Commit 9c44bc03ff ("softlockup: allow panic on lockup") added the
softlockup_panic sysctl, but didn't add information about it to the file
Documentation/admin-guide/sysctl/kernel.rst (which in that time certainly
wasn't rst and had other name!).
This patch just adds the respective documentation and references it from
the corresponding entry in Documentation/admin-guide/kernel-parameters.txt.
This patch was strongly based on Scott Wood's commit d22881dc13
("Documentation: Better document the hardlockup_panic sysctl").
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Link: https://lore.kernel.org/r/20200310183649.23163-1-gpiccoli@canonical.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The virt_mechanism reference there points to a section
called elsewhere (Virtualization mitigation). Also, it is
not used anywere.
Besides that, it conflicts with a label with the same name
inside:
Documentation/admin-guide/hw-vuln/mds.rst
Perhaps added due to some cut-and-paste?
Anyway, as this is not used, let's just get rid of it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/681c8e2916bf4943ac2277f181668bfbc5fdbc01.1583250595.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Trim the title a bit, since it's relatively long. Add `binfmt_misc` to
make it easier to search for the feature by its common name.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20200308210935.7273-1-j.neuschaefer@gmx.net
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Thermal pressure follows pelt signals which means the decay period for
thermal pressure is the default pelt decay period. Depending on SoC
characteristics and thermal activity, it might be beneficial to decay
thermal pressure slower, but still in-tune with the pelt signals. One way
to achieve this is to provide a command line parameter to set a decay
shift parameter to an integer between 0 and 10.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-10-thara.gopinath@linaro.org
Update filter.txt and admin-guide to mention the BPF JIT for RV32G.
Co-developed-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luke Nelson <luke.r.nels@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Björn Töpel <bjorn.topel@gmail.com>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20200305050207.4159-4-luke.r.nels@gmail.com
With the addition of fw_devlink kernel commandline option, of_devlink is
redundant and not useful anymore. So, delete it.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-6-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fwnode_operations.add_links allows creating device links from
information provided by firmware.
fwnode_operations.add_links is currently implemented only by
OF/devicetree code and a specific case of efi. However, there's nothing
preventing ACPI or other firmware types from implementing it.
The OF implementation is currently controlled by a kernel commandline
parameter called of_devlink.
Since this feature is generic isn't limited to OF, add a generic
fw_devlink kernel commandline parameter to control this feature across
firmware types.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When converting and moving nfsroot.txt to nfsroot.rst the references to
the old text file was not updated to match the change, fix this.
Fixes: f9a9349846 ("Documentation: nfsroot.txt: convert to ReST")
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200212181332.520545-1-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The set of WQ_SYSFS workqueues should be displayed using
"ls /sys/devices/virtual/workqueue", add the missing '/'.
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20200225124052.1506-1-yuzenghui@huawei.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Annotate references to other documents to make them clickable.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-6-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
We need literal sections otherwise the entire example is rendered
as a single line.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-5-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
We need a literal section, like few paragraphs below.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-4-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
If there is an empty line between item and description
Sphinx does not emphasize the item. First half of the
list does not have the empty line and is emphasized
correctly.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-3-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Fix tabs vs spaces issue which cases the line to be considered
a new list entry.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-2-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
There are three legacy driver documents in Documentation/cpu-freq/
that were added years ago and converting them each to the .rst
format is rather pointless, even though there is some value in
preserving them. However, if they are preserved, they need to go
into the admin-guide part of cpufreq documentation where they belong
(at least to a certain extent).
To preserve them with minimum amount of changes and put them into the
right place, and make it possible to process them into HTML (and other
formats) along with the rest of the documentation, move them each
as a "literal text" block into a separate section of a single .rst
"wrapper" file under Documentation/admin-guide/pm/.
While at it, repair the PCC specification URL in one of them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix a couple of configuration issues in the ACPI watchdog (WDAT)
driver (Mika Westerberg) and make it possible to disable that
driver at boot time in case it still does not work as
expected (Jean Delvare).
