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2025-10-20timekeeping: Fix aux clocks sysfs initialization loop boundHaofeng Li1-1/+1
The loop in tk_aux_sysfs_init() uses `i <= MAX_AUX_CLOCKS` as the termination condition, which results in 9 iterations (i=0 to 8) when MAX_AUX_CLOCKS is defined as 8. However, the kernel is designed to support only up to 8 auxiliary clocks. This off-by-one error causes the creation of a 9th sysfs entry that exceeds the intended auxiliary clock range. Fix the loop bound to use `i < MAX_AUX_CLOCKS` to ensure exactly 8 auxiliary clock entries are created, matching the design specification. Fixes: 7b95663a3d96 ("timekeeping: Provide interface to control auxiliary clocks") Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/tencent_2376993D9FC06A3616A4F981B3DE1C599607@qq.com
2025-10-02Merge tag 'net-next-6.18' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "Core & protocols: - Improve drop account scalability on NUMA hosts for RAW and UDP sockets and the backlog, almost doubling the Pps capacity under DoS - Optimize the UDP RX performance under stress, reducing contention, revisiting the binary layout of the involved data structs and implementing NUMA-aware locking. This improves UDP RX performance by an additional 50%, even more under extreme conditions - Add support for PSP encryption of TCP connections; this mechanism has some similarities with IPsec and TLS, but offers superior HW offloads capabilities - Ongoing work to support Accurate ECN for TCP. AccECN allows more than one congestion notification signal per RTT and is a building block for Low Latency, Low Loss, and Scalable Throughput (L4S) - Reorganize the TCP socket binary layout for data locality, reducing the number of touched cachelines in the fastpath - Refactor skb deferral free to better scale on large multi-NUMA hosts, this improves TCP and UDP RX performances significantly on such HW - Increase the default socket memory buffer limits from 256K to 4M to better fit modern link speeds - Improve handling of setups with a large number of nexthop, making dump operating scaling linearly and avoiding unneeded synchronize_rcu() on delete - Improve bridge handling of VLAN FDB, storing a single entry per bridge instead of one entry per port; this makes the dump order of magnitude faster on large switches - Restore IP ID correctly for encapsulated packets at GSO segmentation time, allowing GRO to merge packets in more scenarios - Improve netfilter matching performance on large sets - Improve MPTCP receive path performance by leveraging recently introduced core infrastructure (skb deferral free) and adopting recent TCP autotuning changes - Allow bridges to redirect to a backup port when the bridge port is administratively down - Introduce MPTCP 'laminar' endpoint that con be used only once per connection and simplify common MPTCP setups - Add RCU safety to dst->dev, closing a lot of possible races - A significant crypto library API for SCTP, MPTCP and IPv6 SR, reducing code duplication - Supports pulling data from an skb frag into the linear area of an XDP buffer Things we sprinkled into general kernel code: - Generate netlink documentation from YAML using an integrated YAML parser Driver API: - Support using IPv6 Flow Label in Rx hash computation and RSS queue selection - Introduce API for fetching the DMA device for a given queue, allowing TCP zerocopy RX on more H/W setups - Make XDP helpers compatible with unreadable memory, allowing more easily building DevMem-enabled drivers with a unified XDP/skbs datapath - Add a new dedicated ethtool callback enabling drivers to provide the number of RX rings directly, improving efficiency and clarity in RX ring queries and RSS configuration - Introduce a burst period for the health reporter, allowing better handling of multiple errors due to the same root cause - Support for DPLL phase offset exponential moving average, controlling the average smoothing factor Device drivers: - Add a new Huawei driver for 3rd gen NIC (hinic3) - Add a new SpacemiT driver for K1 ethernet MAC - Add a generic abstraction for shared memory communication devices (dibps) - Ethernet high-speed NICs: - nVidia/Mellanox: - Use multiple per-queue doorbell, to avoid MMIO contention issues - support adjacent functions, allowing them to delegate their SR-IOV VFs to sibling PFs - support RSS for IPSec offload - support exposing raw cycle counters in PTP and mlx5 - support for disabling host PFs. - Intel (100G, ice, idpf): - ice: support for SRIOV VFs over an Active-Active link aggregate - ice: support for firmware logging via debugfs - ice: support for Earliest TxTime First (ETF) hardware offload - idpf: support basic XDP functionalities and XSk - Broadcom (bnxt): - support Hyper-V VF ID - dynamic SRIOV resource allocations for RoCE - Meta (fbnic): - support queue API, zero-copy Rx and Tx - support basic XDP functionalities - devlink health support for FW crashes and OTP mem corruptions - expand hardware stats coverage to FEC, PHY, and Pause - Wangxun: - support ethtool coalesce options - support for multiple RSS contexts - Ethernet virtual: - Macsec: - replace custom netlink attribute checks with policy-level checks - Bonding: - support aggregator selection based on port priority - Microsoft vNIC: - use page pool fragments for RX buffers instead of full pages to improve memory efficiency - Ethernet NICs consumer, and embedded: - Qualcomm: support Ethernet function for IPQ9574 SoC - Airoha: implement wlan offloading via NPU - Freescale - enetc: add NETC timer PTP driver and add PTP support - fec: enable the Jumbo frame support for i.MX8QM - Renesas (R-Car