diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-platform_profile | 24 | ||||
| -rw-r--r-- | Documentation/Makefile | 2 | ||||
| -rw-r--r-- | Documentation/admin-guide/media/rkisp1.rst | 16 | ||||
| -rw-r--r-- | Documentation/admin-guide/syscall-user-dispatch.rst | 4 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/input/adc-keys.txt | 22 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/input/touchscreen/goodix.yaml | 1 | ||||
| -rw-r--r-- | Documentation/filesystems/overlayfs.rst | 8 | ||||
| -rw-r--r-- | Documentation/firmware-guide/acpi/gpio-properties.rst | 1 | ||||
| -rw-r--r-- | Documentation/kbuild/gcc-plugins.rst | 47 | ||||
| -rw-r--r-- | Documentation/kbuild/llvm.rst | 44 | ||||
| -rw-r--r-- | Documentation/kbuild/makefiles.rst | 2 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.rst | 2 | ||||
| -rw-r--r-- | Documentation/userspace-api/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/userspace-api/sysfs-platform_profile.rst | 42 | ||||
| -rw-r--r-- | Documentation/virt/kvm/nested-vmx.rst | 6 | ||||
| -rw-r--r-- | Documentation/virt/kvm/running-nested-guests.rst | 2 |
16 files changed, 188 insertions, 36 deletions
diff --git a/Documentation/ABI/testing/sysfs-platform_profile b/Documentation/ABI/testing/sysfs-platform_profile new file mode 100644 index 000000000000..9d6b89b66cca --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform_profile @@ -0,0 +1,24 @@ +What: /sys/firmware/acpi/platform_profile_choices +Date: October 2020 +Contact: Hans de Goede <hdegoede@redhat.com> +Description: This file contains a space-separated list of profiles supported for this device. + + Drivers must use the following standard profile-names: + + ============ ============================================ + low-power Low power consumption + cool Cooler operation + quiet Quieter operation + balanced Balance between low power consumption and performance + performance High performance operation + ============ ============================================ + + Userspace may expect drivers to offer more than one of these + standard profile names. + +What: /sys/firmware/acpi/platform_profile +Date: October 2020 +Contact: Hans de Goede <hdegoede@redhat.com> +Description: Reading this file gives the current selected profile for this + device. Writing this file with one of the strings from + platform_profile_choices changes the profile to the new value. diff --git a/Documentation/Makefile b/Documentation/Makefile index 61a7310b49e0..9c42dde97671 100644 --- a/Documentation/Makefile +++ b/Documentation/Makefile @@ -75,7 +75,7 @@ quiet_cmd_sphinx = SPHINX $@ --> file://$(abspath $(BUILDDIR)/$3/$4) cmd_sphinx = $(MAKE) BUILDDIR=$(abspath $(BUILDDIR)) $(build)=Documentation/userspace-api/media $2 && \ PYTHONDONTWRITEBYTECODE=1 \ BUILDDIR=$(abspath $(BUILDDIR)) SPHINX_CONF=$(abspath $(srctree)/$(src)/$5/$(SPHINX_CONF)) \ - $(PYTHON) $(srctree)/scripts/jobserver-exec \ + $(PYTHON3) $(srctree)/scripts/jobserver-exec \ $(SHELL) $(srctree)/Documentation/sphinx/parallel-wrapper.sh \ $(SPHINXBUILD) \ -b $2 \ diff --git a/Documentation/admin-guide/media/rkisp1.rst b/Documentation/admin-guide/media/rkisp1.rst index 2267e4fb475e..ccf418713623 100644 --- a/Documentation/admin-guide/media/rkisp1.rst +++ b/Documentation/admin-guide/media/rkisp1.rst @@ -13,6 +13,22 @@ This file documents the driver for the Rockchip ISP1 that is part of RK3288 and RK3399 SoCs. The driver is located under drivers/staging/media/rkisp1 and uses the Media-Controller API. +Revisions +========= + +There exist multiple smaller revisions to this ISP that got introduced in +later SoCs. Revisions can be found in the enum :c:type:`rkisp1_cif_isp_version` +in the UAPI and the revision of the ISP inside the running SoC can be read +in the field hw_revision of struct media_device_info as returned by +ioctl MEDIA_IOC_DEVICE_INFO. + +Versions in use are: + +- RKISP1_V10: used at least in rk3288 and rk3399 +- RKISP1_V11: declared in the original vendor code, but not used +- RKISP1_V12: used at least in rk3326 and px30 +- RKISP1_V13: used at least in rk1808 + Topology ======== .. _rkisp1_topology_graph: diff --git a/Documentation/admin-guide/syscall-user-dispatch.rst b/Documentation/admin-guide/syscall-user-dispatch.rst index a380d6515774..60314953c728 100644 --- a/Documentation/admin-guide/syscall-user-dispatch.rst +++ b/Documentation/admin-guide/syscall-user-dispatch.rst @@ -70,8 +70,8 @@ trampoline code on the vDSO, that trampoline is never intercepted. [selector] is a pointer to a char-sized region in the process memory region, that provides a quick way to enable disable syscall redirection thread-wide, without the need to invoke the kernel directly. selector -can be set to PR_SYS_DISPATCH_ON or PR_SYS_DISPATCH_OFF. Any other -value should terminate the program with a SIGSYS. +can be set to SYSCALL_DISPATCH_FILTER_ALLOW or SYSCALL_DISPATCH_FILTER_BLOCK. +Any other value should terminate the program with a SIGSYS. Security Notes -------------- diff --git a/Documentation/devicetree/bindings/input/adc-keys.txt b/Documentation/devicetree/bindings/input/adc-keys.txt index e551814629b4..6c8be6a9ace2 100644 --- a/Documentation/devicetree/bindings/input/adc-keys.txt +++ b/Documentation/devicetree/bindings/input/adc-keys.txt @@ -5,7 +5,8 @@ Required properties: - compatible: "adc-keys" - io-channels: Phandle to an ADC channel - io-channel-names = "buttons"; - - keyup-threshold-microvolt: Voltage at which all the keys are considered up. + - keyup-threshold-microvolt: Voltage above or equal to which all the keys are + considered up. Optional properties: - poll-interval: Poll interval time in milliseconds @@ -17,7 +18,12 @@ Each button (key) is represented as a sub-node of "adc-keys": Required subnode-properties: - label: Descriptive name of the key. - linux,code: Keycode to emit. - - press-threshold-microvolt: Voltage ADC input when this key is pressed. + - press-threshold-microvolt: voltage above or equal to which this key is + considered pressed. + +No two values of press-threshold-microvolt may be the same. +All values of press-threshold-microvolt must be less than +keyup-threshold-microvolt. Example: @@ -47,3 +53,15 @@ Example: press-threshold-microvolt = <500000>; }; }; + ++--------------------------------+------------------------+ +| 2.000.000 <= value | no key pressed | ++--------------------------------+------------------------+ +| 1.500.000 <= value < 2.000.000 | KEY_VOLUMEUP pressed | ++--------------------------------+------------------------+ +| 1.000.000 <= value < 1.500.000 | KEY_VOLUMEDOWN pressed | ++--------------------------------+------------------------+ +| 500.000 <= value < 1.000.000 | KEY_ENTER pressed | ++--------------------------------+------------------------+ +| value < 500.000 | no key pressed | ++--------------------------------+------------------------+ diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml index da5b0d87e16d..93f2ce3130ae 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml @@ -26,6 +26,7 @@ properties: - goodix,gt927 - goodix,gt9271 - goodix,gt928 + - goodix,gt9286 - goodix,gt967 reg: diff --git a/Documentation/filesystems/overlayfs.rst b/Documentation/filesystems/overlayfs.rst index 587a93973929..78240e29b0bb 100644 --- a/Documentation/filesystems/overlayfs.rst +++ b/Documentation/filesystems/overlayfs.rst @@ -586,6 +586,14 @@ without significant effort. The advantage of mounting with the "volatile" option is that all forms of sync calls to the upper filesystem are omitted. +In order to avoid a giving a false sense of safety, the syncfs (and fsync) +semantics of volatile mounts are slightly different than that of the rest of +VFS. If any writeback error occurs on the upperdir's filesystem after a +volatile mount takes