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.
code
Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
For self-hosted knots, clone URLs may differ based on your setup.
Pull ARC fixes from Vineet Gupta:
- Sundry build and misc fixes
* tag 'arc-6.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: build: Try to guess GCC variant of cross compiler
ARC: bpf: Correct conditional check in 'check_jmp_32'
ARC: dts: Replace deprecated snps,nr-gpios property for snps,dw-apb-gpio-port devices
ARC: build: Use __force to suppress per-CPU cmpxchg warnings
ARC: fix reference of dependency for PAE40 config
ARC: build: disallow invalid PAE40 + 4K page config
arc: rename aux.h to arc_aux.h
Pull EFI fixes from Ard Biesheuvel:
- Limit EFI zboot to GZIP and ZSTD before it comes in wider use
- Fix inconsistent error when looking up a non-existent file in
efivarfs with a name that does not adhere to the NAME-GUID format
- Drop some unused code
* tag 'efi-fixes-for-v6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
efi/esrt: remove esre_attribute::store()
efivarfs: Fix error on non-existent file
efi/zboot: Limit compression options to GZIP and ZSTD
ARC GCC compiler is packaged starting from Fedora 39i and the GCC
variant of cross compile tools has arc-linux-gnu- prefix and not
arc-linux-. This is causing that CROSS_COMPILE variable is left unset.
This change allows builds without need to supply CROSS_COMPILE argument
if distro package is used.
Before this change:
$ make -j 128 ARCH=arc W=1 drivers/infiniband/hw/mlx4/
gcc: warning: ‘-mcpu=’ is deprecated; use ‘-mtune=’ or ‘-march=’ instead
gcc: error: unrecognized command-line option ‘-mmedium-calls’
gcc: error: unrecognized command-line option ‘-mlock’
gcc: error: unrecognized command-line option ‘-munaligned-access’
[1] https://packages.fedoraproject.org/pkgs/cross-gcc/gcc-arc-linux-gnu/index.html
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
Pull i2c fixes from Wolfram Sang:
"i2c host fixes: PNX used the wrong unit for timeouts, Nomadik was
missing a sentinel, and RIIC was missing rounding up"
* tag 'i2c-for-6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: riic: Always round-up when calculating bus period
i2c: nomadik: Add missing sentinel to match table
i2c: pnx: Fix timeout in wait functions
esre_attribute::store() is not needed since commit af97a77bc01c (efi:
Move some sysfs files to be read-only by root). Drop it.
Found by https://github.com/jirislaby/clang-struct.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The original code checks 'if (ARC_CC_AL)', which is always true since
ARC_CC_AL is a constant. This makes the check redundant and likely
obscures the intention of verifying whether the jump is conditional.
Updates the code to check cond == ARC_CC_AL instead, reflecting the intent
to differentiate conditional from unconditional jumps.
Suggested-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Acked-by: Shahab Vahedi <list+bpf@vahedi.org>
Signed-off-by: Hardevsinh Palaniya <hardevsinh.palaniya@siliconsignals.io>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
Pull EDAC fix from Borislav Petkov:
- Make sure amd64_edac loads successfully on certain Zen4 memory
configurations
* tag 'edac_urgent_for_v6.13_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/amd64: Simplify ECC check on unified memory controllers
i2c-host-fixes for v6.13-rc3
- Replaced jiffies with msec for timeout calculations.
- Added a sentinel to the 'of_device_id' array in Nomadik.
- Rounded up bus period calculation in RIIC.
When looking up a non-existent file, efivarfs returns -EINVAL if the
file does not conform to the NAME-GUID format and -ENOENT if it does.
This is caused by efivars_d_hash() returning -EINVAL if the name is not
formatted correctly. This error is returned before simple_lookup()
returns a negative dentry, and is the error value that the user sees.