S4): - support HW offloading for layer 2 switching - support for RZ/{T2H, N2H} SoCs - Cadence (macb): support TAPRIO traffic scheduling - TI: - support for Gigabit ICSS ethernet SoC (icssm-prueth) - Synopsys (stmmac): a lot of cleanups - Ethernet PHYs: - Support 10g-qxgmi phy-mode for AQR412C, Felix DSA and Lynx PCS driver - Support bcm63268 GPHY power control - Support for Micrel lan8842 PHY and PTP - Support for Aquantia AQR412 and AQR115 - CAN: - a large CAN-XL preparation work - reorganize raw_sock and uniqframe struct to minimize memory usage - rcar_canfd: update the CAN-FD handling - WiFi: - extended Neighbor Awareness Networking (NAN) support - S1G channel representation cleanup - improve S1G support - WiFi drivers: - Intel (iwlwifi): - major refactor and cleanup - Broadcom (brcm80211): - support for AP isolation - RealTek (rtw88/89) rtw88/89: - preparation work for RTL8922DE support - MediaTek (mt76): - HW restart improvements - MLO support - Qualcomm/Atheros (ath10k): - GTK rekey fixes - Bluetooth drivers: - btusb: support for several new IDs for MT7925 - btintel: support for BlazarIW core - btintel_pcie: support for _suspend() / _resume() - btintel_pcie: support for Scorpious, Panther Lake-H484 IDs" * tag 'net-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1536 commits) net: stmmac: Add support for Allwinner A523 GMAC200 dt-bindings: net: sun8i-emac: Add A523 GMAC200 compatible Revert "Documentation: net: add flow control guide and document ethtool API" octeontx2-pf: fix bitmap leak octeontx2-vf: fix bitmap leak net/mlx5e: Use extack in set rxfh callback net/mlx5e: Introduce mlx5e_rss_params for RSS configuration net/mlx5e: Introduce mlx5e_rss_init_params net/mlx5e: Remove unused mdev param from RSS indir init net/mlx5: Improve QoS error messages with actual depth values net/mlx5e: Prevent entering switchdev mode with inconsistent netns net/mlx5: HWS, Generalize complex matchers net/mlx5: Improve write-combining test reliability for ARM64 Grace CPUs selftests/net: add tcp_port_share to .gitignore Revert "net/mlx5e: Update and set Xon/Xoff upon MTU set" net: add NUMA awareness to skb_attempt_defer_free() net: use llist for sd->defer_list net: make softnet_data.defer_count an atomic selftests: drv-net: psp: add tests for destroying devices selftests: drv-net: psp: add test for auto-adjusting TCP MSS ...
2025-09-30Merge tag 'timers-vdso-2025-09-29' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull VDSO updates from Thomas Gleixner: - Further consolidation of the VDSO infrastructure and the common data store - Simplification of the related Kconfig logic - Improve the VDSO selftest suite * tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests: vDSO: Drop vdso_test_clock_getres selftests: vDSO: vdso_test_abi: Add tests for clock_gettime64() selftests: vDSO: vdso_test_abi: Test CPUTIME clocks selftests: vDSO: vdso_test_abi: Use explicit indices for name array selftests: vDSO: vdso_test_abi: Drop clock availability tests selftests: vDSO: vdso_test_abi: Use ksft_finished() selftests: vDSO: vdso_test_abi: Correctly skip whole test with missing vDSO selftests: vDSO: Fix -Wunitialized in powerpc VDSO_CALL() wrapper vdso: Add struct __kernel_old_timeval forward declaration to gettime.h vdso: Gate VDSO_GETRANDOM behind HAVE_GENERIC_VDSO vdso: Drop Kconfig GENERIC_VDSO_TIME_NS vdso: Drop Kconfig GENERIC_VDSO_DATA_STORE vdso: Drop kconfig GENERIC_COMPAT_VDSO vdso: Drop kconfig GENERIC_VDSO_32 riscv: vdso: Untangle Kconfig logic time: Build generic update_vsyscall() only with generic time vDSO vdso/gettimeofday: Remove !CONFIG_TIME_NS stubs vdso: Move ENABLE_COMPAT_VDSO from core to arm64 ARM: VDSO: Remove cntvct_ok global variable vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY
2025-09-30Merge tag 'timers-clocksource-2025-09-29' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull clocksource updates from Thomas Gleixner: - Further preparations for modular clocksource/event drivers - The usual device tree updates to support new chip variants and the related changes to thise drivers - Avoid a 64-bit division in the TEGRA186 driver, which caused a build fail on 32-bit machines. - Small fixes, improvements and cleanups all over the place * tag 'timers-clocksource-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) dt-bindings: timer: exynos4210-mct: Add compatible for ARTPEC-9 SoC clocksource/drivers/sh_cmt: Split start/stop of clock source and events clocksource/drivers/clps711x: Fix resource leaks in error paths clocksource/drivers/arm_global_timer: Add auto-detection for initial prescaler values clocksource/drivers/ingenic-sysost: Convert from round_rate() to determine_rate() clocksource/drivers/timer-tegra186: Don't print superfluous errors clocksource/drivers/timer-rtl-otto: Simplify documentation clocksource/drivers/timer-rtl-otto: Do not interfere with interrupts clocksource/drivers/timer-rtl-otto: Drop set_counter function clocksource/drivers/timer-rtl-otto: Work around dying timers clocksource/drivers/timer-ti-dm : Capture functionality for OMAP DM timer clocksource/drivers/arm_arch_timer_mmio: Add MMIO clocksource clocksource/drivers/arm_arch_timer_mmio: Switch over to standalone driver clocksource/drivers/arm_arch_timer: Add standalone MMIO driver ACPI: GTDT: Generate platform devices for MMIO timers clocksource/drivers/nxp-pit: Add NXP Automotive s32g2 / s32g3 support dt: bindings: fsl,vf610-pit: Add compatible for s32g2 and s32g3 clocksource/drivers/vf-pit: Rename the VF PIT to NXP PIT clocksource/drivers/vf-pit: Unify the function name for irq ack clocksource/drivers/vf-pit: Consolidate calls to pit_*_disable/enable ...
