diff options
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/cgroup-v1/cpusets.rst | 2 | ||||
| -rw-r--r-- | Documentation/admin-guide/device-mapper/dm-flakey.rst | 4 | ||||
| -rw-r--r-- | Documentation/admin-guide/ext4.rst | 3 | ||||
| -rw-r--r-- | Documentation/admin-guide/kdump/vmcoreinfo.rst | 6 | ||||
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 93 | ||||
| -rw-r--r-- | Documentation/admin-guide/mm/ksm.rst | 5 | ||||
| -rw-r--r-- | Documentation/admin-guide/mm/userfaultfd.rst | 25 | ||||
| -rw-r--r-- | Documentation/admin-guide/pm/amd-pstate.rst | 31 | ||||
| -rw-r--r-- | Documentation/admin-guide/serial-console.rst | 36 | ||||
| -rw-r--r-- | Documentation/admin-guide/xfs.rst | 7 |
10 files changed, 154 insertions, 58 deletions
diff --git a/Documentation/admin-guide/cgroup-v1/cpusets.rst b/Documentation/admin-guide/cgroup-v1/cpusets.rst index 5d844ed4df69..ae646d621a8a 100644 --- a/Documentation/admin-guide/cgroup-v1/cpusets.rst +++ b/Documentation/admin-guide/cgroup-v1/cpusets.rst @@ -719,7 +719,7 @@ There are ways to query or modify cpusets: cat, rmdir commands from the shell, or their equivalent from C. - via the C library libcpuset. - via the C library libcgroup. - (http://sourceforge.net/projects/libcg/) + (https://github.com/libcgroup/libcgroup/) - via the python application cset. (http://code.google.com/p/cpuset/) diff --git a/Documentation/admin-guide/device-mapper/dm-flakey.rst b/Documentation/admin-guide/device-mapper/dm-flakey.rst index 86138735879d..f7104c01b0f7 100644 --- a/Documentation/admin-guide/device-mapper/dm-flakey.rst +++ b/Documentation/admin-guide/device-mapper/dm-flakey.rst @@ -39,6 +39,10 @@ Optional feature parameters: If no feature parameters are present, during the periods of unreliability, all I/O returns errors. + error_reads: + All read I/O is failed with an error signalled. + Write I/O is handled correctly. + drop_writes: All write I/O is silently ignored. Read I/O is handled correctly. diff --git a/Documentation/admin-guide/ext4.rst b/Documentation/admin-guide/ext4.rst index 4c559e08d11e..5740d85439ff 100644 --- a/Documentation/admin-guide/ext4.rst +++ b/Documentation/admin-guide/ext4.rst @@ -489,9 +489,6 @@ Files in /sys/fs/ext4/<devname>: multiple of this tuning parameter if the stripe size is not set in the ext4 superblock - mb_max_inode_prealloc - The maximum length of per-inode ext4_prealloc_space list. - mb_max_to_scan The maximum number of extents the multiblock allocator will search to find the best extent. diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst index 86fd88492870..c18d94fa6470 100644 --- a/Documentation/admin-guide/kdump/vmcoreinfo.rst +++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst @@ -172,7 +172,7 @@ variables. Offset of the free_list's member. This value is used to compute the number of free pages. -Each zone has a free_area structure array called free_area[MAX_ORDER]. +Each zone has a free_area structure array called free_area[MAX_ORDER + 1]. The free_list represents a linked list of free page blocks. (list_head, next|prev) @@ -189,8 +189,8 @@ Offsets of the vmap_area's members. They carry vmalloc-specific information. Makedumpfile gets the start address of the vmalloc region from this. -(zone.free_area, MAX_ORDER) ---------------------------- +(zone.free_area, MAX_ORDER + 1) +------------------------------- Free areas descriptor. User-space tools use this value to iterate the free_area ranges. MAX_ORDER is used by the zone buddy allocator. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 10e2e5c3ff0b..9e5bab29685f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -339,6 +339,29 @@ This mode requires kvm-amd.avic=1. (Default when IOMMU HW support is present.) + amd_pstate= [X86] + disable + Do not enable amd_pstate as the default + scaling driver for the supported processors + passive + Use amd_pstate with passive mode as a scaling driver. + In this mode autonomous selection is disabled. + Driver requests a desired performance level and platform + tries to match the same performance level if it is + satisfied by guaranteed performance level. + active + Use amd_pstate_epp driver instance as the scaling driver, + driver provides a hint to the hardware if software wants + to bias toward performance (0x0) or energy efficiency (0xff) + to the CPPC firmware. then CPPC power algorithm will + calculate the runtime workload and