Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull workqueue updates from Tejun Heo:
"Only three commits, of which two are trivial.
The non-trivial chagne is Thomas's patch to switch workqueue from
sched RCU to regular one. The use of sched RCU is mostly historic and
doesn't really buy us anything noticeable"
* 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Use normal rcu
kernel/workqueue: Document wq_worker_last_func() argument
kernel/workqueue: Use __printf markup to silence compiler in function 'alloc_workqueue'
Pull printk updates from Petr Mladek:
- Allow state reset of printk_once() calls.
- Prevent crashes when dereferencing invalid pointers in vsprintf().
Only the first byte is checked for simplicity.
- Make vsprintf warnings consistent and inlined.
- Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
modifiers.
- Some clean up of vsprintf and test_printf code.
* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
lib/vsprintf: Make function pointer_string static
vsprintf: Limit the length of inlined error messages
vsprintf: Avoid confusion between invalid address and value
vsprintf: Prevent crash when dereferencing invalid pointers
vsprintf: Consolidate handling of unknown pointer specifiers
vsprintf: Factor out %pO handler as kobject_string()
vsprintf: Factor out %pV handler as va_format()
vsprintf: Factor out %p[iI] handler as ip_addr_string()
vsprintf: Do not check address of well-known strings
vsprintf: Consistent %pK handling for kptr_restrict == 0
vsprintf: Shuffle restricted_pointer()
printk: Tie printk_once / printk_deferred_once into .data.once for reset
treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
lib/test_printf: Switch to bitmap_zalloc()
The worker accounting for CPU bound workers is plugged into the core
scheduler code and the wakeup code. This is not a hard requirement and
can be avoided by keeping track of the state in the workqueue code
itself.
Keep track of the sleeping state in the worker itself and call the
notifier before entering the core scheduler. There might be false
positives when the task is woken between that call and actually
scheduling, but that's not really different from scheduling and being
woken immediately after switching away. When nr_running is updated when
the task is retunrning from schedule() then it is later compared when it
is done from ttwu().
[ bigeasy: preempt_disable() around wq_worker_sleeping() by Daniel Bristot de Oliveira ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/ad2b29b5715f970bffc1a7026cabd6ff0b24076a.1532952814.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There is no need for sched_rcu. The undocumented reason why sched_rcu
is used is to avoid a few explicit rcu_read_lock()/unlock() pairs by
the fact that sched_rcu reader side critical sections are also protected
by preempt or irq disabled regions.
Replace rcu_read_lock_sched with rcu_read_lock and acquire the RCU lock
where it is not yet explicit acquired. Replace local_irq_disable() with
rcu_read_lock(). Update asserts.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: mangle changelog a little]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
This patch avoids that the following warning is reported when building
with W=1:
kernel/workqueue.c:938: warning: Function parameter or member 'task' not described in 'wq_worker_last_func'
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Silence warnings (triggered at W=1) by adding relevant __printf attributes.
kernel/workqueue.c:4249:2: warning: function 'alloc_workqueue' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull locking fixes from Thomas Gleixner:
"A few fixes for lockdep:
- initialize lockdep internal RCU head after initializing RCU
- prevent use after free in a alloc_workqueue() error handling path
- plug a memory leak in the workqueue core which fails to free a
dynamically allocated lock name.
- make Clang happy"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
workqueue, lockdep: Fix a memory leak in wq->lock_name
workqueue, lockdep: Fix an alloc_workqueue() error path
locking/lockdep: Only call init_rcu_head() after RCU has been initialized
locking/lockdep: Avoid a Clang warning
Merge more updates from Andrew Morton:
- some of the rest of MM
- various misc things
- dynamic-debug updates
- checkpatch
- some epoll speedups
- autofs
- rapidio
- lib/, lib/lzo/ updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (83 commits)
samples/mic/mpssd/mpssd.h: remove duplicate header
kernel/fork.c: remove duplicated include
include/linux/relay.h: fix percpu annotation in struct rchan
arch/nios2/mm/fault.c: remove duplicate include
unicore32: stop printing the virtual memory layout
MAINTAINERS: fix GTA02 entry and mark as orphan
mm: create the new vm_fault_t type
arm, s390, unicore32: remove oneliner wrappers for memblock_alloc()
arch: simplify several early memory allocations
openrisc: simplify pte_alloc_one_kernel()
sh: prefer memblock APIs returning virtual address
microblaze: prefer memblock API returning virtual address
powerpc: prefer memblock APIs returning virtual address
lib/lzo: separate lzo-rle from lzo
lib/lzo: implement run-length encoding
lib/lzo: fast 8-byte copy on arm64
lib/lzo: 64-bit CTZ on arm64
lib/lzo: tidy-up ifdefs
ipc/sem.c: replace kvmalloc/memset with kvzalloc and use struct_size
ipc: annotate implicit fall through
...
Pull workqueue updates from Tejun Heo:
"All trivial. Two comment updates and one more initialization sanity
check in flush_work()"
* 'for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Fix spelling in source code comments
workqueue: fix typo in comment
workqueue: Try to catch flush_work() without INIT_WORK().