2025-09-30Merge tag 'timers-core-2025-09-29' of ↵Linus Torvalds9-38/+43
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner: - Address the inconsistent shutdown sequence of per CPU clockevents on CPU hotplug, which only removed it from the core but failed to invoke the actual device driver shutdown callback. This kept the timer active, which prevented power savings and caused pointless noise in virtualization. - Encapsulate the open coded access to the hrtimer clock base, which is a private implementation detail, so that the implementation can be changed without breaking a lot of usage sites. - Enhance the debug output of the clocksource watchdog to provide better information for analysis. - The usual set of cleanups and enhancements all over the place * tag 'timers-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time: Fix spelling mistakes in comments clocksource: Print durations for sync check unconditionally LoongArch: Remove clockevents shutdown call on offlining tick: Do not set device to detached state in tick_shutdown() hrtimer: Reorder branches in hrtimer_clockid_to_base() hrtimer: Remove hrtimer_clock_base:: Get_time hrtimer: Use hrtimer_cb_get_time() helper media: pwm-ir-tx: Avoid direct access to hrtimer clockbase ALSA: hrtimer: Avoid direct access to hrtimer clockbase lib: test_objpool: Avoid direct access to hrtimer clockbase sched/core: Avoid direct access to hrtimer clockbase timers/itimer: Avoid direct access to hrtimer clockbase posix-timers: Avoid direct access to hrtimer clockbase jiffies: Remove obsolete SHIFTED_HZ comment
2025-09-29Merge tag 'namespace-6.18-rc1' of ↵Linus Torvalds1-16/+16
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull namespace updates from Christian Brauner: "This contains a larger set of changes around the generic namespace infrastructure of the kernel. Each specific namespace type (net, cgroup, mnt, ...) embedds a struct ns_common which carries the reference count of the namespace and so on. We open-coded and cargo-culted so many quirks for each namespace type that it just wasn't scalable anymore. So given there's a bunch of new changes coming in that area I've started cleaning all of this up. The core change is to make it possible to correctly initialize every namespace uniformly and derive the correct initialization settings from the type of the namespace such as namespace operations, namespace type and so on. This leaves the new ns_common_init() function with a single parameter which is the specific namespace type which derives the correct parameters statically. This also means the compiler will yell as soon as someone does something remotely fishy. The ns_common_init() addition also allows us to remove ns_alloc_inum() and drops any special-casing of the initial network namespace in the network namespace initialization code that Linus complained about. Another part is reworking the reference counting. The reference counting was open-coded and copy-pasted for each namespace type even though they all followed the same rules. This also removes all open accesses to the reference count and makes it private and only uses a very small set of dedicated helpers to manipulate them just like we do for e.g., files. In addition this generalizes the mount namespace iteration infrastructure introduced a few cycles ago. As reminder, the vfs makes it possible to iterate sequentially and bidirectionally through all mount namespaces on the system or all mount namespaces that the caller holds privilege over. This allow userspace to iterate over all mounts in all mount namespaces using the listmount() and statmount() system call. Each mount namespace has a unique identifier for the lifetime of the systems that is exposed to userspace. The network namespace also has a unique identifier working exactly the same way. This extends the concept to all other namespace types. The new nstree type makes it possible to lookup namespaces purely by their identifier and to walk the namespace list sequentially and bidirectionally for all namespace types, allowing userspace to iterate through all namespaces. Looking up namespaces in the namespace tree works completely locklessly. This also means we can move the mount namespace onto the generic infrastructure and remove a bunch of code and members from struct mnt_namespace itself. There's a bunch of stuff coming on top of this in the future but for now this uses the generic namespace tree to extend a concept introduced first for pidfs a few cycles ago. For a while now we have supported pidfs file handles for pidfds. This has proven to be very useful. This extends the concept to cover namespaces as well. It is possible to encode and decode namespace file handles using the common name_to_handle_at() and open_by_handle_at() apis. As with pidfs file handles, namespace file handles are exhaustive, meaning it is not required to actually hold a reference to nsfs in able to decode aka open_by_handle_at() a namespace file handle. Instead the FD_NSFS_ROOT constant can be passed which will let the kernel grab a reference to the root of nsfs internally and thus decode the file handle. Namespaces file descriptors can already be derived from pidfds which means they aren't subject to overmount protection bugs. IOW, it's irrelevant if the caller would not have access to an appropriate /proc/<pid>/ns/ directory as they could always just derive the namespace based on a pidfd already. It has the same advantage