These documents are long and have various sections. Provide a good
toc nesting level.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Mauro's auto conversion broken these links, fix them.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
There are 4 RCU articles that are written on html format.
The way they are, they can't be part of the Linux Kernel
documentation body nor share the styles and pdf output.
So, convert them to ReST format.
This way, make htmldocs and make pdfdocs will produce a
documentation output that will be like the original ones, but
will be part of the Linux Kernel documentation body.
Part of the conversion was done with the help of pandoc, but
the result had some broken things that had to be manually
fixed.
Following are manual changes Mauro made when doing the automatic conversion:
Quoting from: https://lore.kernel.org/rcu/20190726154550.5eeae294@coco.lan/
> > At least the pandoc's version I used here has a bug: its conversion
> > from html to ReST on those files only start after a <body> tag - or
> > when the first quiz table starts. I only discovered that adding a
> > <body> at the beginning of the file solve this book at the last
> > conversions.
> >
> > So, for most html->ReST conversions, I manually converted the first
> > part of the document, basically stripping html paragraph tags and
> > by replacing highlights by the ReST syntax.
> >
> > Also, all the quiz tables seem to assume some javascript macro or
> > css style that would be hiding the answer part until the mouse moves
> > to it. Such macro/css was not there at the kernel tree. So, the quiz
> > answers have the same color as the background, making them invisible.
> > Even if we had such macro/css, this is not portable for pdf/LaTeX output
> > (and I'm not sure if this would work with ePub).
> >
> > So, I ended by manually doing the table conversion.
> >
> > Finally, I double-checked if the conversions ended ok, addressing any
> > issues that might have heppened.
> >
> > So, after both automatic conversion and manual fixes, I opened both the
> > html files produced by Sphinx and the original ones and compared them
> > line per line (except for the indexes, as Sphinx produces them
> > automatically), in order to see if all information from the original
> > files will be there on a format close to what we have on other ReST
> > files, fixing any pending issues if any.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This reverts docs from commit 355e9972da81e803bbb825b76106ae9b358caf8e.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Added Joel's SoB per Stephen Rothwell feedback. ]
[ paulmck: Joel approved via private email. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This reverts docs from commit d6b9cd7dc8e041ee83cb1362fce59a3cdb1f2709.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Added Joel's SoB per Stephen Rothwell feedback. ]
[ paulmck: Joel approved via private email. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that we have a vtime safe kcpustat accessor for CPUTIME_SYSTEM, use
it to start fixing frozen kcpustat values on nohz_full CPUs.
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-15-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that we have a vtime safe kcpustat accessor for CPUTIME_SYSTEM, use
it to start fixing frozen kcpustat values on nohz_full CPUs.
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-14-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that we have a vtime safe kcpustat accessor for CPUTIME_SYSTEM, use
it to start fixing frozen kcpustat values on nohz_full CPUs.
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-13-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Kcpustat is not correctly supported on nohz_full CPUs. The tick doesn't
fire and the cputime therefore doesn't move forward. The issue has shown
up after the vanishing of the remaining 1Hz which has made the stall
visible.
We are solving that with checking the task running on a CPU through RCU
and reading its vtime delta that we add to the raw kcpustat values.
We make sure that we fetch a coherent raw-kcpustat/vtime-delta couple
sequence while checking that the CPU referred by the target vtime is the
correct one, under the locked vtime seqcount.
Only CPUTIME_SYSTEM is handled here as a start because it's the trivial
case. User and guest time will require more preparation work to
correctly handle niceness.
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Link: https://lkml.kernel.org/r/20191025020303.19342-1-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
guest_enter() doesn't call context_tracking_enabled() before calling
context_tracking_enabled_this_cpu(). Therefore the guest code doesn't
benefit from the static key on the fast path.
Just make sure that context_tracking_enabled_*cpu() functions check
the static key by themselves to propagate the optimization.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-11-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This allows us to check if a remote CPU runs vtime accounting
(ie: is nohz_full). We'll need that to reliably support reading kcpustat
on nohz_full CPUs.
Also simplify a bit the condition in the local flavoured function while
at it.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-10-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Standardize the naming on top of the vtime_accounting_enabled_*() base.
