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2024-02-22Docs/mm/damon: move the list of DAMOS actions to design docSeongJae Park
DAMOS operation actions are explained nearly twice on the DAMON usage document, once for the sysfs interface, and then again for the debugfs interface. Duplication is bad. Also it would better to keep this kind of concept level details in design document and keep the usage document small and focus on only the usage. Move the list to design document and update usage document to reference it. Link: https://lkml.kernel.org/r/20240217005842.87348-3-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22PM: hibernate: Support to select compression algorithmNikhil V
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>
2024-02-22mm/mempolicy: introduce MPOL_WEIGHTED_INTERLEAVE for weighted interleavingGregory Price
When a system has multiple NUMA nodes and it becomes bandwidth hungry, using the current MPOL_INTERLEAVE could be an wise option. However, if those NUMA nodes consist of different types of memory such as socket-attached DRAM and CXL/PCIe attached DRAM, the round-robin based interleave policy does not optimally distribute data to make use of their different bandwidth characteristics. Instead, interleave is more effective when the allocation policy follows each NUMA nodes' bandwidth weight rather than a simple 1:1 distribution. This patch introduces a new memory policy, MPOL_WEIGHTED_INTERLEAVE, enabling weighted interleave between NUMA nodes. Weighted interleave allows for proportional distribution of memory across multiple numa nodes, preferably apportioned to match the bandwidth of each node. For example, if a system has 1 CPU node (0), and 2 memory nodes (0,1), with bandwidth of (100GB/s, 50GB/s) respectively, the appropriate weight distribution is (2:1). Weights for each node can be assigned via the new sysfs extension: /sys/kernel/mm/mempolicy/weighted_interleave/ For now, the default value of all nodes will be `1`, which matches the behavior of standard 1:1 round-robin interleave. An extension will be added in the future to allow default values to be registered at kernel and device bringup time. The policy allocates a number of pages equal to the set weights. For example, if the weights are (2,1), then 2 pages will be allocated on node0 for every 1 page allocated on node1. The new flag MPOL_WEIGHTED_INTERLEAVE can be used in set_mempolicy(2) and mbind(2). Some high level notes about the pieces of weighted interleave: current->il_prev: Tracks the node previously allocated from. current->il_weight: The active weight of the current node (current->il_prev) When this reaches 0, current->il_prev is set to the next node and current->il_weight is set to the next weight. weighted_interleave_nodes: Counts the number of allocations as they occur, and applies the weight for the current node. When the weight reaches 0, switch to the next node. Operates only on task->mempolicy. weighted_interleave_nid: Gets the total weight of the nodemask as well as each individual node weight, then calculates the node based on the given index. Operates on VMA policies. bulk_array_weighted_interleave: Gets the total weight of the nodemask as well as each individual node weight, then calculates the number of "interleave rounds" as well as any delta ("partial round"). Calculates the number of pages for each node and allocates them. If a node was scheduled for interleave via interleave_nodes, the current weight will be allocated first. Operates only on the task->mempolicy. One piece of complexity is the interaction between a recent refactor which split the logic to acquire the "ilx" (interleave index) of an allocation and the actually application of the interleave. If a call to alloc_pages_mpol() were made with a weighted-interleave policy and ilx set to NO_INTERLEAVE_INDEX, weighted_interleave_nodes() would operate on a VMA policy - violating the description above. An inspection of all callers of alloc_pages_mpol() shows that all external callers set ilx to `0`, an index value, or will call get_vma_policy() to acquire the ilx. For example, mm/shmem.c may call into alloc_pages_mpol. The call stacks all set (pgoff_t ilx) or end up in `get_vma_policy()`. This enforces the `weighted_interleave_nodes()` and `weighted_interleave_nid()` policy requirements (task/vma respectively). Link: https://lkml.kernel.org/r/20240202170238.90004-4-gregory.price@memverge.com Suggested-by: Hasan Al Maruf <Hasan.Maruf@amd.com> Signed-off-by: Gregory Price <gregory.price@memverge.com> Co-developed-by: Rakie Kim <rakie.kim@sk.com> Signed-off-by: Rakie Kim <rakie.kim@sk.com> Co-developed-by: Honggyu Kim <honggyu.kim@sk.com> Signed-off-by: Honggyu Kim <honggyu.kim@sk.com> Co-developed-by: Hyeongtak Ji <hyeongtak.ji@sk.com> Signed-off-by: Hyeongtak Ji <hyeongtak.ji@sk.com> Co-developed-by: Srinivasulu Thanneeru <sthanneeru.opensrc@micron.com> Signed-off-by: Srinivasulu Thanneeru <sthanneeru.opensrc@micron.com> Co-developed-by: Ravi Jonnalagadda <ravis.opensrc@micron.com> Signed-off-by: Ravi Jonnalagadda <ravis.opensrc@micron.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22Docs/admin-guide/mm/damon/usage: update for monitor_on renamingSeongJae Park
Update DAMON debugfs interface sections on the usage document to reflect the fact that 'monitor_on' file has renamed to 'monitor_on_DEPRECATED'. Link: https://lkml.kernel.org/r/20240130013549.89538-9-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Alex Shi <alexs@kernel.org> Cc: Hu Haowen <2023002089@link.tyut.edu.cn> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yanteng Si <siyanteng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22Docs/admin-guide/mm/damon/usage: document 'DEPRECATED' file of DAMON debugfs ↵SeongJae Park