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Merge tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes from Rafael Wysocki:
"Fix a couple of configuration issues in the ACPI watchdog (WDAT)
driver (Mika Westerberg) and make it possible to disable that driver
at boot time in case it still does not work as expected (Jean
Delvare)"
* tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: watchdog: Set default timeout in probe
ACPI: watchdog: Fix gas->access_width usage
ACPICA: Introduce ACPI_ACCESS_BYTE_WIDTH() macro
ACPI: watchdog: Allow disabling WDAT at boot
Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it needs large amounts of memory and will disable
some features like STP time sync for the lpar.
Extend ultravisor info definitions and expose it via uv_info struct
filled in during startup.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Change in API of bootconfig (before it comes live in a release)
- Have a magic value "BOOTCONFIG" in initrd to know a bootconfig exists
- Set CONFIG_BOOT_CONFIG to 'n' by default
- Show error if "bootconfig" on cmdline but not compiled in
- Prevent redefining the same value
- Have a way to append values
- Added a SELECT BLK_DEV_INITRD to fix a build failure
Synthetic event fixes:
- Switch to raw_smp_processor_id() for recording CPU value in preempt
section. (No care for what the value actually is)
- Fix samples always recording u64 values
- Fix endianess
- Check number of values matches number of fields
- Fix a printing bug
Fix of trace_printk() breaking postponed start up tests
Make a function static that is only used in a single file.
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Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing and bootconfig updates:
"Fixes and changes to bootconfig before it goes live in a release.
Change in API of bootconfig (before it comes live in a release):
- Have a magic value "BOOTCONFIG" in initrd to know a bootconfig
exists
- Set CONFIG_BOOT_CONFIG to 'n' by default
- Show error if "bootconfig" on cmdline but not compiled in
- Prevent redefining the same value
- Have a way to append values
- Added a SELECT BLK_DEV_INITRD to fix a build failure
Synthetic event fixes:
- Switch to raw_smp_processor_id() for recording CPU value in preempt
section. (No care for what the value actually is)
- Fix samples always recording u64 values
- Fix endianess
- Check number of values matches number of fields
- Fix a printing bug
Fix of trace_printk() breaking postponed start up tests
Make a function static that is only used in a single file"
* tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
bootconfig: Add append value operator support
bootconfig: Prohibit re-defining value on same key
bootconfig: Print array as multiple commands for legacy command line
bootconfig: Reject subkey and value on same parent key
tools/bootconfig: Remove unneeded error message silencer
bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
bootconfig: Set CONFIG_BOOT_CONFIG=n by default
tracing: Clear trace_state when starting trace
bootconfig: Mark boot_config_checksum() static
tracing: Disable trace_printk() on post poned tests
tracing: Have synthetic event test use raw_smp_processor_id()
tracing: Fix number printing bug in print_synth_event()
tracing: Check that number of vals matches number of synth event fields
tracing: Make synth_event trace functions endian-correct
tracing: Make sure synth_event_trace() example always uses u64
This script allows sysctl documentation to be checked against the
kernel source code, to identify missing or obsolete entries. Running
it against 5.5 shows for example that sysctl/kernel.rst has two
obsolete entries and is missing 52 entries.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Based on the implementation in arch/x86/kernel/acpi/sleep.c, in
particular the acpi_sleep_setup() function.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,
foo = bar
...
foo += baz
Then the key "foo" has "bar" and "baz" values as an array.
Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently, bootconfig adds a new value on the existing key to the tail of an
array. But this looks a bit confusing because an admin can easily rewrite
the original value in the same config file.
This rejects the following value re-definition.
key = value1
...
key = value2
You should rewrite value1 to value2 in this case.
Link: http://lkml.kernel.org/r/158227282199.12842.10110929876059658601.stgit@devnote2
Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Fixed spelling of arraies to arrays ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In theory, RCU-hotplug operations are supposed to work as soon as there
is more than one CPU online. However, in practice, in normal production
there is no way to make them happen until userspace is up and running.
Besides which, on smaller systems, rcutorture doesn't start doing hotplug
operations until 30 seconds after the start of boot, which on most
systems also means the better part of 30 seconds after the end of boot.