Pull driver core updates from Greg KH:
"Here is the big driver core patchset for 5.1-rc1
More patches than "normal" here this merge window, due to some work in
the driver core by Alexander Duyck to rework the async probe
functionality to work better for a number of devices, and independant
work from Rafael for the device link functionality to make it work
"correctly".
Also in here is:
- lots of BUS_ATTR() removals, the macro is about to go away
- firmware test fixups
- ihex fixups and simplification
- component additions (also includes i915 patches)
- lots of minor coding style fixups and cleanups.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (65 commits)
driver core: platform: remove misleading err_alloc label
platform: set of_node in platform_device_register_full()
firmware: hardcode the debug message for -ENOENT
driver core: Add missing description of new struct device_link field
driver core: Fix PM-runtime for links added during consumer probe
drivers/component: kerneldoc polish
async: Add cmdline option to specify drivers to be async probed
driver core: Fix possible supplier PM-usage counter imbalance
PM-runtime: Fix __pm_runtime_set_status() race with runtime resume
driver: platform: Support parsing GpioInt 0 in platform_get_irq()
selftests: firmware: fix verify_reqs() return value
Revert "selftests: firmware: remove use of non-standard diff -Z option"
Revert "selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config"
device: Fix comment for driver_data in struct device
kernfs: Allocating memory for kernfs_iattrs with kmem_cache.
sysfs: remove unused include of kernfs-internal.h
driver core: Postpone DMA tear-down until after devres release
driver core: Document limitation related to DL_FLAG_RPM_ACTIVE
PM-runtime: Take suppliers into account in __pm_runtime_set_status()
device.h: Add __cold to dev_<level> logging functions
...
The following commit:
87915adc3f ("workqueue: re-add lockdep dependencies for flushing")
improved deadlock checking in the workqueue implementation. Unfortunately
that patch also introduced a few false positive lockdep complaints.
This patch suppresses these false positives by allocating the workqueue mutex
lockdep key dynamically.
An example of a false positive lockdep complaint suppressed by this patch
can be found below. The root cause of the lockdep complaint shown below
is that the direct I/O code can call alloc_workqueue() from inside a work
item created by another alloc_workqueue() call and that both workqueues
share the same lockdep key. This patch avoids that that lockdep complaint
is triggered by allocating the work queue lockdep keys dynamically.
In other words, this patch guarantees that a unique lockdep key is
associated with each work queue mutex.
======================================================
WARNING: possible circular locking dependency detected
4.19.0-dbg+ #1 Not tainted
fio/4129 is trying to acquire lock:
00000000a01cfe1a ((wq_completion)"dio/%s"sb->s_id){+.+.}, at: flush_workqueue+0xd0/0x970
but task is already holding lock:
00000000a0acecf9 (&sb->s_type->i_mutex_key#14){+.+.}, at: ext4_file_write_iter+0x154/0x710
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&sb->s_type->i_mutex_key#14){+.+.}:
down_write+0x3d/0x80
__generic_file_fsync+0x77/0xf0
ext4_sync_file+0x3c9/0x780
vfs_fsync_range+0x66/0x100
dio_complete+0x2f5/0x360
dio_aio_complete_work+0x1c/0x20
process_one_work+0x481/0x9f0
worker_thread+0x63/0x5a0
kthread+0x1cf/0x1f0
ret_from_fork+0x24/0x30
-> #1 ((work_completion)(&dio->complete_work)){+.+.}:
process_one_work+0x447/0x9f0
worker_thread+0x63/0x5a0
kthread+0x1cf/0x1f0
ret_from_fork+0x24/0x30
-> #0 ((wq_completion)"dio/%s"sb->s_id){+.+.}:
lock_acquire+0xc5/0x200
flush_workqueue+0xf3/0x970
drain_workqueue+0xec/0x220
destroy_workqueue+0x23/0x350
sb_init_dio_done_wq+0x6a/0x80
do_blockdev_direct_IO+0x1f33/0x4be0
__blockdev_direct_IO+0x79/0x86
ext4_direct_IO+0x5df/0xbb0
generic_file_direct_write+0x119/0x220
__generic_file_write_iter+0x131/0x2d0
ext4_file_write_iter+0x3fa/0x710
aio_write+0x235/0x330
io_submit_one+0x510/0xeb0
__x64_sys_io_submit+0x122/0x340
do_syscall_64+0x71/0x220
entry_SYSCALL_64_after_hwframe+0x49/0xbe
other info that might help us debug this:
Chain exists of:
(wq_completion)"dio/%s"sb->s_id --> (work_completion)(&dio->complete_work) --> &sb->s_type->i_mutex_key#14
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sb->s_type->i_mutex_key#14);
lock((work_completion)(&dio->complete_work));
lock(&sb->s_type->i_mutex_key#14);
lock((wq_completion)"dio/%s"sb->s_id);
*** DEADLOCK ***
1 lock held by fio/4129:
#0: 00000000a0acecf9 (&sb->s_type->i_mutex_key#14){+.+.}, at: ext4_file_write_iter+0x154/0x710
stack backtrace:
CPU: 3 PID: 4129 Comm: fio Not tainted 4.19.0-dbg+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
dump_stack+0x86/0xc5
print_circular_bug.isra.32+0x20a/0x218
__lock_acquire+0x1c68/0x1cf0
lock_acquire+0xc5/0x200
flush_workqueue+0xf3/0x970
drain_workqueue+0xec/0x220
destroy_workqueue+0x23/0x350
sb_init_dio_done_wq+0x6a/0x80
do_blockdev_direct_IO+0x1f33/0x4be0
__blockdev_direct_IO+0x79/0x86
ext4_direct_IO+0x5df/0xbb0
generic_file_direct_write+0x119/0x220
__generic_file_write_iter+0x131/0x2d0
ext4_file_write_iter+0x3fa/0x710
aio_write+0x235/0x330
io_submit_one+0x510/0xeb0
__x64_sys_io_submit+0x122/0x340
do_syscall_64+0x71/0x220
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Berg <johannes.berg@intel.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>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20190214230058.196511-20-bvanassche@acm.org
[ Reworked the changelog a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
psi has provisions to shut off the periodic aggregation worker when
there is a period of no task activity - and thus no data that needs
aggregating. However, while developing psi monitoring, Suren noticed
that the aggregation clock currently won't stay shut off for good.