as pidfds. It's possible to reliably and for the lifetime of the system refer to a namespace without pinning any resources and to compare them trivially. Permission checking is kept simple. If the caller is located in the namespace the file handle refers to they are able to open it otherwise they must hold privilege over the owning namespace of the relevant namespace. The namespace file handle layout is exposed as uapi and has a stable and extensible format. For now it simply contains the namespace identifier, the namespace type, and the inode number. The stable format means that userspace may construct its own namespace file handles without going through name_to_handle_at() as they are already allowed for pidfs and cgroup file handles" * tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (65 commits) ns: drop assert ns: move ns type into struct ns_common nstree: make struct ns_tree private ns: add ns_debug() ns: simplify ns_common_init() further cgroup: add missing ns_common include ns: use inode initializer for initial namespaces selftests/namespaces: verify initial namespace inode numbers ns: rename to __ns_ref nsfs: port to ns_ref_*() helpers net: port to ns_ref_*() helpers uts: port to ns_ref_*() helpers ipv4: use check_net() net: use check_net() net-sysfs: use check_net() user: port to ns_ref_*() helpers time: port to ns_ref_*() helpers pid: port to ns_ref_*() helpers ipc: port to ns_ref_*() helpers cgroup: port to ns_ref_*() helpers ...
2025-09-29Merge tag 'kernel-6.18-rc1.clone3' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull copy_process updates from Christian Brauner: "This contains the changes to enable support for clone3() on nios2 which apparently is still a thing. The more exciting part of this is that it cleans up the inconsistency in how the 64-bit flag argument is passed from copy_process() into the various other copy_*() helpers" [ Fixed up rv ltl_monitor 32-bit support as per Sasha Levin in the merge ] * tag 'kernel-6.18-rc1.clone3' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: nios2: implement architecture-specific portion of sys_clone3 arch: copy_thread: pass clone_flags as u64 copy_process: pass clone_flags as u64 across calltree copy_sighand: Handle architectures where sizeof(unsigned long) < sizeof(u64)
2025-09-25ns: move ns type into struct ns_commonChristian Brauner1-2/+1
It's misplaced in struct proc_ns_operations and ns->ops might be NULL if the namespace is compiled out but we still want to know the type of the namespace for the initial namespace struct. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-23time/sched_clock: Export symbol for sched_clock register functionDaniel Lezcano1-2/+2
The timer drivers could be converted into modules. The different functions to register the clocksource or the clockevent are already exporting their symbols for modules but the sched_clock_register() function is missing. Export the symbols so the drivers using this function can be converted into modules. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Carlos Llamas <cmllamas@google.com> Reviewed-by: Will McVicker <willmcvicker@google.com> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/r/20250602151853.1942521-8-daniel.lezcano@linaro.org
2025-09-22ns: simplify ns_common_init() furtherChristian Brauner1-1/+1
Simply derive the ns operations from the namespace type. Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-21time: Fix spelling mistakes in commentsHaofeng Li4-4/+4
Correct several typos found in comments across various files in the kernel/time directory. No functional changes are introduced by these corrections. Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2025-09-19ns: use inode initializer for initial namespacesChristian Brauner1-1/+1
Just use the common helper we have. Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19ns: rename to __ns_refChristian Brauner1-1/+1
Make it easier to grep and rename to ns_count. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19ns: add ns_common_free()Christian Brauner1-1/+1
And drop ns_free_inum(). Anything common that can be wasted centrally should be wasted in the new common helper. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19nscommon: simplify initializationChristian Brauner1-1/+1
There's a lot of information that namespace implementers don't need to know about at all. Encapsulate this all in the initialization helper. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19ns: add to_<type>_ns() to respective headersChristian Brauner1-5/+0
Every namespace type has a container_of(ns, <ns_type>, ns) static inline function that is currently not exposed in the header. So we have a bunch of places that open-code it via container_of(). Move it to the headers so we can use it directly. Reviewed-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19time: support ns lookupChristian Brauner1-1/+10
Support the generic ns lookup infrastructure to support file handles for namespaces. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19time: use ns_common_init()Christian Brauner1-5/+2
Don't cargo-cult the same thing over and over. Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-8/+3
Cross-merge networking fixes after downstream PR (net-6.17-rc7). No conflicts. Adjacent changes: drivers/net/ethernet/mellanox/mlx5/core/en/fs.h 9536fbe10c9d ("net/mlx5e: Add PSP steering in local NIC RX") 7601a0a46216 ("net/mlx5e: Add a miss level for ipsec crypto offload") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-4/+10