interface Document the newly added DAMON debugfs interface deprecation notice file on the usage document. Link: https://lkml.kernel.org/r/20240130013549.89538-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Alex Shi <alexs@kernel.org> Cc: Hu Haowen <2023002089@link.tyut.edu.cn> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yanteng Si <siyanteng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22Docs/admin-guide/mm/damon/usage: use sysfs interface for tracepoints exampleSeongJae Park
Patch series "mm/damon: make DAMON debugfs interface deprecation unignorable". DAMON debugfs interface is deprecated in February 2023, by commit 5445fcbc4cda ("Docs/admin-guide/mm/damon/usage: add DAMON debugfs interface deprecation notice"). Make the fact unable to be easily ignored by removing an example usage from the document (patch 1), renaming the config (patch 2), adding a deprecation notice file to the debugfs directory (patches 3-5), and renaming the debugfs file that essnetial to be used for real use of DAMON (patches 6-9). This patch (of 9): DAMON tracepoints example on the DAMON usage document is using DAMON debugfs interface, which is deprecated. Use its alternative, DAMON sysfs interface. Link: https://lkml.kernel.org/r/20240130013549.89538-1-sj@kernel.org Link: https://lkml.kernel.org/r/20240130013549.89538-2-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Alex Shi <alexs@kernel.org> Cc: Hu Haowen <2023002089@link.tyut.edu.cn> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yanteng Si <siyanteng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22workqueue: Control intensive warning threshold through cmdlineXuewen Yan
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 Bilbao
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 Tang
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 Sakai
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 Sakai
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 Sakai
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>
2024-02-16doc: media: visl: Document tpg_verbose parameterDetlev Casanova
Also document stable frames and what it means for testing tools. Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> [hverkuil: add media: prefix to Subject]
2024-02-15x86/cpu: Detect real BSP on crash kernelsThomas Gleixner
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
2024-02-14docs: admin-guide: Update bootloader and installation instructionsHunter Chasens
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)
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 Yousef
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. McKenney
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 Molnar
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 Li
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 Golaszewski
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 Blum
- 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. Piccoli
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
2024-02-05documentation: media: vivid: Modify typo in documentationDorcas Anono Litunya
Correct the default value of node_type vivid parameter to 0xe1d3d. Signed-off-by: Dorcas Anono Litunya <anonolitunya@gmail.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
2024-02-03x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULTBorislav Petkov (AMD)
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 Li
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 Li
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 Li
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
2024-01-24platform/x86: Support for mode FN keyMark Pearson
New Thinkpads have added a 'Mode' Function key that on Windows allows you to choose the active profile (low-power, balanced, performance) Added suppoort for this hotkey (F8), and have it cycle through the options available. Tested on X1 Carbon G12. Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20240120232949.317337-1-mpearson-lenovo@squebb.ca Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2024-01-23docs: admin-guide: remove obsolete advice related to SLAB allocatorLukas Bulwahn
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
2024-01-23doc: admin-guide/kernel-parameters: remove useless commentVegard Nossum
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
2024-01-23docs: cgroup-v1: add missing code-block tagsXinyu Li
Hugetlb.rst lacks two code-block tags, causing a formatting issue. Signed-off-by: Xinyu Li <lixinyu20s@ict.ac.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2024-01-23Documentation/kernel-parameters: Add spec_rstack_overflow to mitigations=offBorislav Petkov (AMD)
mitigations=off disables the SRSO mitigation too. Add it to the list. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20240118163600.17857-1-bp@alien8.de
2024-01-22Documentation: gpio: move gpio-mockup into obsolete sectionKent Gibson
The gpio-mockup has been obsoleted by the gpio-sim, so relocate its documentation into the obsolete section of the admin-guide book. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22Documentation: gpio: document gpio-mockup as obsoleted by gpio-simKent Gibson
Update the gpio-mockup documentation to note that is has been obsoleted by the gpio-sim. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22Documentation: gpio: capitalize GPIO in index titleKent Gibson
Capitalise the title of the GPIO documentation page to match other subsystems. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22Documentation: gpio: add chardev v1 userspace API documentationKent Gibson