adjust the realtime cores + frequency. + guided + Activate guided autonomous mode. Driver requests minimum and + maximum performance level and the platform autonomously + selects a performance level in this range and appropriate + to the current workload. + amijoy.map= [HW,JOY] Amiga joystick support Map of devices attached to JOY0DAT and JOY1DAT Format: <a>,<b> @@ -889,15 +912,14 @@ cs89x0_media= [HW,NET] Format: { rj45 | aui | bnc } - csdlock_debug= [KNL] Enable debug add-ons of cross-CPU function call - handling. When switched on, additional debug data is - printed to the console in case a hanging CPU is - detected, and that CPU is pinged again in order to try - to resolve the hang situation. - 0: disable csdlock debugging (default) - 1: enable basic csdlock debugging (minor impact) - ext: enable extended csdlock debugging (more impact, - but more data) + csdlock_debug= [KNL] Enable or disable debug add-ons of cross-CPU + function call handling. When switched on, + additional debug data is printed to the console + in case a hanging CPU is detected, and that + CPU is pinged again in order to try to resolve + the hang situation. The default value of this + option depends on the CSD_LOCK_WAIT_DEBUG_DEFAULT + Kconfig option. dasd= [HW,NET] See header of drivers/s390/block/dasd_devmap.c. @@ -1579,6 +1601,20 @@ dependencies. This only applies for fw_devlink=on|rpm. Format: <bool> + fw_devlink.sync_state = + [KNL] When all devices that could probe have finished + probing, this parameter controls what to do with + devices that haven't yet received their sync_state() + calls. + Format: { strict | timeout } + strict -- Default. Continue waiting on consumers to + probe successfully. + timeout -- Give up waiting on consumers and call + sync_state() on any devices that haven't yet + received their sync_state() calls after + deferred_probe_timeout has expired or by + late_initcall() if !CONFIG_MODULES. + gamecon.map[2|3]= [HW,JOY] Multisystem joystick and NES/SNES/PSX pad support via parallel port (up to 5 devices per port) @@ -3326,6 +3362,12 @@ specified, <module>.async_probe takes precedence for the specific module. + module.enable_dups_trace + [KNL] When CONFIG_MODULE_DEBUG_AUTOLOAD_DUPS is set, + this means that duplicate request_module() calls will + trigger a WARN_ON() instead of a pr_warn(). Note that + if MODULE_DEBUG_AUTOLOAD_DUPS_TRACE is set, WARN_ON()s + will always be issued and this option does nothing. module.sig_enforce [KNL] When CONFIG_MODULE_SIG is set, this means that modules without (valid) signatures will fail to load. @@ -3570,7 +3612,10 @@ emulation library even if a 387 maths coprocessor is present. - no5lvl [X86-64] Disable 5-level paging mode. Forces + no4lvl [RISCV] Disable 4-level and 5-level paging modes. Forces + kernel to use 3-level paging instead. + + no5lvl [X86-64,RISCV] Disable 5-level paging mode. Forces kernel to use 4-level paging instead. noaliencache [MM, NUMA, SLAB] Disables the allocation of alien @@ -3969,7 +4014,7 @@ [KNL] Minimal page reporting order Format: <integer> Adjust the minimal page reporting order. The page - reporting is disabled when it exceeds (MAX_ORDER-1). + reporting is disabled when it exceeds MAX_ORDER. panic= [KNL] Kernel behaviour on panic: delay <timeout> timeout > 0: seconds before rebooting @@ -6127,15 +6172,6 @@ later by a loaded module cannot be set this way. Example: sysctl.vm.swappiness=40 - sysfs.deprecated=0|1 [KNL] - Enable/disable old style sysfs layout for old udev - on older distributions. When this option is enabled - very new udev will not work anymore. When this option - is disabled (or CONFIG_SYSFS_DEPRECATED not compiled) - in older udev will not work anymore. - Default depends on CONFIG_SYSFS_DEPRECATED_V2 set in - the kernel configuration. - sysrq_always_enabled [KNL] Ignore sysrq setting - this boot parameter will @@ -7062,20 +7098,3 @@ xmon commands. off xmon is disabled. - amd_pstate= [X86] - disable - Do not enable amd_pstate as the default - scaling driver for the supported processors - passive - Use amd_pstate as a scaling driver, driver requests a - desired performance on this abstract scale and the power - management firmware translates the requests into actual - hardware states (core frequency, data fabric and memory - clocks etc.) - active - Use amd_pstate_epp driver instance as the scaling driver, - driver provides a hint to the hardware