This parameter introduced several years ago in the XHCI host controller
driver was somehow left undocumented. Add a few lines in the kernel
parameters text.
Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Update Documentation/kbuild/kconfig.txt, which mostly contains
user help for using the kernel config tools.
- Add mention of 'nconfig' embedded help text.
- Make the section on new config symbols readable.
- Correct how to find menuconfig search help.
- Add section on 'nconfig' usage.
- Mention that gconfig has multiple viewing modes/options.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Removed Kbuild documentation for INSTALL_FW_PATH.
The kbuild symbol INSTALL_FW_PATH was removed from Kbuild tools in
September 2017 (for 4.14) but the symbol was not deleted from
the kbuild documentation, so do that now.
Fixes: 5620a0d1aa ("firmware: delete in-kernel firmware")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org # 4.14+
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The supported alias for building sparc 32-bit is "sparc32",
not "sparc", so update the alias documentation for that.
Just using "sparc" produces a 64-bit config file.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
In Kbuild documentation, add alias for 64-bit sh ARCH ("sh64")
to the list of ARCH aliases.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The interconnects on omap variants have configuration registers.
There are registers for a link agent, one or more interconnect
agent, and an optional access protection.
Let's also update the example for omap4 l4 per instance as it
has multiple interconnect agent registers.
For more information, see chapter "Interconnect" in TI techical
reference manuals.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
A patchset worked out together with Peter Zijlstra. Ingo is OK with taking
it through the DRM tree:
This is a small fallout from a work to allow batching WW mutex locks and
unlocks.
Our Wound-Wait mutexes actually don't use the Wound-Wait algorithm but
the Wait-Die algorithm. One could perhaps rename those mutexes tree-wide to
"Wait-Die mutexes" or "Deadlock Avoidance mutexes". Another approach suggested
here is to implement also the "Wound-Wait" algorithm as a per-WW-class
choice, as it has advantages in some cases. See for example
http://www.mathcs.emory.edu/~cheung/Courses/554/Syllabus/8-recv+serial/deadlock-compare.html
Now Wound-Wait is a preemptive algorithm, and the preemption is implemented
using a lazy scheme: If a wounded transaction is about to go to sleep on
a contended WW mutex, we return -EDEADLK. That is sufficient for deadlock
prevention. Since with WW mutexes we also require the aborted transaction to
sleep waiting to lock the WW mutex it was aborted on, this choice also provides
a suitable WW mutex to sleep on. If we were to return -EDEADLK on the first
WW mutex lock after the transaction was wounded whether the WW mutex was
contended or not, the transaction might frequently be restarted without a wait,
which is far from optimal. Note also that with the lazy preemption scheme,
contrary to Wait-Die there will be no rollbacks on lock contention of locks
held by a transaction that has completed its locking sequence.
The modeset locks are then changed from Wait-Die to Wound-Wait since the
typical locking pattern of those locks very well matches the criterion for
a substantial reduction in the number of rollbacks. For reservation objects,
the benefit is more unclear at this point and they remain using Wait-Die.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703105339.4461-1-thellstrom@vmware.com
This adds what should be a stable interface to read GPU
load from userspace.
(v2): Fix comments and name of file per recommendations.
(v3): Add chapter to amdgpu.rst as well.
Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Acked-by: Slava Abramov <slava.abramov@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Allow setting a clock called 'extclk' in the device of the ssp-dai
device. If specified, this clock will be set to the mclk rate from the
DAI's .set_sysclk() callback. The DAI will also configure itself to
use that external clock.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Add a mitigation mode parameter "vmentry_l1d_flush" for CVE-2018-3620, aka
L1 terminal fault. The valid arguments are:
- "always" L1D cache flush on every VMENTER.
- "cond" Conditional L1D cache flush, explained below
- "never" Disable the L1D cache flush mitigation
"cond" is trying to avoid L1D cache flushes on VMENTER if the code executed
between VMEXIT and VMENTER is considered safe, i.e. is not bringing any
interesting information into L1D which might exploited.
[ tglx: Split out from a larger patch ]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If the L1TF CPU bug is present we allow the KVM module to be loaded as the
major of users that use Linux and KVM have trusted guests and do not want a
broken setup.
