concepts: Add commas and reflow
irqdomain: Improve kernel-docs of functions
irqdomain: Make struct irq_domain_info variables const
irqdomain: Use irq_domain_instantiate()'s return value as initializers
irqdomain: Drop irq_linear_revmap()
pinctrl: keembay: Switch to irq_find_mapping()
irqchip/armada-370-xp: Switch to irq_find_mapping()
gpu: ipu-v3: Switch to irq_find_mapping()
gpio: idt3243x: Switch to irq_find_mapping()
sh: Switch to irq_find_mapping()
powerpc: Switch to irq_find_mapping()
irqdomain: Drop irq_domain_add_*() functions
powerpc: Switch irq_domain_add_nomap() to use fwnode
thermal: Switch to irq_domain_create_linear()
soc: Switch to irq_domain_create_*()
...
Pull irq controller updates from Thomas Gleixner:
"Update for interrupt chip drivers:
- Convert the generic interrupt chip to lock guards to remove copy &
pasta boilerplate code and gotos.
- A new driver fot the interrupt controller in the EcoNet EN751221
MIPS SoC.
- Extend the SG2042-MSI driver to support the new SG2044 SoC
- Updates and cleanups for the (ancient) VT8500 driver
- Improve the scalability of the ARM GICV4.1 ITS driver by utilizing
node local copies a VM's interrupt translation table when possible.
This results in a 12% reduction of VM IPI latency in certain
workloads.
- The usual cleanups and improvements all over the place"
* tag 'irq-drivers-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
irqchip/irq-pruss-intc: Simplify chained interrupt handler setup
irqchip/gic-v4.1: Use local 4_1 ITS to generate VSGI
irqchip/econet-en751221: Switch to of_fwnode_handle()
irqchip/irq-vt8500: Switch to irq_domain_create_*()
irqchip/econet-en751221: Switch to irq_domain_create_linear()
irqchip/irq-vt8500: Use fewer global variables and add error handling
irqchip/irq-vt8500: Use a dedicated chained handler function
irqchip/irq-vt8500: Don't require 8 interrupts from a chained controller
irqchip/irq-vt8500: Drop redundant copy of the device node pointer
irqchip/irq-vt8500: Split up ack/mask functions
irqchip/sg2042-msi: Fix wrong type cast in sg2044_msi_irq_ack()
irqchip/sg2042-msi: Add the Sophgo SG2044 MSI interrupt controller
irqchip/sg2042-msi: Introduce configurable chipinfo for SG2042
irqchip/sg2042-msi: Rename functions and data structures to be SG2042 agnostic
dt-bindings: interrupt-controller: Add Sophgo SG2044 MSI controller
genirq/generic-chip: Fix incorrect lock guard conversions
genirq/generic-chip: Remove unused lock wrappers
irqchip: Convert generic irqchip locking to guards
gpio: mvebu: Convert generic irqchip locking to guard()
ARM: orion/gpio:: Convert generic irqchip locking to guard()
...
Pull irq core updates from Thomas Gleixner:
"Updates for the generic interrupt subsystem core code:
- Address a long standing subtle problem in the CPU hotplug code for
affinity-managed interrupts.
Affinity-managed interrupts are shut down by the core code when the
last CPU in the affinity set goes offline and started up again when
the first CPU in the affinity set becomes online again.
This unfortunately does not take into account whether an interrupt
has been disabled before the last CPU goes offline and starts up
the interrupt unconditionally when the first CPU becomes online
again.
That's obviously not what drivers expect.
Address this by preserving the disabled state for affinity-managed
interrupts accross these CPU hotplug operations. All non-managed
interrupts are not affected by this because startup/shutdown is
coupled to request/free_irq() which obviously has to reset state.
- Support three-cell scheme interrupts to allow GPIO drivers to
specify interrupts from an already existing scheme
- Switch the interrupt subsystem core to lock guards. This gets rid
of quite some copy & pasta boilerplate code all over the place.
- The usual small cleanups and improvements all over the place"
* tag 'irq-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits)
genirq/irqdesc: Remove double locking in hwirq_show()
genirq: Retain disable depth for managed interrupts across CPU hotplug
genirq: Bump the size of the local variable for sprintf()
genirq/manage: Use the correct lock guard in irq_set_irq_wake()
genirq: Consistently use '%u' format specifier for unsigned int variables
genirq: Ensure flags in lock guard is consistently initialized
genirq: Fix inverted condition in handle_nested_irq()
genirq/cpuhotplug: Fix up lock guards conversion brainf..t
genirq: Use scoped_guard() to shut clang up
genirq: Remove unused remove_percpu_irq()
genirq: Remove irq_[get|put]_desc*()
genirq/manage: Rework irq_set_irqchip_state()
genirq/manage: Rework irq_get_irqchip_state()
genirq/manage: Rework teardown_percpu_nmi()
genirq/manage: Rework prepare_percpu_nmi()
genirq/manage: Rework disable_percpu_irq()
genirq/manage: Rework irq_percpu_is_enabled()
genirq/manage: Rework enable_percpu_irq()
genirq/manage: Rework irq_set_parent()
genirq/manage: Rework can_request_irq()
...
Pull core entry code updates from Thomas Gleixner:
"Updates for the generic and architecture entry code:
- Move LoongArch and RISC-V ret_from_fork() implementations to C code
so that syscall_exit_user_mode() can be inlined
- Split the RISC-V ret_from_fork() implementation into return to user
and return to kernel, which gives a measurable performance
improvement
- Inline syscall_exit_user_mode() which benefits all architectures by
avoiding a function call and letting the compiler do better
optimizations"
* tag 'core-entry-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
LoongArch: entry: Fix include order
entry: Inline syscall_exit_to_user_mode()
LoongArch: entry: Migrate ret_from_fork() to C
riscv: entry: Split ret_from_fork() into user and kernel
riscv: entry: Convert ret_from_fork() to C
Pull perf events updates from Ingo Molnar:
"Core & generic-arch updates:
- Add support for dynamic constraints and propagate it to the Intel
driver (Kan Liang)
- Fix & enhance driver-specific throttling support (Kan Liang)
- Record sample last_period before updating on the x86 and PowerPC
platforms (Mark Barnett)
- Make perf_pmu_unregister() usable (Peter Zijlstra)
- Unify perf_event_free_task() / perf_event_exit_task_context()
(Peter Zijlstra)
- Simplify perf_event_release_kernel() and perf_event_free_task()
(Peter Zijlstra)
- Allocate non-contiguous AUX pages by default (Yabin Cui)
Uprobes updates:
- Add support to emulate NOP instructions (Jiri Olsa)
- selftests/bpf: Add 5-byte NOP uprobe trigger benchmark (Jiri Olsa)
x86 Intel PMU enhancements:
- Support Intel Auto Counter Reload [ACR] (Kan Liang)
- Add PMU support for Clearwater Forest (Dapeng Mi)
- Arch-PEBS preparatory changes: (Dapeng Mi)
- Parse CPUID archPerfmonExt leaves for non-hybrid CPUs
- Decouple BTS initialization from PEBS initialization
- Introduce pairs of PEBS static calls
x86 AMD PMU enhancements:
- Use hrtimer for handling overflows in the AMD uncore driver
(Sandipan Das)
- Prevent UMC counters from saturating (Sandipan Das)
Fixes and cleanups:
- Fix put_ctx() ordering (Frederic Weisbecker)
- Fix irq work dereferencing garbage (Frederic Weisbecker)
- Misc fixes and cleanups (Changbin Du, Frederic Weisbecker, Ian
Rogers, Ingo Molnar, Kan Liang, Peter Zijlstra, Qing Wang, Sandipan
Das, Thorsten Blum)"
* tag 'perf-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
perf/headers: Clean up <linux/perf_event.h> a bit
perf/uapi: Clean up <uapi/linux/perf_event.h> a bit
perf/uapi: Fix PERF_RECORD_SAMPLE comments in <uapi/linux/perf_event.h>
mips/perf: Remove driver-specific throttle support
xtensa/perf: Remove driver-specific throttle support
sparc/perf: Remove driver-specific throttle support
loongarch/perf: Remove driver-specific throttle support
csky/perf: Remove driver-specific throttle support
arc/perf: Remove driver-specific throttle support
alpha/perf: Remove driver-specific throttle support
perf/apple_m1: Remove driver-specific throttle support
perf/arm: Remove driver-specific throttle support
s390/perf: Remove driver-specific throttle support
powerpc/perf: Remove driver-specific throttle support
perf/x86/zhaoxin: Remove driver-specific throttle support
perf/x86/amd: Remove driver-specific throttle support
perf/x86/intel: Remove driver-specific throttle support
perf: Only dump the throttle log for the leader
perf: Fix the throttle logic for a group
perf/core: Add the is_event_in_freq_mode() helper to simplify the code
...
