Pull core locking updates from Ingo Molnar:
"The main changes in this cycle are:
- Another attempt at enabling cross-release lockdep dependency
tracking (automatically part of CONFIG_PROVE_LOCKING=y), this time
with better performance and fewer false positives. (Byungchul Park)
- Introduce lockdep_assert_irqs_enabled()/disabled() and convert
open-coded equivalents to lockdep variants. (Frederic Weisbecker)
- Add down_read_killable() and use it in the VFS's iterate_dir()
method. (Kirill Tkhai)
- Convert remaining uses of ACCESS_ONCE() to
READ_ONCE()/WRITE_ONCE(). Most of the conversion was Coccinelle
driven. (Mark Rutland, Paul E. McKenney)
- Get rid of lockless_dereference(), by strengthening Alpha atomics,
strengthening READ_ONCE() with smp_read_barrier_depends() and thus
being able to convert users of lockless_dereference() to
READ_ONCE(). (Will Deacon)
- Various micro-optimizations:
- better PV qspinlocks (Waiman Long),
- better x86 barriers (Michael S. Tsirkin)
- better x86 refcounts (Kees Cook)
- ... plus other fixes and enhancements. (Borislav Petkov, Juergen
Gross, Miguel Bernal Marin)"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
locking/x86: Use LOCK ADD for smp_mb() instead of MFENCE
rcu: Use lockdep to assert IRQs are disabled/enabled
netpoll: Use lockdep to assert IRQs are disabled/enabled
timers/posix-cpu-timers: Use lockdep to assert IRQs are disabled/enabled
sched/clock, sched/cputime: Use lockdep to assert IRQs are disabled/enabled
irq_work: Use lockdep to assert IRQs are disabled/enabled
irq/timings: Use lockdep to assert IRQs are disabled/enabled
perf/core: Use lockdep to assert IRQs are disabled/enabled
x86: Use lockdep to assert IRQs are disabled/enabled
smp/core: Use lockdep to assert IRQs are disabled/enabled
timers/hrtimer: Use lockdep to assert IRQs are disabled/enabled
timers/nohz: Use lockdep to assert IRQs are disabled/enabled
workqueue: Use lockdep to assert IRQs are disabled/enabled
irq/softirqs: Use lockdep to assert IRQs are disabled/enabled
locking/lockdep: Add IRQs disabled/enabled assertion APIs: lockdep_assert_irqs_enabled()/disabled()
locking/pvqspinlock: Implement hybrid PV queued/unfair locks
locking/rwlocks: Fix comments
x86/paravirt: Set up the virt_spin_lock_key after static keys get initialized
block, locking/lockdep: Assign a lock_class per gendisk used for wait_for_completion()
workqueue: Remove now redundant lock acquisitions wrt. workqueue flushes
...
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle are:
- Documentation updates
- RCU CPU stall-warning updates
- Torture-test updates
- Miscellaneous fixes
Size wise the biggest updates are to documentation. Excluding
documentation most of the code increase comes from a single commit
which expands debugging"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
srcu: Add parameters to SRCU docbook comments
doc: Rewrite confusing statement about memory barriers
memory-barriers.txt: Fix typo in pairing example
rcu/segcblist: Include rcupdate.h
rcu: Add extended-quiescent-state testing advice
rcu: Suppress lockdep false-positive ->boost_mtx complaints
rcu: Do not include rtmutex_common.h unconditionally
torture: Provide TMPDIR environment variable to specify tmpdir
rcutorture: Dump writer stack if stalled
rcutorture: Add interrupt-disable capability to stall-warning tests
rcu: Suppress RCU CPU stall warnings while dumping trace
rcu: Turn off tracing before dumping trace
rcu: Make RCU CPU stall warnings check for irq-disabled CPUs
sched,rcu: Make cond_resched() provide RCU quiescent state
sched: Make resched_cpu() unconditional
irq_work: Map irq_work_on_queue() to irq_work_on() in !SMP
rcu: Create call_rcu_tasks() kthread at boot time
rcu: Fix up pending cbs check in rcu_prepare_for_idle
memory-barriers: Rework multicopy-atomicity section
memory-barriers: Replace uses of "transitive"
...
