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-rw-r--r--Documentation/admin-guide/README.rst2
-rw-r--r--Documentation/admin-guide/cgroup-v2.rst7
-rw-r--r--Documentation/admin-guide/device-mapper/index.rst1
-rw-r--r--Documentation/admin-guide/ext4.rst7
-rw-r--r--Documentation/admin-guide/kdump/vmcoreinfo.rst16
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt75
-rw-r--r--Documentation/admin-guide/laptops/thinkpad-acpi.rst32
-rw-r--r--Documentation/admin-guide/mm/transhuge.rst3
-rw-r--r--Documentation/admin-guide/pm/cpufreq.rst6
-rw-r--r--Documentation/admin-guide/pm/intel_pstate.rst17
-rw-r--r--Documentation/admin-guide/sysctl/kernel.rst54
11 files changed, 209 insertions, 11 deletions
diff --git a/Documentation/admin-guide/README.rst b/Documentation/admin-guide/README.rst
index 5fb526900023..5aad534233cd 100644
--- a/Documentation/admin-guide/README.rst
+++ b/Documentation/admin-guide/README.rst
@@ -258,7 +258,7 @@ Configuring the kernel
Compiling the kernel
--------------------
- - Make sure you have at least gcc 4.6 available.
+ - Make sure you have at least gcc 4.9 available.
For more information, refer to :ref:`Documentation/process/changes.rst <changes>`.
Please note that you can still run a.out user programs with this kernel.
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index e454957683c9..fa4018afa5a4 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1356,8 +1356,8 @@ PAGE_SIZE multiple when read back.
thp_fault_alloc
Number of transparent hugepages which were allocated to satisfy
- a page fault, including COW faults. This counter is not present
- when CONFIG_TRANSPARENT_HUGEPAGE is not set.
+ a page fault. This counter is not present when CONFIG_TRANSPARENT_HUGEPAGE
+ is not set.
thp_collapse_alloc
Number of transparent hugepages which were allocated to allow
@@ -1483,8 +1483,7 @@ IO Interface Files
~~~~~~~~~~~~~~~~~~
io.stat
- A read-only nested-keyed file which exists on non-root
- cgroups.
+ A read-only nested-keyed file.
Lines are keyed by $MAJ:$MIN device numbers and not ordered.
The following nested keys are defined.
diff --git a/Documentation/admin-guide/device-mapper/index.rst b/Documentation/admin-guide/device-mapper/index.rst
index ec62fcc8eece..6cf8adc86fa8 100644
--- a/Documentation/admin-guide/device-mapper/index.rst
+++ b/Documentation/admin-guide/device-mapper/index.rst
@@ -11,6 +11,7 @@ Device Mapper
dm-clone
dm-crypt
dm-dust
+ dm-ebs
dm-flakey
dm-init
dm-integrity
diff --git a/Documentation/admin-guide/ext4.rst b/Documentation/admin-guide/ext4.rst
index bc3abfb33476..a683976fad6d 100644
--- a/Documentation/admin-guide/ext4.rst
+++ b/Documentation/admin-guide/ext4.rst
@@ -395,6 +395,13 @@ When mounting an ext4 filesystem, the following option are accepted:
Documentation/filesystems/dax.txt. Note that this option is
incompatible with data=journal.
+ inlinecrypt
+ When possible, encrypt/decrypt the contents of encrypted files using the
+ blk-crypto framework rather than filesystem-layer encryption. This
+ allows the use of inline encryption hardware. The on-disk format is
+ unaffected. For more details, see
+ Documentation/block/inline-encryption.rst.
+
Data Mode
=========
There are 3 different data modes:
diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst
index e4ee8b2db604..2baad0bfb09d 100644
--- a/Documentation/admin-guide/kdump/vmcoreinfo.rst
+++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst
@@ -93,6 +93,11 @@ It exists in the sparse memory mapping model, and it is also somewhat
similar to the mem_map variable, both of them are used to translate an
address.
+MAX_PHYSMEM_BITS
+----------------
+
+Defines the maximum supported physical address space memory.