Add documentation for v1 of the GPIO character device userspace API to the obsolete section of both the admin-guide and userspace-api books. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22Documentation: gpio: move sysfs into an obsolete sectionKent Gibson
The GPIO sysfs API is long obsolete, so highlight this even further by moving it into an obsolete APIs section in both the admin-guide and userspace-api books. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22Documentation: gpio: add chardev userspace API documentationKent Gibson
Add documentation for the GPIO character device userspace API. Added to the userspace-api book, but also provide a link from the admin-guide book, as historically the GPIO documentation has been there. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-01-22mm/slub: unify all sl[au]b parameters with "slab_$param"Xiongwei Song
Since the SLAB allocator has been removed, so we can clean up the sl[au]b_$params. With only one slab allocator left, it's better to use the generic "slab" term instead of "slub" which is an implementation detail, which is pointed out by Vlastimil Babka. For more information please see [1]. Hence, we are going to use "slab_$param" as the primary prefix. This patch is changing the following slab parameters - slub_max_order - slub_min_order - slub_min_objects - slub_debug to - slab_max_order - slab_min_order - slab_min_objects - slab_debug as the primary slab parameters for all references of them in docs and comments. But this patch won't change variables and functions inside slub as we will have wider slub/slab change. Meanwhile, "slub_$params" can also be passed by command line, which is to keep backward compatibility. Also mark all "slub_$params" as legacy. Remove the separate descriptions for slub_[no]merge, append legacy tip for them at the end of descriptions of slab_[no]merge. [1] https://lore.kernel.org/linux-mm/7512b350-4317-21a0-fab3-4101bc4d8f7a@suse.cz/ Signed-off-by: Xiongwei Song <xiongwei.song@windriver.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2024-01-22Documentation: kernel-parameters: remove noaliencacheXiongwei Song
Since slab allocator has already been removed. There is no users of the noaliencache parameter, so let's remove it. Suggested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Xiongwei Song <xiongwei.song@windriver.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2024-01-20Merge tag 'v6.8-rc-part2-smb-client' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull smb client updates from Steve French: "Various smb client fixes, including multichannel and for SMB3.1.1 POSIX extensions: - debugging improvement (display start time for stats) - two reparse point handling fixes - various multichannel improvements and fixes - SMB3.1.1 POSIX extensions open/create parsing fix - retry (reconnect) improvement including new retrans mount parm, and handling of two additional return codes that need to be retried on - two minor cleanup patches and another to remove duplicate query info code - two documentation cleanup, and one reviewer email correction" * tag 'v6.8-rc-part2-smb-client' of git://git.samba.org/sfrench/cifs-2.6: cifs: update iface_last_update on each query-and-update cifs: handle servers that still advertise multichannel after disabling cifs: new mount option called retrans cifs: reschedule periodic query for server interfaces smb: client: don't clobber ->i_rdev from cached reparse points smb: client: get rid of smb311_posix_query_path_info() smb: client: parse owner/group when creating reparse points smb: client: fix parsing of SMB3.1.1 POSIX create context cifs: update known bugs mentioned in kernel docs for cifs cifs: new nt status codes from MS-SMB2 cifs: pick channel for tcon and tdis cifs: open_cached_dir should not rely on primary channel smb3: minor documentation updates Update MAINTAINERS email address cifs: minor comment cleanup smb3: show beginning time for per share stats cifs: remove redundant variable tcon_exist
2024-01-19Merge tag 'loongarch-6.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Raise minimum clang version to 18.0.0 - Enable initial Rust support for LoongArch - Add built-in dtb support for LoongArch - Use generic interface to support crashkernel=X,[high,low] - Some bug fixes and other small changes - Update the default config file. * tag 'loongarch-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (22 commits) MAINTAINERS: Add BPF JIT for LOONGARCH entry LoongArch: Update Loongson-3 default config file LoongArch: BPF: Prevent out-of-bounds memory access LoongArch: BPF: Support 64-bit pointers to kfuncs LoongArch: Fix definition of ftrace_regs_set_instruction_pointer() LoongArch: Use generic interface to support crashkernel=X,[high,low] LoongArch: Fix and simplify fcsr initialization on execve() LoongArch: Let cores_io_master cover the largest NR_CPUS LoongArch: Change SHMLBA from SZ_64K to PAGE_SIZE LoongArch: Add a missing call to efi_esrt_init() LoongArch: Parsing CPU-related information from DTS LoongArch: dts: DeviceTree for Loongson-2K2000 LoongArch: dts: DeviceTree for Loongson-2K1000 LoongArch: dts: DeviceTree for Loongson-2K0500 LoongArch: Allow device trees be built into the kernel dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for interrupt-names dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for reg-names dt-bindings: loongarch: Add Loongson SoC boards compatibles dt-bindings: loongarch: Add CPU bindings for LoongArch LoongArch: Enable initial Rust support ...