Pull scheduler updates from Ingo Molnar:
"Core & fair scheduler changes:
- Tweak wait_task_inactive() to force dequeue sched_delayed tasks
(John Stultz)
- Adhere to place_entity() constraints (Peter Zijlstra)
- Allow decaying util_est when util_avg > CPU capacity (Pierre
Gondois)
- Fix up wake_up_sync() vs DELAYED_DEQUEUE (Xuewen Yan)
Energy management:
- Introduce sched_update_asym_prefer_cpu() (K Prateek Nayak)
- cpufreq/amd-pstate: Update asym_prefer_cpu when core rankings
change (K Prateek Nayak)
- Align uclamp and util_est and call before freq update (Xuewen Yan)
CPU isolation:
- Make use of more than one housekeeping CPU (Phil Auld)
RT scheduler:
- Fix race in push_rt_task() (Harshit Agarwal)
- Add kernel cmdline option for rt_group_sched (Michal Koutný)
Scheduler topology support:
- Improve topology_span_sane speed (Steve Wahl)
Scheduler debugging:
- Move and extend the sched_process_exit() tracepoint (Andrii
Nakryiko)
- Add RT_GROUP WARN checks for non-root task_groups (Michal Koutný)
- Fix trace_sched_switch(.prev_state) (Peter Zijlstra)
- Untangle cond_resched() and live-patching (Peter Zijlstra)
Fixes and cleanups:
- Misc fixes and cleanups (K Prateek Nayak, Michal Koutný, Peter
Zijlstra, Xuewen Yan)"
* tag 'sched-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
sched/uclamp: Align uclamp and util_est and call before freq update
sched/util_est: Simplify condition for util_est_{en,de}queue()
sched/fair: Fixup wake_up_sync() vs DELAYED_DEQUEUE
sched,livepatch: Untangle cond_resched() and live-patching
sched/core: Tweak wait_task_inactive() to force dequeue sched_delayed tasks
sched/fair: Adhere to place_entity() constraints
sched/debug: Print the local group's asym_prefer_cpu
cpufreq/amd-pstate: Update asym_prefer_cpu when core rankings change
sched/topology: Introduce sched_update_asym_prefer_cpu()
sched/fair: Use READ_ONCE() to read sg->asym_prefer_cpu
sched/isolation: Make use of more than one housekeeping cpu
sched/rt: Fix race in push_rt_task
sched: Add annotations to RT_GROUP_SCHED fields
sched: Add RT_GROUP WARN checks for non-root task_groups
sched: Do not construct nor expose RT_GROUP_SCHED structures if disabled
sched: Bypass bandwitdh checks with runtime disabled RT_GROUP_SCHED
sched: Skip non-root task_groups with disabled RT_GROUP_SCHED
sched: Add commadline option for RT_GROUP_SCHED toggling
sched: Always initialize rt_rq's task_group
sched: Remove unneeed macro wrap
...
Pull locking updates from Ingo Molnar:
"Futexes:
- Add support for task local hash maps (Sebastian Andrzej Siewior,
Peter Zijlstra)
- Implement the FUTEX2_NUMA ABI, which feature extends the futex
interface to be NUMA-aware. On NUMA-aware futexes a second u32 word
containing the NUMA node is added to after the u32 futex value word
(Peter Zijlstra)
- Implement the FUTEX2_MPOL ABI, which feature extends the futex
interface to be mempolicy-aware as well, to further refine futex
node mappings and lookups (Peter Zijlstra)
Locking primitives:
- Misc cleanups (Andy Shevchenko, Borislav Petkov, Colin Ian King,
Ingo Molnar, Nam Cao, Peter Zijlstra)
Lockdep:
- Prevent abuse of lockdep subclasses (Waiman Long)
- Add number of dynamic keys to /proc/lockdep_stats (Waiman Long)
Plus misc cleanups and fixes"
* tag 'locking-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
selftests/futex: Fix spelling mistake "unitiliazed" -> "uninitialized"
futex: Correct the kernedoc return value for futex_wait_setup().
tools headers: Synchronize prctl.h ABI header
futex: Use RCU_INIT_POINTER() in futex_mm_init().
selftests/futex: Use TAP output in futex_numa_mpol
selftests/futex: Use TAP output in futex_priv_hash
futex: Fix kernel-doc comments
futex: Relax the rcu_assign_pointer() assignment of mm->futex_phash in futex_mm_init()
futex: Fix outdated comment in struct restart_block
locking/lockdep: Add number of dynamic keys to /proc/lockdep_stats
locking/lockdep: Prevent abuse of lockdep subclass
locking/lockdep: Move hlock_equal() to the respective #ifdeffery
futex,selftests: Add another FUTEX2_NUMA selftest
selftests/futex: Add futex_numa_mpol
selftests/futex: Add futex_priv_hash
selftests/futex: Build without headers nonsense
tools/perf: Allow to select the number of hash buckets
tools headers: Synchronize prctl.h ABI header
futex: Implement FUTEX2_MPOL
futex: Implement FUTEX2_NUMA
...
