Linux kernel
============
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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.
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Pull io_uring fixes from Jens Axboe:
- Allow vectorized payloads for send/send-zc - like sendmsg, but
without the hassle of a msghdr.
- Fix for an integer wrap that should go to stable, spotted by syzbot.
Nothing alarming here, as you need to be root to hit this.
Nevertheless, it should get fixed.
FWIW, kudos to the syzbot crew for having much nicer reproducers now,
and with nicely annotated source code as well. This is particularly
useful as syzbot uses the raw interface rather than liburing,
historically it's been difficult to turn a syzbot reproducer into a
meaningful test case. With the recent changes, not true anymore!
* tag 'io_uring-6.17-20250808' of git://git.kernel.dk/linux:
io_uring/memmap: cast nr_pages to size_t before shifting
io_uring/net: Allow to do vectorized send
Pull spi fixes from Mark Brown:
"There's one fix here for an issue with the CS42L43 where we were
allocating a single property for client devices as just that property
rather than a terminated array of properties like we are supposed to.
We also have an update to the MAINTAINERS file for some Renesas
devices"
* tag 'spi-fix-v6.17-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: cs42l43: Property entry should be a null-terminated array
MAINTAINERS: Add entries for the RZ/V2H(P) RSPI
If the allocated size exceeds UINT_MAX, then it's necessary to cast
the mr->nr_pages value to size_t to prevent it from overflowing. In
practice this isn't much of a concern as the required memory size will
have been validated upfront, and accounted to the user. And > 4GB sizes
will be necessary to make the lack of a cast a problem, which greatly
exceeds normal user locked_vm settings that are generally in the kb to
mb range. However, if root is used, then accounting isn't done, and
then it's possible to hit this issue.
Link: https://lore.kernel.org/all/6895b298.050a0220.7f033.0059.GAE@google.com/
Cc: stable@vger.kernel.org
Reported-by: syzbot+23727438116feb13df15@syzkaller.appspotmail.com
Fixes: 087f997870a9 ("io_uring/memmap: implement mmap for regions")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull regulator fix from Mark Brown:
"This fixes an issue with the newly added code for handling large
voltage changes on regulators which require that individual voltage
changes cover a limited range, the check for convergence was broken"
* tag 'regulator-fix-v6.17-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: core: correct convergence check in regulator_set_voltage()
The software node does not specify a count of property entries, so the
array must be null-terminated.
When unterminated, this can lead to a fault in the downstream cs35l56
amplifier driver, because the node parse walks off the end of the
array into unknown memory.
Fixes: 0ca645ab5b15 ("spi: cs42l43: Add speaker id support to the bridge configuration")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220371
Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Link: https://patch.msgid.link/20250731160109.1547131-1-simont@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
At the moment you have to use sendmsg for vectorized send.
While this works it's suboptimal as it also means you need to
allocate a struct msghdr that needs to be kept alive until a
submission happens. We can remove this limitation by just
allowing to use send directly.
Signed-off-by: Norman Maurer <norman_maurer@apple.com>
Link: https://lore.kernel.org/r/20250729065952.26646-1-norman_maurer@apple.com
[axboe: remove -EINVAL return for SENDMSG and SEND_VECTORIZED]
[axboe: allow send_zc to set SEND_VECTORIZED too]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull regmap fixes from Mark Brown:
"These patches fix a lockdep issue Russell King reported with nested
regmap-irqs (unusual since regmap is generally for devices on slow
buses so devices don't get nested), plus add a missing mutex free
which I noticed while implementing a fix for that issue"
* tag 'regmap-fix-v6.17-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
regmap: irq: Avoid lockdep warnings with nested regmap-irq chips
regmap: irq: Free the regmap-irq mutex
The logic in regulator_set_voltage() which checks for a non-convergence
condition on a stepped regulator is flawed.
regulator_set_voltage() checks if the error in target voltage has increased
or decreased, and returns -EWOULDBLOCK if the error has not decreased
enough. The correct non-convergence condition is:
new_delta - delta > -rdev->constraints->max_uV_step
or equivalently:
delta - new_delta < rdev->constraints->max_uV_step
But the currently used condition is:
new_delta - delta > rdev->constraints->max_uV_step
Which may cause an infinite loop if the voltage error doesn't converge.
Fix this by correcting the convergence condition.
Suggested-by: Jon Hunter <jonathanh@nvidia.com>
Fixes: d511206dc7443 ("regulator: core: repeat voltage setting request for stepped regulators")
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Link: https://patch.msgid.link/20250729-b4-regulator-stepping-fix-v1-1-3f7b8c55d7d7@bootlin.com
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add the MAINTAINERS entries for the Renesas RZ/V2H(P) RSPI
driver.