Pull security subsystem integrity updates from James Morris:
"There is a mixture of bug fixes, code cleanup, preparatory code for
new functionality and new functionality.
Commit 26ddabfe96 ("evm: enable EVM when X509 certificate is
loaded") enabled EVM without loading a symmetric key, but was limited
to defining the x509 certificate pathname at build. Included in this
set of patches is the ability of enabling EVM, without loading the EVM
symmetric key, from userspace. New is the ability to prevent the
loading of an EVM symmetric key."
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
ima: Remove redundant conditional operator
ima: Fix bool initialization/comparison
ima: check signature enforcement against cmdline param instead of CONFIG
module: export module signature enforcement status
ima: fix hash algorithm initialization
EVM: Only complain about a missing HMAC key once
EVM: Allow userspace to signal an RSA key has been loaded
EVM: Include security.apparmor in EVM measurements
ima: call ima_file_free() prior to calling fasync
integrity: use kernel_read_file_from_path() to read x509 certs
ima: always measure and audit files in policy
ima: don't remove the securityfs policy file
vfs: fix mounting a filesystem with i_version
The (alleged) users of the module addresses are the same: kernel
profiling.
So just expose the same helper and format macros, and unify the logic.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This code goes back to the historical bitkeeper tree commit 3f7b0672086
("Module section offsets in /sys/module"), where Jonathan Corbet wanted
to show people how to debug loadable modules.
See
https://lwn.net/Articles/88052/
from June 2004.
To expose the required load address information, Jonathan added the
sections subdirectory for every module in /sys/modules, and made them
S_IRUGO - readable by everybody.
It was a more innocent time, plus those S_IRxxx macro names are a lot
more confusing than the octal numbers are, so maybe it wasn't even
intentional. But here we are, thirteen years later, and I'll just change
it to S_IRUSR instead.
Let's see if anybody even notices.
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge /proc/kallsyms pointer value restrictions.
Instead of using %pK, and making it about root access (at the wrong
time, no less), make the whole choice of whether to show the actual
pointer value be very explicit to the kallsyms code.
In particular, we can now default to not doing so, and yet avoid
annoying kernel profiling by actually looking at whether kernel
profiling is allowed or not (by default it is not).
This is all mostly preparation for the real "let's stop leaking kernel
addresses" work that Tobin Harding is working on.
Small steps.
* kallsyms-restrictions:
stop using '%pK' for /proc/kallsyms pointer values
- Prevent the schedutil cpufreq governor from using the
utilization of a wrong CPU in some cases which started to
happen after one of the recent changes in it (Chris Redpath).
- Blacklist Dell XPS13 9360 from using the Low Power S0 Idle _DSM
interface as that causes serious issue (related to NVMe) to
appear on one of these machines, even though the other Dells
XPS13 9360 in somewhat different HW configurations behave
correctly (Rafael Wysocki).
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Merge tag 'pm-final-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull final power management fixes from Rafael Wysocki:
"These fix a regression in the schedutil cpufreq governor introduced by
a recent change and blacklist Dell XPS13 9360 from using the Low Power
S0 Idle _DSM interface which triggers serious problems on one of these
machines.
Specifics:
- Prevent the schedutil cpufreq governor from using the utilization
of a wrong CPU in some cases which started to happen after one of
the recent changes in it (Chris Redpath).
- Blacklist Dell XPS13 9360 from using the Low Power S0 Idle _DSM
interface as that causes serious issue (related to NVMe) to appear
on one of these machines, even though the other Dells XPS13 9360 in
somewhat different HW configurations behave correctly (Rafael
Wysocki)"
* tag 'pm-final-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / PM: Blacklist Low Power S0 Idle _DSM for Dell XPS13 9360
cpufreq: schedutil: Examine the correct CPU when we update util
Not only is it annoying to have one single flag for all pointers, as if
that was a global choice and all kernel pointers are the same, but %pK
can't get the 'access' vs 'open' time check right anyway.
