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2024-03-13Merge tag 'pm-6.9-rc1' of ↵Linus Torvalds2-2/+73
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "From the functional perspective, the most significant change here is the addition of support for Energy Models that can be updated dynamically at run time. There is also the addition of LZ4 compression support for hibernation, the new preferred core support in amd-pstate, new platforms support in the Intel RAPL driver, new model-specific EPP handling in intel_pstate and more. Apart from that, the cpufreq default transition delay is reduced from 10 ms to 2 ms (along with some related adjustments), the system suspend statistics code undergoes a significant rework and there is a usual bunch of fixes and code cleanups all over. Specifics: - Allow the Energy Model to be updated dynamically (Lukasz Luba) - Add support for LZ4 compression algorithm to the hibernation image creation and loading code (Nikhil V) - Fix and clean up system suspend statistics collection (Rafael Wysocki) - Simplify device suspend and resume handling in the power management core code (Rafael Wysocki) - Fix PCI hibernation support description (Yiwei Lin) - Make hibernation take set_memory_ro() return values into account as appropriate (Christophe Leroy) - Set mem_sleep_current during kernel command line setup to avoid an ordering issue with handling it (Maulik Shah) - Fix wake IRQs handling when pm_runtime_force_suspend() is used as a driver's system suspend callback (Qingliang Li) - Simplify pm_runtime_get_if_active() usage and add a replacement for pm_runtime_put_autosuspend() (Sakari Ailus) - Add a tracepoint for runtime_status changes tracking (Vilas Bhat) - Fix section title markdown in the runtime PM documentation (Yiwei Lin) - Enable preferred core support in the amd-pstate cpufreq driver (Meng Li) - Fix min_perf assignment in amd_pstate_adjust_perf() and make the min/max limit perf values in amd-pstate always stay within the (highest perf, lowest perf) range (Tor Vic, Meng Li) - Allow intel_pstate to assign model-specific values to strings used in the EPP sysfs interface and make it do so on Meteor Lake (Srinivas Pandruvada) - Drop long-unused cpudata::prev_cummulative_iowait from the intel_pstate cpufreq driver (Jiri Slaby) - Prevent scaling_cur_freq from exceeding scaling_max_freq when the latter is an inefficient frequency (Shivnandan Kumar) - Change default transition delay in cpufreq to 2ms (Qais Yousef) - Remove references to 10ms minimum sampling rate from comments in the cpufreq code (Pierre Gondois) - Honour transition_latency over transition_delay_us in cpufreq (Qais Yousef) - Stop unregistering cpufreq cooling on CPU hot-remove (Viresh Kumar) - General enhancements / cleanups to ARM cpufreq drivers (tianyu2, Nícolas F. R. A. Prado, Erick Archer, Arnd Bergmann, Anastasia Belova) - Update cpufreq-dt-platdev to block/approve devices (Richard Acayan) - Make the SCMI cpufreq driver get a transition delay value from firmware (Pierre Gondois) - Prevent the haltpoll cpuidle governor from shrinking guest poll_limit_ns below grow_start (Parshuram Sangle) - Avoid potential overflow in integer multiplication when computing cpuidle state parameters (C Cheng) - Adjust MWAIT hint target C-state computation in the ACPI cpuidle driver and in intel_idle to return a correct value for C0 (He Rongguang) - Address multiple issues in the TPMI RAPL driver and add support for new platforms (Lunar Lake-M, Arrow Lake) to Intel RAPL (Zhang Rui) - Fix freq_qos_add_request() return value check in dtpm_cpu (Daniel Lezcano) - Fix kernel-doc for dtpm_create_hierarchy() (Yang Li) - Fix file leak in get_pkg_num() in x86_energy_perf_policy (Samasth Norway Ananda) - Fix cpupower-frequency-info.1 man page typo (Jan Kratochvil) - Fix a couple of warnings in the OPP core code related to W=1 builds (Viresh Kumar) - Move dev_pm_opp_{init|free}_cpufreq_table() to pm_opp.h (Viresh Kumar) - Extend dev_pm_opp_data with turbo support (Sibi Sankar) - dt-bindings: drop maxItems from inner items (David Heidelberg)" * tag 'pm-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (95 commits) dt-bindings: opp: drop maxItems from inner items OPP: debugfs: Fix warning around icc_get_name() OPP: debugfs: Fix warning with W=1 builds cpufreq: Move dev_pm_opp_{init|free}_cpufreq_table() to pm_opp.h OPP: Extend dev_pm_opp_data with turbo support Fix cpupower-frequency-info.1 man page typo cpufreq: scmi: Set transition_delay_us firmware: arm_scmi: Populate fast channel rate_limit firmware: arm_scmi: Populate perf commands rate_limit cpuidle: ACPI/intel: fix MWAIT hint target C-state computation PM: sleep: wakeirq: fix wake irq warning in system suspend powercap: dtpm: Fix kernel-doc for dtpm_create_hierarchy() function cpufreq: Don't unregister cpufreq cooling on CPU hotplug PM: suspend: Set mem_sleep_current during kernel command line setup cpufreq: Honour transition_latency over transition_delay_us cpufreq: Limit resolving a frequency to policy min/max Documentation: PM: Fix runtime_pm.rst markdown syntax cpufreq: amd-pstate: adjust min/max limit perf cpufreq: Remove references to 10ms min sampling rate cpufreq: intel_pstate: Update default EPPs for Meteor Lake ...
2024-03-13Merge tag 'gpio-updates-for-v6.9-rc1' of ↵Linus Torvalds4-170/+24
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: "The biggest feature is the locking overhaul. Up until now the synchronization in the GPIO subsystem was broken. There was a single spinlock "protecting" multiple data structures but doing it wrong (as evidenced by several places where it would be released when a sleeping function was called and then reacquired without checking the protected state). We tried to use an RW semaphore before but the main issue with GPIO is that we have drivers implementing the interfaces in both sleeping and non-sleeping ways as well as user-facing interfaces that can be called both from process as well as atomic contexts. Both ends converge in the same code paths that can use neither spinlocks nor mutexes. The only reasonable way out is to use SRCU and go mostly lockless. To that end: we add several SRCU structs in relevant places and use them to assure consistency between API calls together with atomic reads and writes of GPIO descriptor flags where it makes sense. This code has spent several weeks in next and has received several fixes in the first week or two after which it stabilized nicely. The GPIO subsystem is now resilient to providers being suddenly unbound. We managed to also remove the existing character device RW semaphore and the obsolete global spinlock. Other than the locking rework we have one new driver (for Chromebook EC), much appreciated documentation improvements from Kent and the regular driver improvements, DT-bindings updates and GPIOLIB core tweaks. Serialization rework: - use SRCU to serialize access to the global GPIO device list, to GPIO device structs themselves and to GPIO descriptors - make the GPIO subsystem resilient to the GPIO providers being unbound while the API calls are in progress - don't dereference the SRCU-protected chip pointer if the information we need can be obtained from the GPIO device structure - move some of the information contained in struct gpio_chip to struct gpio_device to further reduce the need to dereference the former - pass the GPIO device struct instead of the GPIO chip to sysfs callback to, again, reduce the need for accessing the latter - get GPIO descriptors from the GPIO device, not from the chip for the same reason - allow for mostly lockless operation of the GPIO driver API: assure consistency with SRCU and atomic operations - remove the global GPIO spinlock - remove the character device RW semaphore Core GPIOLIB: - constify pointers in GPIO API where applicable - unify the GPIO counting APIs for ACPI and OF - provide a macro for iterating over all GPIOs, not only the ones that are requested - remove leftover typedefs - pass the consumer device to GPIO core in devm_fwnode_gpiod_get_index() for improved logging - constify the GPIO bus type - don't warn about removing GPIO chips with descriptors still held by users as we can now handle this situation gracefully - remove unused logging helpers - unexport functions that are only used internally in the GPIO subsystem - set the device type (assign the relevant struct device_type) for GPIO devices New drivers: - add the ChromeOS EC GPIO driver Driver improvements: - allow building gpio-vf610 with COMPILE_TEST as well as disabling it in menuconfig (before it was always built for i.MX cofigs) - count the number of EICs using the device properties instead of hard-coding it in gpio-eic-sprd - improve the device naming, extend the debugfs output and add lockdep asserts to gpio-sim DT bindings: - document the 'label' property for gpio-pca9570 - convert aspeed,ast2400-gpio bindings to DT schema - disallow unevaluated properties for gpio-mvebu - document a new model in renesas,rcar-gpio Documentation: - improve the character device kerneldocs in user-space headers - add proper documentation for the character device uAPI (both v1 and v2) - move the sysfs and gpio-mockup docs into the "obsolete" section - improve naming consistency for GPIO terms - clarify the line values description for sysfs - minor docs improvements - improve the driver API contract for setting GPIO direction - mark unsafe APIs as deprecated in kerneldocs and suggest replacements Other: - remove an obsolete test from selftests" * tag 'gpio-updates-for-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (79 commits) gpio: sysfs: repair export returning -EPERM on 1st attempt selftest: gpio: remove obsolete gpio-mockup test gpiolib: Deduplicate cleanup for-loop in gpiochip_add_data_with_key() dt-bindings: gpio: aspeed,ast2400-gpio: Convert to DT schema gpio: acpi: Make acpi_gpio_count() take firmware node as a parameter gpio: of: Make of_gpio_get_count() take firmware node as a parameter gpiolib: Pass consumer device through to core in devm_fwnode_gpiod_get_index() gpio: sim: use for_each_hwgpio() gpio: provide for_each_hwgpio() gpio: don't warn about removing GPIO chips with active users anymore gpio: sim: delimit the fwnode name with a ":" when generating labels gpio: sim: add lockdep asserts gpio: Add ChromeOS EC GPIO driver gpio: constify of_phandle_args in of_find_gpio_device_by_xlate() gpio: fix memory leak in gpiod_request_commit() gpio: constify opaque pointer "data" in gpio_device_find() gpio: cdev: fix a NULL-pointer dereference with DEBUG enabled gpio: uapi: clarify default_values being logical gpio: sysfs: fix inverted pointer logic gpio: don't let lockdep complain about inherently dangerous RCU usage ...