This commit therefore provides a new torture.disable_onoff_at_boot kernel
boot parameter that suppresses CPU-hotplug torture operations until
about the time that init is spawned.
Of course, if you know of a need for boottime CPU-hotplug operations,
then you should avoid passing this argument to any of the torture tests.
You might also want to look at the splats linked to below.
Link: https://lore.kernel.org/lkml/20191206185208.GA25636@paulmck-ThinkPad-P72/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In normal production, an RCU CPU stall warning at boottime is often
just as bad as at any other time. In fact, given the desire for fast
boot, any sort of long-term stall at boot is a bad idea. However,
heavy rcutorture testing on large hyperthreaded systems can generate
boottime RCU CPU stalls as a matter of course. This commit therefore
provides a kernel boot parameter that suppresses reporting of boottime
RCU CPU stall warnings and similarly of rcutorture writer stalls.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In default configutions, RCU currently waits at least 100 milliseconds
before asking cond_resched() and/or resched_rcu() for help seeking
quiescent states to end a grace period. But 100 milliseconds can be
one good long time during an RCU callback flood, for example, as can
happen when user processes repeatedly open and close files in a tight
loop. These 100-millisecond gaps in successive grace periods during a
callback flood can result in excessive numbers of callbacks piling up,
unnecessarily increasing memory footprint.
This commit therefore asks cond_resched() and/or resched_rcu() for help
as early as the first FQS scan when at least one of the CPUs has more
than 20,000 callbacks queued, a number that can be changed using the new
rcutree.qovld kernel boot parameter. An auxiliary qovld_calc variable
is used to avoid acquisition of locks that have not yet been initialized.
Early tests indicate that this reduces the RCU-callback memory footprint
during rcutorture floods by from 50% to 4x, depending on configuration.
Reported-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reported-by: Tejun Heo <tj@kernel.org>
[ paulmck: Fix bug located by Qian Cai. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Dexuan Cui <decui@microsoft.com>
Tested-by: Qian Cai <cai@lca.pw>
Reject if a value node is mixed with subkey node on same
parent key node.
A value node can not co-exist with subkey node under some key
node, e.g.
key = value
key.subkey = another-value
This is not be allowed because bootconfig API is not designed
to handle such case.
Link: http://lkml.kernel.org/r/158220115232.26565.7792340045009731803.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add bootconfig magic word to the end of bootconfig on initrd
image for indicating explicitly the bootconfig is there.
Also tools/bootconfig treats wrong size or wrong checksum or
parse error as an error, because if there is a bootconfig magic
word, there must be a bootconfig.
The bootconfig magic word is "#BOOTCONFIG\n", 12 bytes word.
Thus the block image of the initrd file with bootconfig is
as follows.
[Initrd][bootconfig][size][csum][#BOOTCONFIG\n]
Link: http://lkml.kernel.org/r/158220112263.26565.3944814205960612841.stgit@devnote2
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A split-lock occurs when an atomic instruction operates on data that spans
two cache lines. In order to maintain atomicity the core takes a global bus
lock.
This is typically >1000 cycles slower than an atomic operation within a
cache line. It also disrupts performance on other cores (which must wait
for the bus lock to be released before their memory operations can
complete). For real-time systems this may mean missing deadlines. For other
systems it may just be very annoying.
Some CPUs have the capability to raise an #AC trap when a split lock is
attempted.
Provide a command line option to give the user choices on how to handle
this:
split_lock_detect=
off - not enabled (no traps for split locks)
warn - warn once when an application does a
split lock, but allow it to continue
running.
fatal - Send SIGBUS to applications that cause split lock
On systems that support split lock detection the default is "warn". Note
that if the kernel hits a split lock in any mode other than "off" it will
OOPs.
