diff options
Diffstat (limited to 'Documentation/admin-guide')
| -rw-r--r-- | Documentation/admin-guide/README.rst | 5 | ||||
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 34 | ||||
| -rw-r--r-- | Documentation/admin-guide/mono.rst | 6 | ||||
| -rw-r--r-- | Documentation/admin-guide/thunderbolt.rst | 66 |
4 files changed, 64 insertions, 47 deletions
diff --git a/Documentation/admin-guide/README.rst b/Documentation/admin-guide/README.rst index 63066db39910..af5a437198d0 100644 --- a/Documentation/admin-guide/README.rst +++ b/Documentation/admin-guide/README.rst @@ -170,11 +170,6 @@ Configuring the kernel your existing ./.config file and asking about new config symbols. - "make silentoldconfig" - Like above, but avoids cluttering the screen - with questions already answered. - Additionally updates the dependencies. - "make olddefconfig" Like above, but sets new symbols to their default values without prompting. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index b98048b56ada..1d1d53f85ddd 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -646,6 +646,20 @@ console=brl,ttyS0 For now, only VisioBraille is supported. + console_msg_format= + [KNL] Change console messages format + default + By default we print messages on consoles in + "[time stamp] text\n" format (time stamp may not be + printed, depending on CONFIG_PRINTK_TIME or + `printk_time' param). + syslog + Switch to syslog format: "<%u>[time stamp] text\n" + IOW, each message will have a facility and loglevel + prefix. The format is similar to one used by syslog() + syscall, or to executing "dmesg -S --raw" or to reading + from /proc/kmsg. + consoleblank= [KNL] The console blank (screen saver) timeout in seconds. A value of 0 disables the blank timer. Defaults to 0. @@ -917,9 +931,12 @@ earlycon= [KNL] Output early console device and options. - When used with no options, the early console is - determined by the stdout-path property in device - tree's chosen node. + [ARM64] The early console is determined by the + stdout-path property in device tree's chosen node, + or determined by the ACPI SPCR table. + + [X86] When used with no options the early console is + determined by the ACPI SPCR table. cdns,<addr>[,options] Start an early, polled-mode console on a Cadence @@ -2538,6 +2555,9 @@ This is useful when you use a panic=... timeout and need the box quickly up again. + These settings can be accessed at runtime via + the nmi_watchdog and hardlockup_panic sysctls. + netpoll.carrier_timeout= [NET] Specifies amount of time (in seconds) that netpoll should wait for a carrier. By default netpoll @@ -2741,8 +2761,6 @@ norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space - noreplace-paravirt [X86,IA-64,PV_OPS] Don't patch paravirt_ops - noreplace-smp [X86-32,SMP] Don't replace SMP instructions with UP alternatives @@ -3696,7 +3714,11 @@ [KNL, SMP] Set scheduler's default relax_domain_level. See Documentation/cgroup-v1/cpusets.txt. - reserve= [KNL,BUGS] Force the kernel to ignore some iomem area + reserve= [KNL,BUGS] Force kernel to ignore I/O ports or memory + Format: <base1>,<size1>[,<base2>,<size2>,...] + Reserve I/O ports or memory so the kernel won't use + them. If <base> is less than 0x10000, the region + is assumed to be I/O ports; otherwise it is memory. reservetop= [X86-32] Format: nn[KMG] diff --git a/Documentation/admin-guide/mono.rst b/Documentation/admin-guide/mono.rst index cdddc099af64..59e6d59f0ed9 100644 --- a/Documentation/admin-guide/mono.rst +++ b/Documentation/admin-guide/mono.rst @@ -9,14 +9,14 @@ This will allow you to execute Mono-based .NET binaries just like any other program after you have done the following: 1) You MUST FIRST install the Mono CLR support, either by downloading - a binary package, a source tarball or by installing from CVS. Binary + a binary package, a source tarball or by installing from Git. Binary packages for several distributions can be found at: - http://go-mono.com/download.html + http://www.mono-project.com/download/ Instructions for compiling Mono can be found at: - http://www.go-mono.com/compiling.html + http://www.mono-project.com/docs/compiling-mono/linux/ Once the Mono CLR support has been installed, just check that ``/usr/bin/mono`` (which could be located elsewhere, for example diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst index 9b55952039a6..9948ec36a204 100644 --- a/Documentation/admin-guide/thunderbolt.rst +++ b/Documentation/admin-guide/thunderbolt.rst @@ -3,13 +3,13 @@ ============= The interface presented here is not meant for end users. Instead there should be a userspace tool