Fix by removing this check. If the file does not exist, simple_lookup()
will return a negative dentry leading to -ENOENT and efivarfs_create()
already has a validity check before it creates an entry (and will
correctly return -EINVAL)
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: <stable@vger.kernel.org>
[ardb: make efivarfs_valid_name() static]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
snps,dw-apb-gpio-port is deprecated since commit ef42a8da3cf3
("dt-bindings: gpio: dwapb: Add ngpios property support"). The
respective driver supports this since commit 7569486d79ae ("gpio: dwapb:
Add ngpios DT-property support") which is included in Linux v5.10-rc1.
This change was created using
git grep -l snps,nr-gpios arch/arc/boot/dts | xargs perl -p -i -e 's/\bsnps,nr-gpios\b/ngpios/
.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
Pull irq fixes from Borislav Petkov:
- Disable the secure programming interface of the GIC500 chip in the
RK3399 SoC to fix interrupt priority assignment and even make a dead
machine boot again when the gic-v3 driver enables pseudo NMIs
- Correct the declaration of a percpu variable to fix several sparse
warnings
* tag 'irq_urgent_for_v6.13_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3: Work around insecure GIC integrations
irqchip/gic: Correct declaration of *percpu_base pointer in union gic_base
The intent of the check is to see whether at least one UMC has ECC
enabled. So do that instead of tracking which ones are enabled in masks
which are too small in size anyway and lead to not loading the driver on
Zen4 machines with UMCs enabled over UMC8.
Fixes: e2be5955a886 ("EDAC/amd64: Add support for AMD Family 19h Models 10h-1Fh and A0h-AFh")
Reported-by: Avadhut Naik <avadhut.naik@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Avadhut Naik <avadhut.naik@amd.com>
Reviewed-by: Avadhut Naik <avadhut.naik@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20241210212054.3895697-1-avadhut.naik@amd.com
Currently, the RIIC driver may run the I2C bus faster than requested,
which may cause subtle failures. E.g. Biju reported a measured bus
speed of 450 kHz instead of the expected maximum of 400 kHz on RZ/G2L.
The initial calculation of the bus period uses DIV_ROUND_UP(), to make
sure the actual bus speed never becomes faster than the requested bus
speed. However, the subsequent division-by-two steps do not use
round-up, which may lead to a too-small period, hence a too-fast and
possible out-of-spec bus speed. E.g. on RZ/Five, requesting a bus speed
of 100 resp. 400 kHz will yield too-fast target bus speeds of 100806
resp. 403226 Hz instead of 97656 resp. 390625 Hz.
Fix this by using DIV_ROUND_UP() in the subsequent divisions, too.
Tested on RZ/A1H, RZ/A2M, and RZ/Five.
Fixes: d982d66514192cdb ("i2c: riic: remove clock and frequency restrictions")
Reported-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: <stable@vger.kernel.org> # v4.15+
Link: https://lore.kernel.org/r/c59aea77998dfea1b4456c4b33b55ab216fcbf5e.1732284746.git.geert+renesas@glider.be
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
For historical reasons, the legacy decompressor code on various
architectures supports 7 different compression types for the compressed
kernel image.
EFI zboot is not a compression library museum, and so the options can be
limited to what is likely to be useful in practice:
- GZIP is tried and tested, and is still one of the fastest at
decompression time, although the compression ratio is not very high;
moreover, Fedora is already shipping EFI zboot kernels for arm64 that
use GZIP, and QEMU implements direct support for it when booting a
kernel without firmware loaded;
- ZSTD has a very high compression ratio (although not the highest), and
is almost as fast as GZIP at decompression time.
Reducing the number of options makes it less of a hassle for other
consumers of the EFI zboot format (such as QEMU today, and kexec in the
future) to support it transparently without having to carry 7 different
decompression libraries.
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Currently, the cast of the first argument to cmpxchg_emu_u8() drops the
__percpu address-space designator, which results in sparse complaints
when applying cmpxchg() to per-CPU variables in ARC. Therefore, use
__force to suppress these complaints, given that this does not pertain
to cmpxchg() semantics, which are plently well-defined on variables in
general, whether per-CPU or otherwise.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202409251336.ToC0TvWB-lkp@intel.com/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: <linux-snps-arc@lists.infradead.org>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>