if software wants - to bias toward performance (0x0) or energy efficiency (0xff) - to the CPPC firmware. then CPPC power algorithm will - calculate the runtime workload and adjust the realtime cores - frequency. diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst index eed51a910c94..551083a396fb 100644 --- a/Documentation/admin-guide/mm/ksm.rst +++ b/Documentation/admin-guide/mm/ksm.rst @@ -157,6 +157,8 @@ stable_node_chains_prune_millisecs The effectiveness of KSM and MADV_MERGEABLE is shown in ``/sys/kernel/mm/ksm/``: +general_profit + how effective is KSM. The calculation is explained below. pages_shared how many shared pages are being used pages_sharing @@ -207,7 +209,8 @@ several times, which are unprofitable memory consumed. ksm_rmap_items * sizeof(rmap_item). where ksm_merging_pages is shown under the directory ``/proc/<pid>/``, - and ksm_rmap_items is shown in ``/proc/<pid>/ksm_stat``. + and ksm_rmap_items is shown in ``/proc/<pid>/ksm_stat``. The process profit + is also shown in ``/proc/<pid>/ksm_stat`` as ksm_process_profit. From the perspective of application, a high ratio of ``ksm_rmap_items`` to ``ksm_merging_pages`` means a bad madvise-applied policy, so developers or diff --git a/Documentation/admin-guide/mm/userfaultfd.rst b/Documentation/admin-guide/mm/userfaultfd.rst index 7dc823b56ca4..7c304e432205 100644 --- a/Documentation/admin-guide/mm/userfaultfd.rst +++ b/Documentation/admin-guide/mm/userfaultfd.rst @@ -219,6 +219,31 @@ former will have ``UFFD_PAGEFAULT_FLAG_WP`` set, the latter you still need to supply a page when ``UFFDIO_REGISTER_MODE_MISSING`` was used. +Userfaultfd write-protect mode currently behave differently on none ptes +(when e.g. page is missing) over different types of memories. + +For anonymous memory, ``ioctl(UFFDIO_WRITEPROTECT)`` will ignore none ptes +(e.g. when pages are missing and not populated). For file-backed memories +like shmem and hugetlbfs, none ptes will be write protected just like a +present pte. In other words, there will be a userfaultfd write fault +message generated when writing to a missing page on file typed memories, +as long as the page range was write-protected before. Such a message will +not be generated on anonymous memories by default. + +If the application wants to be able to write protect none ptes on anonymous +memory, one can pre-populate the memory with e.g. MADV_POPULATE_READ. On +newer kernels, one can also detect the feature UFFD_FEATURE_WP_UNPOPULATED +and set the feature bit in advance to make sure none ptes will also be +write protected even upon anonymous memory. + +When using ``UFFDIO_REGISTER_MODE_WP`` in combination with either +``UFFDIO_REGISTER_MODE_MISSING`` or ``UFFDIO_REGISTER_MODE_MINOR``, when +resolving missing / minor faults with ``UFFDIO_COPY`` or ``UFFDIO_CONTINUE`` +respectively, it may be desirable for the new page / mapping to be +write-protected (so future writes will also result in a WP fault). These ioctls +support a mode flag (``UFFDIO_COPY_MODE_WP`` or ``UFFDIO_CONTINUE_MODE_WP`` +respectively) to configure the mapping this way. + QEMU/KVM ======== diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index 6e5298b521b1..1cf40f69278c 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -303,13 +303,18 @@ efficiency frequency management method on AMD processors. AMD Pstate Driver Operation Modes ================================= -``amd_pstate`` CPPC has two operation modes: CPPC Autonomous(active) mode and -CPPC non-autonomous(passive) mode. -active mode and passive mode can be chosen by different kernel parameters. -When in Autonomous mode, CPPC ignores requests done in the Desired Performance -Target register and takes into account only the values set to the Minimum requested -performance, Maximum requested performance, and Energy Performance Preference -registers. When Autonomous is disabled, it only considers the Desired Performance Target. +``amd_pstate`` CPPC has 3 operation modes: autonomous (active) mode, +non-autonomous (passive) mode and guided autonomous (guided) mode. +Active/passive/guided mode can be chosen by different kernel parameters. + +- In autonomous mode, platform ignores the desired performance level request + and takes into account only the values set to the minimum, maximum and energy + performance preference registers. +- In non-autonomous mode, platform gets desired performance level + from OS directly through Desired Performance Register. +- In guided-autonomous mode, platform sets operating performance level + autonomously according to the current workload and within the limits set by + OS through min and max performance registers. Active Mode ------------ @@ -338,6 +343,15 @@ to the Performance Reduction Tolerance register. Above the nominal performance l processor must provide at least nominal performance requested and go higher if current operating conditions allow. +Guided Mode +----------- + +``amd_pstate=guided`` + +If ``amd_pstate=guided`` is passed to kernel command line option then this mode +is activated. In this mode, driver requests minimum and maximum performance +level and the platform autonomously selects a performance level in this range +and appropriate to the current workload. User Space Interface in ``sysfs`` - General =========================================== @@ -358,6 +372,9 @@ control its functionality at the system level. They are located in the "passive" The driver is functional and in the ``passive mode`` + "guided" + The driver is functional and in the ``guided mode`` + "disable" The driver is unregistered and not functional now. diff --git a/Documentation/admin-guide/serial-console.rst b/Documentation/admin-guide/serial-console.rst index 58b32832e50a..8c8b94e54e26 100644 --- a/Documentation/admin-guide/serial-console.rst +++ b/Documentation/admin-guide/serial-console.rst @@ -33,8 +33,11 @@ The format of this option is:: 9600n8. The maximum baudrate is 115200. You can specify multiple console= options on the kernel command line. -Output will appear on all of them. The last device will be used when -you open ``/dev/console``. So, for example:: + +The behavior is well defined when each device type is mentioned only once. +In this case, the output will appear on all requested consoles. And +the last device will be used when you open ``/dev/console``. +So, for example:: console=ttyS1,9600 console=tty0 @@ -42,7 +45,34 @@ defines that opening ``/dev/console`` will get you the current foreground virtual console, and kernel messages will appear on both the VGA console and the 2nd serial port (ttyS1 or COM2) at 9600 baud. -Note that you can only define one console per device type (serial, video). +The behavior is more complicated when the same device type is defined more +times. In this case, there are the following two rules: + +1. The output will appear only on the first device of each defined type. + +2. ``/dev/console`` will be associated with the first registered device. + Where the registration order depends on how kernel initializes various + subsystems. + + This rule is used also when the last console= parameter is not used + for other reasons. For example, because of a typo or because + the hardware is not available. + +The result might be surprising. For example, the following two command +lines have the same result: + + console=ttyS1,9600 console=tty0 console=tty1 + console=tty0 console=ttyS1,9600 console=tty1 + +The kernel messages are printed only on ``tty0`` and ``ttyS1``. And +``/dev/console`` gets associated with ``tty0``. It is because kernel +tries to register graphical consoles before serial ones. It does it +because of the default behavior when no console device is specified, +see below. + +Note that the last ``console=tty1`` parameter still makes a difference. +The kernel command line is used also by systemd. It would use the last +defined ``tty1`` as the login console. If no console device is specified, the first device found capable of acting as a system console will be used. At this time, the system diff --git a/Documentation/admin-guide/xfs.rst b/Documentation/admin-guide/xfs.rst index e2561416391c..3a9c041d7f6c 100644 --- a/Documentation/admin-guide/xfs.rst +++ b/Documentation/admin-guide/xfs.rst @@ -236,13 +236,14 @@ the dates listed above. Deprecated Mount Options ======================== -=========================== ================ +============================ ================ Name Removal Schedule -=========================== ================ +============================ ================ Mounting with V4 filesystem September 2030 +Mounting ascii-ci filesystem September 2030 ikeep/noikeep September 2025 attr2/noattr2 September 2025 -=========================== ================ +============================ ================ Removed Mount Options |