Cloud vendors are the ones that are uncomfortable with CVE 2018-3620 and as
such they are the ones that should set nosmt to one.
Setting 'nosmt' means that the system administrator also needs to disable
SMT (Hyper-threading) in the BIOS, or via the 'nosmt' command line
parameter, or via the /sys/devices/system/cpu/smt/control. See commit
05736e4ac1 ("cpu/hotplug: Provide knobs to control SMT").
Other mitigations are to use task affinity, cpu sets, interrupt binding,
etc - anything to make sure that _only_ the same guests vCPUs are running
on sibling threads.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Enabling HARDENED_USERCOPY may cause measurable regressions in networking
performance: up to 8% under UDP flood.
I ran a small packet UDP flood using pktgen vs. a host b2b connected. On
the receiver side the UDP packets are processed by a simple user space
process that just reads and drops them:
https://github.com/netoptimizer/network-testing/blob/master/src/udp_sink.c
Not very useful from a functional PoV, but it helps to pin-point
bottlenecks in the networking stack.
When running a kernel with CONFIG_HARDENED_USERCOPY=y, I see a 5-8%
regression in the receive tput, compared to the same kernel without this
option enabled.
With CONFIG_HARDENED_USERCOPY=y, perf shows ~6% of CPU time spent
cumulatively in __check_object_size (~4%) and __virt_addr_valid (~2%).
The call-chain is:
__GI___libc_recvfrom
entry_SYSCALL_64_after_hwframe
do_syscall_64
__x64_sys_recvfrom
__sys_recvfrom
inet_recvmsg
udp_recvmsg
__check_object_size
udp_recvmsg() actually calls copy_to_iter() (inlined) and the latters
calls check_copy_size() (again, inlined).
A generic distro may want to enable HARDENED_USERCOPY in their default
kernel config, but at the same time, such distro may want to be able to
avoid the performance penalties in with the default configuration and
disable the stricter check on a per-boot basis.
This change adds a boot parameter that conditionally disables
HARDENED_USERCOPY via "hardened_usercopy=off".
Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Add a new control V4L2_CID_MPEG_VIDEO_VP9_PROFILE for VP9 profiles. This control
allows selecting the desired profile for VP9 encoder and querying for supported
profiles by VP9 encoder/decoder.
Though this control is similar to V4L2_CID_MPEG_VIDEO_VP8_PROFILE, we need to
separate this control from it because supported profiles usually differ between
VP8 and VP9.
Signed-off-by: Keiichi Watanabe <keiichiw@chromium.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add a menu control V4L2_CID_MPEG_VIDEO_VP8_PROFILE for VP8 profile and make
V4L2_CID_MPEG_VIDEO_VPX_PROFILE an alias of it. This new control is used to
select the desired profile for VP8 encoder and query for supported profiles by
VP8 encoder/decoder.
Though we have originally a control V4L2_CID_MPEG_VIDEO_VPX_PROFILE and its name
contains 'VPX', it works only for VP8 because supported profiles usually differ
between VP8 and VP9. In addition, this control cannot be used for querying since
it is not a menu control but an integer control, which cannot return an
arbitrary set of supported profiles.
The new control V4L2_CID_MPEG_VIDEO_VP8_PROFILE is a menu control as with
controls for other codec profiles. (e.g. H264)
In addition, this patch also fixes the use of V4L2_CID_MPEG_VIDEO_VPX_PROFILE in
drivers of Qualcomm's venus and Samsung's s5p-mfc.
Signed-off-by: Keiichi Watanabe <keiichiw@chromium.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The patch 'backlight: pwm_bl: compute brightness of LED linearly to
human eye' introduced a default brightness-levels table that is used
when brightness-levels is not available in the dts. So move
brightness-levels and default-brightness-level to be optional.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The num-interpolated-steps property specifies the number of
interpolated steps between each value of brightness-level table. This is
useful for high resolution PWMs to not have to list out every possible
value in the brightness-level array.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Two requests have come in for a backmerge,
and I've got some pull reqs on rc2, so this
just makes sense.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Intel Ice Lake has the same SMBus host controller than Intel Cannon
Lake. Add the PCI ID to the drivers list of supported devices.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[jarkko.nikula@linux.intel.com: Add entries to Documentation and Kconfig]
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Make list of supported chipsets a little bit shorter by consolidating
names that belong to the same family.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add another injector for an incomplete transfer. As mentioned in the
docs, this one is important to check bus recovery algorithms with it.