Debugging this revealed a flaw in the idle design: an aggregation run
will see no task activity and decide to go to sleep; shortly thereafter,
the kworker thread that executed the aggregation will go idle and cause
a scheduling change, during which the psi callback will kick the
!pending worker again. This will ping-pong forever, and is equivalent
to having no shut-off logic at all (but with more code!)
Fix this by exempting aggregation workers from psi's clock waking logic
when the state change is them going to sleep. To do this, tag workers
with the last work function they executed, and if in psi we see a worker
going to sleep after aggregating psi data, we will not reschedule the
aggregation work item.
What if the worker is also executing other items before or after?
Any psi state times that were incurred by work items preceding the
aggregation work will have been collected from the per-cpu buckets
during the aggregation itself. If there are work items following the
aggregation work, the worker's last_func tag will be overwritten and the
aggregator will be kept alive to process this genuine new activity.
If the aggregation work is the last thing the worker does, and we decide
to go idle, the brief period of non-idle time incurred between the
aggregation run and the kworker's dequeue will be stranded in the
per-cpu buckets until the clock is woken by later activity. But that
should not be a problem. The buckets can hold 4s worth of time, and
future activity will wake the clock with a 2s delay, giving us 2s worth
of data we can leave behind when disabling aggregation. If it takes a
worker more than two seconds to go idle after it finishes its last work
item, we likely have bigger problems in the system, and won't notice one
sample that was averaged with a bogus per-CPU weight.
Link: http://lkml.kernel.org/r/20190116193501.1910-1-hannes@cmpxchg.org
Fixes: eb414681d5 ("psi: pressure stall information for CPU, memory, and IO")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide a new function, queue_work_node, which is meant to schedule work on
a "random" CPU of the requested NUMA node. The main motivation for this is
to help assist asynchronous init to better improve boot times for devices
that are local to a specific node.
For now we just default to the first CPU that is in the intersection of the
cpumask of the node and the online cpumask. The only exception is if the
CPU is local to the node we will just use the current CPU. This should work
for our purposes as we are currently only using this for unbound work so
the CPU will be translated to a node anyway instead of being directly used.
As we are only using the first CPU to represent the NUMA node for now I am
limiting the scope of the function so that it can only be used with unbound
workqueues.
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
syzbot found a flush_work() caller who forgot to call INIT_WORK()
because that work_struct was allocated by kzalloc() [1]. But the message
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
by lock_map_acquire() is failing to tell that INIT_WORK() is missing.
Since flush_work() without INIT_WORK() is a bug, and INIT_WORK() should
set ->func field to non-zero, let's warn if ->func field is zero.
[1] https://syzkaller.appspot.com/bug?id=a5954455fcfa51c29ca2ab55b203076337e1c770
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Tejun Heo <tj@kernel.org>
Now that call_rcu()'s callback is not invoked until after all
preempt-disable regions of code have completed (in addition to explicitly
marked RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_sched(). This commit therefore makes that change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Some architectures need to use stop_machine() to patch functions for
ftrace, and the assumption is that the stopped CPUs do not make function
calls to traceable functions when they are in the stopped state.
Commit ce4f06dcbb ("stop_machine: Touch_nmi_watchdog() after
MULTI_STOP_PREPARE") added calls to the watchdog touch functions from
the stopped CPUs and those functions lack notrace annotations. This
leads to crashes when enabling/disabling ftrace on ARM kernels built
with the Thumb-2 instruction set.
Fix it by adding the necessary notrace annotations.
Fixes: ce4f06dcbb ("stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE")
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: oleg@redhat.com
Cc: tj@kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180821152507.18313-1-vincent.whitchurch@axis.com