2024-01-19cifs: update known bugs mentioned in kernel docs for cifsSteve French
Remove bugs that have been addressed and add link to xfstest results wiki. Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-18smb3: minor documentation updatesSteve French
Update the usage documentation to include some missing configuration options. Update the todo list documentation for cifs.ko Reviewed-by: Bharath SM <bharathsm@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-18Merge tag 'usb-6.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB / Thunderbolt updates from Greg KH: "Here is the big set of USB and Thunderbolt changes for 6.8-rc1. Included in here are the following: - Thunderbolt subsystem and driver updates for USB 4 hardware and issues reported by real devices - xhci driver updates - dwc3 driver updates - uvc_video gadget driver updates - typec driver updates - gadget string functions cleaned up - other small changes All of these have been in the linux-next tree for a while with no reported issues" * tag 'usb-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (169 commits) usb: typec: tipd: fix use of device-specific init function usb: typec: tipd: Separate reset for TPS6598x usb: mon: Fix atomicity violation in mon_bin_vma_fault usb: gadget: uvc: Remove nested locking usb: gadget: uvc: Fix use are free during STREAMOFF usb: typec: class: fix typec_altmode_put_partner to put plugs dt-bindings: usb: dwc3: Limit num-hc-interrupters definition dt-bindings: usb: xhci: Add num-hc-interrupters definition xhci: add support to allocate several interrupters USB: core: Use device_driver directly in struct usb_driver and usb_device_driver arm64: dts: mediatek: mt8195: Add 'rx-fifo-depth' for cherry usb: xhci-mtk: fix a short packet issue of gen1 isoc-in transfer dt-bindings: usb: mtk-xhci: add a property for Gen1 isoc-in transfer issue arm64: dts: qcom: msm8996: Remove PNoC clock from MSS arm64: dts: qcom: msm8996: Remove AGGRE2 clock from SLPI arm64: dts: qcom: msm8998: Remove AGGRE2 clock from SLPI arm64: dts: qcom: msm8939: Drop RPM bus clocks arm64: dts: qcom: sdm630: Drop RPM bus clocks arm64: dts: qcom: qcs404: Drop RPM bus clocks arm64: dts: qcom: msm8996: Drop RPM bus clocks ...
2024-01-18Merge tag 'tty-6.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial updates from Greg KH: "Here is the big set of tty and serial driver changes for 6.8-rc1. As usual, Jiri has a bunch of refactoring and cleanups for the tty core and drivers in here, along with the usual set of rs485 updates (someday this might work properly...) Along with those, in here are changes for: - sc16is7xx serial driver updates - platform driver removal api updates - amba-pl011 driver updates - tty driver binding updates - other small tty/serial driver updates and changes All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (197 commits) serial: sc16is7xx: refactor EFR lock serial: sc16is7xx: reorder code to remove prototype declarations serial: sc16is7xx: refactor FIFO access functions to increase commonality serial: sc16is7xx: drop unneeded MODULE_ALIAS serial: sc16is7xx: replace hardcoded divisor value with BIT() macro serial: sc16is7xx: add explicit return for some switch default cases serial: sc16is7xx: add macro for max number of UART ports serial: sc16is7xx: add driver name to struct uart_driver serial: sc16is7xx: use i2c_get_match_data() serial: sc16is7xx: use spi_get_device_match_data() serial: sc16is7xx: use DECLARE_BITMAP for sc16is7xx_lines bitfield serial: sc16is7xx: improve do/while loop in sc16is7xx_irq() serial: sc16is7xx: remove obsolete loop in sc16is7xx_port_irq() serial: sc16is7xx: set safe default SPI clock frequency serial: sc16is7xx: add check for unsupported SPI modes during probe serial: sc16is7xx: fix invalid sc16is7xx_lines bitfield in case of probe error serial: 8250_exar: Set missing rs485_supported flag serial: omap: do not override settings for RS485 support serial: core, imx: do not set RS485 enabled if it is not supported serial: core: make sure RS485 cannot be enabled when it is not supported ...
