diff options
Diffstat (limited to 'Documentation/admin-guide')
36 files changed, 550 insertions, 209 deletions
diff --git a/Documentation/admin-guide/LSM/index.rst b/Documentation/admin-guide/LSM/index.rst index ce63be6d64ad..b44ef68f6e4d 100644 --- a/Documentation/admin-guide/LSM/index.rst +++ b/Documentation/admin-guide/LSM/index.rst @@ -48,3 +48,4 @@ subdirectories. Yama SafeSetID ipe + landlock diff --git a/Documentation/admin-guide/LSM/landlock.rst b/Documentation/admin-guide/LSM/landlock.rst new file mode 100644 index 000000000000..9e61607def08 --- /dev/null +++ b/Documentation/admin-guide/LSM/landlock.rst @@ -0,0 +1,158 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. Copyright © 2025 Microsoft Corporation + +================================ +Landlock: system-wide management +================================ + +:Author: Mickaël Salaün +:Date: March 2025 + +Landlock can leverage the audit framework to log events. + +User space documentation can be found here: +Documentation/userspace-api/landlock.rst. + +Audit +===== + +Denied access requests are logged by default for a sandboxed program if `audit` +is enabled. This default behavior can be changed with the +sys_landlock_restrict_self() flags (cf. +Documentation/userspace-api/landlock.rst). Landlock logs can also be masked +thanks to audit rules. Landlock can generate 2 audit record types. + +Record types +------------ + +AUDIT_LANDLOCK_ACCESS + This record type identifies a denied access request to a kernel resource. + The ``domain`` field indicates the ID of the domain that blocked the + request. The ``blockers`` field indicates the cause(s) of this denial + (separated by a comma), and the following fields identify the kernel object + (similar to SELinux). There may be more than one of this record type per + audit event. + + Example with a file link request generating two records in the same event:: + + domain=195ba459b blockers=fs.refer path="/usr/bin" dev="vda2" ino=351 + domain=195ba459b blockers=fs.make_reg,fs.refer path="/usr/local" dev="vda2" ino=365 + +AUDIT_LANDLOCK_DOMAIN + This record type describes the status of a Landlock domain. The ``status`` + field can be either ``allocated`` or ``deallocated``. + + The ``allocated`` status is part of the same audit event and follows + the first logged ``AUDIT_LANDLOCK_ACCESS`` record of a domain. It identifies + Landlock domain information at the time of the sys_landlock_restrict_self() + call with the following fields: + + - the ``domain`` ID + - the enforcement ``mode`` + - the domain creator's ``pid`` + - the domain creator's ``uid`` + - the domain creator's executable path (``exe``) + - the domain creator's command line (``comm``) + + Example:: + + domain=195ba459b status=allocated mode=enforcing pid=300 uid=0 exe="/root/sandboxer" comm="sandboxer" + + The ``deallocated`` status is an event on its own and it identifies a + Landlock domain release. After such event, it is guarantee that the + related domain ID will never be reused during the lifetime of the system. + The ``domain`` field indicates the ID of the domain which is released, and + the ``denials`` field indicates the total number of denied access request, + which might not have been logged according to the audit rules and + sys_landlock_restrict_self()'s flags. + + Example:: + + domain=195ba459b status=deallocated denials=3 + + +Event samples +-------------- + +Here are two examples of log events (see serial numbers). + +In this example a sandboxed program (``kill``) tries to send a signal to the +init process, which is denied because of the signal scoping restriction +(``LL_SCOPED=s``):: + + $ LL_FS_RO=/ LL_FS_RW=/ LL_SCOPED=s LL_FORCE_LOG=1 ./sandboxer kill 1 + +This command generates two events, each identified with a unique serial +number following a timestamp (``msg=audit(1729738800.268:30)``). The first +event (serial ``30``) contains 4 records. The first record +(``type=LANDLOCK_ACCESS``) shows an access denied by the domain `1a6fdc66f`. +The cause of this denial is signal scopping restriction +(``blockers=scope.signal``). The process that would have receive this signal +is the init process (``opid=1 ocomm="systemd"``). + +The second record (``type=LANDLOCK_DOMAIN``) describes (``status=allocated``) +domain `1a6fdc66f`. This domain was created by process ``286`` executing the +``/root/sandboxer`` program launched by the root user. + +The third record (``type=SYSCALL``) describes the syscall, its provided +arguments, its result (``success=no exit=-1``), and the process that called it. + +The fourth record (``type=PROCTITLE``) shows the command's name as an +hexadecimal value. This can be translated with ``python -c +'print(bytes.fromhex("6B696C6C0031"))'``. + +Finally, the last record (``type=LANDLOCK_DOMAIN``) is also the only one from +the second event (serial ``31``). It is not tied to a direct user space action +but an asynchronous one to free resources tied to a Landlock domain +(``status=deallocated``). This can be useful to know that the following logs +will not concern the domain ``1a6fdc66f`` anymore. This record also summarize +the number of requests this domain denied (``denials=1``), whether they were +logged or not. + +.. code-block:: + + type=LANDLOCK_ACCESS msg=audit(1729738800.268:30): domain=1a6fdc66f blockers=scope.signal opid=1 ocomm="systemd" + type=LANDLOCK_DOMAIN msg=audit(1729738800.268:30): domain=1a6fdc66f status=allocated mode=enforcing pid=286 uid=0 exe="/root/sandboxer" comm="sandboxer" + type=SYSCALL msg=audit(1729738800.268:30): arch=c000003e syscall=62 success=no exit=-1 [..] ppid=272 pid=286 auid=0 uid=0 gid=0 [...] comm="kill" [...] + type=PROCTITLE msg=audit(1729738800.268:30): proctitle=6B696C6C0031 + type=LANDLOCK_DOMAIN msg=audit(1729738800.324:31): domain=1a6fdc66f status=deallocated denials=1 + +Here is another example showcasing filesystem access control:: + + $ LL_FS_RO=/ LL_FS_RW=/tmp LL_FORCE_LOG=1 ./sandboxer sh -c "echo > /etc/passwd" + +The related audit logs contains 8 records from 3 different events (serials 33, +34 and 35) created by the same domain `1a6fdc679`:: + + type=LANDLOCK_ACCESS msg=audit(1729738800.221:33): domain=1a6fdc679 blockers=fs.write_file path="/dev/tty" dev="devtmpfs" ino=9 + type=LANDLOCK_DOMAIN msg=audit(1729738800.221:33): domain=1a6fdc679 