Also make it clear we are checking the vtime state of the
*current* CPU with this function. We'll need to add an API to check that
state on remote CPUs as well, so we must disambiguate the naming.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-9-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This allows us to check if a remote CPU runs context tracking
(ie: is nohz_full). We'll need that to reliably support "nice"
accounting on kcpustat.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-8-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Standardize the naming on top of the context_tracking_enabled_*() base.
Also make it clear we are checking the context tracking state of the
*current* CPU with this function. We'll need to add an API to check that
state on remote CPUs as well, so we must disambiguate the naming.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-7-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove the superfluous "is" in the middle of the name. We want to
standardize the naming so that it can be expanded through suffixes:
context_tracking_enabled()
context_tracking_enabled_cpu()
context_tracking_enabled_this_cpu()
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-6-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This function is a leftover from old removal or rename. We can drop it.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-5-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Record guest as a VTIME state instead of guessing it from VTIME_SYS and
PF_VCPU. This is going to simplify the cputime read side especially as
its state machine is going to further expand in order to fully support
kcpustat on nohz_full.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-4-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Record idle as a VTIME state instead of guessing it from VTIME_SYS and
is_idle_task(). This is going to simplify the cputime read side
especially as its state machine is going to further expand in order to
fully support kcpustat on nohz_full.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-3-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In order to compute the kcpustat delta on a nohz CPU, we'll need to
fetch the task running on that target. Checking that its vtime
state snapshot actually refers to the relevant target involves recording
that CPU under the seqcount locked on task switch.
This is a step toward making kcpustat moving forward on full nohz CPUs.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The estimated utilization for a task:
util_est = max(util_avg, est.enqueue, est.ewma)
is defined based on:
- util_avg: the PELT defined utilization
- est.enqueued: the util_avg at the end of the last activation
- est.ewma: a exponential moving average on the est.enqueued samples
According to this definition, when a task suddenly changes its bandwidth
requirements from small to big, the EWMA will need to collect multiple
samples before converging up to track the new big utilization.
This slow convergence towards bigger utilization values is not
aligned to the default scheduler behavior, which is to optimize for
performance. Moreover, the est.ewma component fails to compensate for
temporarely utilization drops which spans just few est.enqueued samples.
To let util_est do a better job in the scenario depicted above, change
its definition by making util_est directly follow upward motion and
only decay the est.ewma on downward.
Signed-off-by: Patrick Bellasi <patrick.bellasi@matbug.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Douglas Raillard <douglas.raillard@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <qperret@google.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191023205630.14469-1-patrick.bellasi@matbug.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While the static key is correctly initialized as being disabled, it will
remain forever enabled once turned on. This means that if we start with an
asymmetric system and hotplug out enough CPUs to end up with an SMP system,
the static key will remain set - which is obviously wrong. We should detect
this and turn off things like misfit migration and capacity aware wakeups.
As Quentin pointed out, having separate root domains makes this slightly
trickier. We could have exclusive cpusets that create an SMP island - IOW,
the domains within this root domain will not see any asymmetry. This means
we can't just disable the key on domain destruction, we need to count how
many asymmetric root domains we have.
Consider the following example using Juno r0 which is 2+4 big.LITTLE, where
two identical cpusets are created: they both span both big and LITTLE CPUs:
asym0 asym1
[ ][ ]
L L B L L B
$ cgcreate -g cpuset:asym0
$ cgset -r cpuset.cpus=0,1,3 asym0
$ cgset -r cpuset.mems=0 asym0
$ cgset -r cpuset.cpu_exclusive=1 asym0
$ cgcreate -g cpuset:asym1
$ cgset -r cpuset.cpus=2,4,5 asym1
$ cgset -r cpuset.mems=0 asym1
$ cgset -r cpuset.cpu_exclusive=1 asym1
$ cgset -r cpuset.sched_load_balance=0 .
(the CPU numbering may look odd because on the Juno LITTLEs are CPUs 0,3-5
and bigs are CPUs 1-2)
If we make one of those SMP (IOW remove asymmetry) by e.g. hotplugging its
big core, we would end up with an SMP cpuset and an asymmetric cpuset - the
static key must remain set, because we still have one asymmetric root domain.