One implementation wrinkle is that the MSR to control the split lock
detection is per-core, not per thread. This might result in some short
lived races on HT systems in "warn" mode if Linux tries to enable on one
thread while disabling on the other. Race analysis by Sean Christopherson:
- Toggling of split-lock is only done in "warn" mode. Worst case
scenario of a race is that a misbehaving task will generate multiple
#AC exceptions on the same instruction. And this race will only occur
if both siblings are running tasks that generate split-lock #ACs, e.g.
a race where sibling threads are writing different values will only
occur if CPUx is disabling split-lock after an #AC and CPUy is
re-enabling split-lock after *its* previous task generated an #AC.
- Transitioning between off/warn/fatal modes at runtime isn't supported
and disabling is tracked per task, so hardware will always reach a steady
state that matches the configured mode. I.e. split-lock is guaranteed to
be enabled in hardware once all _TIF_SLD threads have been scheduled out.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200126200535.GB30377@agluck-desk2.amr.corp.intel.com
Fix Sphinx format warnings in fan_performace_states.rst
by adding indentation.
Documentation/admin-guide/acpi/fan_performance_states.rst:21: WARNING: Literal block ends without a blank line; unexpected unindent.
Documentation/admin-guide/acpi/fan_performance_states.rst:41: WARNING: Literal block expected; none found.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When both the documentation and the data files lived in
Documentation/EDID, this wasn't necessary, but both have
been moved to other directories in the meantime.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This document describes actions that an admin can do, rather than
interfaces available to driver developers, so admin-guide seems to
be a more appropriate place for it.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The description of panic doesn’t cover all the supported scenarios;
this patch fixes that, describing the three possibilities (no reboot,
immediate reboot, reboot after a delay).
Based on the implementation in kernel/panic.c.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This describes the SPARC-specific stop-a sysctl entry, which was
previously listed in kernel.rst but not documented.
Base on the implementation in arch/sparc/kernel/setup_{32,64}.c and
kernel/panic.c.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This adds short descriptions of msgmax, msgmnb, msgmni, and shmmni,
which were previously listed in kernel.rst but not described.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The l2cr sysctl entry was removed in commit c2f3dabefa ("sysctl:
kill binary sysctl KERN_PPC_L2CR"), this removes the corresponding
documentation.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This fits nicely in sysctl/kernel.rst, merge it (and rephrase it)
instead of linking to it.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This updates sysctl/kernel.rst to use ReStructured Text more fully:
* the list of files is now the table of contents (old entries with no
corresponding sections are added as empty sections for now);
* code references and commands are formatted as code, except for
function names which end up linked to the appropriate documentation;
* links are used to point to other documentation and other sections;
* tables are used to make lists of values more readable (as already
done for some sections);
* in heavily-reworked paragraphs, sentences are wrapped individually,
to make future diffs easier to read.
The first mention of the kernel version is dropped. The second
mention, saying that the document is accurate for 2.2, is preserved
for now; I will update that once the document really is accurate for a
current kernel release.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
cmdlinepart.c has been moved to drivers/mtd/parsers/.
Fixes: a3f12a35c9 ("mtd: parsers: Move CMDLINE parser")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Update the PM QoS documentation to reflect the previous code changes
regarding the removal of PM QoS classes and the CPU latency QoS API
rework.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
There is somehow no description of %c corename format specifier for
/proc/sys/kernel/core_pattern. The %c corename format specifier is
used by user-space application such as systemd-coredump, so it should
be documented.
To find where %c is handled in the kernel source code, look at
function format_corename() in fs/coredump.c.
Signed-off-by: HATAYAMA Daisuke <d.hatayama@fujitsu.com>
Link: https://lore.kernel.org/r/TYAPR01MB4014714BB2ACE425BB6EC6B7951A0@TYAPR01MB4014.jpnprd01.prod.outlook.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
With the realization that having debugfs enabled on "production" systems
is generally not a good idea, debugfs is being disabled from more and
more platforms over time. However, the functionality of dynamic
debugging still is needed at times, and since it relies on debugfs for
its user api, having debugfs disabled also forces dynamic debug to be
disabled.
To get around this, also create the "control" file for dynamic_debug in
procfs. This allows people turn on debugging as needed at runtime for
individual driverfs and subsystems.
Reported-by: many different companies
Cc: Jason Baron <jbaron@akamai.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200210211142.GB1373304@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