status=allocated mode=enforcing pid=289 uid=0 exe="/root/sandboxer" comm="sandboxer" + type=SYSCALL msg=audit(1729738800.221:33): arch=c000003e syscall=257 success=no exit=-13 [...] ppid=272 pid=289 auid=0 uid=0 gid=0 [...] comm="sh" [...] + type=PROCTITLE msg=audit(1729738800.221:33): proctitle=7368002D63006563686F203E202F6574632F706173737764 + type=LANDLOCK_ACCESS msg=audit(1729738800.221:34): domain=1a6fdc679 blockers=fs.write_file path="/etc/passwd" dev="vda2" ino=143821 + type=SYSCALL msg=audit(1729738800.221:34): arch=c000003e syscall=257 success=no exit=-13 [...] ppid=272 pid=289 auid=0 uid=0 gid=0 [...] comm="sh" [...] + type=PROCTITLE msg=audit(1729738800.221:34): proctitle=7368002D63006563686F203E202F6574632F706173737764 + type=LANDLOCK_DOMAIN msg=audit(1729738800.261:35): domain=1a6fdc679 status=deallocated denials=2 + + +Event filtering +--------------- + +If you get spammed with audit logs related to Landlock, this is either an +attack attempt or a bug in the security policy. We can put in place some +filters to limit noise with two complementary ways: + +- with sys_landlock_restrict_self()'s flags if we can fix the sandboxed + programs, +- or with audit rules (see :manpage:`auditctl(8)`). + +Additional documentation +======================== + +* `Linux Audit Documentation`_ +* Documentation/userspace-api/landlock.rst +* Documentation/security/landlock.rst +* https://landlock.io + +.. Links +.. _Linux Audit Documentation: + https://github.com/linux-audit/audit-documentation/wiki diff --git a/Documentation/admin-guide/README.rst b/Documentation/admin-guide/README.rst index b557cf1c820d..70b02f30013a 100644 --- a/Documentation/admin-guide/README.rst +++ b/Documentation/admin-guide/README.rst @@ -165,7 +165,7 @@ Configuring the kernel "make xconfig" Qt based configuration tool. - "make gconfig" GTK+ based configuration tool. + "make gconfig" GTK based configuration tool. "make oldconfig" Default all questions based on the contents of your existing ./.config file and asking about diff --git a/Documentation/admin-guide/abi-obsolete-files.rst b/Documentation/admin-guide/abi-obsolete-files.rst new file mode 100644 index 000000000000..3061a916b4b5 --- /dev/null +++ b/Documentation/admin-guide/abi-obsolete-files.rst @@ -0,0 +1,7 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Obsolete ABI Files +================== + +.. kernel-abi:: obsolete + :no-symbols: diff --git a/Documentation/admin-guide/abi-obsolete.rst b/Documentation/admin-guide/abi-obsolete.rst index 594e697aa1b2..640f3903e847 100644 --- a/Documentation/admin-guide/abi-obsolete.rst +++ b/Documentation/admin-guide/abi-obsolete.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ABI obsolete symbols ==================== @@ -7,5 +9,5 @@ marked to be removed at some later point in time. The description of the interface will document the reason why it is obsolete and when it can be expected to be removed. -.. kernel-abi:: ABI/obsolete - :rst: +.. kernel-abi:: obsolete + :no-files: diff --git a/Documentation/admin-guide/abi-removed-files.rst b/Documentation/admin-guide/abi-removed-files.rst new file mode 100644 index 000000000000..f1bdfadd2ec4 --- /dev/null +++ b/Documentation/admin-guide/abi-removed-files.rst @@ -0,0 +1,7 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Removed ABI Files +================= + +.. kernel-abi:: removed + :no-symbols: diff --git a/Documentation/admin-guide/abi-removed.rst b/Documentation/admin-guide/abi-removed.rst index f9e000c81828..88832d3eacd6 100644 --- a/Documentation/admin-guide/abi-removed.rst +++ b/Documentation/admin-guide/abi-removed.rst @@ -1,5 +1,7 @@ +.. SPDX-License-Identifier: GPL-2.0 + ABI removed symbols =================== -.. kernel-abi:: ABI/removed - :rst: +.. kernel-abi:: removed + :no-files: diff --git a/Documentation/admin-guide/abi-stable-files.rst b/Documentation/admin-guide/abi-stable-files.rst new file mode 100644 index 000000000000..f867738fc178 --- /dev/null +++ b/Documentation/admin-guide/abi-stable-files.rst @@ -0,0 +1,7 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Stable ABI Files +================ + +.. kernel-abi:: stable + :no-symbols: diff --git a/Documentation/admin-guide/abi-stable.rst b/Documentation/admin-guide/abi-stable.rst index fc3361d847b1..528c68401f4b 100644 --- a/Documentation/admin-guide/abi-stable.rst +++ b/Documentation/admin-guide/abi-stable.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ABI stable symbols ================== @@ -10,5 +12,5 @@ for at least 2 years. Most interfaces (like syscalls) are expected to never change and always be available. -.. kernel-abi:: ABI/stable - :rst: +.. kernel-abi:: stable + :no-files: diff --git a/Documentation/admin-guide/abi-testing-files.rst b/Documentation/admin-guide/abi-testing-files.rst new file mode 100644 index 000000000000..1da868e42fdb --- /dev/null +++ b/Documentation/admin-guide/abi-testing-files.rst @@ -0,0 +1,7 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Testing ABI Files +================= + +.. kernel-abi:: testing + :no-symbols: diff --git a/Documentation/admin-guide/abi-testing.rst b/Documentation/admin-guide/abi-testing.rst index 19767926b344..6153ebd38e2d 100644 --- a/Documentation/admin-guide/abi-testing.rst +++ b/Documentation/admin-guide/abi-testing.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ABI testing symbols =================== @@ -16,5 +18,5 @@ Programs that use these interfaces are strongly encouraged to add their name to the description of these interfaces, so that the kernel developers can easily notify them if any changes occur. -.. kernel-abi:: ABI/testing - :rst: +.. kernel-abi:: testing + :no-files: diff --git a/Documentation/admin-guide/abi.rst b/Documentation/admin-guide/abi.rst index bcab3ef2597c..c6039359e585 100644 --- a/Documentation/admin-guide/abi.rst +++ b/Documentation/admin-guide/abi.rst @@ -1,7 +1,14 @@ +.. SPDX-License-Identifier: GPL-2.0 + ===================== Linux ABI description ===================== +.. kernel-abi:: README + +ABI symbols +----------- + .. toctree:: :maxdepth: 2 @@ -9,3 +16,14 @@ Linux ABI description abi-testing abi-obsolete abi-removed + +ABI files +--------- + +.. toctree:: + :maxdepth: 2 + + abi-stable-files + abi-testing-files + abi-obsolete-files + abi-removed-files diff --git