So make the /proc/kallsyms pointer value code use logic specific to that
particular file. We do continue to honor kptr_restrict, but the default
(which is unrestricted) is changed to instead take expected users into
account, and restrict access by default.
Right now the only actual expected user is kernel profiling, which has a
separate sysctl flag for kernel profile access. There may be others.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A static variable sig_enforce is used as status var to indicate the real
value of CONFIG_MODULE_SIG_FORCE, once this one is set the var will hold
true, but if the CONFIG is not set the status var will hold whatever
value is present in the module.sig_enforce kernel cmdline param: true
when =1 and false when =0 or not present.
Considering this cmdline param take place over the CONFIG value when
it's not set, other places in the kernel could misbehave since they
would have only the CONFIG_MODULE_SIG_FORCE value to rely on. Exporting
this status var allows the kernel to rely in the effective value of
module signature enforcement, being it from CONFIG value or cmdline
param.
Signed-off-by: Bruno E. O. Meneguele <brdeoliv@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Lockdep now has an integrated IRQs disabled/enabled sanity check. Just
use it instead of the ad-hoc RCU version.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-15-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-13-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-12-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-11-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-10-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-9-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-7-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-6-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1509980490-4285-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use lockdep to check that IRQs are enabled or disabled as expected. This
way the sanity check only shows overhead when concurrency correctness
debug code is enabled.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S . Miller <davem@davemloft.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1509980490-4285-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, all the lock waiters entering the slowpath will do one
lock stealing attempt to acquire the lock. That helps performance,
especially in VMs with over-committed vCPUs. However, the current
pvqspinlocks still don't perform as good as unfair locks in many cases.
On the other hands, unfair locks do have the problem of lock starvation
that pvqspinlocks don't have.
This patch combines the best attributes of an unfair lock and a
pvqspinlock into a hybrid lock with 2 modes - queued mode & unfair
mode. A lock waiter goes into the unfair mode when there are waiters
in the wait queue but the pending bit isn't set. Otherwise, it will
go into the queued mode waiting in the queue for its turn.
On a 2-socket 36-core E5-2699 v3 system (HT off), a kernel build
(make -j<n>) was done in a VM with unpinned vCPUs 3 times with the
best time selected and <n> is the number of vCPUs available. The build
times of the original pvqspinlock, hybrid pvqspinlock and unfair lock
with various number of vCPUs are as follows:
vCPUs pvqlock hybrid pvqlock unfair lock
----- ------- -------------- -----------
30 342.1s 329.1s 329.1s
36 314.1s 305.3s 307.3s
45 345.0s 302.1s 306.6s
54 365.4s 308.6s 307.8s
72 358.9s 293.6s 303.9s
108 343.0s 285.9s 304.2s
The hybrid pvqspinlock performs better or comparable to the unfair
lock.
By turning on QUEUED_LOCK_STAT, the table below showed the number
of lock acquisitions in unfair mode and queue mode after a kernel
build with various number of vCPUs.
vCPUs queued mode unfair mode
----- ----------- -----------
30 9,130,518 294,954
36 10,856,614 386,809
45 8,467,264 11,475,373
54 6,409,987 19,670,855
72 4,782,063 25,712,180
It can be seen that as the VM became more and more over-committed,
the ratio of locks acquired in unfair mode increases. This is all
done automatically to get the best overall performance as possible.
Using a kernel locking microbenchmark with number of locking
threads equals to the number of vCPUs available on the same machine,
the minimum, average and maximum (min/avg/max) numbers of locking
operations done per thread in a 5-second testing interval are shown
below:
vCPUs hybrid pvqlock unfair lock
----- -------------- -----------
36 822,135/881,063/950,363 75,570/313,496/ 690,465
54 542,435/581,664/625,937 35,460/204,280/ 457,172
72 397,500/428,177/499,299 17,933/150,679/ 708,001
108 257,898/288,150/340,871 3,085/181,176/1,257,109
It can be seen that the hybrid pvqspinlocks are more fair and
performant than the unfair locks in this test.