Pull RCU updates from Joel Fernandes:
- Removed swake_up_one_online() workaround
- Reverted an incorrect rcuog wake-up fix from offline softirq
- Rust RCU Guard methods marked as inline
- Updated MAINTAINERS with Joel’s and Zqiang's new email address
- Replaced magic constant in rcu_seq_done_exact() with named constant
- Added warning mechanism to validate rcu_seq_done_exact()
- Switched SRCU polling API to use rcu_seq_done_exact()
- Commented on redundant delta check in rcu_seq_done_exact()
- Made ->gpwrap tests in rcutorture more frequent
- Fixed reuse of ARM64 images in rcutorture
- rcutorture improved to check Kconfig and reader conflict handling
- Extracted logic from rcu_torture_one_read() for clarity
- Updated LWN RCU API documentation links
- Enabled --do-rt in torture.sh for CONFIG_PREEMPT_RT
- Added tests for SRCU up/down reader primitives
- Added comments and delays checks in rcutorture
- Deprecated srcu_read_lock_lite() and srcu_read_unlock_lite() via checkpatch
- Added --do-normal and --do-no-normal to torture.sh
- Added RCU Rust binding tests to torture.sh
- Reduced CPU overcommit and removed MAXSMP/CPUMASK_OFFSTACK in TREE01
- Replaced kmalloc() with kcalloc() in rcuscale
- Refined listRCU example code for stale data elimination
- Fixed hardirq count bug for x86 in cpu_stall_cputime
- Added safety checks in rcu/nocb for offloaded rdp access
- Other miscellaneous changes
* tag 'next.2025.05.17a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (27 commits)
rcutorture: Fix issue with re-using old images on ARM64
rcutorture: Remove MAXSMP and CPUMASK_OFFSTACK from TREE01
rcutorture: Reduce TREE01 CPU overcommit
torture: Check for "Call trace:" as well as "Call Trace:"
rcutorture: Perform more frequent testing of ->gpwrap
torture: Add testing of RCU's Rust bindings to torture.sh
torture: Add --do-{,no-}normal to torture.sh
checkpatch: Deprecate srcu_read_lock_lite() and srcu_read_unlock_lite()
rcutorture: Comment invocations of tick_dep_set_task()
rcu/nocb: Add Safe checks for access offloaded rdp
rcuscale: using kcalloc() to relpace kmalloc()
doc/RCU/listRCU: refine example code for eliminating stale data
doc: Update LWN RCU API links in whatisRCU.rst
Revert "rcu/nocb: Fix rcuog wake-up from offline softirq"
rust: sync: rcu: Mark Guard methods as inline
rcu/cpu_stall_cputime: fix the hardirq count for x86 architecture
rcu: Remove swake_up_one_online() bandaid
MAINTAINERS: Update Zqiang's email address
rcutorture: Make torture.sh --do-rt use CONFIG_PREEMPT_RT
srcu: Use rcu_seq_done_exact() for polling API
...
Pull block updates from Jens Axboe:
- ublk updates:
- Add support for updating the size of a ublk instance
- Zero-copy improvements
- Auto-registering of buffers for zero-copy
- Series simplifying and improving GET_DATA and request lookup
- Series adding quiesce support
- Lots of selftests additions
- Various cleanups
- NVMe updates via Christoph:
- add per-node DMA pools and use them for PRP/SGL allocations
(Caleb Sander Mateos, Keith Busch)
- nvme-fcloop refcounting fixes (Daniel Wagner)
- support delayed removal of the multipath node and optionally
support the multipath node for private namespaces (Nilay Shroff)
- support shared CQs in the PCI endpoint target code (Wilfred
Mallawa)
- support admin-queue only authentication (Hannes Reinecke)
- use the crc32c library instead of the crypto API (Eric Biggers)
- misc cleanups (Christoph Hellwig, Marcelo Moreira, Hannes
Reinecke, Leon Romanovsky, Gustavo A. R. Silva)
- MD updates via Yu:
- Fix that normal IO can be starved by sync IO, found by mkfs on
newly created large raid5, with some clean up patches for bdev
inflight counters
- Clean up brd, getting rid of atomic kmaps and bvec poking
- Add loop driver specifically for zoned IO testing
- Eliminate blk-rq-qos calls with a static key, if not enabled
- Improve hctx locking for when a plug has IO for multiple queues
pending
- Remove block layer bouncing support, which in turn means we can
remove the per-node bounce stat as well
- Improve blk-throttle support
- Improve delay support for blk-throttle
- Improve brd discard support
- Unify IO scheduler switching. This should also fix a bunch of lockdep
warnings we've been seeing, after enabling lockdep support for queue
freezing/unfreezeing
- Add support for block write streams via FDP (flexible data placement)
on NVMe
- Add a bunch of block helpers, facilitating the removal of a bunch of
duplicated boilerplate code
- Remove obsolete BLK_MQ pci and virtio Kconfig options
- Add atomic/untorn write support to blktrace
- Various little cleanups and fixes
* tag 'for-6.16/block-20250523' of git://git.kernel.dk/linux: (186 commits)
selftests: ublk: add test for UBLK_F_QUIESCE
ublk: add feature UBLK_F_QUIESCE
selftests: ublk: add test case for UBLK_U_CMD_UPDATE_SIZE
traceevent/block: Add REQ_ATOMIC flag to block trace events
ublk: run auto buf unregisgering in same io_ring_ctx with registering
io_uring: add helper io_uring_cmd_ctx_handle()
ublk: remove io argument from ublk_auto_buf_reg_fallback()
ublk: handle ublk_set_auto_buf_reg() failure correctly in ublk_fetch()
selftests: ublk: add test for covering UBLK_AUTO_BUF_REG_FALLBACK
selftests: ublk: support UBLK_F_AUTO_BUF_REG
ublk: support UBLK_AUTO_BUF_REG_FALLBACK
ublk: register buffer to local io_uring with provided buf index via UBLK_F_AUTO_BUF_REG
ublk: prepare for supporting to register request buffer automatically
ublk: convert to refcount_t
selftests: ublk: make IO & device removal test more stressful
nvme: rename nvme_mpath_shutdown_disk to nvme_mpath_remove_disk
nvme: introduce multipath_always_on module param
nvme-multipath: introduce delayed removal of the multipath head node
nvme-pci: derive and better document max segments limits
nvme-pci: use struct_size for allocation struct nvme_dev
...
Pull pidfs updates from Christian Brauner:
"Features:
- Allow handing out pidfds for reaped tasks for AF_UNIX SO_PEERPIDFD
socket option
SO_PEERPIDFD is a socket option that allows to retrieve a pidfd for
the process that called connect() or listen(). This is heavily used
to safely authenticate clients in userspace avoiding security bugs
due to pid recycling races (dbus, polkit, systemd, etc.)
SO_PEERPIDFD currently doesn't support handing out pidfds if the
sk->sk_peer_pid thread-group leader has already been reaped. In
this case it currently returns EINVAL. Userspace still wants to get
a pidfd for a reaped process to have a stable handle it can pass
on. This is especially useful now that it is possible to retrieve
exit information through a pidfd via the PIDFD_GET_INFO ioctl()'s
PIDFD_INFO_EXIT flag
Another summary has been provided by David Rheinsberg:
> A pidfd can outlive the task it refers to, and thus user-space
> must already be prepared that the task underlying a pidfd is
> gone at the time they get their hands on the pidfd. For
> instance, resolving the pidfd to a PID via the fdinfo must be
> prepared to read `-1`.
>
> Despite user-space knowing that a pidfd might be stale, several
> kernel APIs currently add another layer that checks for this. In
> particular, SO_PEERPIDFD returns `EINVAL` if the peer-task was
> already reaped, but returns a stale pidfd if the task is reaped
> immediately after the respective alive-check.
>
> This has the unfortunate effect that user-space now has two ways
> to check for the exact same scenario: A syscall might return
> EINVAL/ESRCH/... *or* the pidfd might be stale, even though
> there is no particular reason to distinguish both cases. This
> also propagates through user-space APIs, which pass on pidfds.
> They must be prepared to pass on `-1` *or* the pidfd, because
> there is no guaranteed way to get a stale pidfd from the kernel.