a/Documentation/admin-guide/ext4.rst b/Documentation/admin-guide/ext4.rst index 2418b0c2d3df..b857eb6ca1b6 100644 --- a/Documentation/admin-guide/ext4.rst +++ b/Documentation/admin-guide/ext4.rst @@ -238,11 +238,10 @@ When mounting an ext4 filesystem, the following option are accepted: configured using tune2fs) data_err=ignore(*) - Just print an error message if an error occurs in a file data buffer in - ordered mode. + Just print an error message if an error occurs in a file data buffer. + data_err=abort - Abort the journal if an error occurs in a file data buffer in ordered - mode. + Abort the journal if an error occurs in a file data buffer. grpid | bsdgroups New objects have the group ID of their parent. diff --git a/Documentation/admin-guide/gpio/gpio-sim.rst b/Documentation/admin-guide/gpio/gpio-sim.rst index 1cc5567a4bbe..35d49ccd49e0 100644 --- a/Documentation/admin-guide/gpio/gpio-sim.rst +++ b/Documentation/admin-guide/gpio/gpio-sim.rst @@ -71,7 +71,7 @@ specific lines. The name of those subdirectories must take the form of: ``'line<offset>'`` (e.g. ``'line0'``, ``'line20'``, etc.) as the name will be used by the module to assign the config to the specific line at given offset. -Once the confiuration is complete, the ``'live'`` attribute must be set to 1 in +Once the configuration is complete, the ``'live'`` attribute must be set to 1 in order to instantiate the chip. It can be set back to 0 to destroy the simulated chip. The module will synchronously wait for the new simulated device to be successfully probed and if this doesn't happen, writing to ``'live'`` will diff --git a/Documentation/admin-guide/gpio/gpio-virtuser.rst b/Documentation/admin-guide/gpio/gpio-virtuser.rst index 2aca70db9f3b..7e7c0df51640 100644 --- a/Documentation/admin-guide/gpio/gpio-virtuser.rst +++ b/Documentation/admin-guide/gpio/gpio-virtuser.rst @@ -92,7 +92,7 @@ struct. The first two take string values as arguments: Activating GPIO consumers ------------------------- -Once the confiuration is complete, the ``'live'`` attribute must be set to 1 in +Once the configuration is complete, the ``'live'`` attribute must be set to 1 in order to instantiate the consumer. It can be set back to 0 to destroy the virtual device. The module will synchronously wait for the new simulated device to be successfully probed and if this doesn't happen, writing to ``'live'`` will diff --git a/Documentation/admin-guide/highuid.rst b/Documentation/admin-guide/highuid.rst deleted file mode 100644 index 6ee70465c0ea..000000000000 --- a/Documentation/admin-guide/highuid.rst +++ /dev/null @@ -1,80 +0,0 @@ -=================================================== -Notes on the change from 16-bit UIDs to 32-bit UIDs -=================================================== - -:Author: Chris Wing <wingc@umich.edu> -:Last updated: January 11, 2000 - -- kernel code MUST take into account __kernel_uid_t and __kernel_uid32_t - when communicating between user and kernel space in an ioctl or data - structure. - -- kernel code should use uid_t and gid_t in kernel-private structures and - code. - -What's left to be done for 32-bit UIDs on all Linux architectures: - -- Disk quotas have an interesting limitation that is not related to the - maximum UID/GID. They are limited by the maximum file size on the - underlying filesystem, because quota records are written at offsets - corresponding to the UID in question. - Further investigation is needed to see if the quota system can cope - properly with huge UIDs. If it can deal with 64-bit file offsets on all - architectures, this should not be a problem. - -- Decide whether or not to keep backwards compatibility with the system - accounting file, or if we should break it as the comments suggest - (currently, the old 16-bit UID and GID are still written to disk, and - part of the former pad space is used to store separate 32-bit UID and - GID) - -- Need to validate that OS emulation calls the 16-bit UID - compatibility syscalls, if the OS being emulated used 16-bit UIDs, or - uses the 32-bit UID system calls properly otherwise. - - This affects at least: - - - iBCS on Intel - - - sparc32 emulation on sparc64 - (need to support whatever new 32-bit UID system calls are added to - sparc32) - -- Validate that all filesystems behave properly. - - At present, 32-bit UIDs _should_ work for: - - - ext2 - - ufs - - isofs - - nfs - - coda - - udf - - Ioctl() fixups have been made for: - - - ncpfs - - smbfs - - Filesystems with simple fixups to prevent 16-bit UID wraparound: - - - minix - - sysv - - qnx4 - - Other filesystems have not been checked yet. - -- The ncpfs and smpfs filesystems cannot presently use 32-bit UIDs in - all ioctl()s. Some new ioctl()s have been added with 32-bit UIDs, but - more are needed. (as well as new user<->kernel data structures) - -- The ELF core dump format only supports 16-bit UIDs on arm, i386, m68k, - sh, and sparc32. Fixing this is probably not that important, but would - require adding a new ELF section. - -- The ioctl()s used to control the in-kernel NFS server only support - 16-bit UIDs on arm, i386, m68k, sh, and sparc32. - -- make sure that the UID mapping feature of AX25 networking works properly - (it should be safe because it's always used a 32-bit integer to - communicate between user and kernel) diff --git a/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst b/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst index 0585d02b9a6c..ad15417d39f9 100644 --- a/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst +++ b/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst @@ -29,14 +29,6 @@ Below is the list of affected Intel processors [#f1]_: RAPTORLAKE_S 06_BFH =================== ============ -As an exception to this table, Intel Xeon E family parts ALDERLAKE(06_97H) and -RAPTORLAKE(06_B7H) codenamed Catlow are not affected. They are reported as -vulnerable in Linux because they share the same family/model with an affected -part. Unlike their affected counterparts, they do not enumerate RFDS_CLEAR or -CPUID.HYBRID. This information could be used to distinguish between the -affected and unaffected parts, but it is deemed not worth adding complexity as -the reporting is fixed automatically when these parts enumerate RFDS_NO. - Mitigation ========== Intel released a microcode update