No description
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Douglas Anderson 43cd3ddbff dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW
When trying to turn on the "pseudo NMI" kernel feature in Linux, it
was discovered that all Mediatek-based Chromebooks that ever shipped
(at least ones with GICv3) had a firmware bug where they wouldn't save
certain GIC "GICR" registers properly. If a processor ever entered a
suspend/idle mode where the GICR registers lost state then they'd be
reset to their default state.

As a result of the bug, if you try to enable "pseudo NMIs" on the
affected devices then certain interrupts will unexpectedly get
promoted to be "pseudo NMIs" and cause crashes / freezes / general
mayhem.

ChromeOS is looking to start turning on "pseudo NMIs" in production to
make crash reports more actionable. To do so, we will release firmware
updates for at least some of the affected Mediatek Chromebooks.
However, even when we update the firmware of a Chromebook it's always
possible that a user will end up booting with old firmware. We need to
be able to detect when we're running with firmware that will crash and
burn if pseudo NMIs are enabled.

The current plan is:
* Update the device trees of all affected Chromebooks to include the
  'mediatek,broken-save-restore-fw' property. The kernel can use this
  to know not to enable certain features like "pseudo NMI". NOTE:
  device trees for Chromebooks are never baked into the firmware but
  are bundled with the kernel. A kernel will never be configured to
  use "pseudo NMIs" and be bundled with an old device tree.
* When we get a fixed firmware for one of these Chromebooks, it will
  patch the device tree to remove this property.

For some details, you can also see the public bug
<https://issuetracker.google.com/281831288>

Reviewed-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230515131353.v2.1.Iabe67a827e206496efec6beb5616d5a3b99c1e65@changeid
History 2023-05-16 10:42:57 +01:00
arch s390: remove the unneeded select GCC12_NO_ARRAY_BOUNDS 2023-05-05 18:56:23 -07:00
block for-6.4/block-2023-05-06 2023-05-06 08:28:58 -07:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto This push fixes the following problems: 2023-05-07 10:57:14 -07:00
Documentation dt-bindings: interrupt-controller: arm,gic-v3: Add quirk for Mediatek SoCs w/ broken FW 2023-05-16 10:42:57 +01:00
drivers This push fixes the following problems: 2023-05-07 10:57:14 -07:00
fs 9 smb3 client fixes, mostly DFS or reconnect related 2023-05-07 10:46:21 -07:00
include - mailbox api: allow direct registration to a channel 2023-05-07 10:17:33 -07:00
init Objtool changes for v6.4: 2023-04-28 14:02:54 -07:00
io_uring for-6.4/io_uring-2023-05-07 2023-05-07 10:00:09 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel Minor tracing updates: 2023-05-05 13:11:02 -07:00
lib A single fix for debugobjects: 2023-05-07 11:04:26 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm Reinstate the dmapool changes which were accidentally removed by 2023-05-06 11:43:08 -07:00
net Including fixes from netfilter. 2023-05-05 19:12:01 -07:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples LoongArch changes for v6.4 2023-05-04 12:40:16 -07:00
scripts Locking changes in v6.4: 2023-05-05 12:56:55 -07:00
security integrity-v6.4 2023-04-29 10:11:32 -07:00
sound sound fixes for 6.4-rc1 2023-05-06 08:07:11 -07:00
tools Disable building BPF based features by default for v6.4. 2023-05-07 11:32:18 -07:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt s390: 2023-05-01 12:06:20 -07:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap for-6.4/block-2023-05-06 2023-05-06 08:28:58 -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 A handful of late-arriving documentation fixes, plus one Spanish 2023-05-05 13:16:42 -07:00
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 fixes from netfilter. 2023-05-05 19:12:01 -07:00
Makefile Linux 6.4-rc1 2023-05-07 13:34:35 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -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 Restructured Text 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.