diff options
Diffstat (limited to 'Documentation')
23 files changed, 311 insertions, 90 deletions
diff --git a/Documentation/ABI/testing/sysfs-platform-dell-laptop b/Documentation/ABI/testing/sysfs-platform-dell-laptop index 8c6a0b8e1131..9b917c7453de 100644 --- a/Documentation/ABI/testing/sysfs-platform-dell-laptop +++ b/Documentation/ABI/testing/sysfs-platform-dell-laptop @@ -2,7 +2,7 @@ What: /sys/class/leds/dell::kbd_backlight/als_enabled Date: December 2014 KernelVersion: 3.19 Contact: Gabriele Mazzotta <gabriele.mzt@gmail.com>, - Pali Rohár <pali.rohar@gmail.com> + Pali Rohár <pali@kernel.org> Description: This file allows to control the automatic keyboard illumination mode on some systems that have an ambient @@ -13,7 +13,7 @@ What: /sys/class/leds/dell::kbd_backlight/als_setting Date: December 2014 KernelVersion: 3.19 Contact: Gabriele Mazzotta <gabriele.mzt@gmail.com>, - Pali Rohár <pali.rohar@gmail.com> + Pali Rohár <pali@kernel.org> Description: This file allows to specifiy the on/off threshold value, as reported by the ambient light sensor. @@ -22,7 +22,7 @@ What: /sys/class/leds/dell::kbd_backlight/start_triggers Date: December 2014 KernelVersion: 3.19 Contact: Gabriele Mazzotta <gabriele.mzt@gmail.com>, - Pali Rohár <pali.rohar@gmail.com> + Pali Rohár <pali@kernel.org> Description: This file allows to control the input triggers that turn on the keyboard backlight illumination that is @@ -45,7 +45,7 @@ What: /sys/class/leds/dell::kbd_backlight/stop_timeout Date: December 2014 KernelVersion: 3.19 Contact: Gabriele Mazzotta <gabriele.mzt@gmail.com>, - Pali Rohár <pali.rohar@gmail.com> + Pali Rohár <pali@kernel.org> Description: This file allows to specify the interval after which the keyboard illumination is disabled because of inactivity. diff --git a/Documentation/admin-guide/binderfs.rst b/Documentation/admin-guide/binderfs.rst index c009671f8434..8243af9b3510 100644 --- a/Documentation/admin-guide/binderfs.rst +++ b/Documentation/admin-guide/binderfs.rst @@ -33,6 +33,12 @@ max a per-instance limit. If ``max=<count>`` is set then only ``<count>`` number of binder devices can be allocated in this binderfs instance. +stats + Using ``stats=global`` enables global binder statistics. + ``stats=global`` is only available for a binderfs instance mounted in the + initial user namespace. An attempt to use the option to mount a binderfs + instance in another user namespace will return a permission error. + Allocating binder Devices ------------------------- diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 86aae1fa099a..f2a93c8679e8 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -685,7 +685,7 @@ coredump_filter= [KNL] Change the default value for /proc/<pid>/coredump_filter. - See also Documentation/filesystems/proc.txt. + See also Documentation/filesystems/proc.rst. coresight_cpu_debug.enable [ARM,ARM64] @@ -962,7 +962,7 @@ edid/1680x1050.bin, or edid/1920x1080.bin is given and no file with the same name exists. Details and instructions how to build your own EDID data are - available in Documentation/driver-api/edid.rst. An EDID + available in Documentation/admin-guide/edid.rst. An EDID data set will only be used for a particular connector, if its name and a colon are prepended to the EDID name. Each connector may use a unique EDID data @@ -992,10 +992,6 @@ Documentation/admin-guide/dynamic-debug-howto.rst for details. - nompx [X86] Disables Intel Memory Protection Extensions. - See Documentation/x86/intel_mpx.rst for more - information about the feature. - nopku [X86] Disable Memory Protection Keys CPU feature found in some Intel CPUs. @@ -1475,6 +1471,14 @@ hpet_mmap= [X86, HPET_MMAP] Allow userspace to mmap HPET registers. Default set by CONFIG_HPET_MMAP_DEFAULT. + hugetlb_cma= [HW] The size of a cma area used for allocation + of gigantic hugepages. + Format: nn[KMGTPE] + + Reserve a cma area of given size and allocate gigantic + hugepages using the cma allocator. If enabled, the + boot-time allocation of gigantic hugepages is skipped. + hugepages= [HW,X86-32,IA-64] HugeTLB pages