+
page
----
@@ -399,6 +404,17 @@ KERNELPACMASK
The mask to extract the Pointer Authentication Code from a kernel virtual
address.
+TCR_EL1.T1SZ
+------------
+
+Indicates the size offset of the memory region addressed by TTBR1_EL1.
+The region size is 2^(64-T1SZ) bytes.
+
+TTBR1_EL1 is the table base address register specified by ARMv8-A
+architecture which is used to lookup the page-tables for the Virtual
+addresses in the higher VA range (refer to ARMv8 ARM document for
+more details).
+
arm
===
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index d325726ff425..ff5018b39ed0 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -703,6 +703,11 @@
cpufreq.off=1 [CPU_FREQ]
disable the cpufreq sub-system
+ cpufreq.default_governor=
+ [CPU_FREQ] Name of the default cpufreq governor or
+ policy to use. This governor must be registered in the
+ kernel before the cpufreq driver probes.
+
cpu_init_udelay=N
[X86] Delay for N microsec between assert and de-assert
of APIC INIT to start processors. This delay occurs
@@ -3081,6 +3086,8 @@
no5lvl [X86-64] Disable 5-level paging mode. Forces
kernel to use 4-level paging instead.
+ nofsgsbase [X86] Disables FSGSBASE instructions.
+
no_console_suspend
[HW] Never suspend the console
Disable suspending of consoles during suspend and
@@ -4040,6 +4047,14 @@
latencies, which will choose a value aligned
with the appropriate hardware boundaries.
+ rcutree.rcu_min_cached_objs= [KNL]
+ Minimum number of objects which are cached and
+ maintained per one CPU. Object size is equal
+ to PAGE_SIZE. The cache allows to reduce the
+ pressure to page allocator, also it makes the
+ whole algorithm to behave better in low memory
+ condition.
+
rcutree.jiffies_till_first_fqs= [KNL]
Set delay from grace-period initialization to
first attempt to force quiescent states.
@@ -4260,6 +4275,20 @@
Set time (jiffies) between CPU-hotplug operations,
or zero to disable CPU-hotplug testing.
+ rcutorture.read_exit= [KNL]
+ Set the number of read-then-exit kthreads used
+ to test the interaction of RCU updaters and
+ task-exit processing.
+
+ rcutorture.read_exit_burst= [KNL]
+ The number of times in a given read-then-exit
+ episode that a set of read-then-exit kthreads
+ is spawned.
+
+ rcutorture.read_exit_delay= [KNL]
+ The delay, in seconds, between successive
+ read-then-exit testing episodes.
+
rcutorture.shuffle_interval= [KNL]
Set task-shuffle interval (s). Shuffling tasks
allows some CPUs to go into dyntick-idle mode
@@ -4409,6 +4438,45 @@
reboot_cpu is s[mp]#### with #### being the processor
to be used for rebooting.
+ refscale.holdoff= [KNL]
+ Set test-start holdoff period. The purpose of
+ this parameter is to delay the start of the
+ test until boot completes in order to avoid
+ interference.
+
+ refscale.loops= [KNL]
+ Set the number of loops over the synchronization
+ primitive under test. Increasing this number
+ reduces noise due to loop start/end overhead,
+ but the default has already reduced the per-pass
+ noise to a handful of picoseconds on ca. 2020
+ x86 laptops.
+
+ refscale.nreaders= [KNL]
+ Set number of readers. The default value of -1
+ selects N, where N is roughly 75% of the number
+ of CPUs. A value of zero is an interesting choice.
+
+ refscale.nruns= [KNL]
+ Set number of runs, each of which is dumped onto
+ the console log.
+
+ refscale.readdelay= [KNL]
+ Set the read-side critical-section duration,
+ measured in microseconds.
+
+ refscale.scale_type= [KNL]
+ Specify the read-protection implementation to test.
+
+ refscale.shutdown= [KNL]
+ Shut down the system at the end of the performance
+ test. This defaults to 1 (shut it down) when
+ rcuperf is built into the kernel and to 0 (leave
+ it running) when rcuperf is built as a module.
+
+ refscale.verbose= [KNL]
+ Enable additional printk() statements.