2024-01-18Merge tag 'driver-core-6.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here are the set of driver core and kernfs changes for 6.8-rc1. Nothing major in here this release cycle, just lots of small cleanups and some tweaks on kernfs that in the very end, got reverted and will come back in a safer way next release cycle. Included in here are: - more driver core 'const' cleanups and fixes - fw_devlink=rpm is now the default behavior - kernfs tiny changes to remove some string functions - cpu handling in the driver core is updated to work better on many systems that add topologies and cpus after booting - other minor changes and cleanups All of the cpu handling patches have been acked by the respective maintainers and are coming in here in one series. Everything has been in linux-next for a while with no reported issues" * tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (51 commits) Revert "kernfs: convert kernfs_idr_lock to an irq safe raw spinlock" kernfs: convert kernfs_idr_lock to an irq safe raw spinlock class: fix use-after-free in class_register() PM: clk: make pm_clk_add_notifier() take a const pointer EDAC: constantify the struct bus_type usage kernfs: fix reference to renamed function driver core: device.h: fix Excess kernel-doc description warning driver core: class: fix Excess kernel-doc description warning driver core: mark remaining local bus_type variables as const driver core: container: make container_subsys const driver core: bus: constantify subsys_register() calls driver core: bus: make bus_sort_breadthfirst() take a const pointer kernfs: d_obtain_alias(NULL) will do the right thing... driver core: Better advertise dev_err_probe() kernfs: Convert kernfs_path_from_node_locked() from strlcpy() to strscpy() kernfs: Convert kernfs_name_locked() from strlcpy() to strscpy() kernfs: Convert kernfs_walk_ns() from strlcpy() to strscpy() initramfs: Expose retained initrd as sysfs file fs/kernfs/dir: obey S_ISGID kernel/cgroup: use kernfs_create_dir_ns() ...
2024-01-17Merge tag 'pm-6.8-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "These restore the asynchronous device resume optimization removed by the previous PM merge, make the intel_pstate driver work better on Meteor Lake systems, optimize the PM QoS core code slightly and fix up typos in admin-guide. Specifics: - Restore the system-wide asynchronous device resume optimization removed by a recent concurrency fix (Rafael J. Wysocki) - Make the intel_pstate cpufreq driver allow Meteor Lake systems to run at somewhat higher frequencies (Srinivas Pandruvada) - Make the PM QoS core code use kcalloc() for array allocation (Erick Archer) - Fix two PM-related typos in admin-guide (Erwan Velu)" * tag 'pm-6.8-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM: sleep: Restore asynchronous device resume optimization Documentation: admin-guide: PM: Fix two typos cpufreq: intel_pstate: Update hybrid scaling factor for Meteor Lake PM: QoS: Use kcalloc() instead of kzalloc()
2024-01-17Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "Generic: - Use memdup_array_user() to harden against overflow. - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures. - Clean up Kconfigs that all KVM architectures were selecting - New functionality around "guest_memfd", a new userspace API that creates an anonymous file and returns a file descriptor that refers to it. guest_memfd files are bound to their owning virtual machine, cannot be mapped, read, or written by userspace, and cannot be resized. guest_memfd files do however support PUNCH_HOLE, which can be used to switch a memory area between guest_memfd and regular anonymous memory. - New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify per-page attributes for a given page of guest memory; right now the only attribute is whether the guest expects to access memory via guest_memfd or not, which in Confidential SVMs backed by SEV-SNP, TDX or ARM64 pKVM is checked by firmware or hypervisor that guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in the case of pKVM). x86: - Support for "software-protected VMs" that can use the new guest_memfd and page attributes infrastructure. This is mostly useful for testing, since there is no pKVM-like infrastructure to provide a meaningfully reduced TCB. - Fix a relatively benign off-by-one error when splitting huge pages during CLEAR_DIRTY_LOG. - Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE. - Use more generic lockdep assertions in paths that don't actually