The table below shows the kernel build times on a smaller 2-socket
16-core 32-thread E5-2620 v4 system.
vCPUs pvqlock hybrid pvqlock unfair lock
----- ------- -------------- -----------
16 436.8s 433.4s 435.6s
36 366.2s 364.8s 364.5s
48 423.6s 376.3s 370.2s
64 433.1s 376.6s 376.8s
Again, the performance of the hybrid pvqspinlock was comparable to
that of the unfair lock.
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1510089486-3466-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull workqueue fix from Tejun Heo:
"Another fix for a really old bug.
It only affects drain_workqueue() which isn't used often and even then
triggers only during a pretty small race window, so it isn't too
surprising that it stayed hidden for so long.
The fix is straight-forward and low-risk. Kudos to Li Bin for
reporting and fixing the bug"
* 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Fix NULL pointer dereference
Pull perf fixes from Ingo Molnar:
"Various fixes:
- synchronize kernel and tooling headers
- cgroup support fix
- two tooling fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/headers: Synchronize kernel ABI headers
perf/cgroup: Fix perf cgroup hierarchy support
perf tools: Unwind properly location after REJECT
perf symbols: Fix memory corruption because of zero length symbols
After commit 674e75411f (sched: cpufreq: Allow remote cpufreq
callbacks) we stopped to always read the utilization for the CPU we
are running the governor on, and instead we read it for the CPU
which we've been told has updated utilization. This is stored in
sugov_cpu->cpu.
The value is set in sugov_register() but we clear it in sugov_start()
which leads to always looking at the utilization of CPU0 instead of
the correct one.
Fix this by consolidating the initialization code into sugov_start().
Fixes: 674e75411f (sched: cpufreq: Allow remote cpufreq callbacks)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Reviewed-by: Patrick Bellasi <patrick.bellasi@arm.com>
Reviewed-by: Brendan Jackman <brendan.jackman@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull initial SPDX identifiers from Greg KH:
"License cleanup: add SPDX license identifiers to some files
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the
'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally
binding shorthand, which can be used instead of the full boiler plate
text.
This patch is based on work done by Thomas Gleixner and Kate Stewart
and Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset
of the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to
license had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied
to a file was done in a spreadsheet of side by side results from of
the output of two independent scanners (ScanCode & Windriver)
producing SPDX tag:value files created by Philippe Ombredanne.
Philippe prepared the base worksheet, and did an initial spot review
of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537
files assessed. Kate Stewart did a file by file comparison of the
scanner results in the spreadsheet to determine which SPDX license
identifier(s) to be applied to the file. She confirmed any
determination that was not immediately clear with lawyers working with
the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained
>5 lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that
was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that
became the concluded license(s).
- when there was disagreement between the two scanners (one detected
a license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply
(and which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases,
confirmation by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.
The Windriver scanner is based on an older version of FOSSology in
part, so they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot
checks in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect
the correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial
patch version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch
license was not GPL-2.0 WITH Linux-syscall-note to ensure that the
applied SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'spdx_identifiers-4.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
License cleanup: add SPDX license identifier to uapi header files with a license
License cleanup: add SPDX license identifier to uapi header files with no license
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
In commit 30d6e0a419 ("futex: Remove duplicated code and fix undefined
behaviour"), I let FUTEX_WAKE_OP to fail on invalid op. Namely when op
should be considered as shift and the shift is out of range (< 0 or > 31).