2024-03-13Merge tag 'for-6.9/dm-vdo' of ↵Linus Torvalds3-0/+1041
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper VDO target from Mike Snitzer: "Introduce the DM vdo target which provides block-level deduplication, compression, and thin provisioning. Please see: Documentation/admin-guide/device-mapper/vdo.rst Documentation/admin-guide/device-mapper/vdo-design.rst The DM vdo target handles its concurrency by pinning an IO, and subsequent stages of handling that IO, to a particular VDO thread. This aspect of VDO is "unique" but its overall implementation is very tightly coupled to its mostly lockless threading model. As such, VDO is not easily changed to use more traditional finer-grained locking and Linux workqueues. Please see the "Zones and Threading" section of vdo-design.rst The DM vdo target has been used in production for many years but has seen significant changes over the past ~6 years to prepare it for upstream inclusion. The codebase is still large but it is isolated to drivers/md/dm-vdo/ and has been made considerably more approachable and maintainable. Matt Sakai has been added to the MAINTAINERS file to reflect that he will send VDO changes upstream through the DM subsystem maintainers" * tag 'for-6.9/dm-vdo' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (142 commits) dm vdo: document minimum metadata size requirements dm vdo: remove meaningless version number constant dm vdo: remove vdo_perform_once dm vdo block-map: Remove stray semicolon dm vdo string-utils: change from uds_ to vdo_ namespace dm vdo logger: change from uds_ to vdo_ namespace dm vdo funnel-queue: change from uds_ to vdo_ namespace dm vdo indexer: fix use after free dm vdo logger: remove log level to string conversion code dm vdo: document log_level parameter dm vdo: add 'log_level' module parameter dm vdo: remove all sysfs interfaces dm vdo target: eliminate inappropriate uses of UDS_SUCCESS dm vdo indexer: update ASSERT and ASSERT_LOG_ONLY usage dm vdo encodings: update some stale comments dm vdo permassert: audit all of ASSERT to test for VDO_SUCCESS dm-vdo funnel-workqueue: return VDO_SUCCESS from make_simple_work_queue dm vdo thread-utils: return VDO_SUCCESS on vdo_create_thread success dm vdo int-map: return VDO_SUCCESS on success dm vdo: check for VDO_SUCCESS return value from memory-alloc functions ...
2024-03-13Merge tag 'slab-for-6.9' of ↵Linus Torvalds1-43/+32
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab updates from Vlastimil Babka: - Freelist loading optimization (Chengming Zhou) When the per-cpu slab is depleted and a new one loaded from the cpu partial list, optimize the loading to avoid an irq enable/disable cycle. This results in a 3.5% performance improvement on the "perf bench sched messaging" test. - Kernel boot parameters cleanup after SLAB removal (Xiongwei Song) Due to two different main slab implementations we've had boot parameters prefixed either slab_ and slub_ with some later becoming an alias as both implementations gained the same functionality (i.e. slab_nomerge vs slub_nomerge). In order to eventually get rid of the implementation-specific names, the canonical and documented parameters are now all prefixed slab_ and the slub_ variants become deprecated but still working aliases. - SLAB_ kmem_cache creation flags cleanup (Vlastimil Babka) The flags had hardcoded #define values which became tedious and error-prone when adding new ones. Assign the values via an enum that takes care of providing unique bit numbers. Also deprecate SLAB_MEM_SPREAD which was only used by SLAB, so it's a no-op since SLAB removal. Assign it an explicit zero value. The removals of the flag usage are handled independently in the respective subsystems, with a final removal of any leftover usage planned for the next release. - Misc cleanups and fixes (Chengming Zhou, Xiaolei Wang, Zheng Yejian) Includes removal of unused code or function parameters and a fix of a memleak. * tag 'slab-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: slab: remove PARTIAL_NODE slab_state mm, slab: remove memcg_from_slab_obj() mm, slab: remove the corner case of inc_slabs_node() mm/slab: Fix a kmemleak in kmem_cache_destroy() mm, slab, kasan: replace kasan_never_merge() with SLAB_NO_MERGE mm, slab: use an enum to define SLAB_ cache creation flags mm, slab: deprecate SLAB_MEM_SPREAD flag mm, slab: fix the comment of cpu partial list mm, slab: remove unused object_size parameter in kmem_cache_flags() mm/slub: remove parameter 'flags' in create_kmalloc_caches() mm/slub: remove unused parameter in next_freelist_entry() mm/slub: remove full list manipulation for non-debug slab mm/slub: directly load freelist from cpu partial slab in the likely case mm/slub: make the description of slab_min_objects helpful in doc mm/slub: replace slub_$params with slab_$params in slub.rst mm/slub: unify all sl[au]b parameters with "slab_$param" Documentation: kernel-parameters: remove noaliencache
2024-03-13Merge tag 'net-next-6.9' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core & protocols: - Large effort by Eric to lower rtnl_lock pressure and remove locks: - Make commonly used parts of rtnetlink (address, route dumps etc) lockless, protected by RCU instead of rtnl_lock. - Add a netns exit callback which already holds rtnl_lock, allowing netns exit to take rtnl_lock once in the core instead of once for each driver / callback. - Remove locks / serialization in the socket diag interface. - Remove 6 calls to synchronize_rcu() while holding rtnl_lock. - Remove the dev_base_lock, depend on RCU where necessary. - Support busy polling on a per-epoll context basis. Poll length and budget parameters can be set independently of system defaults. - Introduce struct net_hotdata, to make sure read-mostly global config variables fit in as few cache lines as possible. - Add optional per-nexthop statistics to ease monitoring / debug of ECMP imbalance problems. - Support TCP_NOTSENT_LOWAT in MPTCP. - Ensure that IPv6 temporary addresses' preferred lifetimes are long enough, compared to other configured lifetimes, and at least 2 sec. - Support forwarding of ICMP Error messages in IPSec, per RFC 4301. - Add support for the independent control state machine for bonding per IEEE 802.1AX-2008 5.4.15 in addition to the existing coupled control state machine. - Add "network ID" to MCTP socket APIs to support hosts with multiple disjoint MCTP networks. - Re-use the mono_delivery_time skbuff bit for packets which user space wants to be sent at a specified time. Maintain the timing information while traversing veth links, bridge etc. - Take advantage of MSG_SPLICE_PAGES for RxRPC DATA and ACK packets. - Simplify many places iterating over netdevs by using an xarray instead of a hash table walk (hash table remains in place, for use on fastpaths). - Speed up scanning for expired routes by keeping a dedicated list. - Speed up "generic" XDP by trying harder to avoid large allocations. - Support attaching arbitrary metadata to netconsole messages. Things we sprinkled into general kernel code: - Enforce VM_IOREMAP flag and range in ioremap_page_range and introduce VM_SPARSE kind and vm_area_[un]map_pages (used by bpf_arena). - Rework selftest harness to enable the use of the full range of ksft exit code (pass, fail, skip, xfail, xpass). Netfilter: - Allow userspace to define a table that is exclusively owned by a daemon (via netlink socket aliveness) without auto-removing this table when the userspace program exits. Such table gets marked as orphaned and a restarting management daemon can re-attach/regain ownership. - Speed up element insertions to nftables' concatenated-ranges set type. Compact a few related data structures. BPF: - Add BPF token support for delegating a subset of BPF subsystem functionality from privileged system-wide daemons such as systemd through special mount options for userns-bound BPF fs to a trusted & unprivileged application. - Introduce bpf_arena which is sparse shared memory region between BPF program and user space where structures inside the arena can have pointers to other areas of the arena, and pointers work seamlessly for both user-space programs and BPF programs. - Introduce may_goto instruction that is a contract between the verifier and the program. The verifier allows the program to loop assuming it's behaving well, but reserves the right to terminate it. - Extend the BPF verifier to enable static subprog calls in spin lock critical sections. - Support registration of struct_ops types from modules which helps projects like fuse-bpf that seeks to implement a new struct_ops type. - Add support for retrieval of cookies for perf/kprobe multi links. - Support arbitrary TCP SYN cookie generation / validation in the TC layer with BPF to allow creating SYN flood handling in BPF firewalls. - Add code generation to inline the bpf_kptr_xchg() helper which improves performance when