>
> Userspace must already deal with a pidfd referring to a reaped
> task as the task may exit and get reaped at any time will there
> are still many pidfds referring to it
In order to allow handing out reaped pidfd SO_PEERPIDFD needs to
ensure that PIDFD_INFO_EXIT information is available whenever a
pidfd for a reaped task is created by PIDFD_INFO_EXIT. The uapi
promises that reaped pidfds are only handed out if it is guaranteed
that the caller sees the exit information:
TEST_F(pidfd_info, success_reaped)
{
struct pidfd_info info = {
.mask = PIDFD_INFO_CGROUPID | PIDFD_INFO_EXIT,
};
/*
* Process has already been reaped and PIDFD_INFO_EXIT been set.
* Verify that we can retrieve the exit status of the process.
*/
ASSERT_EQ(ioctl(self->child_pidfd4, PIDFD_GET_INFO, &info), 0);
ASSERT_FALSE(!!(info.mask & PIDFD_INFO_CREDS));
ASSERT_TRUE(!!(info.mask & PIDFD_INFO_EXIT));
ASSERT_TRUE(WIFEXITED(info.exit_code));
ASSERT_EQ(WEXITSTATUS(info.exit_code), 0);
}
To hand out pidfds for reaped processes we thus allocate a pidfs
entry for the relevant sk->sk_peer_pid at the time the
sk->sk_peer_pid is stashed and drop it when the socket is
destroyed. This guarantees that exit information will always be
recorded for the sk->sk_peer_pid task and we can hand out pidfds
for reaped processes
- Hand a pidfd to the coredump usermode helper process
Give userspace a way to instruct the kernel to install a pidfd for
the crashing process into the process started as a usermode helper.
There's still tricky race-windows that cannot be easily or
sometimes not closed at all by userspace. There's various ways like
looking at the start time of a process to make sure that the
usermode helper process is started after the crashing process but
it's all very very brittle and fraught with peril
The crashed-but-not-reaped process can be killed by userspace
before coredump processing programs like systemd-coredump have had
time to manually open a PIDFD from the PID the kernel provides
them, which means they can be tricked into reading from an
arbitrary process, and they run with full privileges as they are
usermode helper processes
Even if that specific race-window wouldn't exist it's still the
safest and cleanest way to let the kernel provide the pidfd
directly instead of requiring userspace to do it manually. In
parallel with this commit we already have systemd adding support
for this in [1]
When the usermode helper process is forked we install a pidfd file
descriptor three into the usermode helper's file descriptor table
so it's available to the exec'd program
Since usermode helpers are either children of the system_unbound_wq
workqueue or kthreadd we know that the file descriptor table is
empty and can thus always use three as the file descriptor number
Note, that we'll install a pidfd for the thread-group leader even
if a subthread is calling do_coredump(). We know that task linkage
hasn't been removed yet and even if this @current isn't the actual
thread-group leader we know that the thread-group leader cannot be
reaped until
@current has exited
- Allow telling when a task has not been found from finding the wrong
task when creating a pidfd
We currently report EINVAL whenever a struct pid has no tasked
attached anymore thereby conflating two concepts:
(1) The task has already been reaped
(2) The caller requested a pidfd for a thread-group leader but the
pid actually references a struct pid that isn't used as a
thread-group leader
This is causing issues for non-threaded workloads as in where they
expect ESRCH to be reported, not EINVAL
So allow userspace to reliably distinguish between (1) and (2)
- Make it possible to detect when a pidfs entry would outlive the
struct pid it pinned
- Add a range of new selftests
Cleanups:
- Remove unneeded NULL check from pidfd_prepare() for passed struct
pid
- Avoid pointless reference count bump during release_task()
Fixes:
- Various fixes to the pidfd and coredump selftests
- Fix error handling for replace_fd() when spawning coredump usermode
helper"
* tag 'vfs-6.16-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
pidfs: detect refcount bugs
coredump: hand a pidfd to the usermode coredump helper
coredump: fix error handling for replace_fd()
pidfs: move O_RDWR into pidfs_alloc_file()
selftests: coredump: Raise timeout to 2 minutes
selftests: coredump: Fix test failure for slow machines
selftests: coredump: Properly initialize pointer
net, pidfs: enable handing out pidfds for reaped sk->sk_peer_pid
pidfs: get rid of __pidfd_prepare()
net, pidfs: prepare for handing out pidfds for reaped sk->sk_peer_pid
pidfs: register pid in pidfs
net, pidfd: report EINVAL for ESRCH
release_task: kill the no longer needed get/put_pid(thread_pid)
pidfs: ensure consistent ENOENT/ESRCH reporting
exit: move wake_up_all() pidfd waiters into __unhash_process()
selftest/pidfd: add test for thread-group leader pidfd open for thread
pidfd: improve uapi when task isn't found
pidfd: remove unneeded NULL check from pidfd_prepare()
selftests/pidfd: adapt to recent changes
Pull vfs freezing updates from Christian Brauner:
"This contains various filesystem freezing related work for this cycle:
- Allow the power subsystem to support filesystem freeze for suspend
and hibernate.
Now all the pieces are in place to actually allow the power
subsystem to freeze/thaw filesystems during suspend/resume.
Filesystems are only frozen and thawed if the power subsystem does
actually own the freeze.
If the filesystem is already frozen by the time we've frozen all
userspace processes we don't care to freeze it again. That's
userspace's job once the process resumes. We only actually freeze
filesystems if we absolutely have to and we ignore other failures
to freeze.
We could bubble up errors and fail suspend/resume if the error
isn't EBUSY (aka it's already frozen) but I don't think that this
is worth it. Filesystem freezing during suspend/resume is
best-effort. If the user has 500 ext4 filesystems mounted and 4
fail to freeze for whatever reason then we simply skip them.
What we have now is already a big improvement and let's see how we
fare with it before making our lives even harder (and uglier) than
we have to.
- Allow efivars to support freeze and thaw
Allow efivarfs to partake to resync variable state during system
hibernation and suspend. Add freeze/thaw support.
This is a pretty straightforward implementation. We simply add
regular freeze/thaw support for both userspace and the kernel.
efivars is the first pseudofilesystem that adds support for
filesystem freezing and thawing.
The simplicity comes from the fact that we simply always resync
variable state after efivarfs has been frozen. It doesn't matter
whether that's because of suspend, userspace initiated freeze or
hibernation. Efivars is simple enough that it doesn't matter that
we walk all dentries. There are no directories and there aren't
insane amounts of entries and both freeze/thaw are already
heavy-handed operations. If userspace initiated a freeze/thaw cycle
they would need CAP_SYS_ADMIN in the initial user namespace (as
that's where efivarfs is mounted) so it can't be triggered by
random userspace. IOW, we really really don't care"
* tag 'vfs-6.16-rc1.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
f2fs: fix freezing filesystem during resize
kernfs: add warning about implementing freeze/thaw
efivarfs: support freeze/thaw
power: freeze filesystems during suspend/resume
libfs: export find_next_child()
super: add filesystem freezing helpers for suspend and hibernate
gfs2: pass through holder from the VFS for freeze/thaw
super: use common iterator (Part 2)
super: use a common iterator (Part 1)
super: skip dying superblocks early
super: simplify user_get_super()
super: remove pointless s_root checks
fs: allow all writers to be frozen
locking/percpu-rwsem: add freezable alternative to down_read
Pull misc vfs updates from Christian Brauner:
"This contains the usual selections of misc updates for this cycle.