+
relax_domain_level=
[KNL, SMP] Set scheduler's default relax_domain_level.
See Documentation/admin-guide/cgroup-v1/cpusets.rst.
@@ -5084,6 +5152,13 @@
Prevent the CPU-hotplug component of torturing
until after init has spawned.
+ torture.ftrace_dump_at_shutdown= [KNL]
+ Dump the ftrace buffer at torture-test shutdown,
+ even if there were no errors. This can be a
+ very costly operation when many torture tests
+ are running concurrently, especially on systems
+ with rotating-rust storage.
+
tp720= [HW,PS2]
tpm_suspend_pcr=[HW,TPM]
diff --git a/Documentation/admin-guide/laptops/thinkpad-acpi.rst b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
index 69b7ce905cba..5e477869df18 100644
--- a/Documentation/admin-guide/laptops/thinkpad-acpi.rst
+++ b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
@@ -50,6 +50,7 @@ detailed description):
- WAN enable and disable
- UWB enable and disable
- LCD Shadow (PrivacyGuard) enable and disable
+ - Lap mode sensor
A compatibility table by model and feature is maintained on the web
site, http://ibm-acpi.sf.net/. I appreciate any success or failure
@@ -1432,6 +1433,20 @@ The first command ensures the best viewing angle and the latter one turns
on the feature, restricting the viewing angles.
+DYTC Lapmode sensor
+------------------
+
+sysfs: dytc_lapmode
+
+Newer thinkpads and mobile workstations have the ability to determine if
+the device is in deskmode or lapmode. This feature is used by user space
+to decide if WWAN transmission can be increased to maximum power and is
+also useful for understanding the different thermal modes available as
+they differ between desk and lap mode.
+
+The property is read-only. If the platform doesn't have support the sysfs
+class is not created.
+
EXPERIMENTAL: UWB
-----------------
@@ -1470,6 +1485,23 @@ For more details about which buttons will appear depending on the mode, please
review the laptop's user guide:
http://www.lenovo.com/shop/americas/content/user_guides/x1carbon_2_ug_en.pdf
+Battery charge control
+----------------------
+
+sysfs attributes:
+/sys/class/power_supply/BAT*/charge_control_{start,end}_threshold
+
+These two attributes are created for those batteries that are supported by the
+driver. They enable the user to control the battery charge thresholds of the
+given battery. Both values may be read and set. `charge_control_start_threshold`
+accepts an integer between 0 and 99 (inclusive); this value represents a battery
+percentage level, below which charging will begin. `charge_control_end_threshold`
+accepts an integer between 1 and 100 (inclusive); this value represents a battery
+percentage level, above which charging will stop.
+
+The exact semantics of the attributes may be found in
+Documentation/ABI/testing/sysfs-class-power.
+
Multiple Commands, Module Parameters
------------------------------------
diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst
index 6a233e42be08..b2acd0d395ca 100644
--- a/Documentation/admin-guide/mm/transhuge.rst
+++ b/Documentation/admin-guide/mm/transhuge.rst
@@ -305,8 +305,7 @@ monitor how successfully the system is providing huge pages for use.
thp_fault_alloc
is incremented every time a huge page is successfully
- allocated to handle a page fault. This applies to both the
- first time a page is faulted and for COW faults.
+ allocated to handle a page fault.
thp_collapse_alloc
is incremented by khugepaged when it has found
diff --git a/Documentation/admin-guide/pm/cpufreq.rst b/Documentation/admin-guide/pm/cpufreq.rst
index 0c74a7784964..368e612145d2 100644
--- a/Documentation/admin-guide/pm/cpufreq.rst
+++ b/Documentation/admin-guide/pm/cpufreq.rst
@@ -147,9 +147,9 @@ CPUs in it.