But strace's test suite does this madness:
futex(0x7fabd78bcffc, 0x5, 0xfacefeed, 0xb, 0x7fabd78bcffc, 0xa0caffee);
futex(0x7fabd78bcffc, 0x5, 0xfacefeed, 0xb, 0x7fabd78bcffc, 0xbadfaced);
futex(0x7fabd78bcffc, 0x5, 0xfacefeed, 0xb, 0x7fabd78bcffc, 0xffffffff);
When I pick the first 0xa0caffee, it decodes as:
0x80000000 & 0xa0caffee: oparg is shift
0x70000000 & 0xa0caffee: op is FUTEX_OP_OR
0x0f000000 & 0xa0caffee: cmp is FUTEX_OP_CMP_EQ
0x00fff000 & 0xa0caffee: oparg is sign-extended 0xcaf = -849
0x00000fff & 0xa0caffee: cmparg is sign-extended 0xfee = -18
That means the op tries to do this:
(futex |= (1 << (-849))) == -18
which is completely bogus. The new check of op in the code is:
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) {
if (oparg < 0 || oparg > 31)
return -EINVAL;
oparg = 1 << oparg;
}
which results obviously in the "Invalid argument" errno:
FAIL: futex
===========
futex(0x7fabd78bcffc, 0x5, 0xfacefeed, 0xb, 0x7fabd78bcffc, 0xa0caffee) = -1: Invalid argument
futex.test: failed test: ../futex failed with code 1
So let us soften the failure to print only a (ratelimited) message, crop
the value and continue as if it were right. When userspace keeps up, we
can switch this to return -EINVAL again.
[v2] Do not return 0 immediatelly, proceed with the cropped value.
Fixes: 30d6e0a419 ("futex: Remove duplicated code and fix undefined behaviour")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull signal bugfix from Eric Biederman:
"When making the generic support for SIGEMT conditional on the presence
of SIGEMT I made a typo that causes it to fail to activate. It was
noticed comparatively quickly but the bug report just made it to me
today"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
signal: Fix name of SIGEMT in #if defined() check
Commit cc731525f2 ("signal: Remove kernel interal si_code magic")
added a check for SIGMET and NSIGEMT being defined. That SIGMET should
in fact be SIGEMT, with SIGEMT being defined in
arch/{alpha,mips,sparc}/include/uapi/asm/signal.h
This was actually pointed out by BenHutchings in a lwn.net comment
here https://lwn.net/Comments/734608/
Fixes: cc731525f2 ("signal: Remove kernel interal si_code magic")
Signed-off-by: Andrew Clayton <andrew@digital-domain.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Guenter reported:
There is still a problem. When running
echo 6 > /proc/sys/kernel/watchdog_thresh
echo 5 > /proc/sys/kernel/watchdog_thresh
repeatedly, the message
NMI watchdog: Enabled. Permanently consumes one hw-PMU counter.
stops after a while (after ~10-30 iterations, with fluctuations).
Maybe watchdog_cpus needs to be atomic ?
That's correct as this again is affected by the asynchronous nature of the
smpboot thread unpark mechanism.
CPU 0 CPU1 CPU2
write(watchdog_thresh, 6)
stop()
park()
update()
start()
unpark()
thread->unpark()
cnt++;
write(watchdog_thresh, 5) thread->unpark()
stop()
park() thread->park()
cnt--; cnt++;
update()
start()
unpark()
That's not a functional problem, it just affects the informational message.
Convert watchdog_cpus to atomic_t to prevent the problem
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20171101181126.j727fqjmdthjz4xk@redhat.com
Guenter reported a crash in the watchdog/perf code, which is caused by
cleanup() and enable() running concurrently. The reason for this is:
The watchdog functions are serialized via the watchdog_mutex and cpu
hotplug locking, but the enable of the perf based watchdog happens in
context of the unpark callback of the smpboot thread. But that unpark
function is not synchronous inside the locking. The unparking of the thread
just wakes it up and leaves so there is no guarantee when the thread is
executing.
If it starts running _before_ the cleanup happened then it will create a
event and overwrite the dead event pointer. The new event is then cleaned
up because the event is marked dead.
lock(watchdog_mutex);
lockup_detector_reconfigure();
cpus_read_lock();
stop();
park()
update();
start();
unpark()
cpus_read_unlock(); thread runs()
overwrite dead event ptr
cleanup();
free new event, which is active inside perf....
unlock(watchdog_mutex);
The park side is safe as that actually waits for the thread to reach
parked state.