With the above example, this could be done with:
$ echo 0 > /sys/devices/system/cpu/cpu2/online
Which would result in:
asym0 asym1
[ ][ ]
L L B L L
When both SMP and asymmetric cpusets are present, all CPUs will observe
sched_asym_cpucapacity being set (it is system-wide), but not all CPUs
observe asymmetry in their sched domain hierarchy:
per_cpu(sd_asym_cpucapacity, <any CPU in asym0>) == <some SD at DIE level>
per_cpu(sd_asym_cpucapacity, <any CPU in asym1>) == NULL
Change the simple key enablement to an increment, and decrement the key
counter when destroying domains that cover asymmetric CPUs.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Dietmar.Eggemann@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hannes@cmpxchg.org
Cc: lizefan@huawei.com
Cc: morten.rasmussen@arm.com
Cc: qperret@google.com
Cc: tj@kernel.org
Cc: vincent.guittot@linaro.org
Fixes: df054e8445 ("sched/topology: Add static_key for asymmetric CPU capacity optimizations")
Link: https://lkml.kernel.org/r/20191023153745.19515-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Endpoints with a maxpacket length of 0 are probably useless. They
can't transfer any data, and it's not at all unlikely that a UDC will
crash or hang when trying to handle a non-zero-length usb_request for
such an endpoint. Indeed, dummy-hcd gets a divide error when trying
to calculate the remainder of a transfer length by the maxpacket
value, as discovered by the syzbot fuzzer.
Currently the gadget core does not check for endpoints having a
maxpacket value of 0. This patch adds a check to usb_ep_enable(),
preventing such endpoints from being used.
As far as I know, none of the gadget drivers in the kernel tries to
create an endpoint with maxpacket = 0, but until now there has been
nothing to prevent userspace programs under gadgetfs or configfs from
doing it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: syzbot+8ab8bf161038a8768553@syzkaller.appspotmail.com
CC: <stable@vger.kernel.org>
Acked-by: Felipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.1910281052370.1485-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PRCM_PWROFF_GATING_REG has CPU0 at bit 4 on A83T. So without this
patch, instead of gating the CPU0, the whole cluster was power gated,
when shutting down first CPU in the cluster.
Fixes: 6961275e72 ("ARM: sun8i: smp: Add support for A83T")
Signed-off-by: Ondrej Jirman <megous@megous.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Cc: stable@vger.kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>
The closing parenthesis of a multiline parameter list looks better
in the same line as the last parameter.
The comma that separates parameters should be at the end of the line.
Signed-off-by: Frank A. Cancio Bello <frank@generalsoftwareinc.com>
Link: https://lore.kernel.org/r/20191028165906.tv5zxjiqwjthygnq@linux-kernel-dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
checkpatch messaages:
CHECK:OPEN_ENDED_LINE: Lines should not end with a '('
CHECK:PARENTHESIS_ALIGNMENT: Alignment should match open parenthesis
Signed-off-by: Frank A. Cancio Bello <frank@generalsoftwareinc.com>
Link: https://lore.kernel.org/r/20191028161401.sjhp6qivm6huxpxm@linux-kernel-dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When killing hostapd, the interface is closed which deinitializes the
device, then change virtual interface is called.
This change checks if the device is initialized before sending the
interface change command to the device
Signed-off-by: Adham Abozaeid <adham.abozaeid@microchip.com>
Link: https://lore.kernel.org/r/20191028184019.31194-1-adham.abozaeid@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without enabling keep-power-in-suspend, we can't wake the device
up using WOL packet, and the log is flooded with these messages
on resume:
sunxi-mmc 1c10000.mmc: send stop command failed
sunxi-mmc 1c10000.mmc: data error, sending stop command
sunxi-mmc 1c10000.mmc: send stop command failed
sunxi-mmc 1c10000.mmc: data error, sending stop command
So to make the WiFi really a wakeup-source, we need to keep it powered
during suspend.
Fixes: 0e23372080 ("arm: dts: sun8i: Add the TBS A711 tablet devicetree")
Signed-off-by: Ondrej Jirman <megous@megous.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
The zero'ing of bits 16 and 18 is incorrect. Currently the code
is masking with the bitwise-and of BIT(16) & BIT(18) which is
0, so the updated value for val is always zero. Fix this by bitwise
and-ing value with the correct mask that will zero bits 16 and 18.