that enables software to clear sensitive diff --git a/Documentation/admin-guide/hw-vuln/srso.rst b/Documentation/admin-guide/hw-vuln/srso.rst index 2ad1c05b8c88..66af95251a3d 100644 --- a/Documentation/admin-guide/hw-vuln/srso.rst +++ b/Documentation/admin-guide/hw-vuln/srso.rst @@ -104,7 +104,20 @@ The possible values in this file are: (spec_rstack_overflow=ibpb-vmexit) + * 'Mitigation: Reduced Speculation': + This mitigation gets automatically enabled when the above one "IBPB on + VMEXIT" has been selected and the CPU supports the BpSpecReduce bit. + + It gets automatically enabled on machines which have the + SRSO_USER_KERNEL_NO=1 CPUID bit. In that case, the code logic is to switch + to the above =ibpb-vmexit mitigation because the user/kernel boundary is + not affected anymore and thus "safe RET" is not needed. + + After enabling the IBPB on VMEXIT mitigation option, the BpSpecReduce bit + is detected (functionality present on all such machines) and that + practically overrides IBPB on VMEXIT as it has a lot less performance + impact and takes care of the guest->host attack vector too. In order to exploit vulnerability, an attacker needs to: diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst index c8af32a8f800..259d79fbeb94 100644 --- a/Documentation/admin-guide/index.rst +++ b/Documentation/admin-guide/index.rst @@ -187,7 +187,6 @@ A few hard-to-categorize and generally obsolete documents. .. toctree:: :maxdepth: 1 - highuid ldm unicode diff --git a/Documentation/admin-guide/iostats.rst b/Documentation/admin-guide/iostats.rst index 609a3201fd4e..9453196ade51 100644 --- a/Documentation/admin-guide/iostats.rst +++ b/Documentation/admin-guide/iostats.rst @@ -2,62 +2,39 @@ I/O statistics fields ===================== -Since 2.4.20 (and some versions before, with patches), and 2.5.45, -more extensive disk statistics have been introduced to help measure disk -activity. Tools such as ``sar`` and ``iostat`` typically interpret these and do -the work for you, but in case you are interested in creating your own -tools, the fields are explained here. - -In 2.4 now, the information is found as additional fields in -``/proc/partitions``. In 2.6 and upper, the same information is found in two -places: one is in the file ``/proc/diskstats``, and the other is within -the sysfs file system, which must be mounted in order to obtain -the information. Throughout this document we'll assume that sysfs -is mounted on ``/sys``, although of course it may be mounted anywhere. -Both ``/proc/diskstats`` and sysfs use the same source for the information -and so should not differ. - -Here are examples of these different formats:: - - 2.4: - 3 0 39082680 hda 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160 - 3 1 9221278 hda1 35486 0 35496 38030 0 0 0 0 0 38030 38030 - - 2.6+ sysfs: - 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160 - 35486 38030 38030 38030 - - 2.6+ diskstats: - 3 0 hda 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160 - 3 1 hda1 35486 38030 38030 38030 - - 4.18+ diskstats: - 3 0 hda 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160 0 0 0 0 - -On 2.4 you might execute ``grep 'hda ' /proc/partitions``. On 2.6+, you have -a choice of ``cat /sys/block/hda/stat`` or ``grep 'hda ' /proc/diskstats``. - -The advantage of one over the other is that the sysfs choice works well -if you are watching a known, small set of disks. ``/proc/diskstats`` may -be a better choice if you are watching a large number of disks because -you'll avoid the overhead of 50, 100, or 500 or more opens/closes with -each snapshot of your disk statistics. - -In 2.4, the statistics fields are those after the device name. In -the above example, the first field of statistics would be 446216. -By contrast, in 2.6+ if you look at ``/sys/block/hda/stat``, you'll -find just the 15 fields, beginning with 446216. If you look at -``/proc/diskstats``, the 15 fields will be preceded by the major and -minor device numbers, and device name. Each of these formats provides -15 fields of statistics, each meaning exactly the same things. -All fields except field 9 are cumulative since boot. Field 9 should -go to zero as I/Os complete; all others only increase (unless they -overflow and wrap). Wrapping might eventually occur on a very busy -or long-lived system; so applications should be prepared to deal with -it. Regarding wrapping, the types of the fields are either unsigned -int (32 bit) or unsigned long (32-bit or 64-bit, depending on your -machine) as noted per-field below. Unless your observations are very -spread in time, these fields should not wrap twice before you notice it. +The kernel exposes disk statistics via ``/proc/diskstats`` and +``/sys/block/<device>/stat``. These stats are usually accessed via tools +such as ``sar`` and ``iostat``. + +Here are examples using a disk with two partitions:: + + /proc/diskstats: + 259 0 nvme0n1 255999 814 12369153 47919 996852 81 36123024 425995 0 301795 580470 0 0 0 0 60602 106555 + 259 1 nvme0n1p1 492 813 17572 96 848 81 108288 210 0 76 307 0 0 0 0 0 0 + 259 2 nvme0n1p2 255401 1 12343477 47799 996004 0 36014736 425784 0 344336 473584 0 0 0 0 0 0 + + /sys/block/nvme0n1/stat: + 255999 814 12369153 47919 996858 81 36123056 426009 0 301809 580491 0 0 0 0 60605 106562 + + /sys/block/nvme0n1/nvme0n1p1/stat: + 492 813 17572 96 848 81 108288 210 0 76 307 0 0 0 0 0 0 + +Both files contain the same 17 statistics. ``/sys/block/<device>/stat`` +contains the fields for ``<device>``. In ``/proc/diskstats`` the fields +are prefixed with the major and minor device numbers and the device +name. In the example above, the first stat value for ``nvme0n1`` is +255999 in both files. + +The sysfs ``stat`` file is efficient for monitoring a small, known set +of disks. If you're tracking a large number of devices, +``/proc/diskstats`` is often the better choice since it avoids the +overhead of opening and closing multiple files for each snapshot. + +All fields are cumulative, monotonic counters, except for field 9, which +resets to zero as I/Os complete. The remaining fields reset at boot, on +device reattachment or reinitialization, or when the underlying counter +overflows. Applications reading these counters should detect and handle +resets when comparing stat snapshots. Each set of stats