Cross-merge networking fixes after downstream PR (net-6.17-rc6). Conflicts: net/netfilter/nft_set_pipapo.c net/netfilter/nft_set_pipapo_avx2.c c4eaca2e1052 ("netfilter: nft_set_pipapo: don't check genbit from packetpath lookups") 84c1da7b38d9 ("netfilter: nft_set_pipapo: use avx2 algorithm for insertions too") Only trivial adjacent changes (in a doc and a Makefile). Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-09clocksource: Print durations for sync check unconditionallyJiri Wiesner1-3/+2
A typical set of messages that gets printed as a result of the clocksource watchdog finding the TSC unstable usually does not contain messages indicating CPUs being ahead of or behind the CPU from which the check is carried out. That fact suggests that the TSC does not experience time skew between CPUs (if the clocksource.verify_n_cpus parameter is set to a negative value) but quantitative information is missing. The cs_nsec_max value printed by the "CPU %d check durations" message actually provides a worst case estimate of the time skew. If all CPUs have been checked, the cs_nsec_max value multiplied by 2 is the maximum possible time skew between the TSCs of any two CPUs on the system. The worst case estimate is derived from two boundary cases: 1. No time is consumed to execute instructions between csnow_begin and csnow_mid while all the cs_nsec_max time is consumed by the code between csnow_mid and csnow_end. In this case, the maximum undetectable time skew of a CPU being ahead would be cs_nsec_max. 2. All the cs_nsec_max time is consumed to execute instructions between csnow_begin and csnow_mid while no time is consumed by the code between csnow_mid and csnow_end. In this case, the maximum undetectable time skew of a CPU being behind would be cs_nsec_max. The worst case estimate assumes a system experiencing a corner case consisting of the two boundary cases. Always print the "CPU %d check durations" message so that the maximum possible time skew measured by the TSC sync check can be compared to the time skew measured by the clocksource watchdog. Signed-off-by: Jiri Wiesner <jwiesner@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/all/aIuXXfdITXdI0lLp@incl
2025-09-09hrtimers: Unconditionally update target CPU base after offline timer migrationXiongfeng Wang1-8/+3
When testing softirq based hrtimers on an ARM32 board, with high resolution mode and NOHZ inactive, softirq based hrtimers fail to expire after being moved away from an offline CPU: CPU0 CPU1 hrtimer_start(..., HRTIMER_MODE_SOFT); cpu_down(CPU1) ... hrtimers_cpu_dying() // Migrate timers to CPU0 smp_call_function_single(CPU0, returgger_next_event); retrigger_next_event() if (!highres && !nohz) return; As retrigger_next_event() is a NOOP when both high resolution timers and NOHZ are inactive CPU0's hrtimer_cpu_base::softirq_expires_next is not updated and the migrated softirq timers never expire unless there is a softirq based hrtimer queued on CPU0 later. Fix this by removing the hrtimer_hres_active() and tick_nohz_active() check in retrigger_next_event(), which enforces a full update of the CPU base. As this is not a fast path the extra cost does not matter. [ tglx: Massaged change log ] Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier") Co-developed-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250805081025.54235-1-wangxiongfeng2@huawei.com
2025-09-09tick: Do not set device to detached state in tick_shutdown()Bibo Mao3-13/+7
tick_shutdown() sets the state of the clockevent device to detached first and the invokes clockevents_exchange_device(), which in turn invokes clockevents_switch_state(). But clockevents_switch_state() returns without invoking the device shutdown callback as the device is already in detached state. As a consequence the timer device is not shutdown when a CPU goes offline. tick_shutdown() does this because it was originally invoked on a online CPU and not on the outgoing CPU. It therefore could not access the clockevent device of the already offlined CPU and just set the state. Since commit 3b1596a21fbf tick_shutdown() is called on the outgoing CPU, so the hardware device can be accessed. Remove the state set before calling clockevents_exchange_device(), so that the subsequent clockevents_switch_state() handles the state transition and invokes the shutdown callback of the clockevent device. [ tglx: Massaged change log ] Fixes: 3b1596a21fbf ("clockevents: Shutdown and unregister current clockevents at CPUHP_AP_TICK_DYING") Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/all/20250906064952.3749122-2-maobibo@loongson.cn
2025-09-09hrtimer: Reorder branches in hrtimer_clockid_to_base()Thomas Weißschuh1-2/+2
Align the ordering to the one used for hrtimer_bases. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250821-hrtimer-cleanup-get_time-v2-9-3ae822e5bfbd@linutronix.de
2025-09-09hrtimer: Remove hrtimer_clock_base:: Get_timeThomas Weißschuh2-11/+25
The get_time() callbacks always need to match the bases clockid. Instead of maintaining that association twice in hrtimer_bases, use a helper. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250821-hrtimer-cleanup-get_time-v2-8-3ae822e5bfbd@linutronix.de
2025-09-09timers/itimer: Avoid direct access to hrtimer clockbaseThomas Weißschuh1-2/+1
