Merge tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Linus Torvalds authored
Pull networking updates from Jakub Kicinski:
 "Core:

   - Introduce and use a single page frag cache for allocating small skb
     heads, clawing back the 10-20% performance regression in UDP flood
     test from previous fixes.

   - Run packets which already went thru HW coalescing thru SW GRO. This
     significantly improves TCP segment coalescing and simplifies
     deployments as different workloads benefit from HW or SW GRO.

   - Shrink the size of the base zero-copy send structure.

   - Move TCP init under a new slow / sleepable version of DO_ONCE().

  BPF:

   - Add BPF-specific, any-context-safe memory allocator.

   - Add helpers/kfuncs for PKCS#7 signature verification from BPF
     programs.

   - Define a new map type and related helpers for user space -> kernel
     communication over a ring buffer (BPF_MAP_TYPE_USER_RINGBUF).

   - Allow targeting BPF iterators to loop through resources of one
     task/thread.

   - Add ability to call selected destructive functions. Expose
     crash_kexec() to allow BPF to trigger a kernel dump. Use
     CAP_SYS_BOOT check on the loading process to judge permissions.

   - Enable BPF to collect custom hierarchical cgroup stats efficiently
     by integrating with the rstat framework.

   - Support struct arguments for trampoline based programs. Only
     structs with size <= 16B and x86 are supported.

   - Invoke cgroup/connect{4,6} programs for unprivileged ICMP ping
     sockets (instead of just TCP and UDP sockets).

   - Add a helper for accessing CLOCK_TAI for time sensitive network
     related programs.

   - Support accessing network tunnel metadata's flags.

   - Make TCP SYN ACK RTO tunable by BPF programs with TCP Fast Open.

   - Add support for writing to Netfilter's nf_conn:mark.

  Protocols:

   - WiFi: more Extremely High Throughput (EHT) and Multi-Link Operation
     (MLO) work (802.11be, WiFi 7).

   - vsock: improve support for SO_RCVLOWAT.

   - SMC: support SO_REUSEPORT.

   - Netlink: define and document how to use netlink in a "modern" way.
     Support reporting missing attributes via extended ACK.

   - IPSec: support collect metadata mode for xfrm interfaces.

   - TCPv6: send consistent autoflowlabel in SYN_RECV state and RST
     packets.

   - TCP: introduce optional per-netns connection hash table to allow
     better isolation between namespaces (opt-in, at the cost of memory
     and cache pressure).

   - MPTCP: support TCP_FASTOPEN_CONNECT.

   - Add NEXT-C-SID support in Segment Routing (SRv6) End behavior.

   - Adjust IP_UNICAST_IF sockopt behavior for connected UDP sockets.

   - Open vSwitch:
      - Allow specifying ifindex of new interfaces.
      - Allow conntrack and metering in non-initial user namespace.

   - TLS: support the Korean ARIA-GCM crypto algorithm.

   - Remove DECnet support.

  Driver API:

   - Allow selecting the conduit interface used by each port in DSA
     switches, at runtime.

   - Ethernet Power Sourcing Equipment and Power Device support.

   - Add tc-taprio support for queueMaxSDU parameter, i.e. setting per
     traffic class max frame size for time-based packet schedules.

   - Support PHY rate matching - adapting between differing host-side
     and link-side speeds.

   - Introduce QUSGMII PHY mode and 1000BASE-KX interface mode.

   - Validate OF (device tree) nodes for DSA shared ports; make
     phylink-related properties mandatory on DSA and CPU ports.
     Enforcing more uniformity should allow transitioning to phylink.

   - Require that flash component name used during update matches one of
     the components for which version is reported by info_get().

   - Remove "weight" argument from driver-facing NAPI API as much as
     possible. It's one of those magic knobs which seemed like a good
     idea at the time but is too indirect to use in practice.

   - Support offload of TLS connections with 256 bit keys.

  New hardware / drivers:

   - Ethernet:
      - Microchip KSZ9896 6-port Gigabit Ethernet Switch
      - Renesas Ethernet AVB (EtherAVB-IF) Gen4 SoCs
      - Analog Devices ADIN1110 and ADIN2111 industrial single pair
        Ethernet (10BASE-T1L) MAC+PHY.
      - Rockchip RV1126 Gigabit Ethernet (a version of stmmac IP).