Addresses-Coverity: (" Suspicious &= or |= constant expression")
Fixes: b8eb71dcdd ("clk: sunxi-ng: Add A80 CCU")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
r375326 in Clang exposes an issue with operator precedence in
sunxi_div_clk_setup:
drivers/clk/sunxi/clk-sunxi.c:1083:30: warning: operator '?:' has lower
precedence than '|'; '|' will be evaluated first
[-Wbitwise-conditional-parentheses]
data->div[i].critical ?
~~~~~~~~~~~~~~~~~~~~~ ^
drivers/clk/sunxi/clk-sunxi.c:1083:30: note: place parentheses around
the '|' expression to silence this warning
data->div[i].critical ?
^
)
drivers/clk/sunxi/clk-sunxi.c:1083:30: note: place parentheses around
the '?:' expression to evaluate it first
data->div[i].critical ?
^
(
1 warning generated.
It appears that the intention was for ?: to be evaluated first so that
CLK_IS_CRITICAL could be added to clkflags if the critical boolean was
set; right now, | is being evaluated first. Add parentheses around the
?: block to have it be evaluated first.
Fixes: 9919d44ff2 ("clk: sunxi: Use CLK_IS_CRITICAL flag for critical clks")
Link: https://github.com/ClangBuiltLinux/linux/issues/745
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
There is nothing to say that the obj->base.size is actually a multiple
of the block_size.
v2: Use round_up() as block_size is a power-of-two
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028220325.9325-1-chris@chris-wilson.co.uk
Add a header with symbolic reset indices for Realtek RTD1295 SoC.
Naming was derived from reset-names in an OEM's Device Tree.
Acked-by: Rob Herring <robh@kernel.org>
[AF: Dropped RTD1295 specific binding definition, updated SPDX]
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Andreas Färber <afaerber@suse.de>
The ultravisor will do an integrity check of the kernel image but we
relocated it so the check will fail. Restore the original image by
relocating it back to the kernel virtual base address.
This works because during build vmlinux is linked with an expected
virtual runtime address of KERNELBASE.
Fixes: 6a9c930bd7 ("powerpc/prom_init: Add the ESM call to prom_init")
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Tested-by: Michael Anderson <andmike@linux.ibm.com>
[mpe: Add IS_ENABLED() to fix the CONFIG_RELOCATABLE=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190911163433.12822-1-bauerman@linux.ibm.com
Add the support for enabling optional regulator that may be used as VCC
source.
Signed-off-by: Mylène Josserand <mylene.josserand@bootlin.com>
Signed-off-by: Ondrej Jirman <megous@megous.com>
Reviewed-by: Rob Herring <robh@kernel.org> # bindings
Link: https://lore.kernel.org/r/20191029005806.3577376-2-megous@megous.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Switch the driver to the slotted variant of multitouch protocol (MT-B)
with in-kernel tracking of the contacts.
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The receiving buffer is allocated separately from the main driver
data structure, and is naturally DMA-safe, so mark it as such when
building I2C transfer message.
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The finger structure size is quite small and allocating it together with
the main driver structure will not increase likelyhood of allocation
failing, but reduces number of objects needing to be tracked by the
allocator and devm.
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
We should not be putting the chip into reset while interrupts are enabled
and ISR may be running. Fix this by installing a custom devm action and
powering off the device/resetting GPIO line from there. This ensures proper
ordering.
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
When I2C client is created with I2C_CLIENT_WAKE flag (which happens
either because we have "wakeup-source" device property or the flag
was passed in when creating an I2C client manually), I2C core will
take care of configuring interrupt as wakeup source on suspend.
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Do not unconditionally configure the touchscreen as wakeup source but
rather rely on I2C core to do that when requested (either via
"wakeup-source" device property, or when creating a client with
I2C_CLIENT_WAKE flag).
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Avoid complex 2-variable loop when parsing touchscreen data to make the
code clearer.
Acked-by: Martin Kepplinger <martink@posteo.de>
Tested-by: Matthias Fend <Matthias.Fend@wolfvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Add the watchdog node to the RTD129x Device Tree.
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
[AF: Moved from RTD1295 to new RTD129x]
Signed-off-by: Andreas Färber <afaerber@suse.de>