only applies to the indicated device; if you want system-wide stats you'll have to find all the devices and sum them all up. diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst index 5376890adbeb..1f7f14c6e184 100644 --- a/Documentation/admin-guide/kdump/kdump.rst +++ b/Documentation/admin-guide/kdump/kdump.rst @@ -180,10 +180,6 @@ Dump-capture kernel config options (Arch Dependent, i386 and x86_64) 1) On i386, enable high memory support under "Processor type and features":: - CONFIG_HIGHMEM64G=y - - or:: - CONFIG_HIGHMEM4G 2) With CONFIG_SMP=y, usually nr_cpus=1 need specified on the kernel diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 41d4cf206ec1..3435a062a208 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -416,10 +416,6 @@ Format: { quiet (default) | verbose | debug } Change the amount of debugging information output when initialising the APIC and IO-APIC components. - For X86-32, this can also be used to specify an APIC - driver name. - Format: apic=driver_name - Examples: apic=bigsmp apic_extnmi= [APIC,X86,EARLY] External NMI delivery setting Format: { bsp (default) | all | none } @@ -1411,14 +1407,21 @@ earlyprintk=serial[,0x...[,baudrate]] earlyprintk=ttySn[,baudrate] earlyprintk=dbgp[debugController#] - earlyprintk=pciserial[,force],bus:device.function[,baudrate] + earlyprintk=pciserial[,force],bus:device.function[,{nocfg|baudrate}] earlyprintk=xdbc[xhciController#] earlyprintk=bios + earlyprintk=mmio,membase[,{nocfg|baudrate}] earlyprintk is useful when the kernel crashes before the normal console is initialized. It is not enabled by default because it has some cosmetic problems. + Only 32-bit memory addresses are supported for "mmio" + and "pciserial" devices. + + Use "nocfg" to skip UART configuration, assume + BIOS/firmware has configured UART correctly. + Append ",keep" to not disable it when the real console takes over. @@ -2318,6 +2321,9 @@ per_cpu_perf_limits Allow per-logical-CPU P-State performance control limits using cpufreq sysfs interface + no_cas + Do not enable capacity-aware scheduling (CAS) on + hybrid systems intremap= [X86-64,Intel-IOMMU,EARLY] on enable Interrupt Remapping (default) @@ -3118,6 +3124,8 @@ * max_sec_lba48: Set or clear transfer size limit to 65535 sectors. + * external: Mark port as external (hotplug-capable). + * [no]lpm: Enable or disable link power management. * [no]setxfer: Indicate if transfer speed mode setting @@ -5019,6 +5027,14 @@ Format: <bool> default: 0 (auto_verbose is enabled) + printk.debug_non_panic_cpus= + Allows storing messages from non-panic CPUs into + the printk log buffer during panic(). They are + flushed to consoles by the panic-CPU on + a best-effort basis. + Format: <bool> (1/Y/y=enable, 0/N/n=disable) + Default: disabled + printk.devkmsg={on,off,ratelimit} Control writing to /dev/kmsg. on - unlimited logging to /dev/kmsg from userspace @@ -5760,6 +5776,11 @@ rcutorture.test_boost_duration= [KNL] Duration (s) of each individual boost test. + rcutorture.test_boost_holdoff= [KNL] + Holdoff time (s) from start of test to the start + of RCU priority-boost testing. Defaults to zero, + that is, no holdoff. + rcutorture.test_boost_interval= [KNL] Interval (s) between each boost test. @@ -6084,7 +6105,7 @@ is assumed to be I/O ports; otherwise it is memory. reserve_mem= [RAM] - Format: nn[KNG]:<align>:<label> + Format: nn[KMG]:<align>:<label> Reserve physical memory and label it with a name that other subsystems can use to access it. This is typically used for systems that do not wipe the RAM, and this command @@ -6584,6 +6605,8 @@ Selecting 'on' will also enable the mitigation against user space to user space task attacks. + Selecting specific mitigation does not force enable + user mitigations. Selecting 'off' will disable both the kernel and the user space protections. @@ -7281,6 +7304,15 @@ See also "Event triggers" in Documentation/trace/events.rst + traceoff_after_boot + [FTRACE] Sometimes tracing is used to debug issues + during the boot process. Since the trace buffer has a + limited amount of storage, it may be prudent to + disable tracing after the boot is finished, otherwise + the critical information may be overwritten. With this + option, the main tracing buffer will be turned off at + the end of the boot process. + traceoff_on_warning [FTRACE] enable this option to disable tracing when a warning is hit. This turns off "tracing_on". Tracing can @@ -7674,13 +7706,6 @@ 16 - SIGBUS faults Example: user_debug=31 - userpte= - [X86,EARLY] Flags controlling user PTE allocations. - - nohigh = do not allocate PTE pages in - HIGHMEM regardless of setting - of CONFIG_HIGHPTE. - vdso= [X86,SH,SPARC] On X86_32, this is an alias for vdso32=. Otherwise: diff --git a/Documentation/admin-guide/kernel-per-CPU-kthreads.rst b/Documentation/admin-guide/kernel-per-CPU-kthreads.rst index ea7fa2a8bbf0..ee9a6c94f383 100644 --- a/Documentation/admin-guide/kernel-per-CPU-kthreads.rst +++ b/Documentation/admin-guide/kernel-per-CPU-kthreads.rst @@ -278,12 +278,7 @@ To reduce its OS jitter, do any of the following: due to the rtas_event_scan() function. WARNING: Please check your CPU specifications to make sure that this is safe on your particular system. - e. If running on Cell Processor, build your kernel with - CBE_CPUFREQ_SPU_GOVERNOR=n to avoid OS jitter from - spu_gov_work(). - WARNING: Please check your CPU specifications to - make sure that this is safe on your particular system. - f. If running on PowerMAC, build your kernel with + e. If running on PowerMAC, build your kernel with CONFIG_PMAC_RACKMETER=n to disable the CPU-meter, avoiding OS jitter from rackmeter_do_timer(). diff --git a/Documentation/admin-guide/laptops/index.rst b/Documentation/admin-guide/laptops/index.rst index cd9a1c2695fd..e71c8984c23e 100644 --- a/Documentation/admin-guide/laptops/index.rst +++ b/Documentation/admin-guide/laptops/index.rst @@ -11,6 +11,7 @@ Laptop Drivers disk-shock-protection laptop-mode lg-laptop + samsung-galaxybook sony-laptop sonypi thinkpad-acpi diff --git a/Documentation/admin-guide/laptops/samsung-galaxybook.rst b/Documentation/admin-guide/laptops/samsung-galaxybook.rst new file mode 100644 index 000000000000..752b8f1a4a74 --- /dev/null +++ b/Documentation/admin-guide/laptops/samsung-galaxybook.rst @@ -0,0 +1,174 