   - Ethernet SFPs / modules:
      - RollBall / Hilink / Turris 10G copper SFPs
      - HALNy GPON module

   - WiFi:
      - CYW43439 SDIO chipset (brcmfmac)
      - CYW89459 PCIe chipset (brcmfmac)
      - BCM4378 on Apple platforms (brcmfmac)

  Drivers:

   - CAN:
      - gs_usb: HW timestamp support

   - Ethernet PHYs:
      - lan8814: cable diagnostics

   - Ethernet NICs:
      - Intel (100G):
         - implement control of FCS/CRC stripping
         - port splitting via devlink
         - L2TPv3 filtering offload
      - nVidia/Mellanox:
         - tunnel offload for sub-functions
         - MACSec offload, w/ Extended packet number and replay window
           offload
         - significantly restructure, and optimize the AF_XDP support,
           align the behavior with other vendors
      - Huawei:
         - configuring DSCP map for traffic class selection
         - querying standard FEC statistics
         - querying SerDes lane number via ethtool
      - Marvell/Cavium:
         - egress priority flow control
         - MACSec offload
      - AMD/SolarFlare:
         - PTP over IPv6 and raw Ethernet
      - small / embedded:
         - ax88772: convert to phylink (to support SFP cages)
         - altera: tse: convert to phylink
         - ftgmac100: support fixed link
         - enetc: standard Ethtool counters
         - macb: ZynqMP SGMII dynamic configuration support
         - tsnep: support multi-queue and use page pool
         - lan743x: Rx IP & TCP checksum offload
         - igc: add xdp frags support to ndo_xdp_xmit

   - Ethernet high-speed switches:
      - Marvell (prestera):
         - support SPAN port features (traffic mirroring)
         - nexthop object offloading
      - Microchip (sparx5):
         - multicast forwarding offload
         - QoS queuing offload (tc-mqprio, tc-tbf, tc-ets)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - support RGMII cmode
      - NXP (felix):
         - standardized ethtool counters
      - Microchip (lan966x):
         - QoS queuing offload (tc-mqprio, tc-tbf, tc-cbs, tc-ets)
         - traffic policing and mirroring
         - link aggregation / bonding offload
         - QUSGMII PHY mode support

   - Qualcomm 802.11ax WiFi (ath11k):
      - cold boot calibration support on WCN6750
      - support to connect to a non-transmit MBSSID AP profile
      - enable remain-on-channel support on WCN6750
      - Wake-on-WLAN support for WCN6750
      - support to provide transmit power from firmware via nl80211
      - support to get power save duration for each client
      - spectral scan support for 160 MHz

   - MediaTek WiFi (mt76):
      - WiFi-to-Ethernet bridging offload for MT7986 chips

   - RealTek WiFi (rtw89):
      - P2P support"

* tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1864 commits)
  eth: pse: add missing static inlines
  once: rename _SLOW to _SLEEPABLE
  net: pse-pd: add regulator based PSE driver
  dt-bindings: net: pse-dt: add bindings for regulator based PoDL PSE controller
  ethtool: add interface to interact with Ethernet Power Equipment
  net: mdiobus: search for PSE nodes by parsing PHY nodes.
  net: mdiobus: fwnode_mdiobus_register_phy() rework error handling
  net: add framework to support Ethernet PSE and PDs devices
  dt-bindings: net: phy: add PoDL PSE property
  net: marvell: prestera: Propagate nh state from hw to kernel
  net: marvell: prestera: Add neighbour cache accounting
  net: marvell: prestera: add stub handler neighbour events
  net: marvell: prestera: Add heplers to interact with fib_notifier_info
  net: marvell: prestera: Add length macros for prestera_ip_addr
  net: marvell: prestera: add delayed wq and flush wq on deinit
  net: marvell: prestera: Add strict cleanup of fib arbiter
  net: marvell: prestera: Add cleanup of allocated fib_nodes
  net: marvell: prestera: Add router nexthops ABI
  eth: octeon: fix build after netif_napi_add() changes
  net/mlx5: E-Switch, Return EBUSY if can't get mode lock
  ...
0326074f
Name Last commit Last update
..
LSM security/loadpin: Update the changing interface in the source code.
acpi ACPI: docs: Drop useless DSDT override documentation
aoe docs: aoe: add it to the driver-api book
auxdisplay treewide: Miguel has moved
blockdev Merge tag 'docs-5.19-2' of git://git.lwn.net/linux
cgroup-v1 filemap: Remove add_to_page_cache() and add_to_page_cache_locked()
cifs Documentation, arch: Remove leftovers from CIFS_WEAK_PW_HASH
device-mapper dm writecache: count number of blocks discarded, not number of discard bios
gpio gpio: sim: add doc file to index file
hw-vuln Merge tag 'docs-6.1' of git://git.lwn.net/linux
kdump Remove duplicate words inside documentation
laptops lg-laptop: Move setting of battery charge limit to common location
media media: vimc: documentation for lens
mm Merge tag 'docs-6.1' of git://git.lwn.net/linux
namespaces docs: add SPDX tags to new index files
nfs NFS: update documentation for the nfs4_unique_id parameter
perf docs: perf: Include hns3-pmu.rst in toctree to fix 'htmldocs' WARNING
pm Merge tag 'x86_cpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
sysctl bpf: Use bpf_capable() instead of CAP_SYS_ADMIN for blinding decision
README.rst Merge tag 'docs-6.1' of git://git.lwn.net/linux
abi-obsolete.rst docs: ABI: don't escape ReST-incompatible chars from obsolete and removed
abi-removed.rst docs: ABI: don't escape ReST-incompatible chars from obsolete and removed
abi-stable.rst docs: ABI: make it parse ABI/stable as ReST-compatible files
abi-testing.rst docs: abi-testing.rst: enable --rst-sources when building docs
abi.rst docs: ABI: create a 2-depth index for ABI
bcache.rst
binderfs.rst
binfmt-misc.rst
bootconfig.rst
braille-console.rst
btmrvl.rst
bug-bisect.rst
bug-hunting.rst
cgroup-v2.rst
clearing-warn-once.rst
cpu-load.rst
cputopology.rst
dell_rbu.rst
devices.rst
devices.txt
dynamic-debug-howto.rst
edid.rst
efi-stub.rst
ext4.rst
features.rst
filesystem-monitoring.rst
highuid.rst
hw_random.rst
index.rst
init.rst
initrd.rst
iostats.rst
java.rst
jfs.rst
kernel-parameters.rst
kernel-parameters.txt
kernel-per-CPU-kthreads.rst
lcd-panel-cgram.rst
ldm.rst
lockup-watchdogs.rst
md.rst
module-signing.rst
mono.rst
numastat.rst
parport.rst
perf-security.rst
pnp.rst
pstore-blk.rst
ramoops.rst
rapidio.rst
ras.rst
reporting-issues.rst
reporting-regressions.rst
rtc.rst
security-bugs.rst
serial-console.rst
spkguide.txt
svga.rst
syscall-user-dispatch.rst
sysfs-rules.rst
sysrq.rst
tainted-kernels.rst
thunderbolt.rst
ufs.rst
unicode.rst
vga-softcursor.rst
video-output.rst
xfs.rst

.. _readme:

Linux kernel release 6.x
=============================================

These are the release notes for Linux version 6. Read them carefully,
as they tell you what this is all about, explain how to install the
kernel, and what to do if something goes wrong.

What is Linux?
--------------

Linux is a clone of the operating system Unix, written from scratch by
Linus Torvalds with assistance from a loosely-knit team of hackers across
the Net. It aims towards POSIX and Single UNIX Specification compliance.

It has all the features you would expect in a modern fully-fledged Unix,
including true multitasking, virtual memory, shared libraries, demand
loading, shared copy-on-write executables, proper memory management,
and multistack networking including IPv4 and IPv6.

It is distributed under the GNU General Public License v2 - see the
accompanying COPYING file for more details.

On what hardware does it run?
-----------------------------

Although originally developed first for 32-bit x86-based PCs (386 or higher),
today Linux also runs on (at least) the Compaq Alpha AXP, Sun SPARC and
UltraSPARC, Motorola 68000, PowerPC, PowerPC64, ARM, Hitachi SuperH, Cell,
IBM S/390, MIPS, HP PA-RISC, Intel IA-64, DEC VAX, AMD x86-64 Xtensa, and
ARC architectures.

Linux is easily portable to most general-purpose 32- or 64-bit architectures
as long as they have a paged memory management unit (PMMU) and a port of the
GNU C compiler (gcc) (part of The GNU Compiler Collection, GCC). Linux has
also been ported to a number of architectures without a PMMU, although
functionality is then obviously somewhat limited.
Linux has also been ported to itself. You can now run the kernel as a
userspace application - this is called UserMode Linux (UML).

Documentation
-------------

- There is a lot of documentation available both in electronic form on
the Internet and in books, both Linux-specific and pertaining to
general UNIX questions. I'd recommend looking into the documentation
subdirectories on any Linux FTP site for the LDP (Linux Documentation
Project) books. This README is not meant to be documentation on the
system: there are much better sources available.

- There are various README files in the Documentation/ subdirectory:
these typically contain kernel-specific installation notes for some
drivers for example. Please read the
:ref:`Documentation/process/changes.rst ` file, as it
contains information about the problems, which may result by upgrading
your kernel.