to allocate at boot. hugepagesz= [HW,IA-64,PPC,X86-64] The size of the HugeTLB pages. On x86-64 and powerpc, this option can be specified diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index 335696d3360d..39c95c0e13d3 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -446,6 +446,27 @@ Notes: successful IPC object allocation. If an IPC object allocation syscall fails, it is undefined if the value remains unmodified or is reset to -1. +modprobe: +========= + +The path to the usermode helper for autoloading kernel modules, by +default "/sbin/modprobe". This binary is executed when the kernel +requests a module. For example, if userspace passes an unknown +filesystem type to mount(), then the kernel will automatically request +the corresponding filesystem module by executing this usermode helper. +This usermode helper should insert the needed module into the kernel. + +This sysctl only affects module autoloading. It has no effect on the +ability to explicitly insert modules. + +If this sysctl is set to the empty string, then module autoloading is +completely disabled. The kernel will not try to execute a usermode +helper at all, nor will it call the kernel_module_request LSM hook. + +If CONFIG_STATIC_USERMODEHELPER=y is set in the kernel configuration, +then the configured static usermode helper overrides this sysctl, +except that the empty string is still accepted to completely disable +module autoloading as described above. nmi_watchdog ============ diff --git a/Documentation/admin-guide/sysrq.rst b/Documentation/admin-guide/sysrq.rst index 72b2cfb066f4..a46209f4636c 100644 --- a/Documentation/admin-guide/sysrq.rst +++ b/Documentation/admin-guide/sysrq.rst @@ -48,9 +48,10 @@ always allowed (by a user with admin privileges). How do I use the magic SysRq key? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -On x86 - You press the key combo :kbd:`ALT-SysRq-<command key>`. +On x86 + You press the key combo :kbd:`ALT-SysRq-<command key>`. -.. note:: + .. note:: Some keyboards may not have a key labeled 'SysRq'. The 'SysRq' key is also known as the 'Print Screen' key. Also some keyboards cannot @@ -58,14 +59,15 @@ On x86 - You press the key combo :kbd:`ALT-SysRq-<command key>`. have better luck with press :kbd:`Alt`, press :kbd:`SysRq`, release :kbd:`SysRq`, press :kbd:`<command key>`, release everything. -On SPARC - You press :kbd:`ALT-STOP-<command key>`, I believe. +On SPARC + You press :kbd:`ALT-STOP-<command key>`, I believe. On the serial console (PC style standard serial ports only) You send a ``BREAK``, then within 5 seconds a command key. Sending ``BREAK`` twice is interpreted as a normal BREAK. On PowerPC - Press :kbd:`ALT - Print Screen` (or :kbd:`F13`) - :kbd:`<command key>`, + Press :kbd:`ALT - Print Screen` (or :kbd:`F13`) - :kbd:`<command key>`. :kbd:`Print Screen` (or :kbd:`F13`) - :kbd:`<command key>` may suffice. On other @@ -73,7 +75,7 @@ On other let me know so I can add them to this section. On all - write a character to /proc/sysrq-trigger. e.g.:: + Write a character to /proc/sysrq-trigger. e.g.:: echo t > /proc/sysrq-trigger @@ -282,7 +284,7 @@ Just ask them on the linux-kernel mailing list: Credits ~~~~~~~ -Written by Mydraal <vulpyne@vulpyne.net> -Updated by Adam Sulmicki <adam@cfar.umd.edu> -Updated by Jeremy M. Dolan <jmd@turbogeek.org> 2001/01/28 10:15:59 -Added to by Crutcher Dunnavant <crutcher+kernel@datastacks.com> +- Written by Mydraal <vulpyne@vulpyne.net> +- Updated by Adam Sulmicki <adam@cfar.umd.edu> +- Updated by Jeremy M. Dolan <jmd@turbogeek.org> 2001/01/28 10:15:59 +- Added to by Crutcher Dunnavant <crutcher+kernel@datastacks.com> diff --git a/Documentation/devicetree/bindings/fpga/fpga-region.txt b/Documentation/devicetree/bindings/fpga/fpga-region.txt index 90c44694a30b..8ab19d1d3f9a 100644 --- a/Documentation/devicetree/bindings/fpga/fpga-region.txt +++ b/Documentation/devicetree/bindings/fpga/fpga-region.txt @@ -263,7 +263,7 @@ Overlay contains: gpio@10040 { compatible = "altr,pio-1.0"; reg = <0x10040 0x20>; - altr,gpio-bank-width = <4>; + altr,ngpio = <4>; #gpio-cells = <2>; clocks = <2>; gpio-controller; @@ -468,8 +468,7 @@ programming is the FPGA based bridge of fpga_region1. compatible = "altr,pio-1.0"; reg = <0x10040 0x20>; clocks = <0x2>; - altr,gpio-bank-width = <0x4>; - resetvalue = <0x0>; + altr,ngpio = <0x4>; #gpio-cells = <0x2>; gpio-controller; }; diff --git a/Documentation/devicetree/bindings/ipmi/aspeed-kcs-bmc.txt b/Documentation/devicetree/bindings/ipmi/aspeed-kcs-bmc.txt index d98a9bf45d6c..193e71ca96b0 100644 --- a/Documentation/devicetree/bindings/ipmi/aspeed-kcs-bmc.txt +++ b/Documentation/devicetree/bindings/ipmi/aspeed-kcs-bmc.txt @@ -1,9 +1,10 @@ -* Aspeed KCS (Keyboard Controller Style) IPMI interface +# Aspeed KCS (Keyboard Controller Style) IPMI interface The Aspeed SOCs (AST2400 and AST2500) are commonly used as BMCs (Baseboard Management Controllers) and the KCS interface can be used to perform in-band IPMI communication with their host. +## v1 Required properties: - compatible : should be one of "aspeed,ast2400-kcs-bmc" @@ -12,14 +13,21 @@ Required properties: - kcs_chan : The LPC channel number in the controller - kcs_addr : The host CPU IO map address +## v2 +Required properties: +- compatible : should be one of + "aspeed,ast2400-kcs-bmc-v2" + "aspeed,ast2500-kcs-bmc-v2" +- reg : The address and size of the IDR, ODR and STR registers +- interrupts : interrupt generated by the controller +- aspeed,lpc-io-reg : The host CPU LPC IO address for the device Example: - kcs3: kcs3@0 { - compatible = "aspeed,ast2500-kcs-bmc"; - reg = <0x0 0x80>; + kcs3: kcs@24 { + compatible = "aspeed,ast2500-kcs-bmc-v2"; + reg = <0x24 0x1>, <0x30 0x1>, <0x3c 0x1>; + aspeed,lpc-reg = <0xca2>; interrupts = <8>; - kcs_chan = <3>; - kcs_addr = <0xCA2>; status = "okay"; }; diff --git a/Documentation/devicetree/bindings/pwm/google,cros-ec-pwm.txt b/Documentation/devicetree/bindings/pwm/google,cros-ec-pwm.txt deleted file mode 100644 index 472bd46ab5a4..000000000000 --- a/Documentation/devicetree/bindings/pwm/google,cros-ec-pwm.txt +++ /dev/null @@ -1,23 +0,0 @@ -* PWM controlled by ChromeOS EC - -Google's ChromeOS EC PWM is a simple PWM attached to the Embedded Controller -(EC) and controlled via a host-command interface. - -An EC PWM node should be only found as a sub-node of the EC node (see -Documentation/devicetree/bindings/mfd/cros-ec.txt). - -Required properties: -- compatible: Must contain "google,cros-ec-pwm" -- #pwm-cells: Should be 1. The cell specifies the PWM index. - -Example: - cros-ec@0 { - compatible = "google,cros-ec-spi"; - - ... - - cros_ec_pwm: ec-pwm { - compatible = "google,cros-ec-pwm"; - #pwm-cells = <1>; - }; - }; diff --git a/Documentation/devicetree/bindings/pwm/google,cros-ec-pwm.yaml b/Documentation/devicetree/bindings/pwm/google,cros-ec-pwm.yaml new file mode 100644 index 000000000000..24c217b76580 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/google,cros-ec-pwm.yaml @@ -0,0 +1,40 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pwm/google,cros-ec-pwm.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: PWM controlled by ChromeOS EC + +maintainers: + - Thierry Reding <thierry.reding@gmail.com> + - '"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>' + +description: | + Google's ChromeOS EC PWM is a simple PWM attached to the Embedded Controller + (EC) and controlled via a host-command interface. + An EC PWM node should be only found as a sub-node of the EC node (see + Documentation/devicetree/bindings/mfd/cros-ec.txt). + +properties: + compatible: + const: google,cros-ec-pwm + "#pwm-cells": + description: The cell specifies the PWM index. + const: 1 + +required: + - compatible + - '#pwm-cells' + +additionalProperties: false + +examples: + - | + cros-ec@0 { + compatible = "google,cros-ec-spi"; + cros_ec_pwm: ec-pwm { + compatible = "google,cros-ec-pwm"; + #pwm-cells = <1>; + }; + }; diff --git a/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt b/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt index 0a69eadf44ce..74c41e34c3b6 100644 --- a/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt +++ b/Documentation/devicetree/bindings/pwm/nvidia,tegra20-pwm.txt @@ -9,6 +9,7 @@ Required properties: - "nvidia,tegra132-pwm", "nvidia,tegra20-pwm": for Tegra132 - "nvidia,tegra210-pwm", "nvidia,tegra20-pwm": for Tegra210 - "nvidia,tegra186-pwm": for Tegra186 + - "nvidia,tegra194-pwm": for Tegra194 - reg: physical base address and length of the controller's registers - #pwm-cells: should be 2. See pwm.yaml in this directory for a description of the cells format. diff --git a/Documentation/devicetree/bindings/sound/cirrus,cs42l51.yaml b/Documentation/devicetree/bindings/sound/cirrus,cs42l51.yaml index efce847a3408..83f44f07ac3f 100644 --- a/Documentation/devicetree/bindings/sound/cirrus,cs42l51.yaml +++ b/Documentation/devicetree/bindings/sound/cirrus,cs42l51.yaml @@ -49,7 +49,7 @@ required: examples: - | #include <dt-bindings/gpio/gpio.h> - i2c@0 { + i2c { #address-cells = <1>; #size-cells = <0>; diff --git a/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml new file mode 100644 index 000000000000..e83026fef2e9 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml @@ -0,0 +1,65 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/watchdog/ti,rti-wdt.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Texas Instruments K3 SoC Watchdog Timer + +maintainers: + - Tero Kristo <t-kristo@ti.com> + +description: + The TI K3 SoC watchdog timer is implemented via the RTI (Real Time + Interrupt) IP module. This timer adds a support for windowed watchdog + mode, which will signal an error if it is pinged outside the watchdog + time window, meaning either too early or too late. The error signal + generated can be routed to either interrupt a safety controller or + to directly reset the SoC. + +allOf: + - $ref: "watchdog.yaml#" + +properties: + compatible: + enum: + - ti,j7-rti-wdt + + reg: + maxItems: 1 + + clocks: + maxItems: 1 + + power-domains: + maxItems: 1 + + assigned-clocks: + maxItems: 1 + + assigned-clocks-parents: + maxItems: 1 + +required: + - compatible + - reg + - clocks + - power-domains + +examples: + - | + /* + * RTI WDT in main domain on J721e SoC. Assigned clocks are used to + * select the source clock for the watchdog, forcing it to tick with + * a 32kHz clock in this case. + */ + #include <dt-bindings/soc/ti,sci_pm_domain.h> + + watchdog0: rti@2200000 { + compatible = "ti,rti-wdt"; + reg = <0x0 0x2200000 0x0 0x100>; + clocks = <&k3_clks 252 1>; + power-domains = <&k3_pds 252 TI_SCI_PD_EXCLUSIVE>; + assigned-clocks = <&k3_clks 252 1>; + assigned-clock-parents = <&k3_clks 252 5>; + }; diff --git a/Documentation/driver-api/usb/writing_usb_driver.rst b/Documentation/driver-api/usb/writing_usb_driver.rst index 4fe1c06b6a13..0b3d9ff221bb 100644 --- a/Documentation/driver-api/usb/writing_usb_driver.rst +++ b/Documentation/driver-api/usb/writing_usb_driver.rst @@ -314,11 +314,8 @@ http://www.linux-usb.org/ Linux Hotplug Project: http://linux-hotplug.sourceforge.net/ -Linux USB Working Devices List: -http://www.qbik.ch/usb/devices/ - -linux-usb-devel Mailing List Archives: -http://marc.theaimsgroup.com/?l=linux-usb-devel +linux-usb Mailing List Archives: +https://lore.kernel.org/linux-usb/ Programming Guide for Linux USB Device Drivers: http://lmu.web.psi.ch/docu/manuals/software_manuals/linux_sl/usb_linux_programming_guide.pdf diff --git a/Documentation/driver-api/w1.rst b/Documentation/driver-api/w1.rst index 9963cca788a1..bda3ad60f655 100644 --- a/Documentation/driver-api/w1.rst +++ b/Documentation/driver-api/w1.rst @@ -7,9 +7,6 @@ W1: Dallas' 1-wire bus W1 API internal to the kernel ============================= -W1 API internal to the kernel ------------------------------ - include/linux/w1.h ~~~~~~~~~~~~~~~~~~ diff --git a/Documentation/filesystems/9p.rst b/Documentation/filesystems/9p.rst index f054d1c45e86..671fef39a802 100644 --- a/Documentation/filesystems/9p.rst +++ b/Documentation/filesystems/9p.rst @@ -158,6 +158,16 @@ Options /sys/fs/9p/caches. (applies only to cache=fscache) ============= =============================================================== +Behavior +======== + +This