The field timer->base->get_time is a private implementation detail and should not be accessed outside of the hrtimer core. Switch to the equivalent helper. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250821-hrtimer-cleanup-get_time-v2-2-3ae822e5bfbd@linutronix.de
2025-09-09posix-timers: Avoid direct access to hrtimer clockbaseThomas Weißschuh1-3/+2
The field timer->base->get_time is a private implementation detail and should not be accessed outside of the hrtimer core. Switch to the equivalent helpers. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250821-hrtimer-cleanup-get_time-v2-1-3ae822e5bfbd@linutronix.de
2025-09-04time: Build generic update_vsyscall() only with generic time vDSOThomas Weißschuh1-1/+1
The generic vDSO can be used without the time-related functionality. In that case the generic update_vsyscall() from kernel/time/vsyscall.c should not be built. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-5-d9b65750e49f@linutronix.de
2025-09-03time: export timespec64_add_safe() symbolGatien Chevallier1-0/+1
Export the timespec64_add_safe() symbol so that this function can be used in modules where computation of time related is done. Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20250901-relative_flex_pps-v4-1-b874971dfe85@foss.st.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-03vdso/vsyscall: Avoid slow division loop in auxiliary clock updateThomas Weißschuh2-4/+10
The call to __iter_div_u64_rem() in vdso_time_update_aux() is a wrapper around subtraction. It cannot be used to divide large numbers, as that introduces long, computationally expensive delays. A regular u64 division is also not possible in the timekeeper update path as it can be too slow. Instead of splitting the ktime_t offset into into second and subsecond components during the timekeeper update fast-path, do it together with the adjustment of tk->offs_aux in the slow-path. Equivalent to the handling of offs_boot and monotonic_to_boot. Reuse the storage of monotonic_to_boot for the new field, as it is not used by auxiliary timekeepers. Fixes: 380b84e168e5 ("vdso/vsyscall: Update auxiliary clock data in the datapage") Reported-by: Miroslav Lichvar <mlichvar@redhat.com> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250825-vdso-auxclock-division-v1-1-a1d32a16a313@linutronix.de Closes: https://lore.kernel.org/lkml/aKwsNNWsHJg8IKzj@localhost/
2025-09-01copy_process: pass clone_flags as u64 across calltreeSimon Schuster1-1/+1
With the introduction of clone3 in commit 7f192e3cd316 ("fork: add clone3") the effective bit width of clone_flags on all architectures was increased from 32-bit to 64-bit, with a new type of u64 for the flags. However, for most consumers of clone_flags the interface was not changed from the previous type of unsigned long. While this works fine as long as none of the new 64-bit flag bits (CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still undesirable in terms of the principle of least surprise. Thus, this commit fixes all relevant interfaces of callees to sys_clone3/copy_process (excluding the architecture-specific copy_thread) to consistently pass clone_flags as u64, so that no truncation to 32-bit integers occurs on 32-bit architectures. Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com> Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-2-53fcf5577d57@siemens-energy.com Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-31Merge tag 'bitmap-for-6.17' of https://github.com/norov/linuxLinus Torvalds1-4/+1
Pull bitmap updates from Yury Norov: - find_random_bit() series (Yury) - GENMASK() consolidation (Vincent) - random cleanups (Shaopeng, Ben, Yury) * tag 'bitmap-for-6.17' of https://github.com/norov/linux: bitfield: Ensure the return values of helper functions are checked test_bits: add tests for __GENMASK() and __GENMASK_ULL() bits: unify the non-asm GENMASK*() bits: split the definition of the asm and non-asm GENMASK*() cpumask: Remove unnecessary cpumask_nth_andnot() watchdog: fix opencoded cpumask_next_wrap() in watchdog_next_cpu() clocksource: Improve randomness in clocksource_verify_choose_cpus() cpumask: introduce cpumask_random() bitmap: generalize node_random()
2025-07-31clocksource: Improve randomness in clocksource_verify_choose_cpus()Yury Norov [NVIDIA]1-4/+1
The current algorithm of picking a random CPU works OK for dense online cpumask, but if cpumask is non-dense, the distribution of picked CPUs is skewed. For example, on 8-CPU board with CPUs 4-7 offlined, the probability of selecting CPU 0 is 5/8. Accordingly, cpus 1, 2 and 3 are chosen with probability 1/8 each. The proper algorithm should pick each online CPU with probability 1/4. Switch it to cpumask_random(), which has better statistical characteristics. CC: Andrew Morton <akpm@linux-foundation.org> Acked-by: John Stultz <jstultz@google.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Yury Norov [NVIDIA]" <yury.norov@gmail.com>
2025-07-29Merge tag 'timers-ptp-2025-07-27' of ↵Linus Torvalds9-131/+680