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +========================== +Samsung Galaxy Book Driver +========================== + +Joshua Grisham <josh@joshuagrisham.com> + +This is a Linux x86 platform driver for Samsung Galaxy Book series notebook +devices which utilizes Samsung's ``SCAI`` ACPI device in order to control +extra features and receive various notifications. + +Supported devices +================= + +Any device with one of the supported ACPI device IDs should be supported. This +covers most of the "Samsung Galaxy Book" series notebooks that are currently +available as of this writing, and could include other Samsung notebook devices +as well. + +Status +====== + +The following features are currently supported: + +- :ref:`Keyboard backlight <keyboard-backlight>` control +- :ref:`Performance mode <performance-mode>` control implemented using the + platform profile interface +- :ref:`Battery charge control end threshold + <battery-charge-control-end-threshold>` (stop charging battery at given + percentage value) implemented as a battery hook +- :ref:`Firmware Attributes <firmware-attributes>` to allow control of various + device settings +- :ref:`Handling of Fn hotkeys <keyboard-hotkey-actions>` for various actions +- :ref:`Handling of ACPI notifications and hotkeys + <acpi-notifications-and-hotkey-actions>` + +Because different models of these devices can vary in their features, there is +logic built within the driver which attempts to test each implemented feature +for a valid response before enabling its support (registering additional devices +or extensions, adding sysfs attributes, etc). Therefore, it can be important to +note that not all features may be supported for your particular device. + +The following features might be possible to implement but will require +additional investigation and are therefore not supported at this time: + +- "Dolby Atmos" mode for the speakers +- "Outdoor Mode" for increasing screen brightness on models with ``SAM0427`` +- "Silent Mode" on models with ``SAM0427`` + +.. _keyboard-backlight: + +Keyboard backlight +================== + +A new LED class named ``samsung-galaxybook::kbd_backlight`` is created which +will then expose the device using the standard sysfs-based LED interface at +``/sys/class/leds/samsung-galaxybook::kbd_backlight``. Brightness can be +controlled by writing the desired value to the ``brightness`` sysfs attribute or +with any other desired userspace utility. + +.. note:: + Most of these devices have an ambient light sensor which also turns + off the keyboard backlight under well-lit conditions. This behavior does not + seem possible to control at this time, but can be good to be aware of. + +.. _performance-mode: + +Performance mode +================ + +This driver implements the +Documentation/userspace-api/sysfs-platform_profile.rst interface for working +with the "performance mode" function of the Samsung ACPI device. + +Mapping of each Samsung "performance mode" to its respective platform profile is +performed dynamically by the driver, as not all models support all of the same +performance modes. Your device might have one or more of the following mappings: + +- "Silent" maps to ``low-power`` +- "Quiet" maps to ``quiet`` +- "Optimized" maps to ``balanced`` +- "High performance" maps to ``performance`` + +The result of the mapping can be printed in the kernel log when the module is +loaded. Supported profiles can also be retrieved from +``/sys/firmware/acpi/platform_profile_choices``, while +``/sys/firmware/acpi/platform_profile`` can be used to read or write the +currently selected profile. + +The ``balanced`` platform profile will be set during module load if no profile +has been previously set. + +.. _battery-charge-control-end-threshold: + +Battery charge control end threshold +==================================== + +This platform driver will add the ability to set the battery's charge control +end threshold, but does not have the ability to set a start threshold. + +This feature is typically called "Battery Saver" by the various Samsung +applications in Windows, but in Linux we have implemented the standardized +"charge control threshold" sysfs interface on the battery device to allow for +controlling this functionality from the userspace. + +The sysfs attribute +``/sys/class/power_supply/BAT1/charge_control_end_threshold`` can be used to +read or set the desired charge end threshold. + +If you wish to maintain interoperability with the Samsung Settings application +in Windows, then you should set the value to 100 to represent "off", or enable +the feature using only one of the following values: 50, 60, 70, 80, or 90. +Otherwise, the driver will accept any value between 1 and 100 as the percentage +that you wish the battery to stop charging at. + +.. note:: + Some devices have been observed as automatically "turning off" the charge + control end threshold if an input value of less than 30 is given. + +.. _firmware-attributes: + +Firmware Attributes +=================== + +The following enumeration-typed firmware attributes are set up by this driver +and should be accessible under +``/sys/class/firmware-attributes/samsung-galaxybook/attributes/`` if your device +supports them: + +- ``power_on_lid_open`` (device should power on when the lid is opened) +- ``usb_charging`` (USB ports can deliver power to connected devices even when + the device is powered off or in a low sleep state) +- ``block_recording`` (blocks access to camera and microphone) + +All of these attributes are simple boolean-like enumeration values which use 0 +to represent "off" and 1 to represent "on". Use the ``current_value`` attribute +to get or change the setting on the device. + +Note that when ``block_recording`` is updated, the input device "Samsung Galaxy +Book Lens Cover" will receive a ``SW_CAMERA_LENS_COVER`` switch event which +reflects the current state. + +.. _keyboard-hotkey-actions: + +Keyboard hotkey actions (i8042 filter) +====================================== + +The i8042 filter will swallow the keyboard events for the Fn+F9 hotkey (Multi- +level keyboard backlight toggle) and Fn+F10 hotkey (Block recording toggle) +and instead execute their actions within the driver itself. + +Fn+F9 will cycle through the brightness