section aims at describing 9p 'quirks' that can be different +from a local filesystem behaviors. + + - Setting O_NONBLOCK on a file will make client reads return as early + as the server returns some data instead of trying to fill the read + buffer with the requested amount of bytes or end of file is reached. + Resources ========= diff --git a/Documentation/filesystems/ceph.rst b/Documentation/filesystems/ceph.rst index b46a7218248f..0aa70750df0f 100644 --- a/Documentation/filesystems/ceph.rst +++ b/Documentation/filesystems/ceph.rst @@ -107,17 +107,17 @@ Mount Options address its connection to the monitor originates from. wsize=X - Specify the maximum write size in bytes. Default: 16 MB. + Specify the maximum write size in bytes. Default: 64 MB. rsize=X - Specify the maximum read size in bytes. Default: 16 MB. + Specify the maximum read size in bytes. Default: 64 MB. rasize=X Specify the maximum readahead size in bytes. Default: 8 MB. mount_timeout=X Specify the timeout value for mount (in seconds), in the case - of a non-responsive Ceph file system. The default is 30 + of a non-responsive Ceph file system. The default is 60 seconds. caps_max=X diff --git a/Documentation/filesystems/orangefs.rst b/Documentation/filesystems/orangefs.rst index 7d6d4cad73c4..e41369709c5b 100644 --- a/Documentation/filesystems/orangefs.rst +++ b/Documentation/filesystems/orangefs.rst @@ -41,16 +41,6 @@ Documentation http://www.orangefs.org/documentation/ - -Userspace Filesystem Source -=========================== - -http://www.orangefs.org/download - -Orangefs versions prior to 2.9.3 would not be compatible with the -upstream version of the kernel client. - - Running ORANGEFS On a Single Server =================================== @@ -94,6 +84,14 @@ Mount the filesystem:: mount -t pvfs2 tcp://localhost:3334/orangefs /pvfsmnt +Userspace Filesystem Source +=========================== + +http://www.orangefs.org/download + +Orangefs versions prior to 2.9.3 would not be compatible with the +upstream version of the kernel client. + Building ORANGEFS on a Single Server ==================================== @@ -107,18 +105,24 @@ default, we will probably be changing the default to LMDB soon. :: - ./configure --prefix=/opt/ofs --with-db-backend=lmdb + ./configure --prefix=/opt/ofs --with-db-backend=lmdb --disable-usrint make make install -Create an orangefs config file:: +Create an orangefs config file by running pvfs2-genconfig and +specifying a target config file. Pvfs2-genconfig will prompt you +through. Generally it works fine to take the defaults, but you +should use your server's hostname, rather than "localhost" when +it comes to that question:: /opt/ofs/bin/pvfs2-genconfig /etc/pvfs2.conf Create an /etc/pvfs2tab file:: +Localhost is fine for your pvfs2tab file: + echo tcp://localhost:3334/orangefs /pvfsmnt pvfs2 defaults,noauto 0 0 > \ /etc/pvfs2tab @@ -132,7 +136,7 @@ Bootstrap the server:: Start the server:: - /opt/osf/sbin/pvfs2-server /etc/pvfs2.conf + /opt/ofs/sbin/pvfs2-server /etc/pvfs2.conf Now the server should be running. Pvfs2-ls is a simple test to verify that the server is running:: @@ -142,11 +146,11 @@ test to verify that the server is running:: If stuff seems to be working, load the kernel module and turn on the client core:: - /opt/ofs/sbin/pvfs2-client -p /opt/osf/sbin/pvfs2-client-core + /opt/ofs/sbin/pvfs2-client -p /opt/ofs/sbin/pvfs2-client-core Mount your filesystem:: - mount -t pvfs2 tcp://localhost:3334/orangefs /pvfsmnt + mount -t pvfs2 tcp://`hostname`:3334/orangefs /pvfsmnt Running xfstests diff --git a/Documentation/filesystems/overlayfs.rst b/Documentation/filesystems/overlayfs.rst index e443be7928db..c9d2bf96b02d 100644 --- a/Documentation/filesystems/overlayfs.rst +++ b/Documentation/filesystems/overlayfs.rst @@ -40,13 +40,46 @@ On 64bit systems, even if all overlay layers are not on the same underlying filesystem, the same compliant behavior could be achieved with the "xino" feature. The "xino" feature composes a unique object identifier from the real object st_ino and an underlying