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timekeeping and VDSO updates from Thomas Gleixner: - Introduce support for auxiliary timekeepers PTP clocks can be disconnected from the universal CLOCK_TAI reality for various reasons including regularatory requirements for functional safety redundancy. The kernel so far only supports a single notion of time, which means that all clocks are correlated in frequency and only differ by offset to each other. Access to non-correlated PTP clocks has been available so far only through the file descriptor based "POSIX clock IDs", which are subject to locking and have to go all the way out to the hardware. The access is not only horribly slow, as it has to go all the way out to the NIC/PTP hardware, but that also prevents the kernel to read the time of such clocks e.g. from the network stack, where it is required for TSN networking both on the transmit and receive side unless the hardware provides offloading. The auxiliary clocks provide a mechanism to support arbitrary clocks which are not correlated to the system clock. This is not restricted to the PTP use case on purpose as there is no kernel side association of these clocks to a particular PTP device because that's a pure user space configuration decision. Having them independent allows to utilize them for other purposes and also enables them to be tested without hardware dependencies. To avoid pointless overhead these clocks have to be enabled individualy via a new sysfs interface to reduce the overhead to a single compare in the hotpath if they are enabled at the Kconfig level at all. These clocks utilize the existing timekeeping/NTP infrastructures, which has been made possible over the recent releases by incrementaly converting these infrastructures over from a single static instance to a multi-instance pointer based implementation without any performance regression reported. The auxiliary clocks provide the same "emulation" of a "correct" clock as the existing CLOCK_* variants do with an independent instance of data and provide the same steering mechanism through the existing sys_clock_adjtime() interface, which has been confirmed to work by the chronyd(8) maintainer. That allows to provide lockless kernel internal and VDSO support so that applications and kernel internal functionalities can access these clocks without restrictions and at the same performance as the existing system clocks. - Avoid double notifications in the adjtimex() syscall. Not a big issue, but a trivial to avoid latency source. * tag 'timers-ptp-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) vdso/gettimeofday: Add support for auxiliary clocks vdso/vsyscall: Update auxiliary clock data in the datapage vdso: Introduce aux_clock_resolution_ns() vdso/gettimeofday: Introduce vdso_get_timestamp() vdso/gettimeofday: Introduce vdso_set_timespec() vdso/gettimeofday: Introduce vdso_clockid_valid() vdso/gettimeofday: Return bool from clock_gettime() helpers vdso/gettimeofday: Return bool from clock_getres() helpers vdso/helpers: Add helpers for seqlocks of single vdso_clock vdso/vsyscall: Split up __arch_update_vsyscall() into __arch_update_vdso_clock() vdso/vsyscall: Introduce a helper to fill clock configurations timekeeping: Remove the temporary CLOCK_AUX workaround timekeeping: Provide ktime_get_clock_ts64() timekeeping: Provide interface to control auxiliary clocks timekeeping: Provide update for auxiliary timekeepers timekeeping: Provide adjtimex() for auxiliary clocks timekeeping: Prepare do_adtimex() for auxiliary clocks timekeeping: Make do_adjtimex() reusable timekeeping: Add auxiliary clock support to __timekeeping_inject_offset() timekeeping: Make timekeeping_inject_offset() reusable ...
2025-07-29Merge tag 'timers-core-2025-07-27' of ↵Linus Torvalds2-19/+12
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner: - Simplify the logic in the timer migration code - Simplify the clocksource code by utilizing the more modern cpumask+*() interfaces * tag 'timers-core-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: Use cpumask_next_wrap() in clocksource_watchdog() clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus() timers/migration: Clean up the loop in tmigr_quick_check()
2025-07-29Merge tag 'timers-cleanups-2025-07-27' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer cleanups from Thomas Gleixner: "A treewide cleanup of struct cycle_counter const annotations. The initial idea of making them const was correct as they were seperate instances. When they got embedded into larger data structures, which are even modified by the callback this got moot. The only reason why this went unnoticed is that the required container_of() casts the const attribute forcefully away. Stop pretending that it is const" * tag 'timers-cleanups-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time/timecounter: Fix the lie that struct cyclecounter is const
2025-07-22timekeeping: Zero initialize system_counterval when querying time from phc ↵Markus Blöchl1-1/+1
drivers Most drivers only populate the fields cycles and cs_id of system_counterval in their get_time_fn() callback for get_device_system_crosststamp(), unless they explicitly provide nanosecond values. When the use_nsecs field was added to struct system_counterval, most drivers did not care. Clock sources other than CSID_GENERIC could then get converted in convert_base_to_cs() based on an uninitialized use_nsecs field, which usually results in -EINVAL during the following range check. Pass in a fully zero initialized system_counterval_t to cure that. Fixes: 6b2e29977518 ("timekeeping: Provide infrastructure for converting to/from a base clock") Signed-off-by: Markus Blöchl <markus@blochl.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20250720-timekeeping_uninit_crossts-v2-1-f513c885b7c2@blochl.de
2025-07-18vdso/vsyscall: Update auxiliary clock data in the datapageThomas Weißschuh3-0/+57