stashing/popping the allocated BPF objects. Wireless: - Add SPP (signaling and payload protected) AMSDU support. - Support wider bandwidth OFDMA, as required for EHT operation. Driver API: - Major overhaul of the Energy Efficient Ethernet internals to support new link modes (2.5GE, 5GE), share more code between drivers (especially those using phylib), and encourage more uniform behavior. Convert and clean up drivers. - Define an API for querying per netdev queue statistics from drivers. - IPSec: account in global stats for fully offloaded sessions. - Create a concept of Ethernet PHY Packages at the Device Tree level, to allow parameterizing the existing PHY package code. - Enable Rx hashing (RSS) on GTP protocol fields. Misc: - Improvements and refactoring all over networking selftests. - Create uniform module aliases for TC classifiers, actions, and packet schedulers to simplify creating modprobe policies. - Address all missing MODULE_DESCRIPTION() warnings in networking. - Extend the Netlink descriptions in YAML to cover message encapsulation or "Netlink polymorphism", where interpretation of nested attributes depends on link type, classifier type or some other "class type". Drivers: - Ethernet high-speed NICs: - Add a new driver for Marvell's Octeon PCI Endpoint NIC VF. - Intel (100G, ice, idpf): - support E825-C devices - nVidia/Mellanox: - support devices with one port and multiple PCIe links - Broadcom (bnxt): - support n-tuple filters - support configuring the RSS key - Wangxun (ngbe/txgbe): - implement irq_domain for TXGBE's sub-interrupts - Pensando/AMD: - support XDP - optimize queue submission and wakeup handling (+17% bps) - optimize struct layout, saving 28% of memory on queues - Ethernet NICs embedded and virtual: - Google cloud vNIC: - refactor driver to perform memory allocations for new queue config before stopping and freeing the old queue memory - Synopsys (stmmac): - obey queueMaxSDU and implement counters required by 802.1Qbv - Renesas (ravb): - support packet checksum offload - suspend to RAM and runtime PM support - Ethernet switches: - nVidia/Mellanox: - support for nexthop group statistics - Microchip: - ksz8: implement PHY loopback - add support for KSZ8567, a 7-port 10/100Mbps switch - PTP: - New driver for RENESAS FemtoClock3 Wireless clock generator. - Support OCP PTP cards designed and built by Adva. - CAN: - Support recvmsg() flags for own, local and remote traffic on CAN BCM sockets. - Support for esd GmbH PCIe/402 CAN device family. - m_can: - Rx/Tx submission coalescing - wake on frame Rx - WiFi: - Intel (iwlwifi): - enable signaling and payload protected A-MSDUs - support wider-bandwidth OFDMA - support for new devices - bump FW API to 89 for AX devices; 90 for BZ/SC devices - MediaTek (mt76): - mt7915: newer ADIE version support - mt7925: radio temperature sensor support - Qualcomm (ath11k): - support 6 GHz station power modes: Low Power Indoor (LPI), Standard Power) SP and Very Low Power (VLP) - QCA6390 & WCN6855: support 2 concurrent station interfaces - QCA2066 support - Qualcomm (ath12k): - refactoring in preparation for Multi-Link Operation (MLO) support - 1024 Block Ack window size support - firmware-2.bin support - support having multiple identical PCI devices (firmware needs to have ATH12K_FW_FEATURE_MULTI_QRTR_ID) - QCN9274: support split-PHY devices - WCN7850: enable Power Save Mode in station mode - WCN7850: P2P support - RealTek: - rtw88: support for more rtw8811cu and rtw8821cu devices - rtw89: support SCAN_RANDOM_SN and SET_SCAN_DWELL - rtlwifi: speed up USB firmware initialization - rtwl8xxxu: - RTL8188F: concurrent interface support - Channel Switch Announcement (CSA) support in AP mode - Broadcom (brcmfmac): - per-vendor feature support - per-vendor SAE password setup - DMI nvram filename quirk for ACEPC W5 Pro" * tag 'net-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2255 commits) nexthop: Fix splat with CONFIG_DEBUG_PREEMPT=y nexthop: Fix out-of-bounds access during attribute validation nexthop: Only parse NHA_OP_FLAGS for dump messages that require it nexthop: Only parse NHA_OP_FLAGS for get messages that require it bpf: move sleepable flag from bpf_prog_aux to bpf_prog bpf: hardcode BPF_PROG_PACK_SIZE to 2MB * num_possible_nodes() selftests/bpf: Add kprobe multi triggering benchmarks ptp: Move from simple ida to xarray vxlan: Remove generic .ndo_get_stats64 vxlan: Do not alloc tstats manually devlink: Add comments to use netlink gen tool nfp: flower: handle acti_netdevs allocation failure net/packet: Add getsockopt support for PACKET_COPY_THRESH net/netlink: Add getsockopt support for NETLINK_LISTEN_ALL_NSID selftests/bpf: Add bpf_arena_htab test. selftests/bpf: Add bpf_arena_list test. selftests/bpf: Add unit tests for bpf_arena_alloc/free_pages bpf: Add helper macro bpf_addr_space_cast() libbpf: Recognize __arena global variables. bpftool: Recognize arena map type ...
2024-03-13Merge tag 'docs-6.9' of git://git.lwn.net/linuxLinus Torvalds5-26/+2006
Pull documentation updates from Jonathan Corbet: "A moderatly busy cycle for development this time around. - Some cleanup of the main index page for easier navigation - Rework some of the other top-level pages for better readability and, with luck, fewer merge conflicts in the future. - Submit-checklist improvements, hopefully the first of many. - New Italian translations - A fair number of kernel-doc fixes and improvements. We have also dropped the recommendation to use an old version of Sphinx. - A new document from Thorsten on bisection ... and lots of fixes and updates" * tag 'docs-6.9' of git://git.lwn.net/linux: (54 commits) docs: verify/bisect: fixes, finetuning, and support for Arch docs: Makefile: Add dependency to $(YNL_INDEX) for targets other than htmldocs docs: Move ja_JP/howto.rst to ja_JP/process/howto.rst docs: submit-checklist: use subheadings docs: submit-checklist: structure by category docs: new text on bisecting which also covers bug validation docs: drop the version constraints for sphinx and dependencies docs: kerneldoc-preamble.sty: Remove code for Sphinx <2.4 docs: Restore "smart quotes" for quotes docs/zh_CN: accurate translation of "function" docs: Include simplified link titles in main index docs: Correct formatting of title in admin-guide/index.rst docs: kernel_feat.py: fix build error for missing files MAINTAINERS: Set the field name for subsystem profile section kasan: Add documentation for CONFIG_KASAN_EXTRA_INFO Fixed case issue with 'fault-injection' in documentation kernel-doc: handle #if in enums as well Documentation: update mailing list addresses doc: kerneldoc.py: fix indentation scripts/kernel-doc: simplify signature printing ...
2024-03-12Merge tag 'rfds-for-linus-2024-03-11' of ↵Linus Torvalds3-0/+126
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RFDS mitigation from Dave Hansen: "RFDS is a CPU vulnerability that may allow a malicious userspace to infer stale register values from kernel space. Kernel registers can have all kinds of secrets in them so the mitigation is basically to wait until the kernel is about to return to userspace and has user values in the registers. At that point there is little chance of kernel secrets ending up in the registers and the microarchitectural state can be cleared. This leverages some recent robustness fixes for the existing MDS vulnerability. Both MDS and RFDS use the VERW instruction for mitigation" * tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests x86/rfds: Mitigate Register File Data Sampling (RFDS) Documentation/hw-vuln: Add documentation for RFDS x86/mmio: Disable KVM mitigation when X86_FEATURE_CLEAR_CPU_BUF is set
2024-03-12Merge tag 'x86-core-2024-03-11' of ↵Linus Torvalds2-6/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: - The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code - Propagate more RIP-relative addressing in assembly code, to generate slightly better code - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options - Rework the x86 idle code to cure RCU violations and to clean up the logic - Clean up the vDSO Makefile logic - Misc cleanups and fixes * tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) x86/idle: Select idle routine only once x86/idle: Let prefer_mwait_c1_over_halt() return bool x86/idle: Cleanup idle_setup() x86/idle: Clean up idle selection x86/idle: Sanitize X86_BUG_AMD_E400 handling sched/idle: Conditionally handle tick broadcast in default_idle_call() x86: Increase brk randomness entropy for 64-bit systems x86/vdso: Move vDSO to mmap region x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o x86/retpoline: Ensure default return thunk isn't used at runtime x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32 x86/vdso: Use $(addprefix ) instead of $(foreach ) x86/vdso: Simplify obj-y addition x86/vdso: Consolidate targets and clean-files x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS ...