Otherwise random data may be sent to devices!
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Make the incomplete_transfer routine reusable, so we can add other test
cases with different patterns later. Prepare the docs for that, too.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
People have gone to all the effort of writing kernel-doc for these
functions; the least we can do is put them in the "Other functions"
part of the VFS documentation.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Update the binding to be able to configure the LED
sync to turn on.
The LM36922 has one output but can sync current to 2 LED
strings. The user may only use one sync so the other
syncs need to be disabled.
The LM36923 has 3 LED syncs.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
This patch adds the bindings document for LT3593 LED drivers.
The binding is kept consistent with other LED driver bindings in that it
stores all the LED-specific properties in its own subnode. As the hardware
only supports one channel, there can consequently only be one sub-node.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Add devicetree bindings for Rockchip cru which found on
Rockchip SoCs.
Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
The optional clock phandle to aclk (Audio PLL clock) is no longer needed
by the driver.
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Update the documentation to add support for the es7154 and
optional power supplies phandles.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
The ME FW version is constantly used by detection and update tools.
To improve the reliability and simplify these tools provide
a sysfs interface to access version of the platform ME firmware
in the following format:
<platform>:<major>.<minor>.<milestone>.<build>.
There can be up to three such blocks for different FW components.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current Wound-Wait mutex algorithm is actually not Wound-Wait but
Wait-Die. Implement also Wound-Wait as a per-ww-class choice. Wound-Wait
is, contrary to Wait-Die a preemptive algorithm and is known to generate
fewer backoffs. Testing reveals that this is true if the
number of simultaneous contending transactions is small.
As the number of simultaneous contending threads increases, Wait-Wound
becomes inferior to Wait-Die in terms of elapsed time.
Possibly due to the larger number of held locks of sleeping transactions.
Update documentation and callers.
Timings using git://people.freedesktop.org/~thomash/ww_mutex_test
tag patch-18-06-15
Each thread runs 100000 batches of lock / unlock 800 ww mutexes randomly
chosen out of 100000. Four core Intel x86_64:
Algorithm #threads Rollbacks time
Wound-Wait 4 ~100 ~17s.
Wait-Die 4 ~150000 ~19s.
Wound-Wait 16 ~360000 ~109s.
Wait-Die 16 ~450000 ~82s.
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-doc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Co-authored-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
When a resource group enters pseudo-locksetup mode it reflects that the
platform supports cache pseudo-locking and the resource group is unused,
ready to be used for a pseudo-locked region. Until it is set up as a
pseudo-locked region the resource group is "locked down" such that no new
tasks or cpus can be assigned to it. This is accomplished in a user visible
way by making the cpus, cpus_list, and tasks resctrl files inaccassible
(user cannot read from or write to these files).
When the resource group changes to pseudo-locked mode it represents a cache
pseudo-locked region. While not appropriate to make any changes to the cpus
assigned to this region it is useful to make it easy for the user to see
which cpus are associated with the pseudo-locked region.
Modify the permissions of the cpus/cpus_list file when the resource group
changes to pseudo-locked mode to support reading (not writing). The
information presented to the user when reading the file are the cpus
associated with the pseudo-locked region.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: vikas.shivappa@linux.intel.com
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/12756b7963b6abc1bffe8fb560b87b75da827bd1.1530421961.git.reinette.chatre@intel.com
Simple overlapping changes in stmmac driver.
Adjust skb_gro_flush_final_remcsum function signature to make GRO list
changes in net-next, as per Stephen Rothwell's example merge
resolution.
Signed-off-by: David S. Miller <davem@davemloft.net>
Add an optional parameter "start_sector" to allow the start of the
device to be offset by the specified number of 512-byte sectors. The
sectors below this offset are not used by the writecache device and are
left to be used for disk labels and/or userspace metadata (e.g. lvm).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Despite being mentioned at Documentation/trace/ftrace.rst as a
rst file, this file was still a text one, with several issues.
Convert it to ReST and add it to the trace index:
- Mark the document title as such;
- Identify and indent the literal blocks;
- Use the proper markups for table.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