Features:
- Use folios for symlinks in the page cache
FUSE already uses folios for its symlinks. Mirror that conversion
in the generic code and the NFS code. That lets us get rid of a few
folio->page->folio conversions in this path, and some of the few
remaining users of read_cache_page() / read_mapping_page()
- Try and make a few filesystem operations killable on the VFS
inode->i_mutex level
- Add sysctl vfs_cache_pressure_denom for bulk file operations
Some workloads need to preserve more dentries than we currently
allow through out sysctl interface
A HDFS servers with 12 HDDs per server, on a HDFS datanode startup
involves scanning all files and caching their metadata (including
dentries and inodes) in memory. Each HDD contains approximately 2
million files, resulting in a total of ~20 million cached dentries
after initialization
To minimize dentry reclamation, they set vfs_cache_pressure to 1.
Despite this configuration, memory pressure conditions can still
trigger reclamation of up to 50% of cached dentries, reducing the
cache from 20 million to approximately 10 million entries. During
the subsequent cache rebuild period, any HDFS datanode restart
operation incurs substantial latency penalties until full cache
recovery completes
To maintain service stability, more dentries need to be preserved
during memory reclamation. The current minimum reclaim ratio (1/100
of total dentries) remains too aggressive for such workload. This
patch introduces vfs_cache_pressure_denom for more granular cache
pressure control
The configuration [vfs_cache_pressure=1,
vfs_cache_pressure_denom=10000] effectively maintains the full 20
million dentry cache under memory pressure, preventing datanode
restart performance degradation
- Avoid some jumps in inode_permission() using likely()/unlikely()
- Avid a memory access which is most likely a cache miss when
descending into devcgroup_inode_permission()
- Add fastpath predicts for stat() and fdput()
- Anonymous inodes currently don't come with a proper mode causing
issues in the kernel when we want to add useful VFS debug assert.
Fix that by giving them a proper mode and masking it off when we
report it to userspace which relies on them not having any mode
- Anonymous inodes currently allow to change inode attributes because
the VFS falls back to simple_setattr() if i_op->setattr isn't
implemented. This means the ownership and mode for every single
user of anon_inode_inode can be changed. Block that as it's either
useless or actively harmful. If specific ownership is needed the
respective subsystem should allocate anonymous inodes from their
own private superblock
- Raise SB_I_NODEV and SB_I_NOEXEC on the anonymous inode superblock
- Add proper tests for anonymous inode behavior
- Make it easy to detect proper anonymous inodes and to ensure that
we can detect them in codepaths such as readahead()
Cleanups:
- Port pidfs to the new anon_inode_{g,s}etattr() helpers
- Try to remove the uselib() system call
- Add unlikely branch hint return path for poll
- Add unlikely branch hint on return path for core_sys_select
- Don't allow signals to interrupt getdents copying for fuse
- Provide a size hint to dir_context for during readdir()
- Use writeback_iter directly in mpage_writepages
- Update compression and mtime descriptions in initramfs
documentation
- Update main netfs API document
- Remove useless plus one in super_cache_scan()
- Remove unnecessary NULL-check guards during setns()
- Add separate separate {get,put}_cgroup_ns no-op cases
Fixes:
- Fix typo in root= kernel parameter description
- Use KERN_INFO for infof()|info_plog()|infofc()
- Correct comments of fs_validate_description()
- Mark an unlikely if condition with unlikely() in
vfs_parse_monolithic_sep()
- Delete macro fsparam_u32hex()
- Remove unused and problematic validate_constant_table()
- Fix potential unsigned integer underflow in fs_name()
- Make file-nr output the total allocated file handles"
* tag 'vfs-6.16-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (43 commits)
fs: Pass a folio to page_put_link()
nfs: Use a folio in nfs_get_link()
fs: Convert __page_get_link() to use a folio
fs/read_write: make default_llseek() killable
fs/open: make do_truncate() killable
fs/open: make chmod_common() and chown_common() killable
include/linux/fs.h: add inode_lock_killable()
readdir: supply dir_context.count as readdir buffer size hint
vfs: Add sysctl vfs_cache_pressure_denom for bulk file operations
fuse: don't allow signals to interrupt getdents copying
Documentation: fix typo in root= kernel parameter description
include/cgroup: separate {get,put}_cgroup_ns no-op case
kernel/nsproxy: remove unnecessary guards
fs: use writeback_iter directly in mpage_writepages
fs: remove useless plus one in super_cache_scan()
fs: add S_ANON_INODE
fs: remove uselib() system call
device_cgroup: avoid access to ->i_rdev in the common case in devcgroup_inode_permission()
fs/fs_parse: Remove unused and problematic validate_constant_table()
fs: touch up predicts in inode_permission()
...
Pull vfs directory lookup updates from Christian Brauner:
"This contains cleanups for the lookup_one*() family of helpers.
We expose a set of functions with names containing "lookup_one_len"
and others without the "_len". This difference has nothing to do with
"len". It's rater a historical accident that can be confusing.
The functions without "_len" take a "mnt_idmap" pointer. This is found
in the "vfsmount" and that is an important question when choosing
which to use: do you have a vfsmount, or are you "inside" the
filesystem. A related question is "is permission checking relevant
here?".
nfsd and cachefiles *do* have a vfsmount but *don't* use the non-_len
functions. They pass nop_mnt_idmap and refuse to work on filesystems
which have any other idmap.
This work changes nfsd and cachefile to use the lookup_one family of
functions and to explictily pass &nop_mnt_idmap which is consistent
with all other vfs interfaces used where &nop_mnt_idmap is explicitly
passed.
The remaining uses of the "_one" functions do not require permission
checks so these are renamed to be "_noperm" and the permission
checking is removed.
This series also changes these lookup function to take a qstr instead
of separate name and len. In many cases this simplifies the call"
* tag 'vfs-6.16-rc1.async.dir' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
VFS: change lookup_one_common and lookup_noperm_common to take a qstr
Use try_lookup_noperm() instead of d_hash_and_lookup() outside of VFS
VFS: rename lookup_one_len family to lookup_noperm and remove permission check
cachefiles: Use lookup_one() rather than lookup_one_len()
nfsd: Use lookup_one() rather than lookup_one_len()
VFS: improve interface for lookup_one functions
Pull hotfixes from Andrew Morton:
"22 hotfixes.
13 are cc:stable and the remainder address post-6.14 issues or aren't
considered necessary for -stable kernels. 19 are for MM"
* tag 'mm-hotfixes-stable-2025-05-25-00-58' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (22 commits)
mailmap: add Jarkko's employer email address
mm: fix copy_vma() error handling for hugetlb mappings
memcg: always call cond_resched() after fn()
mm/hugetlb: fix kernel NULL pointer dereference when replacing free hugetlb folios
mm: vmalloc: only zero-init on vrealloc shrink
mm: vmalloc: actually use the in-place vrealloc region
alloc_tag: allocate percpu counters for module tags dynamically
module: release codetag section when module load fails
mm/cma: make detection of highmem_start more robust
MAINTAINERS: add mm memory policy section
MAINTAINERS: add mm ksm section
kasan: avoid sleepable page allocation from atomic context
highmem: add folio_test_partial_kmap()
MAINTAINERS: add hung-task detector section
taskstats: fix struct taskstats breaks backward compatibility since version 15
mm/truncate: fix out-of-bounds when doing a right-aligned split
MAINTAINERS: add mm reclaim section
MAINTAINERS: update page allocator section
mm: fix VM_UFFD_MINOR == VM_SHADOW_STACK on USERFAULTFD=y && ARM64_GCS=y
mm: mmap: map MAP_STACK to VM_NOHUGEPAGE only if THP is enabled
...