fsid index. + If all underlying filesystems support NFS file handles and export file handles with 32bit inode number encoding (e.g. ext4), overlay filesystem will use the high inode number bits for fsid. Even when the underlying filesystem uses 64bit inode numbers, users can still enable the "xino" feature with the "-o xino=on" overlay mount option. That is useful for the case of underlying filesystems like xfs and tmpfs, which use 64bit inode -numbers, but are very unlikely to use the high inode number bit. +numbers, but are very unlikely to use the high inode number bits. In case +the underlying inode number does overflow into the high xino bits, overlay +filesystem will fall back to the non xino behavior for that inode. + +The following table summarizes what can be expected in different overlay +configurations. + +Inode properties +```````````````` + ++--------------+------------+------------+-----------------+----------------+ +|Configuration | Persistent | Uniform | st_ino == d_ino | d_ino == i_ino | +| | st_ino | st_dev | | [*] | ++==============+=====+======+=====+======+========+========+========+=======+ +| | dir | !dir | dir | !dir | dir + !dir | dir | !dir | ++--------------+-----+------+-----+------+--------+--------+--------+-------+ +| All layers | Y | Y | Y | Y | Y | Y | Y | Y | +| on same fs | | | | | | | | | ++--------------+-----+------+-----+------+--------+--------+--------+-------+ +| Layers not | N | Y | Y | N | N | Y | N | Y | +| on same fs, | | | | | | | | | +| xino=off | | | | | | | | | ++--------------+-----+------+-----+------+--------+--------+--------+-------+ +| xino=on/auto | Y | Y | Y | Y | Y | Y | Y | Y | +| | | | | | | | | | ++--------------+-----+------+-----+------+--------+--------+--------+-------+ +| xino=on/auto,| N | Y | Y | N | N | Y | N | Y | +| ino overflow | | | | | | | | | ++--------------+-----+------+-----+------+--------+--------+--------+-------+ + +[*] nfsd v3 readdirplus verifies d_ino == i_ino. i_ino is exposed via several +/proc files, such as /proc/locks and /proc/self/fdinfo/<fd> of an inotify +file descriptor. Upper and Lower @@ -248,6 +281,50 @@ overlay filesystem (though an operation on the name of the file such as rename or unlink will of course be noticed and handled). +Permission model +---------------- + +Permission checking in the overlay filesystem follows these principles: + + 1) permission check SHOULD return the same result before and after copy up + + 2) task creating the overlay mount MUST NOT gain additional privileges + + 3) non-mounting task MAY gain additional privileges through the overlay, + compared to direct access on underlying lower or upper filesystems + +This is achieved by performing two permission checks on each access + + a) check if current task is allowed access based on local DAC (owner, + group, mode and posix acl), as well as MAC checks + + b) check if mounting task would be allowed real operation on lower or + upper layer based on underlying filesystem permissions, again including + MAC checks + +Check (a) ensures consistency (1) since owner, group, mode and posix acls +are copied up. On the other hand it can result in server enforced +permissions (used by NFS, for example) being ignored (3). + +Check (b) ensures that no task gains permissions to underlying layers that +the mounting task does not have (2). This also means that it is possible +to create setups where the consistency rule (1) does not hold; normally, +however, the mounting task will have sufficient privileges to perform all +operations. + +Another way to demonstrate this model is drawing parallels between + + mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,... /merged + +and + + cp -a /lower /upper + mount --bind /upper /merged + +The resulting access permissions should be the same. The difference is in +the time of copy (on-demand vs. up-front). + + Multiple lower layers --------------------- @@ -383,7 +460,8 @@ guarantee that the values of st_ino and st_dev returned by stat(2) and the value of d_ino returned by readdir(3) will act like on a