2024-03-12Merge tag 'edac_updates_for_v6.9' of ↵Linus Torvalds5-4/+60
git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras Pull EDAC updates from Borislav Petkov: - Add a FRU (Field Replaceable Unit) memory poison manager which collects and manages previously encountered hw errors in order to save them to persistent storage across reboots. Previously recorded errors are "replayed" upon reboot in order to poison memory which has caused said errors in the past. The main use case is stacked, on-chip memory which cannot simply be replaced so poisoning faulty areas of it and thus making them inaccessible is the only strategy to prolong its lifetime. - Add an AMD address translation library glue which converts the reported addresses of hw errors into system physical addresses in order to be used by other subsystems like memory failure, for example. Add support for MI300 accelerators to that library. - igen6: Add support for Alder Lake-N SoC - i10nm: Add Grand Ridge support - The usual fixlets and cleanups * tag 'edac_updates_for_v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras: EDAC/versal: Convert to platform remove callback returning void RAS/AMD/FMPM: Fix off by one when unwinding on error RAS/AMD/FMPM: Add debugfs interface to print record entries RAS/AMD/FMPM: Save SPA values RAS: Export helper to get ras_debugfs_dir RAS/AMD/ATL: Fix bit overflow in denorm_addr_df4_np2() RAS: Introduce a FRU memory poison manager RAS/AMD/ATL: Add MI300 row retirement support Documentation: Move RAS section to admin-guide EDAC/versal: Make the bit position of injected errors configurable EDAC/i10nm: Add Intel Grand Ridge micro-server support EDAC/igen6: Add one more Intel Alder Lake-N SoC support RAS/AMD/ATL: Add MI300 DRAM to normalized address translation support RAS/AMD/ATL: Fix array overflow in get_logical_coh_st_fabric_id_mi300() RAS/AMD/ATL: Add MI300 support Documentation: RAS: Add index and address translation section EDAC/amd64: Use new AMD Address Translation Library RAS: Introduce AMD Address Translation Library EDAC/synopsys: Convert to devm_platform_ioremap_resource()
2024-03-12Merge tag 'x86_misc_for_v6.9_rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 fixes from Borislav Petkov: - Fix a wrong check in the function reporting whether a CPU executes (or not) a NMI handler - Ratelimit unknown NMIs messages in order to not potentially slow down the machine - Other fixlets * tag 'x86_misc_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Fix the inverse "in NMI handler" check Documentation/maintainer-tip: Add C++ tail comments exception Documentation/maintainer-tip: Add Closes tag x86/nmi: Rate limit unknown NMI messages Documentation/kernel-parameters: Add spec_rstack_overflow to mitigations=off
2024-03-12Merge tag 'x86_sev_for_v6.9_rc1' of ↵Linus Torvalds1-3/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV updates from Borislav Petkov: - Add the x86 part of the SEV-SNP host support. This will allow the kernel to be used as a KVM hypervisor capable of running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP is the ultimate goal of the AMD confidential computing side, providing the most comprehensive confidential computing environment up to date. This is the x86 part and there is a KVM part which did not get ready in time for the merge window so latter will be forthcoming in the next cycle. - Rework the early code's position-dependent SEV variable references in order to allow building the kernel with clang and -fPIE/-fPIC and -mcmodel=kernel - The usual set of fixes, cleanups and improvements all over the place * tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) x86/sev: Disable KMSAN for memory encryption TUs x86/sev: Dump SEV_STATUS crypto: ccp - Have it depend on AMD_IOMMU iommu/amd: Fix failure return from snp_lookup_rmpentry() x86/sev: Fix position dependent variable references in startup code crypto: ccp: Make snp_range_list static x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT Documentation: virt: Fix up pre-formatted text block for SEV ioctls crypto: ccp: Add the SNP_SET_CONFIG command crypto: ccp: Add the SNP_COMMIT command crypto: ccp: Add the SNP_PLATFORM_STATUS command x86/cpufeatures: Enable/unmask SEV-SNP CPU feature KVM: SEV: Make AVIC backing, VMSA and VMCB memory allocation SNP safe crypto: ccp: Add panic notifier for SEV/SNP firmware shutdown on kdump iommu/amd: Clean up RMP entries for IOMMU pages during SNP shutdown crypto: ccp: Handle legacy SEV commands when SNP is enabled crypto: ccp: Handle non-volatile INIT_EX data when SNP is enabled crypto: ccp: Handle the legacy TMR allocation when SNP is enabled x86/sev: Introduce an SNP leaked pages list crypto: ccp: Provide an API to issue SEV and SNP commands ...
2024-03-12Merge tag 'x86-fred-2024-03-10' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 FRED support from Thomas Gleixner: "Support for x86 Fast Return and Event Delivery (FRED). FRED is a replacement for IDT event delivery on x86 and addresses most of the technical nightmares which IDT exposes: 1) Exception cause registers like CR2 need to be manually preserved in nested exception scenarios. 2) Hardware interrupt stack switching is suboptimal for nested exceptions as the interrupt stack mechanism rewinds the stack on each entry which requires a massive effort in the low level entry of #NMI code to handle this. 3) No hardware distinction between entry from kernel or from user which makes establishing kernel context more complex than it needs to be especially for unconditionally nestable exceptions like NMI. 4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a problem when the perf NMI takes a fault when collecting a stack trace. 5) Partial restore of ESP when returning to a 16-bit segment 6) Limitation of the vector space which can cause vector exhaustion on large systems. 7) Inability to differentiate NMI sources FRED addresses these shortcomings by: 1) An extended exception stack frame which the CPU uses to save exception cause registers. This ensures that the meta information for each exception is preserved on stack and avoids the extra complexity of preserving it in software. 2) Hardware interrupt stack switching is non-rewinding if a nested exception uses the currently interrupt stack. 3) The entry points for kernel and user context are separate and GS BASE handling which is required to establish kernel context for per CPU variable access is done in hardware. 4) NMIs are now nesting protected. They are only reenabled on the return from NMI. 5) FRED guarantees full restore of ESP 6) FRED does not put a limitation on the vector space by design because it uses a central entry points for kernel and user space and the CPUstores the entry type (exception, trap, interrupt, syscall) on the entry stack along with the vector number. The entry code has to demultiplex this information, but this removes the vector space restriction. The first hardware implementations will still have the current restricted vector space because lifting this limitation requires further changes to the local APIC. 7) FRED stores the vector number and meta information on stack which allows having more than one NMI vector in future hardware when the required local APIC changes are in place. The series implements the initial FRED support by: - Reworking the existing entry and IDT handling infrastructure to accomodate for the alternative entry mechanism. - Expanding the stack frame to accomodate for the extra 16 bytes FRED requires to store context and meta information - Providing FRED specific C entry points for events which have information pushed to the extended stack frame, e.g. #PF and #DB. - Providing FRED specific C entry points for #NMI and #MCE - Implementing the FRED specific ASM entry points and the C code to demultiplex the events - Providing detection and initialization mechanisms and the necessary tweaks in context switching, GS BASE handling etc. The FRED integration aims for maximum code reuse vs the existing IDT implementation to the extent possible and the deviation in hot paths like context switching are handled with alternatives to minimalize the impact. The low level entry and exit paths are seperate due to the extended stack frame and the hardware based GS BASE swichting and therefore have no impact on IDT based systems. It has been extensively tested on existing systems and on the FRED simulation and as of now there are no outstanding problems" * tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) x86/fred: Fix init_task thread stack pointer initialization MAINTAINERS: Add a maintainer entry for FRED x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly x86/fred: Invoke FRED initialization code to enable FRED x86/fred: Add FRED initialization functions x86/syscall: Split IDT syscall setup code into idt_syscall_init() KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled x86/traps: Add sysvec_install() to install a system interrupt handler x86/fred: FRED entry/exit and dispatch code x86/fred: Add a machine check entry stub for FRED x86/fred: Add a NMI entry stub for FRED x86/fred: Add a debug fault entry stub for FRED x86/idtentry: Incorporate definitions/declarations of the FRED entries x86/fred: Make exc_page_fault() work for FRED x86/fred: Allow single-step trap and NMI when starting a new task x86/fred: No ESPFIX needed when FRED is enabled ...