levels of the keyboard backlight. A +notification will be sent using ``led_classdev_notify_brightness_hw_changed`` +so that the userspace can be aware of the change. This mimics the behavior of +other existing devices where the brightness level is cycled internally by the +embedded controller and then reported via a notification. + +Fn+F10 will toggle the value of the "block recording" setting, which blocks +or allows usage of the built-in camera and microphone (and generates the same +Lens Cover switch event mentioned above). + +.. _acpi-notifications-and-hotkey-actions: + +ACPI notifications and hotkey actions +===================================== + +ACPI notifications will generate ACPI netlink events under the device class +``samsung-galaxybook`` and bus ID matching the Samsung ACPI device ID found on +your device. The events can be received using userspace tools such as +``acpi_listen`` and ``acpid``. + +The Fn+F11 Performance mode hotkey will be handled by the driver; each keypress +will cycle to the next available platform profile. diff --git a/Documentation/admin-guide/media/cec.rst b/Documentation/admin-guide/media/cec.rst index 92690e1f2183..b2e7a300494a 100644 --- a/Documentation/admin-guide/media/cec.rst +++ b/Documentation/admin-guide/media/cec.rst @@ -451,7 +451,7 @@ configure the CEC devices for HDMI Input and the HDMI Outputs manually. --------------------- A three character manufacturer name that is used in the EDID for the HDMI -Input. If not set, then userspace is reponsible for configuring an EDID. +Input. If not set, then userspace is responsible for configuring an EDID. If set, then the driver will update the EDID automatically based on the resolutions supported by the connected displays, and it will not be possible anymore to manually set the EDID for the HDMI Input. diff --git a/Documentation/admin-guide/media/mgb4.rst b/Documentation/admin-guide/media/mgb4.rst index b9da127c074d..f69d331e3cb1 100644 --- a/Documentation/admin-guide/media/mgb4.rst +++ b/Documentation/admin-guide/media/mgb4.rst @@ -22,7 +22,9 @@ Global (PCI card) parameters | 0 - No module present | 1 - FPDL3 - | 2 - GMSL + | 2 - GMSL (one serializer, two daisy chained deserializers) + | 3 - GMSL (one serializer, two deserializers) + | 4 - GMSL (two deserializers with two daisy chain outputs) **module_version** (R): Module version number. Zero in case of a missing module. diff --git a/Documentation/admin-guide/pm/cpufreq.rst b/Documentation/admin-guide/pm/cpufreq.rst index a21369eba034..3950583f2b15 100644 --- a/Documentation/admin-guide/pm/cpufreq.rst +++ b/Documentation/admin-guide/pm/cpufreq.rst @@ -248,6 +248,20 @@ are the following: If that frequency cannot be determined, this attribute should not be present. +``cpuinfo_avg_freq`` + An average frequency (in KHz) of all CPUs belonging to a given policy, + derived from a hardware provided feedback and reported on a time frame + spanning at most few milliseconds. + + This is expected to be based on the frequency the hardware actually runs + at and, as such, might require specialised hardware support (such as AMU + extension on ARM). If one cannot be determined, this attribute should + not be present. + + Note, that failed attempt to retrieve current frequency for a given + CPU(s) will result in an appropriate error, i.e: EAGAIN for CPU that + remains idle (raised on ARM). + ``cpuinfo_max_freq`` Maximum possible operating frequency the CPUs belonging to this policy can run at (in kHz). @@ -293,7 +307,8 @@ are the following: Some architectures (e.g. ``x86``) may attempt to provide information more precisely reflecting the current CPU frequency through this attribute, but that still may not be the exact current CPU frequency as - seen by the hardware at the moment. + seen by the hardware at the moment. This behavior though, is only + available via c:macro:``CPUFREQ_ARCH_CUR_FREQ`` option. ``scaling_driver`` The scaling driver currently in use. diff --git a/Documentation/admin-guide/pm/cpuidle.rst b/Documentation/admin-guide/pm/cpuidle.rst index eb58d7a5affd..0c090b076224 100644 --- a/Documentation/admin-guide/pm/cpuidle.rst +++ b/Documentation/admin-guide/pm/cpuidle.rst @@ -275,20 +275,25 @@ values and, when predicting the idle duration next time, it computes the average and variance of them. If the variance is small (smaller than 400 square milliseconds) or it is small relative to the average (the average is greater that 6 times the standard deviation), the average is regarded as the "typical -interval" value. Otherwise, the longest of the saved observed idle duration +interval" value. Otherwise, either the longest or the shortest (depending on +which one is farther from the average) of the saved observed idle duration values is discarded and the computation is repeated for the remaining ones. + Again, if the variance of them is small (in the above sense), the average is taken as the "typical interval" value and so on, until either the "typical -interval" is determined or too many data points are disregarded, in which case -the "typical interval" is assumed to equal "infinity" (the maximum unsigned -integer value). - -If the "typical interval" computed this way is long enough, the governor obtains -the time until the closest timer event with the assumption that the scheduler -tick will be stopped. That time, referred to as the *sleep length* in what follows, -is the upper bound on the time before the next CPU wakeup. It is used to determine -the sleep length range, which in turn is needed to get the sleep length correction -factor. +interval" is determined or too many data points are disregarded. In the latter +case, if the size of the set of data points still under consideration is +sufficiently large, the next idle duration is not likely to be above the largest +idle duration value still in that set, so that value is taken as the predicted +next idle duration. Finally, if the set of data points still under +consideration is too small, no prediction is made. + +If the preliminary prediction of the next idle duration computed this way is +long enough, the governor obtains the time until the closest timer event with +the assumption that the scheduler tick will be stopped. That time, referred to +as the *sleep length* in what follows, is the upper bound on