that handles all the low-level details, keeps -database of the authorized devices and prompts user for new connections. +a database of the authorized devices and prompts users for new connections. More details about the sysfs interface for Thunderbolt devices can be found in ``Documentation/ABI/testing/sysfs-bus-thunderbolt``. Those users who just want to connect any device without any sort of -manual work, can add following line to +manual work can add following line to ``/etc/udev/rules.d/99-local.rules``:: ACTION=="add", SUBSYSTEM=="thunderbolt", ATTR{authorized}=="0", ATTR{authorized}="1" @@ -20,7 +20,7 @@ vulnerable to DMA attacks. Security levels and how to use them ----------------------------------- -Starting from Intel Falcon Ridge Thunderbolt controller there are 4 +Starting with Intel Falcon Ridge Thunderbolt controller there are 4 security levels available. The reason for these is the fact that the connected devices can be DMA masters and thus read contents of the host memory without CPU and OS knowing about it. There are ways to prevent @@ -37,14 +37,14 @@ The security levels are as follows: user User is asked whether the device is allowed to be connected. Based on the device identification information available through - ``/sys/bus/thunderbolt/devices``. user then can do the decision. + ``/sys/bus/thunderbolt/devices``, the user then can make the decision. In BIOS settings this is typically called *Unique ID*. secure User is asked whether the device is allowed to be connected. In addition to UUID the device (if it supports secure connect) is sent a challenge that should match the expected one based on a random key - written to ``key`` sysfs attribute. In BIOS settings this is + written to the ``key`` sysfs attribute. In BIOS settings this is typically called *One time saved key*. dponly @@ -78,7 +78,7 @@ When a device is plugged in it will appear in sysfs as follows:: /sys/bus/thunderbolt/devices/0-1/unique_id - e0376f00-0300-0100-ffff-ffffffffffff The ``authorized`` attribute reads 0 which means no PCIe tunnels are -created yet. The user can authorize the device by simply:: +created yet. The user can authorize the device by simply entering:: # echo 1 > /sys/bus/thunderbolt/devices/0-1/authorized @@ -86,7 +86,7 @@ This will create the PCIe tunnels and the device is now connected. If the device supports secure connect, and the domain security level is set to ``secure``, it has an additional attribute ``key`` which can hold -a random 32 byte value used for authorization and challenging the device in +a random 32-byte value used for authorization and challenging the device in future connects:: /sys/bus/thunderbolt/devices/0-3/authorized - 0 @@ -99,12 +99,12 @@ future connects:: Notice the key is empty by default. -If the user does not want to use secure connect it can just ``echo 1`` +If the user does not want to use secure connect they can just ``echo 1`` to the ``authorized`` attribute and the PCIe tunnels will be created in -the same way than in ``user`` security level. +the same way as in the ``user`` security level. If the user wants to use secure connect, the first time the device is -plugged a key needs to be created and send to the device:: +plugged a key needs to be created and sent to the device:: # key=$(openssl rand -hex 32) # echo $key > /sys/bus/thunderbolt/devices/0-3/key @@ -121,27 +121,27 @@ device using the same key:: If the challenge the device returns back matches the one we expect based on the key, the device is connected and the PCIe tunnels are created. -However, if the challenge failed no tunnels are created and error is +However, if the challenge fails no tunnels are created and error is returned to the user. -If the user still wants to connect the device it can either approve -the device without a key or write new key and write 1 to the +If the user still wants to connect the device they can either approve +the device without a key or write a new key and write 1 to the ``authorized`` file to get the new key stored on the device NVM. Upgrading NVM on Thunderbolt device or host ------------------------------------------- -Since most of the functionality is handled in a firmware running on a +Since most of the functionality is handled in firmware running on a host controller or a device, it is important that the firmware can be upgraded to the latest where possible bugs in it have been fixed. Typically OEMs provide this firmware from their support site. -There is also a central site which has links where to download firmwares +There is also a central site which has links where to