2024-03-12Merge tag 'x86-apic-2024-03-10' of ↵Linus Torvalds2-14/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Thomas Gleixner: "Rework of APIC enumeration and topology evaluation. The current implementation has a couple of shortcomings: - It fails to handle hybrid systems correctly. - The APIC registration code which handles CPU number assignents is in the middle of the APIC code and detached from the topology evaluation. - The various mechanisms which enumerate APICs, ACPI, MPPARSE and guest specific ones, tweak global variables as they see fit or in case of XENPV just hack around the generic mechanisms completely. - The CPUID topology evaluation code is sprinkled all over the vendor code and reevaluates global variables on every hotplug operation. - There is no way to analyze topology on the boot CPU before bringing up the APs. This causes problems for infrastructure like PERF which needs to size certain aspects upfront or could be simplified if that would be possible. - The APIC admission and CPU number association logic is incomprehensible and overly complex and needs to be kept around after boot instead of completing this right after the APIC enumeration. This update addresses these shortcomings with the following changes: - Rework the CPUID evaluation code so it is common for all vendors and provides information about the APIC ID segments in a uniform way independent of the number of segments (Thread, Core, Module, ..., Die, Package) so that this information can be computed instead of rewriting global variables of dubious value over and over. - A few cleanups and simplifcations of the APIC, IO/APIC and related interfaces to prepare for the topology evaluation changes. - Seperation of the parser stages so the early evaluation which tries to find the APIC address can be seperately overridden from the late evaluation which enumerates and registers the local APIC as further preparation for sanitizing the topology evaluation. - A new registration and admission logic which - encapsulates the inner workings so that parsers and guest logic cannot longer fiddle in it - uses the APIC ID segments to build topology bitmaps at registration time - provides a sane admission logic - allows to detect the crash kernel case, where CPU0 does not run on the real BSP, automatically. This is required to prevent sending INIT/SIPI sequences to the real BSP which would reset the whole machine. This was so far handled by a tedious command line parameter, which does not even work in nested crash scenarios. - Associates CPU number after the enumeration completed and prevents the late registration of APICs, which was somehow tolerated before. - Converting all parsers and guest enumeration mechanisms over to the new interfaces. This allows to get rid of all global variable tweaking from the parsers and enumeration mechanisms and sanitizes the XEN[PV] handling so it can use CPUID evaluation for the first time. - Mopping up existing sins by taking the information from the APIC ID segment bitmaps. This evaluates hybrid systems correctly on the boot CPU and allows for cleanups and fixes in the related drivers, e.g. PERF. The series has been extensively tested and the minimal late fallout due to a broken ACPI/MADT table has been addressed by tightening the admission logic further" * tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits) x86/topology: Ignore non-present APIC IDs in a present package x86/apic: Build the x86 topology enumeration functions on UP APIC builds too smp: Provide 'setup_max_cpus' definition on UP too smp: Avoid 'setup_max_cpus' namespace collision/shadowing x86/bugs: Use fixed addressing for VERW operand x86/cpu/topology: Get rid of cpuinfo::x86_max_cores x86/cpu/topology: Provide __num_[cores|threads]_per_package x86/cpu/topology: Rename topology_max_die_per_package() x86/cpu/topology: Rename smp_num_siblings x86/cpu/topology: Retrieve cores per package from topology bitmaps x86/cpu/topology: Use topology logical mapping mechanism x86/cpu/topology: Provide logical pkg/die mapping x86/cpu/topology: Simplify cpu_mark_primary_thread() x86/cpu/topology: Mop up primary thread mask handling x86/cpu/topology: Use topology bitmaps for sizing x86/cpu/topology: Let XEN/PV use topology from CPUID/MADT x86/xen/smp_pv: Count number of vCPUs early x86/cpu/topology: Assign hotpluggable CPUIDs during init x86/cpu/topology: Reject unknown APIC IDs on ACPI hotplug x86/topology: Add a mechanism to track topology via APIC IDs ...
2024-03-12Merge tag 'timers-core-2024-03-10' of ↵Linus Torvalds1-6/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "A large set of updates and features for timers and timekeeping: - The hierarchical timer pull model When timer wheel timers are armed they are placed into the timer wheel of a CPU which is likely to be busy at the time of expiry. This is done to avoid wakeups on potentially idle CPUs. This is wrong in several aspects: 1) The heuristics to select the target CPU are wrong by definition as the chance to get the prediction right is close to zero. 2) Due to #1 it is possible that timers are accumulated on a single target CPU 3) The required computation in the enqueue path is just overhead for dubious value especially under the consideration that the vast majority of timer wheel timers are either canceled or rearmed before they expire. The timer pull model avoids the above by removing the target computation on enqueue and queueing timers always on the CPU on which they get armed. This is achieved by having separate wheels for CPU pinned timers and global timers which do not care about where they expire. As long as a CPU is busy it handles both the pinned and the global timers which are queued on the CPU local timer wheels. When a CPU goes idle it evaluates its own timer wheels: - If the first expiring timer is a pinned timer, then the global timers can be ignored as the CPU will wake up before they expire. - If the first expiring timer is a global timer, then the expiry time is propagated into the timer pull hierarchy and the CPU makes sure to wake up for the first pinned timer. The timer pull hierarchy organizes CPUs in groups of eight at the lowest level and at the next levels groups of eight groups up to the point where no further aggregation of groups is required, i.e. the number of levels is log8(NR_CPUS). The magic number of eight has been established by experimention, but can be adjusted if needed. In each group one busy CPU acts as the migrator. It's only one CPU to avoid lock contention on remote timer wheels. The migrator CPU checks in its own timer wheel handling whether there are other CPUs in the group which have gone idle and have global timers to expire. If there are global timers to expire, the migrator locks the remote CPU timer wheel and handles the expiry. Depending on the group level in the hierarchy this handling can require to walk the hierarchy downwards to the CPU level. Special care is taken when the last CPU goes idle. At this point the CPU is the systemwide migrator at the top of the hierarchy and it therefore cannot delegate to the hierarchy. It needs to arm its own timer device to expire either at the first expiring timer in the hierarchy or at the first CPU local timer, which ever expires first. This completely removes the overhead from the enqueue path, which is e.g. for networking a true hotpath and trades it for a slightly more complex idle path. This has been in development for a couple of years and the final series has been extensively tested by various teams from silicon vendors and ran through extensive CI. There have been slight performance improvements observed on network centric workloads and an Intel team confirmed that this allows them to power down a die completely on a mult-die socket for the first time in a mostly idle scenario. There is only one outstanding ~1.5% regression on a specific overloaded netperf test which is currently investigated, but the rest is either positive or neutral performance wise and positive on the power management side. - Fixes for the timekeeping interpolation code for cross-timestamps: cross-timestamps are used for PTP to get snapshots from hardware timers and interpolated them back to clock MONOTONIC. The changes address a few corner cases in the interpolation code which got the math and logic wrong. - Simplifcation of the clocksource watchdog retry logic to automatically adjust to handle larger systems correctly instead of having more incomprehensible command line parameters. - Treewide consolidation of the VDSO data structures. - The usual small improvements and cleanups all over the place" * tag 'timers-core-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits) timer/migration: Fix quick check reporting late expiry tick/sched: Fix build failure for CONFIG_NO_HZ_COMMON=n vdso/datapage: Quick fix - use asm/page-def.h for ARM64 timers: Assert no next dyntick timer look-up while CPU is offline tick: Assume timekeeping is correctly handed over upon last offline idle call tick: Shut down low-res tick from dying CPU tick: Split nohz and highres features from nohz_mode tick: Move individual bit features to debuggable mask accesses tick: Move got_idle_tick away from common flags tick: Assume the tick can't be stopped in NOHZ_MODE_INACTIVE mode tick: Move broadcast cancellation up to CPUHP_AP_TICK_DYING tick: Move tick cancellation up to CPUHP_AP_TICK_DYING tick: Start centralizing tick related CPU hotplug operations tick/sched: Don't clear ts::next_tick again in can_stop_idle_tick() tick/sched: Rename tick_nohz_stop_sched_tick() to tick_nohz_full_stop_tick() tick: Use IS_ENABLED() whenever possible tick/sched: Remove useless oneshot ifdeffery tick/nohz: Remove duplicate between lowres and highres handlers tick/nohz: Remove duplicate between tick_nohz_switch_to_nohz() and tick_setup_sched_timer() hrtimer: Select housekeeping CPU during migration ...