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20250729145110.37258-1-fabrizio.castro.jz@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull sysctl updates from Joel Granados:
- Move sysctls out of the kern_table array
This is the final move of ctl_tables into their respective
subsystems. Only 5 (out of the original 50) will remain in
kernel/sysctl.c file; these handle either sysctl or common arch
variables.
By decentralizing sysctl registrations, subsystem maintainers regain
control over their sysctl interfaces, improving maintainability and
reducing the likelihood of merge conflicts.
- docs: Remove false positives from check-sysctl-docs
Stopped falsely identifying sysctls as undocumented or unimplemented
in the check-sysctl-docs script. This script can now be used to
automatically identify if documentation is missing.
* tag 'sysctl-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: (23 commits)
docs: Downgrade arm64 & riscv from titles to comment
docs: Replace spaces with tabs in check-sysctl-docs
docs: Remove colon from ctltable title in vm.rst
docs: Add awk section for ucount sysctl entries
docs: Use skiplist when checking sysctl admin-guide
docs: nixify check-sysctl-docs
sysctl: rename kern_table -> sysctl_subsys_table
kernel/sys.c: Move overflow{uid,gid} sysctl into kernel/sys.c
uevent: mv uevent_helper into kobject_uevent.c
sysctl: Removed unused variable
sysctl: Nixify sysctl.sh
sysctl: Remove superfluous includes from kernel/sysctl.c
sysctl: Remove (very) old file changelog
sysctl: Move sysctl_panic_on_stackoverflow to kernel/panic.c
sysctl: move cad_pid into kernel/pid.c
sysctl: Move tainted ctl_table into kernel/panic.c
Input: sysrq: mv sysrq into drivers/tty/sysrq.c
fork: mv threads-max into kernel/fork.c
parisc/power: Move soft-power into power.c
mm: move randomize_va_space into memory.c
...
Pull pci fix from Bjorn Helgaas:
- Fix vmd MSI interrupt domain restructure that caused crash early in
boot (Nam Cao)
* tag 'pci-v6.17-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
PCI: vmd: Fix wrong kfree() in vmd_msi_free()
While handling interrupts through regmap-irq we use a mutex to protect the
updates we are caching while genirq runs in atomic context. Russell King
reported that while running on the nVidia Jetson Xavier NX this generates
lockdep warnings since that platform has a regmap-irq for the max77686 RTC
which is a child of a max77620 which also uses regmap-irq.
[ 46.723127] rtcwake/3984 is trying to acquire lock:
[ 46.723235] ffff0000813b2c68 (&d->lock){+.+.}-{4:4}, at: regmap_irq_lock+0x18/0x24
[ 46.723452]
but task is already holding lock:
[ 46.723556] ffff00008504dc68 (&d->lock){+.+.}-{4:4}, at: regmap_irq_lock+0x18/0x24
This happens because by default lockdep uses a single lockdep class for all
mutexes initialised from a single mutex_init() call and is unable to tell
that two distinct mutex are being taken and verify that the ordering of
operations is safe. This should be a very rare situation since normally
anything using regmap-irq will be a leaf interrupt controller due to being
on a slow bus like I2C.
We can avoid these warnings by providing the lockdep key for the regmap-irq
explicitly, allocating one for each chip so that lockdep can distinguish
between them.
Thanks to Russell for the report and analysis.
Reported-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://patch.msgid.link/20250731-regmap-irq-nesting-v1-2-98b4d1bf20f0@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The function name mt6370_regualtor_register contains a spelling mistake,
fix it.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://patch.msgid.link/20250724114832.146718-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The check for ns < 0 is always false because variable ns is a u32 which
is not a signed type. Fix this by making ns a s32 type.
Fixes: cef9991e04ae ("spi: Add Amlogic SPISG driver")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://patch.msgid.link/20250725171701.839927-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull hardening fixes from Kees Cook:
"Notably, this contains the fix for for the GCC __init mess I created
with the kstack_erase annotations.
- staging: media: atomisp: Fix stack buffer overflow in
gmin_get_var_int().
I was asked to carry this fix, so here it is. :)
- fortify: Fix incorrect reporting of read buffer size
- kstack_erase: Fix missed export of renamed KSTACK_ERASE_CFLAGS
- compiler_types: Provide __no_kstack_erase to disable coverage only
on Clang"
* tag 'hardening-v6.17-rc1-fix1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
compiler_types: Provide __no_kstack_erase to disable coverage only on Clang
fortify: Fix incorrect reporting of read buffer size
kstack_erase: Fix missed export of renamed KSTACK_ERASE_CFLAGS
staging: media: atomisp: Fix stack buffer overflow in gmin_get_var_int()
Remove the title string ("====") from under arm64 & riscv and move them
to a commment under the perf_user_access sysctl. They are explanations,
*not* sysctls themselves
This effectively removes these two strings from appearing as not
implemented when the check-sysctl-docs script is run
Signed-off-by: Joel Granados <joel.granados@kernel.org>