download firmware for some machines: `Thunderbolt Updates <https://thunderbolttechnology.net/updates>`_ -Before you upgrade firmware on a device or host, please make sure it is -the suitable. Failing to do that may render the device (or host) in a +Before you upgrade firmware on a device or host, please make sure it is a +suitable upgrade. Failing to do that may render the device (or host) in a state where it cannot be used properly anymore without special tools! Host NVM upgrade on Apple Macs is not supported. @@ -151,7 +151,7 @@ Thunderbolt device so that the host controller appears. It does not matter which device is connected (unless you are upgrading NVM on a device - then you need to connect that particular device). -Note OEM-specific method to power the controller up ("force power") may +Note an OEM-specific method to power the controller up ("force power") may be available for your system in which case there is no need to plug in a Thunderbolt device. @@ -171,7 +171,7 @@ it comes back the driver notices it and initiates a full power cycle. After a while the host controller appears again and this time it should be fully functional. -We can verify that the new NVM firmware is active by running following +We can verify that the new NVM firmware is active by running the following commands:: # cat /sys/bus/thunderbolt/devices/0-0/nvm_authenticate @@ -179,38 +179,38 @@ commands:: # cat /sys/bus/thunderbolt/devices/0-0/nvm_version 18.0 -If ``nvm_authenticate`` contains anything else than 0x0 it is the error +If ``nvm_authenticate`` contains anything other than 0x0 it is the error code from the last authentication cycle, which means the authentication of the NVM image failed. Note names of the NVMem devices ``nvm_activeN`` and ``nvm_non_activeN`` -depends on the order they are registered in the NVMem subsystem. N in +depend on the order they are registered in the NVMem subsystem. N in the name is the identifier added by the NVMem subsystem. Upgrading NVM when host controller is in safe mode -------------------------------------------------- If the existing NVM is not properly authenticated (or is missing) the -host controller goes into safe mode which means that only available -functionality is flashing new NVM image. When in this mode the reading +host controller goes into safe mode which means that the only available +functionality is flashing a new NVM image. When in this mode, reading ``nvm_version`` fails with ``ENODATA`` and the device identification information is missing. To recover from this mode, one needs to flash a valid NVM image to the -host host controller in the same way it is done in the previous chapter. +host controller in the same way it is done in the previous chapter. Networking over Thunderbolt cable --------------------------------- -Thunderbolt technology allows software communication across two hosts +Thunderbolt technology allows software communication between two hosts connected by a Thunderbolt cable. -It is possible to tunnel any kind of traffic over Thunderbolt link but +It is possible to tunnel any kind of traffic over a Thunderbolt link but currently we only support Apple ThunderboltIP protocol. -If the other host is running Windows or macOS only thing you need to -do is to connect Thunderbolt cable between the two hosts, the -``thunderbolt-net`` is loaded automatically. If the other host is also -Linux you should load ``thunderbolt-net`` manually on one host (it does -not matter which one):: +If the other host is running Windows or macOS, the only thing you need to +do is to connect a Thunderbolt cable between the two hosts; the +``thunderbolt-net`` driver is loaded automatically. If the other host is +also Linux you should load ``thunderbolt-net`` manually on one host (it +does not matter which one):: # modprobe thunderbolt-net @@ -220,12 +220,12 @@ is built-in to the kernel image, there is no need to do anything. The driver will create one virtual ethernet interface per Thunderbolt port which are named like ``thunderbolt0`` and so on. From this point you can either use standard userspace tools like ``ifconfig`` to -configure the interface or let your GUI to handle it automatically. +configure the interface or let your GUI handle it automatically. Forcing power ------------- Many OEMs include a method that can be used to force the power of a -thunderbolt controller to an "On" state even if nothing is connected. +Thunderbolt controller to an "On" state even if nothing is connected. If supported by your machine this will be exposed by the WMI bus with a sysfs attribute called "force_power". |