2024-03-11x86/rfds: Mitigate Register File Data Sampling (RFDS)Pawan Gupta1-0/+21
RFDS is a CPU vulnerability that may allow userspace to infer kernel stale data previously used in floating point registers, vector registers and integer registers. RFDS only affects certain Intel Atom processors. Intel released a microcode update that uses VERW instruction to clear the affected CPU buffers. Unlike MDS, none of the affected cores support SMT. Add RFDS bug infrastructure and enable the VERW based mitigation by default, that clears the affected buffers just before exiting to userspace. Also add sysfs reporting and cmdline parameter "reg_file_data_sampling" to control the mitigation. For details see: Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-03-11Documentation/hw-vuln: Add documentation for RFDSPawan Gupta2-0/+105
Add the documentation for transient execution vulnerability Register File Data Sampling (RFDS) that affects Intel Atom CPUs. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
2024-03-11Merge tag 'cgroup-for-6.9' of ↵Linus Torvalds2-9/+13
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "A quiet cycle. One trivial doc update patch. Two patches to drop the now defunct memory_spread_slab feature from cgroup1 cpuset" * tag 'cgroup-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup/cpuset: Mark memory_spread_slab as obsolete cgroup/cpuset: Remove cpuset_do_slab_mem_spread() docs: cgroup-v1: add missing code-block tags
2024-03-11Merge tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-0/+9
Pull workqueue updates from Tejun Heo: "This cycle, a lot of workqueue changes including some that are significant and invasive. - During v6.6 cycle, unbound workqueues were updated so that they are more topology aware and flexible, which among other things improved workqueue behavior on modern multi-L3 CPUs. In the process, commit 636b927eba5b ("workqueue: Make unbound workqueues to use per-cpu pool_workqueues") switched unbound workqueues to use per-CPU frontend pool_workqueues as a part of increasing front-back mapping flexibility. An unwelcome side effect of this change was that this made max concurrency enforcement per-CPU blowing up the maximum number of allowed concurrent executions. I incorrectly assumed that this wouldn't cause practical problems as most unbound workqueue users are self-regulate max concurrency; however, there definitely are which don't (e.g. on IO paths) and the drastic increase in the allowed max concurrency led to noticeable perf regressions in some use cases. This is now addressed by separating out max concurrency enforcement to a separate struct - wq_node_nr_active - which makes @max_active consistently mean system-wide max concurrency regardless of the number of CPUs or (finally) NUMA nodes. This is a rather invasive and, in places, a bit clunky; however, the clunkiness rises from the the inherent requirement to handle the disagreement between the execution locality domain and max concurrency enforcement domain on some modern machines. See commit 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues") for more details. - BH workqueue support is added. They are similar to per-CPU workqueues but execute work items in the softirq context. This is expected to replace tasklet. However, currently, it's missing the ability to disable and enable work items which is needed to convert many tasklet users. To avoid crowding this merge window too much, this will be included in the next merge window. A separate pull request will be sent for the couple conversion patches that are currently pending. - Waiman plugged a long-standing hole in workqueue CPU isolation where ordered workqueues didn't follow wq_unbound_cpumask updates. Ordered workqueues now follow the same rules as other unbound workqueues. - More CPU isolation improvements: Juri fixed another deficit in workqueue isolation where unbound rescuers don't respect wq_unbound_cpumask. Leonardo fixed delayed_work timers firing on isolated CPUs. - Other misc changes" * tag 'wq-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (54 commits) workqueue: Drain BH work items on hot-unplugged CPUs workqueue: Introduce from_work() helper for cleaner callback declarations workqueue: Control intensive warning threshold through cmdline workqueue: Make @flags handling consistent across set_work_data() and friends workqueue: Remove clear_work_data() workqueue: Factor out work_grab_pending() from __cancel_work_sync() workqueue: Clean up enum work_bits and related constants workqueue: Introduce work_cancel_flags workqueue: Use variable name irq_flags for saving local irq flags workqueue: Reorganize flush and cancel[_sync] functions workqueue: Rename __cancel_work_timer() to __cancel_timer_sync() workqueue: Use rcu_read_lock_any_held() instead of rcu_read_lock_held() workqueue: Cosmetic changes workqueue, irq_work: Build fix for !CONFIG_IRQ_WORK workqueue: Fix queue_work_on() with BH workqueues async: Use a dedicated unbound workqueue with raised min_active workqueue: Implement workqueue_set_min_active() workqueue: Fix kernel-doc comment of unplug_oldest_pwq() workqueue: Bind unbound workqueue rescuer to wq_unbound_cpumask kernel/workqueue: Let rescuers follow unbound wq cpumask changes ...
2024-03-11Merge branch 'pm-cpufreq'Rafael J. Wysocki2-2/+62
Merge cpufreq changes for 6.9-rc1: - Enable preferred core support in the amd-pstate cpufreq driver (Meng Li). - Fix min_perf assignment in amd_pstate_adjust_perf() and make the min/max limit perf values in amd-pstate always stay within the (highest perf, lowest perf) range (Tor Vic, Meng Li). - Change default transition delay in cpufreq to 2ms (Qais Yousef). - Drop long-unused cpudata::prev_cummulative_iowait from the intel_pstate cpufreq driver (Jiri Slaby). - Allow intel_pstate to assign model-specific values to strings used in the EPP sysfs interface and make it do so on Meteor Lake (Srinivas Pandruvada). - Remove references to 10ms minimum sampling rate from comments in the cpufreq code (Pierre Gondois). - Prevent scaling_cur_freq from exceeding scaling_max_freq when the latter is an inefficient frequency (Shivnandan Kumar). - Honour transition_latency over transition_delay_us in cpufreq (Qais Yousef). - Stop unregistering cpufreq cooling on CPU hot-remove (Viresh Kumar). - General enhancements / cleanups to ARM cpufreq drivers (tianyu2, Nícolas F. R. A. Prado, Erick Archer, Arnd Bergmann, Anastasia Belova). - Update cpufreq-dt-platdev to block/approve devices (Richard Acayan). - Make the SCMI cpufreq driver get a transition delay value from firmware (Pierre Gondois). * pm-cpufreq: (28 commits) cpufreq: scmi: Set transition_delay_us firmware: arm_scmi: Populate fast channel rate_limit firmware: arm_scmi: Populate perf commands rate_limit cpufreq: Don't unregister cpufreq cooling on CPU hotplug cpufreq: Honour transition_latency over transition_delay_us cpufreq: Limit resolving a frequency to policy min/max cpufreq: amd-pstate: adjust min/max limit perf cpufreq: Remove references to 10ms min sampling rate cpufreq: intel_pstate: Update default EPPs for Meteor Lake cpufreq: intel_pstate: Allow model specific EPPs cpufreq: qcom-hw: add CONFIG_COMMON_CLK dependency cpufreq: dt-platdev: block SDM670 in cpufreq-dt-platdev cpufreq: intel_pstate: remove cpudata::prev_cummulative_iowait cpufreq: Change default transition delay to 2ms cpufreq: amd-pstate: Fix min_perf assignment in amd_pstate_adjust_perf() Documentation: PM: amd-pstate: Fix section title underline Documentation: introduce amd-pstate preferrd core mode kernel command line options Documentation: amd-pstate: introduce amd-pstate preferred core cpufreq: amd-pstate: Update amd-pstate preferred core ranking dynamically ACPI: cpufreq: Add highest perf change notification ...
2024-03-11Merge branch 'pm-sleep'Rafael J. Wysocki1-0/+11
Merge changes related to system-wide power management for 6.9-rc1: - Fix and clean up system suspend statistics collection (Rafael Wysocki). - Simplify device suspend and resume handling in the power management core code (Rafael Wysocki). - Add support for LZ4 compression algorithm to the hibernation image creation and loading code (Nikhil V). - Fix PCI hibernation support description (Yiwei Lin). - Make hibernation take set_memory_ro() return values into account as appropriate (Christophe Leroy). - Set mem_sleep_current during kernel command line setup to avoid an ordering issue with handling it (Maulik Shah). - Fix wake IRQs handling when pm_runtime_force_suspend() is used as a driver's system suspend callback (Qingliang Li). * pm-sleep: (21 commits) PM: sleep: wakeirq: fix wake irq warning in system suspend PM: suspend: Set mem_sleep_current during kernel command line setup PM: hibernate: Don't ignore return from set_memory_ro() PM: hibernate: Support to select compression algorithm Documentation: PM: Fix PCI hibernation support description PM: hibernate: Add support for LZ4 compression for hibernation PM: hibernate: Move to crypto APIs for LZO compression PM: hibernate: Rename lzo* to make it generic PM: sleep: Call dpm_async_fn() directly in each suspend phase PM: sleep: Move devices to new lists earlier in each suspend phase PM: sleep: Move some assignments from under a lock PM: sleep: stats: Log errors right after running suspend callbacks PM: sleep: stats: Use locking in dpm_save_failed_dev() PM: sleep: stats: Call dpm_save_failed_step() at most once per phase PM: sleep: stats: Define suspend_stats next to the code using it PM: sleep: stats: Use unsigned int for success and failure counters PM: sleep: stats: Use an array of step failure counters PM: sleep: stats: Use array of suspend step names PM: sleep: Relocate two device PM core functions PM: sleep: Simplify dpm_suspended_list walk in dpm_resume() ...