Filesystems like XFS can implement atomic write I/O using either
REQ_ATOMIC flag set in the bio or via CoW operation. It will be useful
if we have a flag in trace events to distinguish between the two. This
patch adds char 'U' (Untorn writes) to rwbs field of the trace events
if REQ_ATOMIC flag is set in the bio.
<W/ REQ_ATOMIC>
=================
xfs_io-4238 [009] ..... 4148.126843: block_rq_issue: 259,0 WFSU 16384 () 768 + 32 none,0,0 [xfs_io]
<idle>-0 [009] d.h1. 4148.129864: block_rq_complete: 259,0 WFSU () 768 + 32 none,0,0 [0]
<W/O REQ_ATOMIC>
===============
xfs_io-4237 [010] ..... 4143.325616: block_rq_issue: 259,0 WS 16384 () 768 + 32 none,0,0 [xfs_io]
<idle>-0 [010] d.H1. 4143.329138: block_rq_complete: 259,0 WS () 768 + 32 none,0,0 [0]
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://lore.kernel.org/r/44317cb2ec4588f6a2c1501a96684e6a1196e8ba.1747921498.git.ritesh.list@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The PERF_RECORD_THROTTLE records are dumped for all throttled events.
It's not necessary for group events, which are throttled altogether.
Optimize it by only dump the throttle log for the leader.
The sample right after the THROTTLE record must be generated by the
actual target event. It is good enough for the perf tool to locate the
actual target event.
Suggested-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250520181644.2673067-3-kan.liang@linux.intel.com
The current throttle logic doesn't work well with a group, e.g., the
following sampling-read case.
$ perf record -e "{cycles,cycles}:S" ...
$ perf report -D | grep THROTTLE | tail -2
THROTTLE events: 426 ( 9.0%)
UNTHROTTLE events: 425 ( 9.0%)
$ perf report -D | grep PERF_RECORD_SAMPLE -a4 | tail -n 5
0 1020120874009167 0x74970 [0x68]: PERF_RECORD_SAMPLE(IP, 0x1):
... sample_read:
.... group nr 2
..... id 0000000000000327, value 000000000cbb993a, lost 0
..... id 0000000000000328, value 00000002211c26df, lost 0
The second cycles event has a much larger value than the first cycles
event in the same group.
The current throttle logic in the generic code only logs the THROTTLE
event. It relies on the specific driver implementation to disable
events. For all ARCHs, the implementation is similar. Only the event is
disabled, rather than the group.
The logic to disable the group should be generic for all ARCHs. Add the
logic in the generic code. The following patch will remove the buggy
driver-specific implementation.
The throttle only happens when an event is overflowed. Stop the entire
group when any event in the group triggers the throttle.
The MAX_INTERRUPTS is set to all throttle events.
The unthrottled could happen in 3 places.
- event/group sched. All events in the group are scheduled one by one.
All of them will be unthrottled eventually. Nothing needs to be
changed.
- The perf_adjust_freq_unthr_events for each tick. Needs to restart the
group altogether.
- The __perf_event_period(). The whole group needs to be restarted
altogether as well.
With the fix,
$ sudo perf report -D | grep PERF_RECORD_SAMPLE -a4 | tail -n 5
0 3573470770332 0x12f5f8 [0x70]: PERF_RECORD_SAMPLE(IP, 0x2):
... sample_read:
.... group nr 2
..... id 0000000000000a28, value 00000004fd3dfd8f, lost 0
..... id 0000000000000a29, value 00000004fd3dfd8f, lost 0
Suggested-by: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250520181644.2673067-2-kan.liang@linux.intel.com
The commit dfa0a574cb ("sched/uclamg: Handle delayed dequeue")
has add the sched_delayed check to prevent double uclamp_dec/inc.
However, it put the uclamp_rq_inc() after enqueue_task().
This may lead to the following issues:
When a task with uclamp goes through enqueue_task() and could trigger
cpufreq update, its uclamp won't even be considered in the cpufreq
update. It is only after enqueue will the uclamp be added to rq
buckets, and cpufreq will only pick it up at the next update.
This could cause a delay in frequency updating. It may affect
the performance(uclamp_min > 0) or power(uclamp_max < 1024).
So, just like util_est, put the uclamp_rq_inc() before enqueue_task().
And as for the sched_delayed_task, same as util_est, using the
sched_delayed flag to prevent inc the sched_delayed_task's uclamp,
using the ENQUEUE_DELAYED flag to allow inc the sched_delayed_task's uclamp
which is being woken up.
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20250417043457.10632-3-xuewen.yan@unisoc.com
To prevent double enqueue/dequeue of the util-est for sched_delayed tasks,
commit 729288bc68 ("kernel/sched: Fix util_est accounting for DELAY_DEQUEUE")
added the corresponding check. This check excludes double en/dequeue during
task migration and priority changes.
In fact, these conditions can be simplified.
For util_est_dequeue, we know that sched_delayed flag is set in dequeue_entity.
When the task is sleeping, we need to call util_est_dequeue to subtract
util-est from the cfs_rq. At this point, sched_delayed has not yet been set.
If we find that sched_delayed is already set, it indicates that this task
has already called dequeue_task_fair once. In this case, there is no need to
call util_est_dequeue again. Therefore, simply checking the sched_delayed flag
should be sufficient to prevent unnecessary util_est updates during the dequeue.
For util_est_enqueue, our goal is to add the util_est to the cfs_rq
when task enqueue. However, we don't want to add the util_est of a
sched_delayed task to the cfs_rq because the task is sleeping.
Therefore, we can exclude the util_est_enqueue for sched_delayed tasks
by checking the sched_delayed flag. However, when waking up a delayed task,
the sched_delayed flag is cleared after util_est_enqueue. As a result,
if we only check the sched_delayed flag, we would miss the util_est_enqueue.
Since waking up a sched_delayed task calls enqueue_task with the ENQUEUE_DELAYED flag,
we can determine whether to call util_est_enqueue by checking if the
enqueue_flag contains ENQUEUE_DELAYED.
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20250417043457.10632-2-xuewen.yan@unisoc.com
Delayed dequeued feature keeps a sleeping task enqueued until its
lag has elapsed. As a result, it stays also visible in rq->nr_running.
So when in wake_affine_idle(), we should use the real running-tasks
in rq to check whether we should place the wake-up task to
current cpu.
On the other hand, add a helper function to return the nr-delayed.
Fixes: 152e11f6df ("sched/fair: Implement delayed dequeue")
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Reviewed-and-tested-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20250303105241.17251-2-xuewen.yan@unisoc.com
Pull crypto fixes from Herbert Xu:
"This fixes a regression in padata as well as an ancient double-free
bug in af_alg"
* tag 'v6.15-p7' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: algif_hash - fix double free in hash_accept
padata: do not leak refcount in reorder_work
A recent patch that addressed a UAF introduced a reference count leak:
the parallel_data refcount is incremented unconditionally, regardless
of the return value of queue_work(). If the work item is already queued,
the incremented refcount is never decremented.
Fix this by checking the return value of queue_work() and decrementing
the refcount when necessary.