Commit a33d44843d removed the protection against this kind of scenario
under the stupid assumption that the hotplug serialization and the
watchdog_mutex cover everything.
Bring it back.
Reverts: a33d44843d ("watchdog/hardlockup/perf: Simplify deferred event destroy")
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Feels-stupid Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Don Zickus <dzickus@redhat.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1710312145190.1942@nanos
Dmitry (through syzbot) reported being able to trigger the WARN in
get_pi_state() and a use-after-free on:
raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
Both are due to this race:
exit_pi_state_list() put_pi_state()
lock(&curr->pi_lock)
while() {
pi_state = list_first_entry(head);
hb = hash_futex(&pi_state->key);
unlock(&curr->pi_lock);
dec_and_test(&pi_state->refcount);
lock(&hb->lock)
lock(&pi_state->pi_mutex.wait_lock) // uaf if pi_state free'd
lock(&curr->pi_lock);
....
unlock(&curr->pi_lock);
get_pi_state(); // WARN; refcount==0
The problem is we take the reference count too late, and don't allow it
being 0. Fix it by using inc_not_zero() and simply retrying the loop
when we fail to get a refcount. In that case put_pi_state() should
remove the entry from the list.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Gratian Crisan <gratian.crisan@ni.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dvhart@infradead.org
Cc: syzbot <bot+2af19c9e1ffe4d4ee1d16c56ae7580feaee75765@syzkaller.appspotmail.com>
Cc: syzkaller-bugs@googlegroups.com
Cc: <stable@vger.kernel.org>
Fixes: c74aef2d06 ("futex: Fix pi_state->owner serialization")
Link: http://lkml.kernel.org/r/20171031101853.xpfh72y643kdfhjs@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that SK_REDIRECT is no longer a valid return code. Remove it
from the UAPI completely. Then do a namespace remapping internal
to sockmap so SK_REDIRECT is no longer externally visible.
Patchs primary change is to do a namechange from SK_REDIRECT to
__SK_REDIRECT
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When queue_work() is used in irq (not in task context), there is
a potential case that trigger NULL pointer dereference.
----------------------------------------------------------------
worker_thread()
|-spin_lock_irq()
|-process_one_work()
|-worker->current_pwq = pwq
|-spin_unlock_irq()
|-worker->current_func(work)
|-spin_lock_irq()
|-worker->current_pwq = NULL
|-spin_unlock_irq()
//interrupt here
|-irq_handler
|-__queue_work()
//assuming that the wq is draining
|-is_chained_work(wq)
|-current_wq_worker()
//Here, 'current' is the interrupted worker!
|-current->current_pwq is NULL here!
|-schedule()
----------------------------------------------------------------
Avoid it by checking for task context in current_wq_worker(), and
if not in task context, we shouldn't use the 'current' to check the
condition.
Reported-by: Xiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: Li Bin <huawei.libin@huawei.com>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 8d03ecfe47 ("workqueue: reimplement is_chained_work() using current_wq_worker()")
Cc: stable@vger.kernel.org # v3.9+
The following commit:
864c2357ca ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups")
made list_update_cgroup_event() skip setting cpuctx->cgrp if no cgroup event
targets %current's cgroup.
This breaks perf_event's hierarchical support because events which target one
of the ancestors get ignored.
Fix it by using cgroup_is_descendant() test instead of equality.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: stable@vger.kernel.org # v4.9+
Fixes: 864c2357ca ("perf/core: Do not set cpuctx->cgrp for unscheduled cgroups")
Link: http://lkml.kernel.org/r/20171028164237.GA972780@devbig577.frc2.facebook.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull networking fixes from David Miller:
1) Fix route leak in xfrm_bundle_create().
2) In mac80211, validate user rate mask before configuring it. From
Johannes Berg.