2024-03-08dm vdo: document minimum metadata size requirementsMatthew Sakai1-0/+11
Signed-off-by: Matthew Sakai <msakai@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-03-07docs: verify/bisect: fixes, finetuning, and support for ArchThorsten Leemhuis1-51/+84
Assorted changes for the recently added document. Improvements: * Add instructions for installing required software on Arch Linux. Fixes: * Move a 'git remote add -t master stable [...]' from a totally wrong to the right place. * Fix two anchors. * Add two required packages to the openSUSE install instructions. Fine tuning: * Improve the reference section about downloading Linux mainline sources to make it more obvious that those are alternatives. * Include the full instructions for git bundles to ensure the remote gets the right name; that way the text also works stand alone. * Install ncurses and qt headers for use of menuconfig and xconfig by default, but tell users that they are free to omit them. * Mention ahead of time which version number are meant as example in commands used during the step-by-step guide. * Mention that 'kernel-install remove' might do a incomplete job. Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <6592c9ef4244faa484b4113f088dbc1beca61015.1709716794.git.linux@leemhuis.info>
2024-03-04dm vdo: document log_level parameterKen Raeburn1-0/+7
Signed-off-by: Ken Raeburn <raeburn@redhat.com> Signed-off-by: Matthew Sakai <msakai@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-03-03docs: new text on bisecting which also covers bug validationThorsten Leemhuis2-0/+1920
Add a second document on bisecting regressions explaining the whole process from beginning to end -- while also describing how to validate if a problem is still present in mainline. This "two in one" approach is possible, as checking whenever a bug is in mainline is one of the first steps before performing a bisection anyway and thus needs to be described. Due to this approach the text also works quite nicely in conjunction with Documentation/admin-guide/reporting-issues.rst, as it covers all typical cases where users will need to build a kernel in exactly the same order. The text targets users that normally run kernels from their Linux distributor who might never have compiled their own kernel. This aim is why the first kernel built while following this guide is generated from the latest mainline codebase. This will rule out that the regression (a) was fixed already and (b) is caused by config change a vendor distributor performed; checking mainline will furthermore (c) determine if the issue is something that needs to be reported to the regular developers or the stable team (this is needed even when readers bisect within a stable series). Only then are readers instructed to build their own variant of the 'good' kernel to validate the trimmed .config file created during early in the guide, as performing a bisection with a broken one would be a waste of time. There is a small downside of this order: readers might have to go back to testing mainline, if it turns out there is a problem with their .config. But that should be rare -- and if the regression was already fixed readers might not get to this point anyway. Hence in the end this order should mean that readers built less kernels overall. This sequence allows the text to easily cover the "check if a bug is present in the upstream kernel" case while only making things a tiny bit more complicated. The text tries to prevent readers from running into many mistakes users are known to frequently make. The steps required for this might look superfluous for people that are already familiar with bisections -- but anyone with that knowledge should be able to adapt the instructions to their use-case or will not need this text at all. Style and structure of the text match the one Documentation/admin-guide/quickly-build-trimmed-linux.rst uses. Quite a few paragraphs are even copied from there and not changed at all or only slightly. This will complicate maintenance, as some future changes to one of these documents will have to be replicated in the other. But this is the lesser evil: solutions like "sending readers from one document over to the other" or "extracting the common parts into a separate document" might work in other cases, but would be too confusing here given the topic and the target audience. Signed-off-by: Thorsten Leemhuis <linux@leemhuis.info> [jc: Undo spurious removal of subsection header line] Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <02b084a06de4ad61ac4ecd92b9265d4df4d03d71.1709282441.git.linux@leemhuis.info>
2024-02-29cgroup/cpuset: Mark memory_spread_slab as obsoleteXiongwei Song1-1/+1
We've removed the SLAB allocator, cpuset_do_slab_mem_spread() and SLAB_MEM_SPREAD, memory_spread_slab is a no-op now. We can mark memory_spread_slab as obsolete in case someone still wants to use it after cpuset_do_slab_mem_spread() removed. For more details, please check [1]. [1] https://lore.kernel.org/lkml/32bc1403-49da-445a-8c00-9686a3b0d6a3@redhat.com/T/#m8e292e21b00f95a4bb8086371fa7387fa4ea8f60 tj: Description and cosmetic updates. Signed-off-by: Xiongwei Song <xiongwei.song@windriver.com> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-02-28net: make SK_MEMORY_PCPU_RESERV tunableAdam Li1-0/+5
This patch adds /proc/sys/net/core/mem_pcpu_rsv sysctl file, to make SK_MEMORY_PCPU_RESERV tunable. Commit 3cd3399dd7a8 ("net: implement per-cpu reserves for memory_allocated") introduced per-cpu forward alloc cache: "Implement a per-cpu cache of +1/-1 MB, to reduce number of changes to sk->sk_prot->memory_allocated, which would otherwise be cause of false sharing." sk_prot->memory_allocated points to global atomic variable: atomic_long_t tcp_memory_allocated ____cacheline_aligned_in_smp; If increasing the per-cpu cache size from 1MB to e.g. 16MB, changes to sk->sk_prot->memory_allocated can be further reduced. Performance may be improved on system with many cores. Signed-off-by: Adam Li <adamli@os.amperecomputing.com> Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-27Merge branches 'rcu-doc.2024.02.14a', 'rcu-nocb.2024.02.14a', ↵Boqun Feng1-0/+5
'rcu-exp.2024.02.14a', 'rcu-tasks.2024.02.26a' and 'rcu-misc.2024.02.14a' into rcu.2024.02.26a
2024-02-22PM: hibernate: Support to select compression algorithmNikhil V1-0/+11
Currently the default compression algorithm is selected based on compile time options. Introduce a module parameter "hibernate.compressor" to override this behaviour. Different compression algorithms have different characteristics and hibernation may benefit when it uses any of these algorithms, especially when a secondary algorithm(LZ4) offers better decompression speeds over a default algorithm(LZO), which in turn reduces hibernation image restore time. Users can override the default algorithm in two ways: 1) Passing "hibernate.compressor" as kernel command line parameter. Usage: LZO: hibernate.compressor=lzo LZ4: hibernate.compressor=lz4 2) Specifying the algorithm at runtime. Usage: LZO: echo lzo > /sys/module/hibernate/parameters/compressor LZ4: echo lz4 > /sys/module/hibernate/parameters/compressor Currently LZO and LZ4 are the supported algorithms. LZO is the default compression algorithm used with hibernation. Signed-off-by: Nikhil V <quic_nprakash@quicinc.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-22workqueue: Control intensive warning threshold through cmdlineXuewen Yan1-0/+9
When CONFIG_WQ_CPU_INTENSIVE_REPORT is set, the kernel will report the work functions which violate the intensive_threshold_us repeatedly. And now, only when the violate times exceed 4 and is a power of 2, the kernel warning could be triggered. However, sometimes, even if a long work execution time occurs only once, it may cause other work to be delayed for a long time. This may also cause some problems sometimes. In order to freely control the threshold of warninging, a boot argument is added so that the user can control the warning threshold to be printed. At the same time, keep the exponential backoff to prevent reporting too much. By default, the warning threshold is 4. tj: Updated kernel-parameters.txt description. Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-02-21docs: Correct formatting of title in admin-guide/index.rstCarlos Bilbao1-0/+1
Adjust the title of "The Linux kernel user's and administrator's guide" to adhere to the expected reStructuredText (rst) formatting, using double equal signs for the main header. Signed-off-by: Carlos Bilbao <carlos.bilbao@amd.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240109155643.3489369-2-carlos.bilbao@amd.com
2024-02-21clocksource: Scale the watchdog read retries automaticallyFeng Tang1-6/+0
On a 8-socket server the TSC is wrongly marked as 'unstable' and disabled during boot time on about one out of 120 boot attempts: clocksource: timekeeping watchdog on CPU227: wd-tsc-wd excessive read-back delay of 153560ns vs. limit of 125000ns, wd-wd read-back delay only 11440ns, attempt 3, marking tsc unstable tsc: Marking TSC unstable due to clocksource watchdog TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'. sched_clock: Marking unstable (119294969739, 159204297)<-(125446229205, -5992055152) clocksource: Checking clocksource tsc synchronization from CPU 319 to CPUs 0,99,136,180,210,542,601,896. clocksource: Switched to clocksource hpet The reason is that for platform with a large number of CPUs, there are sporadic big or huge read latencies while reading the watchog/clocksource during boot or when system is under stress work load, and the frequency and maximum value of the latency goes up with the number of online CPUs. The cCurrent code already has logic to detect and filter such high latency case by reading the watchdog twice and checking the two deltas. Due to the randomness of the latency, there is a low probabilty that the first delta (latency) is big, but the second delta is small and looks valid. The watchdog code retries the readouts by default twice, which is not necessarily sufficient for systems with a large number of CPUs. There is a command line parameter 'max_cswd_read_retries' which allows to increase the number of retries, but that's not user friendly as it needs to be tweaked per system. As the number of required retries is proportional to the number of online CPUs, this parameter can be calculated at runtime. Scale and enlarge the number of retries according to the number of online CPUs and remove the command line parameter completely. [ tglx: Massaged change log and comments ] Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jin Wang <jin1.wang@intel.com> Tested-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Waiman Long <longman@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20240221060859.1027450-1-feng.tang@intel.com
2024-02-20dm vdo: add vio life cycle details to design docMatthew Sakai1-228/+446
Add more documentation details for most aspects of the data_vio read and write processes. Also correct a few minor errors and rewrite some text for clarity. Signed-off-by: Matthew Sakai <msakai@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-02-20dm vdo: add vdo documentation to device-mapper indexMatthew Sakai1-0/+2