Installing the kernel source
----------------------------

- If you install the full sources, put the kernel tarball in a
directory where you have permissions (e.g. your home directory) and
unpack it::

xz -cd linux-6.x.tar.xz | tar xvf -

Replace "X" with the version number of the latest kernel.

Do NOT use the /usr/src/linux area! This area has a (usually
incomplete) set of kernel headers that are used by the library header
files. They should match the library, and not get messed up by
whatever the kernel-du-jour happens to be.

- You can also upgrade between 6.x releases by patching. Patches are
distributed in the xz format. To install by patching, get all the
newer patch files, enter the top level directory of the kernel source
(linux-6.x) and execute::

xz -cd ../patch-6.x.xz | patch -p1

Replace "x" for all versions bigger than the version "x" of your current
source tree, **in_order**, and you should be ok. You may want to remove
the backup files (some-file-name~ or some-file-name.orig), and make sure
that there are no failed patches (some-file-name# or some-file-name.rej).
If there are, either you or I have made a mistake.

Unlike patches for the 6.x kernels, patches for the 6.x.y kernels
(also known as the -stable kernels) are not incremental but instead apply
directly to the base 6.x kernel. For example, if your base kernel is 6.0
and you want to apply the 6.0.3 patch, you must not first apply the 6.0.1
and 6.0.2 patches. Similarly, if you are running kernel version 6.0.2 and
want to jump to 6.0.3, you must first reverse the 6.0.2 patch (that is,
patch -R) **before** applying the 6.0.3 patch. You can read more on this in
:ref:`Documentation/process/applying-patches.rst `.

Alternatively, the script patch-kernel can be used to automate this
process. It determines the current kernel version and applies any
patches found::

linux/scripts/patch-kernel linux

The first argument in the command above is the location of the
kernel source. Patches are applied from the current directory, but
an alternative directory can be specified as the second argument.

- Make sure you have no stale .o files and dependencies lying around::

cd linux
make mrproper

You should now have the sources correctly installed.

Software requirements
---------------------

Compiling and running the 6.x kernels requires up-to-date
versions of various software packages. Consult
:ref:`Documentation/process/changes.rst ` for the minimum version numbers
required and how to get updates for these packages. Beware that using
excessively old versions of these packages can cause indirect
errors that are very difficult to track down, so don't assume that
you can just update packages when obvious problems arise during
build or operation.

Build directory for the kernel
------------------------------

When compiling the kernel, all output files will per default be
stored together with the kernel source code.
Using the option ``make O=output/dir`` allows you to specify an alternate
place for the output files (including .config).
Example::

kernel source code: /usr/src/linux-6.x
build directory: /home/name/build/kernel

To configure and build the kernel, use::

cd /usr/src/linux-6.x
make O=/home/name/build/kernel menuconfig
make O=/home/name/build/kernel
sudo make O=/home/name/build/kernel modules_install install

Please note: If the ``O=output/dir`` option is used, then it must be
used for all invocations of make.

Configuring the kernel
----------------------

Do not skip this step even if you are only upgrading one minor
version. New configuration options are added in each release, and
odd problems will turn up if the configuration files are not set up
as expected. If you want to carry your existing configuration to a
new version with minimal work, use ``make oldconfig``, which will
only ask you for the answers to new questions.

- Alternative configuration commands are::

"make config" Plain text interface.

"make menuconfig" Text based color menus, radiolists & dialogs.

"make nconfig" Enhanced text based color menus.

"make xconfig" Qt 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
new config symbols.

"make olddefconfig"
Like above, but sets new symbols to their default
values without prompting.

"make defconfig" Create a ./.config file by using the default
symbol values from either arch/$ARCH/defconfig
or arch/$ARCH/configs/${PLATFORM}_defconfig,
depending on the architecture.

"make ${PLATFORM}_defconfig"
Create a ./.config file by using the default
symbol values from
arch/$ARCH/configs/${PLATFORM}_defconfig.
Use "make help" to get a list of all available
platforms of your architecture.

"make allyesconfig"
Create a ./.config file by setting symbol
values to 'y' as much as possible.

"make allmodconfig"
Create a ./.config file by setting symbol
values to 'm' as much as possible.

"make allnoconfig" Create a ./.config file by setting symbol
values to 'n' as much as possible.

"make randconfig" Create a ./.config file by setting symbol
values to random values.

"make localmodconfig" Create a config based on current config and
loaded modules (lsmod). Disables any module
option that is not needed for the loaded modules.

To create a localmodconfig for another machine,
store the lsmod of that machine into a file
and pass it in as a LSMOD parameter.