place, all sync functions will return an error. Once this +condition is reached, the filesystem will not recover, and every subsequent sync +call will return an error, even if the upperdir has not experience a new error +since the last sync call. + When overlay is mounted with "volatile" option, the directory "$workdir/work/incompat/volatile" is created. During next mount, overlay checks for this directory and refuses to mount if present. This is a strong diff --git a/Documentation/firmware-guide/acpi/gpio-properties.rst b/Documentation/firmware-guide/acpi/gpio-properties.rst index b36aa3e743d8..4e264c16ddff 100644 --- a/Documentation/firmware-guide/acpi/gpio-properties.rst +++ b/Documentation/firmware-guide/acpi/gpio-properties.rst @@ -146,6 +146,7 @@ following rules (see also the examples): other words, it is not mandatory to fill all the GPIO lines - empty names are allowed (two quotation marks ``""`` correspond to an empty name) + - names inside one GPIO controller/expander must be unique Example of a GPIO controller of 16 lines, with an incomplete list with two empty names:: diff --git a/Documentation/kbuild/gcc-plugins.rst b/Documentation/kbuild/gcc-plugins.rst index 4b1c10f88e30..3349966f213d 100644 --- a/Documentation/kbuild/gcc-plugins.rst +++ b/Documentation/kbuild/gcc-plugins.rst @@ -11,16 +11,13 @@ compiler [1]_. They are useful for runtime instrumentation and static analysis. We can analyse, change and add further code during compilation via callbacks [2]_, GIMPLE [3]_, IPA [4]_ and RTL passes [5]_. -The GCC plugin infrastructure of the kernel supports all gcc versions from -4.5 to 6.0, building out-of-tree modules, cross-compilation and building in a -separate directory. -Plugin source files have to be compilable by both a C and a C++ compiler as well -because gcc versions 4.5 and 4.6 are compiled by a C compiler, -gcc-4.7 can be compiled by a C or a C++ compiler, -and versions 4.8+ can only be compiled by a C++ compiler. +The GCC plugin infrastructure of the kernel supports building out-of-tree +modules, cross-compilation and building in a separate directory. +Plugin source files have to be compilable by a C++ compiler. -Currently the GCC plugin infrastructure supports only the x86, arm, arm64 and -powerpc architectures. +Currently the GCC plugin infrastructure supports only some architectures. +Grep "select HAVE_GCC_PLUGINS" to find out which architectures support +GCC plugins. This infrastructure was ported from grsecurity [6]_ and PaX [7]_. @@ -47,20 +44,13 @@ Files This is a compatibility header for GCC plugins. It should be always included instead of individual gcc headers. -**$(src)/scripts/gcc-plugin.sh** - - This script checks the availability of the included headers in - gcc-common.h and chooses the proper host compiler to build the plugins - (gcc-4.7 can be built by either gcc or g++). - **$(src)/scripts/gcc-plugins/gcc-generate-gimple-pass.h, $(src)/scripts/gcc-plugins/gcc-generate-ipa-pass.h, $(src)/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h, $(src)/scripts/gcc-plugins/gcc-generate-rtl-pass.h** These headers automatically generate the registration structures for - GIMPLE, SIMPLE_IPA, IPA and RTL passes. They support all gcc versions - from 4.5 to 6.0. + GIMPLE, SIMPLE_IPA, IPA and RTL passes. They should be preferred to creating the structures by hand. @@ -68,21 +58,25 @@ Usage ===== You must install the gcc plugin headers for your gcc version, -e.g., on Ubuntu for gcc-4.9:: +e.g., on Ubuntu for gcc-10:: - apt-get install gcc-4.9-plugin-dev + apt-get install gcc-10-plugin-dev Or on Fedora:: dnf install gcc-plugin-devel -Enable a GCC plugin based feature in the kernel config:: +Enable the GCC plugin infrastructure and some plugin(s) you want to use +in the kernel config:: - CONFIG_GCC_PLUGIN_CYC_COMPLEXITY = y + CONFIG_GCC_PLUGINS=y + CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=y + CONFIG_GCC_PLUGIN_LATENT_ENTROPY=y + ... -To compile only the plugin(s):: +To compile the minimum tool set including the plugin(s):: - make gcc-plugins + make scripts or just run the kernel make and compile the whole kernel with the cyclomatic complexity GCC plugin. @@ -91,7 +85,8 @@ the cyclomatic complexity GCC plugin. 