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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.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Pull s390 fixes from Vasily Gorbik:
- Add a few notrace annotations to avoid potential crashes when
switching ftrace tracers.
- Avoid setting affinity for floating irqs in pci code.
- Fix build issue found by kbuild test robot.
* tag 's390-5.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/protvirt: fix compilation issue
s390/pci: do not set affinity for floating irqs
s390/ftrace: fix potential crashes when switching tracers
Pull powerpc fixes from Michael Ellerman:
- One important fix for a bug in the way we find the cache-line size
from the device tree, which was leading to the wrong size being
reported to userspace on some platforms.
- A fix for 8xx STRICT_KERNEL_RWX which was leaving TLB entries around
leading to a window at boot when the strict mapping wasn't enforced.
- A fix to enable our KUAP (kernel user access prevention) debugging on
PPC32.
- A build fix for clang in lib/mpi.
Thanks to: Chris Packham, Christophe Leroy, Nathan Chancellor, Qian Cai.
* tag 'powerpc-5.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
lib/mpi: Fix building for powerpc with clang
powerpc/mm: Fix CONFIG_PPC_KUAP_DEBUG on PPC32
powerpc/8xx: Fix STRICT_KERNEL_RWX startup test failure
powerpc/setup_64: Set cache-line-size based on cache-block-size
The kernel fails to compile with CONFIG_PROTECTED_VIRTUALIZATION_GUEST
set but CONFIG_KVM unset.
This patch fixes the issue by making the needed variable always available.
Link: https://lkml.kernel.org/r/20200423120114.2027410-1-imbrenda@linux.ibm.com
Fixes: a0f60f843199 ("s390/protvirt: Add sysfs firmware interface for Ultravisor information")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Philipp Rudo <prudo@linux.ibm.com>
Suggested-by: Philipp Rudo <prudo@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull more Devicetree fixes from Rob Herring:
"A couple of schema and kbuild fixes"
* tag 'devicetree-fixes-for-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
dt-bindings: phy: qcom-qusb2: Fix defaults
dt-bindings: Fix erroneous 'additionalProperties'
dt-bindings: Fix command line length limit calling dt-mk-schema
dt-bindings: Re-enable core schemas for dtbs_check
0day reports over and over on an powerpc randconfig with clang:
lib/mpi/generic_mpih-mul1.c:37:13: error: invalid use of a cast in a
inline asm context requiring an l-value: remove the cast or build with
-fheinous-gnu-extensions
Remove the superfluous casts, which have been done previously for x86
and arm32 in commit dea632cadd12 ("lib/mpi: fix build with clang") and
commit 7b7c1df2883d ("lib/mpi/longlong.h: fix building with 32-bit
x86").
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/ClangBuiltLinux/linux/issues/991
Link: https://lore.kernel.org/r/20200413195041.24064-1-natechancellor@gmail.com
with the introduction of CPU directed interrupts the kernel
parameter pci=force_floating was introduced to fall back
to the previous behavior using floating irqs.
However we were still setting the affinity in that case,
both in __irq_alloc_descs() and via the irq_set_affinity
callback in struct irq_chip.
For the former only set the affinity in the directed case.
The latter is explicitly set in zpci_directed_irq_init()
so we can just leave it unset for the floating case.
Fixes: e979ce7bced2 ("s390/pci: provide support for CPU directed interrupts")
Co-developed-by: Alexander Schmidt <alexs@linux.ibm.com>
Signed-off-by: Alexander Schmidt <alexs@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull pid leak fix from Eric Biederman:
"Oleg noticed that put_pid(thread_pid) was not getting called when proc
was not compiled in.
Let's get that fixed before 5.7 is released and causes problems for
anyone"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
proc: Put thread_pid in release_task not proc_flush_pid
The defaults listed in the bindings don't match what the code is
actually doing. Presumably existing users care more about keeping
existing behavior the same, so change the bindings to match the code
in Linux.
The "qcom,preemphasis-level" default has been wrong for quite a long
time (May 2018). The other two were recently added.
As some evidence that these values are wrong, this is from the Linux
driver:
- qcom,preemphasis-level: sets "PORT_TUNE1", lower 2 bits. Driver
programs PORT_TUNE1 to 0x30 by default and (0x30 & 0x3) = 0.
- qcom,bias-ctrl-value: sets "PLL_BIAS_CONTROL_2", lower 6 bits.
Driver programs PLL_BIAS_CONTROL_2 to 0x20 by default and (0x20 &
0x3f) = 0x20 = 32.
- qcom,hsdisc-trim-value: sets "PORT_TUNE2", lower 2 bits. Driver
programs PORT_TUNE2 to 0x29 by default and (0x29 & 0x3) = 1.
Fixes: 1e6f134eb67a ("dt-bindings: phy: qcom-qusb2: Add support for overriding Phy tuning parameters")
Fixes: a8b70ccf10e3 ("dt-bindings: phy-qcom-usb2: Add support to override tuning values")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Rob Herring <robh@kernel.org>
CONFIG_PPC_KUAP_DEBUG is not selectable because it depends on PPC_32
which doesn't exists.
Fixing it leads to a deadlock due to a vital register getting
clobbered in _switch().
Change dependency to PPC32 and use r0 instead of r4 in _switch()
Fixes: e2fb9f544431 ("powerpc/32: Prepare for Kernel Userspace Access Protection")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/540242f7d4573f7cdf1b3bf46bb35f743b2cd68f.1587124651.git.christophe.leroy@c-s.fr
Switching tracers include instruction patching. To prevent that a
instruction is patched while it's read the instruction patching is done
in stop_machine 'context'. This also means that any function called
during stop_machine must not be traced. Thus add 'notrace' to all
functions called within stop_machine.
Fixes: 1ec2772e0c3c ("s390/diag: add a statistic for diagnose calls")
Fixes: 38f2c691a4b3 ("s390: improve wait logic of stop_machine")
Fixes: 4ecf0a43e729 ("processor: get rid of cpu_relax_yield")
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Pull timer fixlet from Ingo Molnar:
"A single fix for a comment that may show up in DocBook output"
* tag 'timers-urgent-2020-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
vdso/datapage: Use correct clock mode name in comment
Oleg pointed out that in the unlikely event the kernel is compiled
with CONFIG_PROC_FS unset that release_task will now leak the pid.
Move the put_pid out of proc_flush_pid into release_task to fix this
and to guarantee I don't make that mistake again.
When possible it makes sense to keep get and put in the same function
so it can easily been seen how they pair up.
Fixes: 7bc3e6e55acf ("proc: Use a list of inodes to flush from proc")
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
There's several cases of json-schema 'additionalProperties' at the wrong
indentation level which has the effect of making them DT properties. This
is harmless, but let's fix them so a meta-schema check for this can be
added.
In all the cases, either the 'additionalProperties' was extra or doesn't
work because there's a $ref to more properties. In the latter case, we
can use 'unevaluatedProperties' instead.
Reported-by: Iskren Chernev <iskren.chernev@gmail.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Saravanan Sekar <sravanhome@gmail.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
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