Resolves:
Unreferenced object 0xffff9d9f421e3d80 (size 192):
comm "cryptomgr_probe", pid 157, jiffies 4294694003
hex dump (first 32 bytes):
80 8b cf 41 9f 9d ff ff b8 97 e0 89 ff ff ff ff ...A............
d0 97 e0 89 ff ff ff ff 19 00 00 00 1f 88 23 00 ..............#.
backtrace (crc 838fb36):
__kmalloc_cache_noprof+0x284/0x320
padata_alloc_pd+0x20/0x1e0
padata_alloc_shell+0x3b/0xa0
0xffffffffc040a54d
cryptomgr_probe+0x43/0xc0
kthread+0xf6/0x1f0
ret_from_fork+0x2f/0x50
ret_from_fork_asm+0x1a/0x30
Fixes: dd7d37ccf6 ("padata: avoid UAF for reorder_work")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dominik Grzegorzek <dominik.grzegorzek@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull hotfixes from Andrew Morton:
"Nine singleton hotfixes, all MM. Four are cc:stable"
* tag 'mm-hotfixes-stable-2025-05-17-09-41' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm: userfaultfd: correct dirty flags set for both present and swap pte
zsmalloc: don't underflow size calculation in zs_obj_write()
mm/page_alloc: fix race condition in unaccepted memory handling
mm/page_alloc: ensure try_alloc_pages() plays well with unaccepted memory
MAINTAINERS: add mm GUP section
mm/codetag: move tag retrieval back upfront in __free_pages()
mm/memory: fix mapcount / refcount sanity check for mTHP reuse
kernel/fork: only call untrack_pfn_clear() on VMAs duplicated for fork()
mm: hugetlb: fix incorrect fallback for subpool
Creating an irq domain that serves as an MSI parent requires
a substantial amount of esoteric boiler-plate code, some of
which is often provided twice (such as the bus token).
To make things a bit simpler for the unsuspecting MSI tinkerer,
provide a helper that does it for them, and serves as documentation
of what needs to be provided.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250513172819.2216709-3-maz@kernel.org
irqdomain.c's kernel-doc exists, but is not plugged into Documentation/
yet.
Before plugging it in, fix it first: irq_domain_get_irq_data() and
irq_domain_set_info() were documented twice. Identically, by both
definitions for CONFIG_IRQ_DOMAIN_HIERARCHY and !CONFIG_IRQ_DOMAIN_HIERARCHY.
Therefore, switch the second kernel-doc into an ordinary comment -- change
"/**" to simple "/*". This avoids sphinx's: WARNING: Duplicate C
declaration
Next, in commit b7b377332b ("irqdomain: Fix the kernel-doc and plug it
into Documentation"), irqdomain.h's (header) kernel-doc was added into
core-api/genericirq.rst. But given the amount of irqdomain functions and
structures, move all these to core-api/irq/irq-domain.rst now.
Finally, add these newly fixed irqdomain.c's (source) docs there as
well.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250319092951.37667-58-jirislaby@kernel.org
Most irq_domain_add_*() functions are unused now, so drop them. The
remaining ones are moved to the deprecated section and will be removed
during the merge window after the patches in various trees have been
merged.
Note: The Chinese docs are touched but unfinished. I cannot parse those.
[ tglx: Remove the leftover in irq-domain.rst and handle merge logistics ]
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250319092951.37667-41-jirislaby@kernel.org
All uses of of_node_to_fwnode() in non-irqdomain code were changed to
"officially" defined of_fwnode_handle(). Therefore, the former can be
dropped along with the last uses in the irqdomain code.
Due to merge logistics the inline cannot be dropped immediately. Move it to
a deprecated section, which will be removed during the merge window.
[ tglx: Handle merge logistics ]
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250319092951.37667-12-jirislaby@kernel.org
Currently, the ->gpwrap is not tested (at all per my testing) due to the
requirement of a large delta between a CPU's rdp->gp_seq and its node's
rnp->gpseq.
This results in no testing of ->gpwrap being set. This patch by default
adds 5 minutes of testing with ->gpwrap forced by lowering the delta
between rdp->gp_seq and rnp->gp_seq to just 8 GPs. All of this is
configurable, including the active time for the setting and a full
testing cycle.
By default, the first 25 minutes of a test will have the _default_
behavior there is right now (ULONG_MAX / 4) delta. Then for 5 minutes,
we switch to a smaller delta causing 1-2 wraps in 5 minutes. I believe
this is reasonable since we at least add a little bit of testing for
usecases where ->gpwrap is set.
[ Apply fix for Dan Carpenter's bug report on init path cleanup. ]
[ Apply kernel doc warning fix from Akira Yokosawa. ]
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
The rcu_torture_reader() and rcu_torture_fwd_prog_cr() functions
run CPU-bound for extended periods of time (tens or even
hundreds of milliseconds), so they invoke tick_dep_set_task() and
tick_dep_clear_task() to ensure that the scheduling-clock tick helps
move grace periods forward.
So why doesn't rcu_torture_fwd_prog_nr() also invoke tick_dep_set_task()
and tick_dep_clear_task()? Because the point of this function is to test
RCU's ability to (eventually) force grace periods forward even when the
tick has been disabled during long CPU-bound kernel execution.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
For built with CONFIG_PROVE_RCU=y and CONFIG_PREEMPT_RT=y kernels,
Disable BH does not change the SOFTIRQ corresponding bits in
preempt_count(), but change current->softirq_disable_cnt, this
resulted in the following splat:
WARNING: suspicious RCU usage
kernel/rcu/tree_plugin.h:36 Unsafe read of RCU_NOCB offloaded state!
stack backtrace:
CPU: 0 UID: 0 PID: 22 Comm: rcuc/0
Call Trace:
[ 0.407907] <TASK>
[ 0.407910] dump_stack_lvl+0xbb/0xd0
[ 0.407917] dump_stack+0x14/0x20
[ 0.407920] lockdep_rcu_suspicious+0x133/0x210
[ 0.407932] rcu_rdp_is_offloaded+0x1c3/0x270
[ 0.407939] rcu_core+0x471/0x900
[ 0.407942] ? lockdep_hardirqs_on+0xd5/0x160
[ 0.407954] rcu_cpu_kthread+0x25f/0x870
[ 0.407959] ? __pfx_rcu_cpu_kthread+0x10/0x10
[ 0.407966] smpboot_thread_fn+0x34c/0xa50
[ 0.407970] ? trace_preempt_on+0x54/0x120
[ 0.407977] ? __pfx_smpboot_thread_fn+0x10/0x10
[ 0.407982] kthread+0x40e/0x840
[ 0.407990] ? __pfx_kthread+0x10/0x10
[ 0.407994] ? rt_spin_unlock+0x4e/0xb0
[ 0.407997] ? rt_spin_unlock+0x4e/0xb0
[ 0.408000] ? __pfx_kthread+0x10/0x10
[ 0.408006] ? __pfx_kthread+0x10/0x10
[ 0.408011] ret_from_fork+0x40/0x70
[ 0.408013] ? __pfx_kthread+0x10/0x10
[ 0.408018] ret_from_fork_asm+0x1a/0x30
[ 0.408042] </TASK>
Currently, triggering an rdp offloaded state change need the
corresponding rdp's CPU goes offline, and at this time the rcuc
kthreads has already in parking state. this means the corresponding
rcuc kthreads can safely read offloaded state of rdp while it's
corresponding cpu is online.
This commit therefore add softirq_count() check for
Preempt-RT kernels.
Suggested-by: Joel Fernandes <joelagnelf@nvidia.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
perf always allocates contiguous AUX pages based on aux_watermark.
However, this contiguous allocation doesn't benefit all PMUs. For
instance, ARM SPE and TRBE operate with virtual pages, and Coresight
ETR allocates a separate buffer. For these PMUs, allocating contiguous
AUX pages unnecessarily exacerbates memory fragmentation. This
fragmentation can prevent their use on long-running devices.