4. How to add a new GCC plugin ============================== -The GCC plugins are in $(src)/scripts/gcc-plugins/. You can use a file or a directory -here. It must be added to $(src)/scripts/gcc-plugins/Makefile, -$(src)/scripts/Makefile.gcc-plugins and $(src)/arch/Kconfig. +The GCC plugins are in scripts/gcc-plugins/. You need to put plugin source files +right under scripts/gcc-plugins/. Creating subdirectories is not supported. +It must be added to scripts/gcc-plugins/Makefile, scripts/Makefile.gcc-plugins +and a relevant Kconfig file. See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin. diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst index 21c847890d03..b18401d2ba82 100644 --- a/Documentation/kbuild/llvm.rst +++ b/Documentation/kbuild/llvm.rst @@ -63,6 +63,50 @@ They can be enabled individually. The full list of the parameters: :: Currently, the integrated assembler is disabled by default. You can pass ``LLVM_IAS=1`` to enable it. +Supported Architectures +----------------------- + +LLVM does not target all of the architectures that Linux supports and +just because a target is supported in LLVM does not mean that the kernel +will build or work without any issues. Below is a general summary of +architectures that currently work with ``CC=clang`` or ``LLVM=1``. Level +of support corresponds to "S" values in the MAINTAINERS files. If an +architecture is not present, it either means that LLVM does not target +it or there are known issues. Using the latest stable version of LLVM or +even the development tree will generally yield the best results. +An architecture's ``defconfig`` is generally expected to work well, +certain configurations may have problems that have not been uncovered +yet. Bug reports are always welcome at the issue tracker below! + +.. list-table:: + :widths: 10 10 10 + :header-rows: 1 + + * - Architecture + - Level of support + - ``make`` command + * - arm + - Supported + - ``LLVM=1`` + * - arm64 + - Supported + - ``LLVM=1`` + * - mips + - Maintained + - ``CC=clang`` + * - powerpc + - Maintained + - ``CC=clang`` + * - riscv + - Maintained + - ``CC=clang`` + * - s390 + - Maintained + - ``CC=clang`` + * - x86 + - Supported + - ``LLVM=1`` + Getting Help ------------ diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst index 9f6a11881951..300d8edcb994 100644 --- a/Documentation/kbuild/makefiles.rst +++ b/Documentation/kbuild/makefiles.rst @@ -755,7 +755,7 @@ more details, with real examples. bits on the scripts nonetheless. Kbuild provides variables $(CONFIG_SHELL), $(AWK), $(PERL), - $(PYTHON) and $(PYTHON3) to refer to interpreters for the respective + and $(PYTHON3) to refer to interpreters for the respective scripts. Example:: diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index c7b775da9554..fa544e9037b9 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -1196,7 +1196,7 @@ icmp_errors_use_inbound_ifaddr - BOOLEAN If non-zero, the message will be sent with the primary address of the interface that received the packet that caused the icmp error. - This is the behaviour network many administrators will expect from + This is the behaviour many network administrators will expect from a router. And it can make debugging complicated network layouts much easier. diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst index acd2cc2a538d..d29b020e5622 100644 --- a/Documentation/userspace-api/index.rst +++ b/Documentation/userspace-api/index.rst @@ -24,6 +24,7 @@ place where this information is gathered. ioctl/index iommu media/index + sysfs-platform_profile .. only:: subproject and html diff --git a/Documentation/userspace-api/sysfs-platform_profile.rst b/Documentation/userspace-api/sysfs-platform_profile.rst new file mode 100644 index 000000000000..c33a71263d9e --- /dev/null +++ b/Documentation/userspace-api/sysfs-platform_profile.rst @@ -0,0 +1,42 @@ +===================================================================== +Platform Profile Selection (e.g. /sys/firmware/acpi/platform_profile) +===================================================================== + +On modern systems the platform performance, temperature, fan and other +hardware related characteristics are often dynamically configurable. The +platform configuration is often automatically adjusted to the current +conditions by some automatic mechanism (which may very well live outside +the kernel). + +These auto platform adjustment mechanisms often can be configured with +one of several platform profiles, with either a bias towards low power +operation or towards performance. + +The purpose of the platform_profile attribute is to offer a generic sysfs +API for selecting the platform profile of these automatic mechanisms. + +Note that this API is only for selecting the platform profile, it is +NOT a goal of this API to allow monitoring the resulting performance +characteristics. Monitoring performance is best done with device/vendor +specific tools such as e.g. turbostat. + +Specifically when selecting a high performance profile the actual achieved +performance may be limited by various factors such as: the heat generated +by other components, room temperature, free air flow at the bottom of a +laptop, etc. It is explicitly NOT a goal of this API to let userspace know +about any sub-optimal conditions which are impeding reaching the requested +performance level. + +Since numbers on their own cannot represent the multiple variables that a +profile will adjust (power consumption, heat generation, etc) this API +uses strings to describe the various profiles. To make sure that userspace +gets a consistent experience the sysfs-platform_profile ABI document defines +a fixed set of profile names. Drivers *must* map their internal profile +representation onto this fixed set. + +If there is no good match when mapping then a new profile name may be +added. Drivers which wish to introduce new profile names must: + + 1. Explain why the existing profile names canot be used. + 2. Add the new profile name, along with a clear description of the + expected behaviour, to the sysfs-platform_profile ABI documentation. diff --git a/Documentation/virt/kvm/nested-vmx.rst b/Documentation/virt/kvm/nested-vmx.rst index 6ab4e35cee23..ac2095d41f02 100644 --- a/Documentation/virt/kvm/nested-vmx.rst +++ b/Documentation/virt/kvm/nested-vmx.rst @@ -37,8 +37,10 @@ call L2. Running nested VMX ------------------ -The nested VMX feature is disabled by default. It can be enabled by giving -the "nested=1" option to the kvm-intel module. +The nested VMX feature is enabled by default since Linux kernel v4.20. For +older Linux kernel, it can be enabled by giving the "nested=1" option to the +kvm-intel module. + No modifications are required to user space (qemu). However, qemu's default emulated CPU type (qemu64) does not list the "VMX" CPU feature, so it must be diff --git a/Documentation/virt/kvm/running-nested-guests.rst b/Documentation/virt/kvm/running-nested-guests.rst index d0a1fc754c84..bd70c69468ae 100644 --- a/Documentation/virt/kvm/running-nested-guests.rst +++ b/Documentation/virt/kvm/running-nested-guests.rst @@ -74,7 +74,7 @@ few: Enabling "nested" (x86) ----------------------- -From Linux kernel v4.19 onwards, the ``nested`` KVM parameter is enabled +From Linux kernel v4.20 onwards, the ``nested`` KVM parameter is enabled by default for Intel and AMD. (Though your Linux distribution might override this default.) |