cleanup: increase base kernel support

CONTRIBUTING.md

@@ -5,7 +5,7 @@ follow the contributing guidelines to make review of changes easier.
 
 ## Submitting changes
 
-1. Fork Onload repository on https://github.com/Xilinx/onload
+1. Fork Onload repository on https://github.com/Xilinx-CNS/onload
 2. Make local short-lived branch off of public master.
 3. Develop on branch locally. Please describe the changes you have made in
 the commit messages.
@@ -37,6 +37,16 @@ if( ! conditional_expr ) {
 }
 ```
 
+## Compatibility
+
+If your change is at high risk of introducing compatibilty issues, likely
+in relation to interfaces provided by the kernel, please perform a build
+test with one of the older supported kernels or operating systems. The
+following files help with defining compatibility definitions:
+
+* `scripts/libc_compat.sh`
+* `src/include/ci/driver/kernel_compat.h`
+
 ## Copyright
 
-This file: (c) Copyright 2020 Xilinx, Inc.
+This file: (c) Copyright 2020, 2024 Advanced Micro Devices, Inc.

README.md

@@ -22,43 +22,74 @@ protocol when the application is not scheduled.
 OpenOnload is distributed as source code. Instructions for building, packaging
 and installing may be found in [DEVELOPING.md](DEVELOPING.md)
 
-For each interface on which Onload is to use AF_XDP, execute the following:
+If there are any interfaces to be accelerated by Onload which are not
+AMD Solarflare interfaces, execute the following to register those interfaces
+to be accelerated using AF_XDP:
 
 ```sh
 echo ens2f0 > /sys/module/sfc_resource/afxdp/register
 ```
 
-Nota bene: for linux<5.11 you may need to run `ulimit -l unlimited`
-before the line above.
-
 The application to be Onloaded should be launched by prefixing the command
 line with `onload`.
 
-## Contributors
+## Support
 
-Please see [CONTRIBUTING.md](CONTRIBUTING.md)
+The publicly-hosted repository is a community-supported project. When raising
+issues on this repository it is expected that users will be running
+from the head of the git tree to pick up recent changes, not using official
+versions of Onload that were typically released before recent breaking kernel
+changes appeared as that is likely to lead to many duplicate issues being
+raised. Incompatibilities introduced by recent kernel versions are likely
+to be fixed rapidly here in this repository.
 
-## Onload with AF_XDP
+Supported releases of OpenOnload are available from
+<https://www.xilinx.com/support/download/nic-software-and-drivers.html#open>.
+Please raise issues on _supported releases_ of Onload with
+<[email protected]>.
 
-### Compatible network adapters, drivers and operating systems
+## Compatible Linux kernels and distributions
+
+This source tree is compatible with the following Linux kernels and
+distributions:
+
+* Debian 12
+* Ubuntu LTS 22.04, 24.04
+* Red Hat Enterprise Linux 8.6 - 8.10
+* Red Hat Enterprise Linux 9.0 - 9.4
+* kernel.org Linux kernels 5.11 - 6.9
 
-OpenOnload can accelerate applications on operating systems with AF_XDP support.
-AF_XDP support needs Linux kernel version 5.3 or later. To support zero-copy,
-Onload needs AF_XDP network adapter drivers to implement the necessary AF_XDP
-primitives. Typically the latest drivers from the network adapter vendors will
-support these primitives.
+## Onload with AMD Solarflare NICs
 
-The AF_XDP support is currently under development and is not yet at final
-release quality.
+Onload provides optimum networking acceleration and additional features using
+the native ef_vi hardware interface provided by AMD Solarflare network
+adapters compared to using Linux's AF_XDP mechanism. In this mode kernel and
+driver support for AF_XDP is not required.
 
-The following operating system distributions are the minimum versions known
-to provide an adequate level of AF_XDP support for Onload:
+A version of the 'sfc' net driver for AMD Solarflare network adapters is
+included.
 
-* Ubuntu LTS 20.04
-* Debian 10 with Linux kernel 5.10
-* Redhat Enterprise Linux 8.3
-* Redhat Enterprise Linux 9.0
-* kernel.org Linux kernels from version 5.4
+### Compatible AMD Solarflare network adapters
+
+The following adapters are able to support OpenOnload without AF_XDP:
+
+* SFN8522, SFN8542, SFN8042
+* X2522, X2522-25G, X2541
+* X3522
+
+## Onload with AF_XDP
+
+OpenOnload can accelerate applications on non-Solarflare network adapters
+with support for AF_XDP.
+
+### Compatible network adapters, drivers and operating systems
+
+To support zero-copy, Onload needs AF_XDP network adapter drivers to implement
+the necessary AF_XDP primitives. Typically the latest drivers from the network
+adapter vendors will support these primitives.
+
+The AF_XDP support is a community-supported work in progress that is not
+currently at release quality.
 
 If a netdriver does not support AF_XDP in native mode, Onload will try to use
 generic XDP mode when registering an interface. To make it work, one has to set
@@ -68,7 +99,7 @@ $ make -C ./src/tools/bpf_link_helper/
 $ echo $(realpath ./src/tools/bpf_link_helper/bpf-link-helper) | sudo tee /sys/module/sfc_resource/parameters/bpf_link_helper
 ```
 
-### Building without Xilinx NICs, for AF_XDP only
+### Building without AMD Solarflare NICs, for AF_XDP only
 
 OpenOnload can be built without SFC driver:
 * `make`: use `HAVE_SFC=0` variable;
@@ -79,42 +110,10 @@ Also, it can be built without EFCT and AUX support:
 * `make`: use `HAVE_EFCT=0` variable;
 * `onload_build`: use `--no-efct` parameter.
 
-## Native Onload with Xilinx/AMD NICs
-
-Onload also works with the native ef_vi hardware interface, supported by Xilinx
-network adapters. In this mode of operation, AF_XDP kernel and driver support
-is not required. This allows Onload to be used on older operating systems and
-take advantage of additional features. A version of the 'sfc' net driver for
-Xilinx network adapters is included.
-
-### Compatible Xilinx network adapters
-
-The following adapters at least are able to support OpenOnload without AF_XDP:
-
-* X2541
-* X2522, X2522-25G
-* X3522
-* SFN8042
-* SFN8522, SFN8542
-
-### Compatible Linux kernels and distributions for AMD Solarflare network adapters
+## Contributions
 
-This source tree is known to work with AMD Solarflare network adapters
-on the following Linux distributions:
-
-* Ubuntu LTS 20.04, LTS 22.04
-* Debian 11, 12
-* Redhat Enterprise Linux 8.1 - 8.9
-* Redhat Enterprise Linux 9.0 - 9.3
-* Linux kernel in the range 4.15 - 6.6
-
-## Support
-
-The publicly-hosted repository is a community-supported project.
-
-Supported releases of OpenOnload are available from
-https://www.xilinx.com/support/download/nic-software-and-drivers.html#open
+Please see [CONTRIBUTING.md](CONTRIBUTING.md)
 
 ## Copyright
 
-This file: (c) Copyright 2020-2024 Xilinx, Inc.
+This file: (c) Copyright 2020-2024 Advanced Micro Devices, Inc.