This patch modifies the perf driver to be memory-friendly by default,
by allocating non-contiguous AUX pages. For PMUs requiring contiguous
pages (Intel BTS and some Intel PT), the existing
PERF_PMU_CAP_AUX_NO_SG capability can be used. For PMUs that don't
require but can benefit from contiguous pages (some Intel PT), a new
capability, PERF_PMU_CAP_AUX_PREFER_LARGE, is added to maintain their
existing behavior.
Signed-off-by: Yabin Cui <yabinc@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: James Clark <james.clark@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250508232642.148767-1-yabinc@google.com
Affinity-managed interrupts can be shut down and restarted during CPU
hotunplug/plug. Thereby the interrupt may be left in an unexpected state.
Specifically:
1. Interrupt is affine to CPU N
2. disable_irq() -> depth is 1
3. CPU N goes offline
4. irq_shutdown() -> depth is set to 1 (again)
5. CPU N goes online
6. irq_startup() -> depth is set to 0 (BUG! driver expects that the interrupt
still disabled)
7. enable_irq() -> depth underflow / unbalanced enable_irq() warning
This is only a problem for managed interrupts and CPU hotplug, all other
cases like request()/free()/request() truly needs to reset a possibly stale
disable depth value.
Provide a startup function, which takes the disable depth into account, and
invoked it for the managed interrupts in the CPU hotplug path.
This requires to change irq_shutdown() to do a depth increment instead of
setting it to 1, which allows to retain the disable depth, but is harmless
for the other code paths using irq_startup(), which will still reset the
disable depth unconditionally to keep the original correct behaviour.
A kunit tests will be added separately to cover some of these aspects.
[ tglx: Massaged changelog ]
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250514201353.3481400-2-briannorris@chromium.org
Pull Kbuild fixes from Masahiro Yamada:
- Add proper pahole version dependency to CONFIG_GENDWARFKSYMS to avoid
module loading errors
- Fix UAPI header tests for the OpenRISC architecture
- Add dependency on the libdw package in Debian and RPM packages
- Disable -Wdefault-const-init-unsafe warnings on Clang
- Make "make clean ARCH=um" also clean the arch/x86/ directory
- Revert the use of -fmacro-prefix-map=, which causes issues with
debugger usability
* tag 'kbuild-fixes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: fix typos "module.builtin" to "modules.builtin"
Revert "kbuild, rust: use -fremap-path-prefix to make paths relative"
Revert "kbuild: make all file references relative to source root"
kbuild: fix dependency on sorttable
init: remove unused CONFIG_CC_CAN_LINK_STATIC
um: let 'make clean' properly clean underlying SUBARCH as well
kbuild: Disable -Wdefault-const-init-unsafe
kbuild: rpm-pkg: Add (elfutils-devel or libdw-devel) to BuildRequires
kbuild: deb-pkg: Add libdw-dev:native to Build-Depends-Arch
usr/include: openrisc: don't HDRTEST bpf_perf_event.h
kbuild: Require pahole <v1.28 or >v1.29 with GENDWARFKSYMS on X86
Pull tracing fixes from Steven Rostedt:
- Fix sample code that uses trace_array_printk()
The sample code for in kernel use of trace_array (that creates an
instance for use within the kernel) and shows how to use
trace_array_printk() that writes into the created instance, used
trace_printk_init_buffers(). But that function is used to initialize
normal trace_printk() and produces the NOTICE banner which is not
needed for use of trace_array_printk(). The function to initialize
that is trace_array_init_printk() that takes the created trace array
instance as a parameter.
Update the sample code to reflect the proper usage.
- Fix preemption count output for stacktrace event
The tracing buffer shows the preempt count level when an event
executes. Because writing the event itself disables preemption, this
needs to be accounted for when recording. The stacktrace event did
not account for this so the output of the stacktrace event showed
preemption was disabled while the event that triggered the stacktrace
shows preemption is enabled and this leads to confusion. Account for
preemption being disabled for the stacktrace event.
The same happened for stack traces triggered by function tracer.
- Fix persistent ring buffer when trace_pipe is used
The ring buffer swaps the reader page with the next page to read from
the write buffer when trace_pipe is used. If there's only a page of
data in the ring buffer, this swap will cause the "commit" pointer
(last data written) to be on the reader page. If more data is written
to the buffer, it is added to the reader page until it falls off back
into the write buffer.
If the system reboots and the commit pointer is still on the reader
page, even if new data was written, the persistent buffer validator
will miss finding the commit pointer because it only checks the write
buffer and does not check the reader page. This causes the validator
to fail the validation and clear the buffer, where the new data is
lost.
There was a check for this, but it checked the "head pointer", which
was incorrect, because the "head pointer" always stays on the write
buffer and is the next page to swap out for the reader page. Fix the
logic to catch this case and allow the user to still read the data
after reboot.
* tag 'trace-v6.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Fix persistent buffer when commit page is the reader page
ftrace: Fix preemption accounting for stacktrace filter command
ftrace: Fix preemption accounting for stacktrace trigger command
tracing: samples: Initialize trace_array_printk() with the correct function
The ring buffer is made up of sub buffers (sometimes called pages as they
are by default PAGE_SIZE). It has the following "pages":
"tail page" - this is the page that the next write will write to
"head page" - this is the page that the reader will swap the reader page with.
"reader page" - This belongs to the reader, where it will swap the head
page from the ring buffer so that the reader does not
race with the writer.
The writer may end up on the "reader page" if the ring buffer hasn't
written more than one page, where the "tail page" and the "head page" are
the same.
The persistent ring buffer has meta data that points to where these pages
exist so on reboot it can re-create the pointers to the cpu_buffer
descriptor. But when the commit page is on the reader page, the logic is
incorrect.
The check to see if the commit page is on the reader page checked if the
head page was the reader page, which would never happen, as the head page
is always in the ring buffer. The correct check would be to test if the
commit page is on the reader page. If that's the case, then it can exit
out early as the commit page is only on the reader page when there's only
one page of data in the buffer. There's no reason to iterate the ring
buffer pages to find the "commit page" as it is already found.
To trigger this bug:
# echo 1 > /sys/kernel/tracing/instances/boot_mapped/events/syscalls/sys_enter_fchownat/enable
# touch /tmp/x
# chown sshd /tmp/x
# reboot
On boot up, the dmesg will have:
Ring buffer meta [0] is from previous boot!
Ring buffer meta [1] is from previous boot!
Ring buffer meta [2] is from previous boot!
Ring buffer meta [3] is from previous boot!
Ring buffer meta [4] commit page not found
Ring buffer meta [5] is from previous boot!
Ring buffer meta [6] is from previous boot!
Ring buffer meta [7] is from previous boot!
Where the buffer on CPU 4 had a "commit page not found" error and that
buffer is cleared and reset causing the output to be empty and the data lost.
When it works correctly, it has:
# cat /sys/kernel/tracing/instances/boot_mapped/trace_pipe
<...>-1137 [004] ..... 998.205323: sys_enter_fchownat: __syscall_nr=0x104 (260) dfd=0xffffff9c (4294967196) filename=(0xffffc90000a0002c) user=0x3e8 (1000) group=0xffffffff (4294967295) flag=0x0 (0
Cc: stable@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250513115032.3e0b97f7@gandalf.local.home
Fixes: 5f3b6e839f ("ring-buffer: Validate boot range memory events")
Reported-by: Tasos Sahanidis <tasos@tasossah.com>
Tested-by: Tasos Sahanidis <tasos@tasossah.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