care about whether the caller is a reader or a writer. - let Xen guests opt out of having PV clock reported as "based on a stable TSC", because some of them don't expect the "TSC stable" bit (added to the pvclock ABI by KVM, but never set by Xen) to be set. - Revert a bogus, made-up nested SVM consistency check for TLB_CONTROL. - Advertise flush-by-ASID support for nSVM unconditionally, as KVM always flushes on nested transitions, i.e. always satisfies flush requests. This allows running bleeding edge versions of VMware Workstation on top of KVM. - Sanity check that the CPU supports flush-by-ASID when enabling SEV support. - On AMD machines with vNMI, always rely on hardware instead of intercepting IRET in some cases to detect unmasking of NMIs - Support for virtualizing Linear Address Masking (LAM) - Fix a variety of vPMU bugs where KVM fail to stop/reset counters and other state prior to refreshing the vPMU model. - Fix a double-overflow PMU bug by tracking emulated counter events using a dedicated field instead of snapshotting the "previous" counter. If the hardware PMC count triggers overflow that is recognized in the same VM-Exit that KVM manually bumps an event count, KVM would pend PMIs for both the hardware-triggered overflow and for KVM-triggered overflow. - Turn off KVM_WERROR by default for all configs so that it's not inadvertantly enabled by non-KVM developers, which can be problematic for subsystems that require no regressions for W=1 builds. - Advertise all of the host-supported CPUID bits that enumerate IA32_SPEC_CTRL "features". - Don't force a masterclock update when a vCPU synchronizes to the current TSC generation, as updating the masterclock can cause kvmclock's time to "jump" unexpectedly, e.g. when userspace hotplugs a pre-created vCPU. - Use RIP-relative address to read kvm_rebooting in the VM-Enter fault paths, partly as a super minor optimization, but mostly to make KVM play nice with position independent executable builds. - Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on CONFIG_HYPERV as a minor optimization, and to self-document the code. - Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation" at build time. ARM64: - LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base granule sizes. Branch shared with the arm64 tree. - Large Fine-Grained Trap rework, bringing some sanity to the feature, although there is more to come. This comes with a prefix branch shared with the arm64 tree. - Some additional Nested Virtualization groundwork, mostly introducing the NV2 VNCR support and retargetting the NV support to that version of the architecture. - A small set of vgic fixes and associated cleanups. Loongarch: - Optimization for memslot hugepage checking - Cleanup and fix some HW/SW timer issues - Add LSX/LASX (128bit/256bit SIMD) support RISC-V: - KVM_GET_REG_LIST improvement for vector registers - Generate ISA extension reg_list using macros in get-reg-list selftest - Support for reporting steal time along with selftest s390: - Bugfixes Selftests: - Fix an annoying goof where the NX hugepage test prints out garbage instead of the magic token needed to run the test. - Fix build errors when a header is delete/moved due to a missing flag in the Makefile. - Detect if KVM bugged/killed a selftest's VM and print out a helpful message instead of complaining that a random ioctl() failed. - Annotate the guest printf/assert helpers with __printf(), and fix the various bugs that were lurking due to lack of said annotation" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits) x86/kvm: Do not try to disable kvmclock if it was not enabled KVM: x86: add missing "depends on KVM" KVM: fix direction of dependency on MMU notifiers KVM: introduce CONFIG_KVM_COMMON KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache RISC-V: KVM: selftests: Add get-reg-list test for STA registers RISC-V: KVM: selftests: Add steal_time test support RISC-V: KVM: selftests: Add guest_sbi_probe_extension RISC-V: KVM: selftests: Move sbi_ecall to processor.c RISC-V: KVM: Implement SBI STA extension RISC-V: KVM: Add support for SBI STA registers RISC-V: KVM: Add support for SBI extension registers RISC-V: KVM: Add SBI STA info to vcpu_arch RISC-V: KVM: Add steal-update vcpu request RISC-V: KVM: Add SBI STA extension skeleton RISC-V: paravirt: Implement steal-time support RISC-V: Add SBI STA extension definitions RISC-V: paravirt: Add skeleton for pv-time support RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr() ...