Also, you can preserve modules in certain folders
or kconfig files by specifying their paths in
parameter LMC_KEEP.

target$ lsmod > /tmp/mylsmod
target$ scp /tmp/mylsmod host:/tmp

host$ make LSMOD=/tmp/mylsmod \
LMC_KEEP="drivers/usb:drivers/gpu:fs" \
localmodconfig

The above also works when cross compiling.

"make localyesconfig" Similar to localmodconfig, except it will convert
all module options to built in (=y) options. You can
also preserve modules by LMC_KEEP.

"make kvm_guest.config" Enable additional options for kvm guest kernel
support.

"make xen.config" Enable additional options for xen dom0 guest kernel
support.

"make tinyconfig" Configure the tiniest possible kernel.

You can find more information on using the Linux kernel config tools
in Documentation/kbuild/kconfig.rst.

- NOTES on ``make config``:

- Having unnecessary drivers will make the kernel bigger, and can
under some circumstances lead to problems: probing for a
nonexistent controller card may confuse your other controllers.

- A kernel with math-emulation compiled in will still use the
coprocessor if one is present: the math emulation will just
never get used in that case. The kernel will be slightly larger,
but will work on different machines regardless of whether they
have a math coprocessor or not.

- The "kernel hacking" configuration details usually result in a
bigger or slower kernel (or both), and can even make the kernel
less stable by configuring some routines to actively try to
break bad code to find kernel problems (kmalloc()). Thus you
should probably answer 'n' to the questions for "development",
"experimental", or "debugging" features.

Compiling the kernel
--------------------

- Make sure you have at least gcc 5.1 available.
For more information, refer to :ref:`Documentation/process/changes.rst `.

- Do a ``make`` to create a compressed kernel image. It is also
possible to do ``make install`` if you have lilo installed to suit the
kernel makefiles, but you may want to check your particular lilo setup first.

To do the actual install, you have to be root, but none of the normal
build should require that. Don't take the name of root in vain.

- If you configured any of the parts of the kernel as ``modules``, you
will also have to do ``make modules_install``.

- Verbose kernel compile/build output:

Normally, the kernel build system runs in a fairly quiet mode (but not
totally silent). However, sometimes you or other kernel developers need
to see compile, link, or other commands exactly as they are executed.
For this, use "verbose" build mode. This is done by passing
``V=1`` to the ``make`` command, e.g.::

make V=1 all

To have the build system also tell the reason for the rebuild of each
target, use ``V=2``. The default is ``V=0``.

- Keep a backup kernel handy in case something goes wrong. This is
especially true for the development releases, since each new release
contains new code which has not been debugged. Make sure you keep a
backup of the modules corresponding to that kernel, as well. If you
are installing a new kernel with the same version number as your
working kernel, make a backup of your modules directory before you
do a ``make modules_install``.

Alternatively, before compiling, use the kernel config option
"LOCALVERSION" to append a unique suffix to the regular kernel version.
LOCALVERSION can be set in the "General Setup" menu.

- In order to boot your new kernel, you'll need to copy the kernel
image (e.g. .../linux/arch/x86/boot/bzImage after compilation)
to the place where your regular bootable kernel is found.

- Booting a kernel directly from a floppy without the assistance of a
bootloader such as LILO, is no longer supported.

If you boot Linux from the hard drive, chances are you use LILO, which
uses the kernel image as specified in the file /etc/lilo.conf. The
kernel image file is usually /vmlinuz, /boot/vmlinuz, /bzImage or
/boot/bzImage. To use the new kernel, save a copy of the old image
and copy the new image over the old one. Then, you MUST RERUN LILO
to update the loading map! If you don't, you won't be able to boot
the new kernel image.

Reinstalling LILO is usually a matter of running /sbin/lilo.
You may wish to edit /etc/lilo.conf to specify an entry for your
old kernel image (say, /vmlinux.old) in case the new one does not
work. See the LILO docs for more information.

After reinstalling LILO, you should be all set. Shutdown the system,
reboot, and enjoy!

If you ever need to change the default root device, video mode,
etc. in the kernel image, use your bootloader's boot options
where appropriate. No need to recompile the kernel to change
these parameters.

- Reboot with the new kernel and enjoy.

If something goes wrong
-----------------------

If you have problems that seem to be due to kernel bugs, please follow the
instructions at 'Documentation/admin-guide/reporting-issues.rst'.

Hints on understanding kernel bug reports are in
'Documentation/admin-guide/bug-hunting.rst'. More on debugging the kernel
with gdb is in 'Documentation/dev-tools/gdb-kernel-debugging.rst' and
'Documentation/dev-tools/kgdb.rst'.