Signed-off-by: Matthew Sakai <msakai@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-02-20dm: add documentation for dm-vdo targetMatthew Sakai2-0/+803
This adds the admin-guide documentation for dm-vdo. vdo.rst is the guide to using dm-vdo. vdo-design is an overview of the design of dm-vdo. Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net> Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net> Signed-off-by: Matthew Sakai <msakai@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-02-16x86/cpu: Detect real BSP on crash kernelsThomas Gleixner2-14/+2
When a kdump kernel is started from a crashing CPU then there is no guarantee that this CPU is the real boot CPU (BSP). If the kdump kernel tries to online the BSP then the INIT sequence will reset the machine. There is a command line option to prevent this, but in case of nested kdump kernels this is wrong. But that command line option is not required at all because the real BSP is enumerated as the first CPU by firmware. Support for the only known system which was different (Voyager) got removed long ago. Detect whether the boot CPU APIC ID is the first APIC ID enumerated by the firmware. If the first APIC ID enumerated is not matching the boot CPU APIC ID then skip registering it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210252.348542071@linutronix.de
2024-02-15docs: admin-guide: Update bootloader and installation instructionsHunter Chasens1-24/+45
Updates the bootloader and installation instructions in admin-guide/README.rst to align with modern practices. Details of Changes: - Added guidance on using EFISTUB for UEFI/EFI systems. - Noted that LILO is no longer in active development and provides alternatives. - Kept LILO instructions but marked as Legacy LILO Instructions. Suggest removal in future patch. Signed-off-by: Hunter Chasens <hunter.chasens18@ncf.edu> Signed-off-by: Jonathan Corbet <corbet@lwn.net> [jc: repaired added whitespace warnings] Link: https://lore.kernel.org/r/20240207171007.45405-1-hunter.chasens18@ncf.edu
2024-02-14Documentation: Move RAS section to admin-guideBorislav Petkov (AMD)5-4/+60
This is where this stuff should be. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/87a5pes8jy.fsf@meer.lwn.net
2024-02-14rcu: Provide a boot time parameter to control lazy RCUQais Yousef1-0/+5
To allow more flexible arrangements while still provide a single kernel for distros, provide a boot time parameter to enable/disable lazy RCU. Specify: rcutree.enable_rcu_lazy=[y|1|n|0] Which also requires rcu_nocbs=all at boot time to enable/disable lazy RCU. To disable it by default at build time when CONFIG_RCU_LAZY=y, the new CONFIG_RCU_LAZY_DEFAULT_OFF can be used. Signed-off-by: Qais Yousef (Google) <qyousef@layalina.io> Tested-by: Andrea Righi <andrea.righi@canonical.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2024-02-14doc: Add EARLY flag to early-parsed kernel boot parametersPaul E. McKenney2-235/+250
Kernel boot parameters declared with early_param() are parsed before embedded parameters are extracted from initrd, and early_param() parameters are not helpful when embedded in initrd. Therefore, mark early_param() kernel boot parameters with "EARLY" in kernel-parameters.txt. The following early_param() calls declare kernel boot parameters that are undocumented: early_param("atmel.pm_modes", at91_pm_modes_select); early_param("mem_fclk_21285", early_fclk); early_param("ecc", early_ecc); early_param("cachepolicy", early_cachepolicy); early_param("nodebugmon", early_debug_disable); early_param("kfence.sample_interval", parse_kfence_early_init); early_param("additional_cpus", setup_additional_cpus); early_param("stram_pool", atari_stram_setup); early_param("disable_octeon_edac", disable_octeon_edac); early_param("rd_start", rd_start_early); early_param("rd_size", rd_size_early); early_param("coherentio", setcoherentio); early_param("nocoherentio", setnocoherentio); early_param("fadump", early_fadump_param); early_param("fadump_reserve_mem", early_fadump_reserve_mem); early_param("no_stf_barrier", handle_no_stf_barrier); early_param("no_rfi_flush", handle_no_rfi_flush); early_param("smt-enabled", early_smt_enabled); early_param("ppc_pci_reset_phbs", pci_reset_phbs_setup); early_param("ps3fb", early_parse_ps3fb); early_param("ps3flash", early_parse_ps3flash); early_param("novx", disable_vector_extension); early_param("nobp", nobp_setup_early); early_param("nospec", nospec_setup_early); early_param("possible_cpus", _setup_possible_cpus); early_param("stp", early_parse_stp); early_param("nopfault", nopfault); early_param("nmi_mode", nmi_mode_setup); early_param("sh_mv", early_parse_mv); early_param("pmb", early_pmb); early_param("hvirq", early_hvirq_major); early_param("cfi", cfi_parse_cmdline); early_param("disableapic", setup_disableapic); early_param("noapictimer", parse_disable_apic_timer); early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid); early_param("uv_memblksize", parse_mem_block_size); early_param("retbleed", retbleed_parse_cmdline); early_param("no-kvmclock-vsyscall", parse_no_kvmclock_vsyscall); early_param("update_mptable", update_mptable_setup); early_param("alloc_mptable", parse_alloc_mptable_opt); early_param("possible_cpus", _setup_possible_cpus); early_param("lsmsi", early_parse_ls_scfg_msi); early_param("nokgdbroundup", opt_nokgdbroundup); early_param("kgdbcon", opt_kgdb_con); early_param("kasan", early_kasan_flag); early_param("kasan.mode", early_kasan_mode); early_param("kasan.vmalloc", early_kasan_flag_vmalloc); early_param("kasan.page_alloc.sample", early_kasan_flag_page_alloc_sample); early_param("kasan.page_alloc.sample.order", early_kasan_flag_page_alloc_sample_order); early_param("kasan.fault", early_kasan_fault); early_param("kasan.stacktrace", early_kasan_flag_stacktrace); early_param("kasan.stack_ring_size", early_kasan_flag_stack_ring_size); early_param("accept_memory", accept_memory_parse); early_param("page_table_check", early_page_table_check_param); sh_early_platform_init("earlytimer", &sh_cmt_device_driver); early_param_on_off("gbpages", "nogbpages", direct_gbpages, CONFIG_X86_DIRECT_GBPAGES); These are not necessarily bugs, given that some kernel boot parameters are intended for deep debugging rather than general use. This work does not cover all of the kernel boot parameters declared using cmdline_find_option() and cmdline_find_option_bool(). If these are in fact guaranteed to be early (which appears to be the case), they can be added in a later version of this patch. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Petr Malat <oss@malat.biz> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: <linux-doc@vger.kernel.org> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2024-02-14Merge branch 'x86/bugs' into x86/core, to pick up pending changes before ↵Ingo Molnar2-6/+6
dependent patches Merge in pending alternatives patching infrastructure changes, before applying more patches. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-02-12Documentation: PM: amd-pstate: Fix section title underlineMeng Li1-1/+1
Title under line too short Signed-off-by: Meng Li <li.meng@amd.com> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-12Merge tag 'v6.8-rc4' into gpio/for-nextBartosz Golaszewski2-15/+6
Linux 6.8-rc4 Pulling this for a bugfix upstream with which the gpio/for-next branch conflicts.
2024-02-05Documentation: admin-guide: tainted-kernels.rst: Add missing article and commaThorsten Blum1-2/+2
- Add missing article "the" - s/above example/example above/ - Add missing comma after introductory clause to improve readability Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240205132409.1957-1-thorsten.blum@toblux.com
2024-02-05docs: Document possible_cpus parameterGuilherme G. Piccoli1-0/+5
The number of possible CPUs is set be kernel in early boot time through some discovery mechanisms, like ACPI in x86. We have a parameter both in x86 and S390 to override that - there are some cases of BIOSes exposing more possible CPUs than the available ones, so this parameter is a good testing mechanism, but for some reason wasn't mentioned so far in the kernel parameters guide - let's fix that. Cc: Changwoo Min <changwoo@igalia.com> Signed-off-by: "Guilherme G. Piccoli" <gpiccoli@igalia.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240203152208.1461293-1-gpiccoli@igalia.com
2024-02-03x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULTBorislav Petkov (AMD)1-3/+1
It was meant well at the time but nothing's using it so get rid of it. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20240202163510.GDZb0Zvj8qOndvFOiZ@fat_crate.local
2024-01-31Documentation: introduce amd-pstate preferrd core mode kernel command line ↵Meng Li1-0/+5
options amd-pstate driver support enable/disable preferred core. Default enabled on platforms supporting amd-pstate preferred core. Disable amd-pstate preferred core with "amd_prefcore=disable" added to the kernel command line. Signed-off-by: Meng Li <li.meng@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Perry Yuan <perry.yuan@amd.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-31Documentation: amd-pstate: introduce amd-pstate preferred coreMeng Li1-2/+57
Introduce amd-pstate preferred core. check preferred core state set by the kernel parameter: $ cat /sys/devices/system/cpu/amd-pstate/prefcore Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Reviewed-by: Wyes Karny <wyes.karny@amd.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reviewed-by: Huang Rui <ray.huang@amd.com> Reviewed-by: Perry Yuan <perry.yuan@amd.com> Signed-off-by: Meng Li <li.meng@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-01-30x86/fred: Add a fred= cmdline paramXin Li1-0/+6
Let command line option "fred" accept multiple options to make it easier to tweak its behavior. Currently, two options 'on' and 'off' are allowed, and the default behavior is to disable FRED. To enable FRED, append "fred=on" to the kernel command line. [ bp: Use cpu_feature_enabled(), touch ups. ] Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-9-xin3.li@intel.com
2024-01-24docs: admin-guide: remove obsolete advice related to SLAB allocatorLukas Bulwahn1-10/+6
Commit 1db9d06aaa55 ("mm/slab: remove CONFIG_SLAB from all Kconfig and Makefile") removes the config SLAB and makes the SLUB allocator the only default allocator in the kernel. Hence, the advice on reducing OS jitter due to kworker kernel threads to build with CONFIG_SLUB instead of CONFIG_SLAB is obsolete. Remove the obsolete advice to build with SLUB instead of SLAB. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231130095515.21586-1-lukas.bulwahn@gmail.com
2024-01-24doc: admin-guide/kernel-parameters: remove useless commentVegard Nossum1-5/+0
This comment about DRM drivers has been there since the first git commit. It simply doesn't belong in kernel-parameters; remove it. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240111085220.3693059-1-vegard.nossum@oracle.com