3) Properly enforce memory limits in fair queueing code, from Toke
Hoiland-Jorgensen.
4) Fix lockdep splat in inet_csk_route_req(), from Eric Dumazet.
5) Fix TSO header allocation and management in mvpp2 driver, from Yan
Markman.
6) Don't take socket lock in BH handler in strparser code, from Tom
Herbert.
7) Don't show sockets from other namespaces in AF_UNIX code, from
Andrei Vagin.
8) Fix double free in error path of tap_open(), from Girish Moodalbail.
9) Fix TX map failure path in igb and ixgbe, from Jean-Philippe Brucker
and Alexander Duyck.
10) Fix DCB mode programming in stmmac driver, from Jose Abreu.
11) Fix err_count handling in various tunnels (ipip, ip6_gre). From Xin
Long.
12) Properly align SKB head before building SKB in tuntap, from Jason
Wang.
13) Avoid matching qdiscs with a zero handle during lookups, from Cong
Wang.
14) Fix various endianness bugs in sctp, from Xin Long.
15) Fix tc filter callback races and add selftests which trigger the
problem, from Cong Wang.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (73 commits)
selftests: Introduce a new test case to tc testsuite
selftests: Introduce a new script to generate tc batch file
net_sched: fix call_rcu() race on act_sample module removal
net_sched: add rtnl assertion to tcf_exts_destroy()
net_sched: use tcf_queue_work() in tcindex filter
net_sched: use tcf_queue_work() in rsvp filter
net_sched: use tcf_queue_work() in route filter
net_sched: use tcf_queue_work() in u32 filter
net_sched: use tcf_queue_work() in matchall filter
net_sched: use tcf_queue_work() in fw filter
net_sched: use tcf_queue_work() in flower filter
net_sched: use tcf_queue_work() in flow filter
net_sched: use tcf_queue_work() in cgroup filter
net_sched: use tcf_queue_work() in bpf filter
net_sched: use tcf_queue_work() in basic filter
net_sched: introduce a workqueue for RCU callbacks of tc filter
sctp: fix some type cast warnings introduced since very beginning
sctp: fix a type cast warnings that causes a_rwnd gets the wrong value
sctp: fix some type cast warnings introduced by transport rhashtable
sctp: fix some type cast warnings introduced by stream reconf
...
Recent additions to support multiple programs in cgroups impose
a strict requirement, "all yes is yes, any no is no". To enforce
this the infrastructure requires the 'no' return code, SK_DROP in
this case, to be 0.
To apply these rules to SK_SKB program types the sk_actions return
codes need to be adjusted.
This fix adds SK_PASS and makes 'SK_DROP = 0'. Finally, remove
SK_ABORTED to remove any chance that the API may allow aborted
program flows to be passed up the stack. This would be incorrect
behavior and allow programs to break existing policies.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
SK_SKB program types use bpf_compute_data to store the end of the
packet data. However, bpf_compute_data assumes the cb is stored in the
qdisc layer format. But, for SK_SKB this is the wrong layer of the
stack for this type.
It happens to work (sort of!) because in most cases nothing happens
to be overwritten today. This is very fragile and error prone.
Fortunately, we have another hole in tcp_skb_cb we can use so lets
put the data_end value there.
Note, SK_SKB program types do not use data_meta, they are failed by
sk_skb_is_valid_access().
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johan Hovold reported a heavy performance regression caused by lockdep
cross-release:
> Boot time (from "Linux version" to login prompt) had in fact doubled
> since 4.13 where it took 17 seconds (with my current config) compared to
> the 35 seconds I now see with 4.14-rc4.
>
> I quick bisect pointed to lockdep and specifically the following commit:
>
> 28a903f63e ("locking/lockdep: Handle non(or multi)-acquisition
> of a crosslock")
>
> which I've verified is the commit which doubled the boot time (compared
> to 28a903f63ec0^) (added by lockdep crossrelease series [1]).
Currently cross-release performs unwind on every acquisition, but that
is very expensive.