normal filesystem. E.g. the value of st_dev may be different for two objects in the same overlay filesystem and the value of st_ino for directory objects may not be -persistent and could change even while the overlay filesystem is mounted. +persistent and could change even while the overlay filesystem is mounted, as +summarized in the `Inode properties`_ table above. Changes to underlying filesystems diff --git a/Documentation/filesystems/qnx6.rst b/Documentation/filesystems/qnx6.rst index b71308314070..fd13433d362c 100644 --- a/Documentation/filesystems/qnx6.rst +++ b/Documentation/filesystems/qnx6.rst @@ -185,7 +185,7 @@ tree structures are treated as system blocks. The rational behind that is that a write request can work on a new snapshot (system area of the inactive - resp. lower serial numbered superblock) while -at the same time there is still a complete stable filesystem structer in the +at the same time there is still a complete stable filesystem structure in the other half of the system area. When finished with writing (a sync write is completed, the maximum sync leap diff --git a/Documentation/firmware-guide/acpi/namespace.rst b/Documentation/firmware-guide/acpi/namespace.rst index 3eb763d6656d..6193582a2204 100644 --- a/Documentation/firmware-guide/acpi/namespace.rst +++ b/Documentation/firmware-guide/acpi/namespace.rst @@ -56,13 +56,13 @@ are illustrated in the following diagram:: +- - - -+ | +-------------------| | | Entry | - - - - - - - -+ | | Definition Blocks | | +- - - -+ | | +-------------------+ | - | | +- - - - - - - - - -+ | - +-|->| SSDT | | + | | +- - - - - - - - - -+ | + +-|->| SSDT | | | +-------------------+ | | | Definition Blocks | | | +- - - - - - - - - -+ | +------------------------+ - | + | OSPM Loading | \|/ +----------------+ diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst index 510f38d7e78a..2d1fc03d346e 100644 --- a/Documentation/kbuild/kbuild.rst +++ b/Documentation/kbuild/kbuild.rst @@ -262,3 +262,8 @@ KBUILD_BUILD_USER, KBUILD_BUILD_HOST These two variables allow to override the user@host string displayed during boot and in /proc/version. The default value is the output of the commands whoami and host, respectively. + +LLVM +---- +If this variable is set to 1, Kbuild will use Clang and LLVM utilities instead +of GCC and GNU binutils to build the kernel. diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst index d6c79eb4e23e..c776b6eee969 100644 --- a/Documentation/kbuild/llvm.rst +++ b/Documentation/kbuild/llvm.rst @@ -47,14 +47,21 @@ example: LLVM Utilities -------------- -LLVM has substitutes for GNU binutils utilities. These can be invoked as -additional parameters to `make`. +LLVM has substitutes for GNU binutils utilities. Kbuild supports `LLVM=1` +to enable them. - make CC=clang AS=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\ - OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-objsize \\ + make LLVM=1 + +They can be enabled individually. The full list of the parameters: + + make CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\ + OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-size \\ READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \\ HOSTLD=ld.lld +Currently, the integrated assembler is disabled by default. You can pass +`LLVM_IAS=1` to enable it. + Getting Help ------------ diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst index e47863575917..91c5ff8e161e 100644 --- a/Documentation/process/changes.rst +++ b/Documentation/process/changes.rst @@ -31,7 +31,7 @@ you probably needn't concern yourself with pcmciautils. ====================== =============== ======================================== GNU C 4.6 gcc --version GNU make 3.81 make --version -binutils 2.21 ld -v +binutils 2.23 ld -v flex 2.5.35 flex --version bison 2.0 bison --version util-linux 2.10o fdformat --version @@ -76,7 +76,7 @@ You will need GNU make 3.81 or later to build the kernel. Binutils -------- -Binutils 2.21 or newer is needed to build the kernel. +Binutils 2.23 or newer is needed to build the kernel. pkg-config ---------- |