Expose the auxiliary clock data so it can be read from the vDSO. Architectures not using the generic vDSO time framework, namely SPARC64, are not supported. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-11-df7d9f87b9b8@linutronix.de
2025-07-18vdso: Introduce aux_clock_resolution_ns()Thomas Weißschuh1-2/+4
Move the constant resolution to a shared header, so the vDSO can use it and return it without going through a syscall. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-10-df7d9f87b9b8@linutronix.de
2025-07-09vdso/vsyscall: Split up __arch_update_vsyscall() into __arch_update_vdso_clock()Thomas Weißschuh1-1/+2
The upcoming auxiliary clocks need this hook, too. To separate the architecture hooks from the timekeeper internals, refactor the hook to only operate on a single vDSO clock. While at it, use a more robust #define for the hook override. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-3-df7d9f87b9b8@linutronix.de
2025-07-09vdso/vsyscall: Introduce a helper to fill clock configurationsThomas Weißschuh1-14/+13
The logic to configure a 'struct vdso_clock' from a 'struct tk_read_base' is copied two times. Split it into a shared function to reduce the duplication, especially as another user will be added for auxiliary clocks. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-2-df7d9f87b9b8@linutronix.de
2025-07-09Merge v6.16-rc2 into timers/ptpThomas Gleixner1-0/+9
to pick up the __GENMASK() fix, otherwise the AUX clock VDSO patches fail to compile for compat. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2025-07-03Merge tag 'ktime-get-clock-ts64-for-ptp' into timers/ptpThomas Gleixner1-0/+34
Pull the base implementation of ktime_get_clock_ts64() for PTP, which contains a temporary CLOCK_AUX* workaround. That was created to allow integration of depending changes into the networking tree. The workaround is going to be removed in a subsequent change in the timekeeping tree. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2025-07-03timekeeping: Provide ktime_get_clock_ts64()Thomas Gleixner1-0/+33
PTP implements an inline switch case for taking timestamps from various POSIX clock IDs, which already consumes quite some text space. Expanding it for auxiliary clocks really becomes too big for inlining. Provide a out of line version. The function invalidates the timestamp in case the clock is invalid. The invalidation allows to implement a validation check without the need to propagate a return value through deep existing call chains. Due to merge logistics this temporarily defines CLOCK_AUX[_LAST] if undefined, so that the plain branch, which does not contain any of the core timekeeper changes, can be pulled into the networking tree as prerequisite for the PTP side changes. These temporary defines are removed after that branch is merged into the tip::timers/ptp branch. That way the result in -next or upstream in the next merge window has zero dependencies. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250701132628.357686408@linutronix.de
2025-07-01time/timecounter: Fix the lie that struct cyclecounter is constGreg Kroah-Hartman1-1/+1
In both the read callback for struct cyclecounter, and in struct timecounter, struct cyclecounter is declared as a const pointer. Unfortunatly, a number of users of this pointer treat it as a non-const pointer as it is burried in a larger structure that is heavily modified by the callback function when accessed. This lie had been hidden by the fact that container_of() "casts away" a const attribute of a pointer without any compiler warning happening at all. Fix this all up by removing the const attribute in the needed places so that everyone can see that the structure really isn't const, but can, and is, modified by the users of it. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/2025070124-backyard-hurt-783a@gregkh
2025-06-27timekeeping: Provide interface to control auxiliary clocksThomas Gleixner1-0/+116
Auxiliary clocks are disabled by default and attempts to access them fail. Provide an interface to enable/disable them at run-time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.444626478@linutronix.de
2025-06-27timekeeping: Provide update for auxiliary timekeepersThomas Gleixner1-0/+19
Update the auxiliary timekeepers periodically. For now this is tied to the system timekeeper update from the tick. This might be revisited and moved out of the tick. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.382451331@linutronix.de
2025-06-27timekeeping: Provide adjtimex() for auxiliary clocksThomas Gleixner1-0/+16
The behaviour is close to clock_adtime(CLOCK_REALTIME) with the following differences: 1) ADJ_SETOFFSET adjusts the auxiliary clock offset 2) ADJ_TAI is not supported 3) Leap seconds are not supported 4) PPS is not supported Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.317946543@linutronix.de
2025-06-27timekeeping: Prepare do_adtimex() for auxiliary clocksThomas Gleixner1-3/+33
Exclude ADJ_TAI, leap seconds and PPS functionality as they make no sense in the context of auxiliary clocks and provide a time stamp based on the actual clock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.253203783@linutronix.de
2025-06-27timekeeping: Make do_adjtimex() reusableThomas Gleixner1-46/+56
Split out the actual functionality of adjtimex() and make do_adjtimex() a wrapper which feeds the core timekeeper into it and handles the result including audit at the call site. This allows to reuse the actual functionality for auxiliary clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.187322876@linutronix.de