The next major initialization step for a new policy object is to attach a
scaling governor to it (to begin with, that is the default scaling governor
-determined by the kernel configuration, but it may be changed later
-via ``sysfs``). First, a pointer to the new policy object is passed to the
-governor's ``->init()`` callback which is expected to initialize all of the
+determined by the kernel command line or configuration, but it may be changed
+later via ``sysfs``). First, a pointer to the new policy object is passed to
+the governor's ``->init()`` callback which is expected to initialize all of the
data structures necessary to handle the given policy and, possibly, to add
a governor ``sysfs`` interface to it. Next, the governor is started by
invoking its ``->start()`` callback.
diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst
index f8487b1276f0..9db924904d2c 100644
--- a/Documentation/admin-guide/pm/intel_pstate.rst
+++ b/Documentation/admin-guide/pm/intel_pstate.rst
@@ -431,6 +431,17 @@ argument is passed to the kernel in the command line.
supported in the current configuration, writes to this attribute will
fail with an appropriate error.
+``energy_efficiency``
+ This attribute is only present on platforms, which have CPUs matching
+ Kaby Lake or Coffee Lake desktop CPU model. By default
+ energy efficiency optimizations are disabled on these CPU models in HWP
+ mode by this driver. Enabling energy efficiency may limit maximum
+ operating frequency in both HWP and non HWP mode. In non HWP mode,
+ optimizations are done only in the turbo frequency range. In HWP mode,
+ optimizations are done in the entire frequency range. Setting this
+ attribute to "1" enables energy efficiency optimizations and setting
+ to "0" disables energy efficiency optimizations.
+
Interpretation of Policy Attributes
-----------------------------------
@@ -554,7 +565,11 @@ somewhere between the two extremes:
Strings written to the ``energy_performance_preference`` attribute are
internally translated to integer values written to the processor's
Energy-Performance Preference (EPP) knob (if supported) or its
-Energy-Performance Bias (EPB) knob.
+Energy-Performance Bias (EPB) knob. It is also possible to write a positive
+integer value between 0 to 255, if the EPP feature is present. If the EPP
+feature is not present, writing integer value to this attribute is not
+supported. In this case, user can use
+ "/sys/devices/system/cpu/cpu*/power/energy_perf_bias" interface.
[Note that tasks may by migrated from one CPU to another by the scheduler's
load-balancing algorithm and if different energy vs performance hints are
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index 292e3d0188f6..2ae9669eb22c 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -1094,6 +1094,60 @@ Enables/disables scheduler statistics. Enabling this feature
incurs a small amount of overhead in the scheduler but is
useful for debugging and performance tuning.
+sched_util_clamp_min:
+=====================
+
+Max allowed *minimum* utilization.
+
+Default value is 1024, which is the maximum possible value.
+
+It means that any requested uclamp.min value cannot be greater than
+sched_util_clamp_min, i.e., it is restricted to the range
+[0:sched_util_clamp_min].
+
+sched_util_clamp_max:
+=====================
+
+Max allowed *maximum* utilization.
+
+Default value is 1024, which is the maximum possible value.
+
+It means that any requested uclamp.max value cannot be greater than
+sched_util_clamp_max, i.e., it is restricted to the range
+[0:sched_util_clamp_max].
+
+sched_util_clamp_min_rt_default:
+================================
+
+By default Linux is tuned for performance. Which means that RT tasks always run
+at the highest frequency and most capable (highest capacity) CPU (in
+heterogeneous systems).
+
+Uclamp achieves this by setting the requested uclamp.min of all RT tasks to
+1024 by default, which effectively boosts the tasks to run at the highest
+frequency and biases them to run on the biggest CPU.
+
+This knob allows admins to change the default behavior when uclamp is being
+used. In battery powered devices particularly, running at the maximum
+capacity and frequency will increase energy consumption and shorten the battery
+life.
+
+This knob is only effective for RT tasks which the user hasn't modified their
+requested uclamp.min value via sched_setattr() syscall.
+
+This knob will not escape the range constraint imposed by sched_util_clamp_min
+defined above.
+
+For example if
+
+ sched_util_clamp_min_rt_default = 800
+ sched_util_clamp_min = 600
+
+Then the boost will be clamped to 600 because 800 is outside of the permissible
+range of [0:600]. This could happen for instance if a powersave mode will
+restrict all boosts temporarily by modifying sched_util_clamp_min. As soon as
+this restriction is lifted, the requested sched_util_clamp_min_rt_default
+will take effect.
seccomp
=======