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Larysa Zaremba 5e7695e021 idpf: Interpret .set_channels() input differently
Unlike ice, idpf does not check, if user has requested at least 1 combined
channel. Instead, it relies on a check in the core code. Unfortunately, the
check does not trigger for us because of the hacky .set_channels()
interpretation logic that is not consistent with the core code.

This naturally leads to user being able to trigger a crash with an invalid
input. This is how:

1. ethtool -l <IFNAME> -> combined: 40
2. ethtool -L <IFNAME> rx 0 tx 0
   combined number is not specified, so command becomes {rx_count = 0,
   tx_count = 0, combined_count = 40}.
3. ethnl_set_channels checks, if there is at least 1 RX and 1 TX channel,
   comparing (combined_count + rx_count) and (combined_count + tx_count)
   to zero. Obviously, (40 + 0) is greater than zero, so the core code
   deems the input OK.
4. idpf interprets `rx 0 tx 0` as 0 channels and tries to proceed with such
   configuration.

The issue has to be solved fundamentally, as current logic is also known to
cause AF_XDP problems in ice [0].

Interpret the command in a way that is more consistent with ethtool
manual [1] (--show-channels and --set-channels) and new ice logic.

Considering that in the idpf driver only the difference between RX and TX
queues forms dedicated channels, change the correct way to set number of
channels to:

ethtool -L <IFNAME> combined 10 /* For symmetric queues */
ethtool -L <IFNAME> combined 8 tx 2 rx 0 /* For asymmetric queues */

[0] https://lore.kernel.org/netdev/20240418095857.2827-1-larysa.zaremba@intel.com/
[1] https://man7.org/linux/man-pages/man8/ethtool.8.html

Fixes: 02cbfba1ad ("idpf: add ethtool callbacks")
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Igor Bagnucki <igor.bagnucki@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-23 13:02:26 +02:00
arch Probes updates for v6.10: 2024-05-17 18:29:30 -07:00
block SCSI misc on 20240514 2024-05-14 18:25:53 -07:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto Hi, 2024-05-15 09:22:34 -07:00
Documentation Including fix from Andrii for the issue mentioned in our net-next PR, 2024-05-17 18:57:14 -07:00
drivers idpf: Interpret .set_channels() input differently 2024-05-23 13:02:26 +02:00
fs tracing cleanups for v6.10: 2024-05-17 18:34:27 -07:00
include tracing ring buffer updates for v6.10: 2024-05-17 18:40:37 -07:00
init Bootconfig updates for v6.10: 2024-05-17 18:23:55 -07:00
io_uring for-6.10/io_uring-20240511 2024-05-13 12:48:06 -07:00
ipc sysctl changes for v6.10-rc1 2024-05-17 17:31:24 -07:00
kernel kprobe/ftrace: fix build error due to bad function definition 2024-05-17 19:17:55 -07:00
lib Probes updates for v6.10: 2024-05-17 18:29:30 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm ARM: 2024-05-15 14:46:43 -07:00
net nfc: nci: Fix handling of zero-length payload packets in nci_rx_work() 2024-05-23 12:39:44 +02:00
rust Timers and timekeeping updates: 2024-05-14 09:27:40 -07:00
samples Networking changes for 6.10. 2024-05-14 19:42:24 -07:00
scripts Modules changes for v6.10-rc1 2024-05-15 14:05:08 -07:00
security integrity-v6.10 2024-05-15 08:43:02 -07:00
sound ALSA: hda/realtek: Drop doubly quirk entry for 103c:8a2e 2024-05-13 12:54:46 +02:00
tools testing: net-drv: use stats64 for testing 2024-05-23 10:18:29 +02:00
usr Kbuild updates for v6.8 2024-01-18 17:57:07 -08:00
virt KVM x86 misc changes for 6.10: 2024-05-12 03:18:44 -04:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig
.editorconfig Add .editorconfig file for basic formatting 2023-12-28 16:22:47 +09:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: create a list of all built DTB files 2024-02-19 18:20:39 +09:00
.mailmap Another not-too-busy cycle for documentation, including: 2024-05-13 10:51:53 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Drop Gustavo Pimentel as PCI DWC Maintainer 2024-03-27 13:41:02 -05:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Including fix from Andrii for the issue mentioned in our net-next PR, 2024-05-17 18:57:14 -07:00
Makefile Linux 6.9 2024-05-12 14:12:29 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.