the time before the +next CPU wakeup. It is used to determine the sleep length range, which in turn +is needed to get the sleep length correction factor. The ``menu`` governor maintains an array containing several correction factor values that correspond to different sleep length ranges organized so that each @@ -302,7 +307,7 @@ to 1 the correction factor becomes (it must fall between 0 and 1 inclusive). The sleep length is multiplied by the correction factor for the range that it falls into to obtain an approximation of the predicted idle duration that is compared to the "typical interval" determined previously and the minimum of -the two is taken as the idle duration prediction. +the two is taken as the final idle duration prediction. If the "typical interval" value is small, which means that the CPU is likely to be woken up soon enough, the sleep length computation is skipped as it may diff --git a/Documentation/admin-guide/pm/intel_idle.rst b/Documentation/admin-guide/pm/intel_idle.rst index 39bd6ecce7de..5940528146eb 100644 --- a/Documentation/admin-guide/pm/intel_idle.rst +++ b/Documentation/admin-guide/pm/intel_idle.rst @@ -192,11 +192,19 @@ even if they have been enumerated (see :ref:`cpu-pm-qos` in Documentation/admin-guide/pm/cpuidle.rst). Setting ``max_cstate`` to 0 causes the ``intel_idle`` initialization to fail. -The ``no_acpi`` and ``use_acpi`` module parameters (recognized by ``intel_idle`` -if the kernel has been configured with ACPI support) can be set to make the -driver ignore the system's ACPI tables entirely or use them for all of the -recognized processor models, respectively (they both are unset by default and -``use_acpi`` has no effect if ``no_acpi`` is set). +The ``no_acpi``, ``use_acpi`` and ``no_native`` module parameters are +recognized by ``intel_idle`` if the kernel has been configured with ACPI +support. In the case that ACPI is not configured these flags have no impact +on functionality. + +``no_acpi`` - Do not use ACPI at all. Only native mode is available, no +ACPI mode. + +``use_acpi`` - No-op in ACPI mode, the driver will consult ACPI tables for +C-states on/off status in native mode. + +``no_native`` - Work only in ACPI mode, no native mode available (ignore +all custom tables). The value of the ``states_off`` module parameter (0 by default) represents a list of idle states to be disabled by default in the form of a bitmask. diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst index bf13ad25a32f..78fc83ed2a7e 100644 --- a/Documentation/admin-guide/pm/intel_pstate.rst +++ b/Documentation/admin-guide/pm/intel_pstate.rst @@ -696,6 +696,9 @@ of them have to be prepended with the ``intel_pstate=`` prefix. Use per-logical-CPU P-State limits (see `Coordination of P-state Limits`_ for details). +``no_cas`` + Do not enable capacity-aware scheduling (CAS) which is enabled by + default on hybrid systems. Diagnostics and Tuning ====================== diff --git a/Documentation/admin-guide/pnp.rst b/Documentation/admin-guide/pnp.rst index 3eda08191d13..24d80e3eb309 100644 --- a/Documentation/admin-guide/pnp.rst +++ b/Documentation/admin-guide/pnp.rst @@ -129,9 +129,6 @@ pnp_put_protocol pnp_register_protocol use this to register a new PnP protocol -pnp_unregister_protocol - use this function to remove a PnP protocol from the Plug and Play Layer - pnp_register_driver adds a PnP driver to the Plug and Play Layer diff --git a/Documentation/admin-guide/serial-console.rst b/Documentation/admin-guide/serial-console.rst index a3dfc2c66e01..1609e7479249 100644 --- a/Documentation/admin-guide/serial-console.rst +++ b/Documentation/admin-guide/serial-console.rst @@ -78,7 +78,9 @@ 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 first looks for a VGA card and then for a serial port. So if you don't have a VGA card in your system the first serial port will automatically -become the console. +become the console, unless the kernel is configured with the +CONFIG_NULL_TTY_DEFAULT_CONSOLE option, then it will default to using the +ttynull device. You will need to create a new device to use ``/dev/console``. The official ``/dev/console`` is now character device 5,1. diff --git a/Documentation/admin-guide/tainted-kernels.rst b/Documentation/admin-guide/tainted-kernels.rst index 700aa72eecb1..a0cc017e4424 100644 --- a/Documentation/admin-guide/tainted-kernels.rst +++ b/Documentation/admin-guide/tainted-kernels.rst @@ -101,6 +101,7 @@ Bit Log Number Reason that got the kernel tainted 16 _/X 65536 auxiliary taint, defined for and used by distros 17 _/T 131072 kernel was built with the struct randomization plugin 18 _/N 262144 an in-kernel test has been run + 19 _/J 524288 userspace used a mutating debug operation in fwctl === === ====== ======================================================== Note: The character ``_`` is representing a blank in this table to make reading @@ -184,3 +185,7 @@ More detailed explanation for tainting build time. 18) ``N`` if an in-kernel test, such as a KUnit test, has been run. + + 19) ``J`` if userpace opened /dev/fwctl/* and performed a FWTCL_RPC_DEBUG_WRITE + to use the devices debugging features. Device debugging features could + cause the device to malfunction in undefined ways. diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst index 2ed79f41a411..d0502691dfa1 100644 --- a/Documentation/admin-guide/thunderbolt.rst +++ b/Documentation/admin-guide/thunderbolt.rst @@ -28,7 +28,7 @@ should be a userspace tool that handles all the low-level details, keeps 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``. +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 diff --git a/Documentation/admin-guide/workload-tracing.rst b/Documentation/admin-guide/workload-tracing.rst index 6be38c1b9c5b..d6313890ee41 100644 --- a/Documentation/admin-guide/workload-tracing.rst +++ b/Documentation/admin-guide/workload-tracing.rst @@ -82,7 +82,7 @@ Install tools to build Linux kernel and tools in kernel repository. scripts/ver_linux is a good way to check if your system already has the necessary tools:: - sudo apt-get build-essentials flex bison yacc + sudo apt-get install build-essential flex bison yacc sudo apt install libelf-dev systemtap-sdt-dev libslang2-dev libperl-dev libdw-dev cscope is a good tool to browse kernel sources. Let's install it now:: |