This patch makes unwind optional and disables it by default and only
records acquire_ip.
Full stack traces are sometimes required for full analysis, in which
case a boot paramter, crossrelease_fullstack, can be specified.
On my qemu Ubuntu machine (x86_64, 4 cores, 512M), the regression was
fixed. We measure boot times with 'perf stat --null --repeat 10 $QEMU',
where $QEMU launches a kernel with init=/bin/true:
1. No lockdep enabled:
Performance counter stats for 'qemu_booting_time.sh bzImage' (10 runs):
2.756558155 seconds time elapsed ( +- 0.09% )
2. Lockdep enabled:
Performance counter stats for 'qemu_booting_time.sh bzImage' (10 runs):
2.968710420 seconds time elapsed ( +- 0.12% )
3. Lockdep enabled + cross-release enabled:
Performance counter stats for 'qemu_booting_time.sh bzImage' (10 runs):
3.153839636 seconds time elapsed ( +- 0.31% )
4. Lockdep enabled + cross-release enabled + this patch applied:
Performance counter stats for 'qemu_booting_time.sh bzImage' (10 runs):
2.963669551 seconds time elapsed ( +- 0.11% )
I.e. lockdep cross-release performance is now indistinguishable from
vanilla lockdep.
Bisected-by: Johan Hovold <johan@kernel.org>
Analyzed-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: amir73il@gmail.com
Cc: axboe@kernel.dk
Cc: darrick.wong@oracle.com
Cc: david@fromorbit.com
Cc: hch@infradead.org
Cc: idryomov@gmail.com
Cc: johannes.berg@intel.com
Cc: kernel-team@lge.com
Cc: linux-block@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-xfs@vger.kernel.org
Cc: oleg@redhat.com
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/1508921765-15396-5-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't currently harmful.
However, for some features it is necessary to instrument reads and
writes separately, which is not possible with ACCESS_ONCE(). This
distinction is critical to correct operation.
It's possible to transform the bulk of kernel code using the Coccinelle
script below. However, this doesn't handle comments, leaving references
to ACCESS_ONCE() instances which have been removed. As a preparatory
step, this patch converts the workqueue code and comments to use
{READ,WRITE}_ONCE() consistently.
----
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-12-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a prospective writer takes the qrwlock locking slowpath due to the
lock being held, it attempts to cmpxchg the wmode field from 0 to
_QW_WAITING so that concurrent lockers also take the slowpath and queue
on the spinlock accordingly, allowing the lockers to drain.
Unfortunately, this isn't fair, because a fastpath writer that comes in
after the lock is made available but before the _QW_WAITING flag is set
can effectively jump the queue. If there is a steady stream of prospective
writers, then the waiter will be held off indefinitely.
This patch restores fairness by separating _QW_WAITING and _QW_LOCKED
into two distinct fields: _QW_LOCKED continues to occupy the bottom byte
of the lockword so that it can be cleared unconditionally when unlocking,
but _QW_WAITING now occupies what used to be the bottom bit of the reader
count. This then forces the slow-path for concurrent lockers.
Tested-by: Waiman Long <longman@redhat.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Adam Wallis <awallis@codeaurora.org>
Tested-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Jeremy.Linton@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1507810851-306-6-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The qrwlock slowpaths involve spinning when either a prospective reader
is waiting for a concurrent writer to drain, or a prospective writer is
waiting for concurrent readers to drain. In both of these situations,
atomic_cond_read_acquire() can be used to avoid busy-waiting and make use
of any backoff functionality provided by the architecture.
This patch replaces the open-code loops and rspin_until_writer_unlock()
implementation with atomic_cond_read_acquire(). The write mode transition
zero to _QW_WAITING is left alone, since (a) this doesn't need acquire
semantics and (b) should be fast.
Tested-by: Waiman Long <longman@redhat.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Adam Wallis <awallis@codeaurora.org>
Tested-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Jeremy.Linton@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1507810851-306-4-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
