Commit Graph

1657 Commits

Author SHA1 Message Date
Paul E. McKenney ae91aa0adb rcu: Remove debugfs tracing
RCU's debugfs tracing used to be the only reasonable low-level debug
information available, but ftrace and event tracing has since surpassed
the RCU debugfs level of usefulness.  This commit therefore removes
RCU's debugfs tracing.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-06-08 18:52:43 -07:00
Paul E. McKenney bd8cc5a062 srcu: Remove Classic SRCU
Classic SRCU was only ever intended to be a fallback in case of issues
with Tree/Tiny SRCU, and the latter two are doing quite well in testing.
This commit therefore removes Classic SRCU.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-06-08 18:52:42 -07:00
Paul E. McKenney f7a10a9750 rcu: Remove the RCU_KTHREAD_PRIO Kconfig option
Anything that can be done with the RCU_KTHREAD_PRIO Kconfig option can
also be done with the rcutree.kthread_prio kernel boot parameter.
This commit therefore removes this Kconfig option.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
2017-06-08 18:52:39 -07:00
Paul E. McKenney 2464dd940e srcu: Apply trivial callback lists to shrink Tiny SRCU
The rcu_segcblist structure provides quite a bit of functionality, and
Tiny SRCU needs almost none of it.  So this commit replaces Tiny SRCU's
uses of rcu_segcblist with a simple singly linked list with tail pointer.
This change significantly reduces Tiny SRCU's memory footprint, more
than making up for the growth caused by the creation of rcu_segcblist.c

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-06-08 18:52:35 -07:00
Paul E. McKenney 07f6e64bf2 srcu: Make SRCU be once again optional
Commit d160a727c4 ("srcu: Make SRCU be built by default") in response
to build errors, which were caused by code that included srcu.h
despite !SRCU.  However, srcutiny.o is almost 2K of code, which is not
insignificant for those attempting to run the Linux kernel on IoT devices.
This commit therefore makes SRCU be once again optional, and adjusts
srcu.h to allow error-free inclusion in !SRCU kernel builds.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
2017-06-08 08:25:38 -07:00
Thomas Gleixner 1c3c5eab17 sched/core: Enable might_sleep() and smp_processor_id() checks early
might_sleep() and smp_processor_id() checks are enabled after the boot
process is done. That hides bugs in the SMP bringup and driver
initialization code.

Enable it right when the scheduler starts working, i.e. when init task and
kthreadd have been created and right before the idle task enables
preemption.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170516184736.272225698@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-23 10:01:38 +02:00
Thomas Gleixner 8fb12156b8 init: Pin init task to the boot CPU, initially
Some of the boot code in init_kernel_freeable() which runs before SMP
bringup assumes (rightfully) that it runs on the boot CPU and therefore can
use smp_processor_id() in preemptible context.

That works so far because the smp_processor_id() check starts to be
effective after smp bringup. That's just wrong. Starting with SMP bringup
and the ability to move threads around, smp_processor_id() in preemptible
context is broken.

Aside of that it does not make sense to allow init to run on all CPUs
before sched_smp_init() has been run.

Pin the init to the boot CPU so the existing code can continue to use
smp_processor_id() without triggering the checks when the enabling of those
checks starts earlier.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170516184734.943149935@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-23 10:01:34 +02:00
Linus Torvalds de4d195308 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes are:

   - Debloat RCU headers

   - Parallelize SRCU callback handling (plus overlapping patches)

   - Improve the performance of Tree SRCU on a CPU-hotplug stress test

   - Documentation updates

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits)
  rcu: Open-code the rcu_cblist_n_lazy_cbs() function
  rcu: Open-code the rcu_cblist_n_cbs() function
  rcu: Open-code the rcu_cblist_empty() function
  rcu: Separately compile large rcu_segcblist functions
  srcu: Debloat the <linux/rcu_segcblist.h> header
  srcu: Adjust default auto-expediting holdoff
  srcu: Specify auto-expedite holdoff time
  srcu: Expedite first synchronize_srcu() when idle
  srcu: Expedited grace periods with reduced memory contention
  srcu: Make rcutorture writer stalls print SRCU GP state
  srcu: Exact tracking of srcu_data structures containing callbacks
  srcu: Make SRCU be built by default
  srcu: Fix Kconfig botch when SRCU not selected
  rcu: Make non-preemptive schedule be Tasks RCU quiescent state
  srcu: Expedite srcu_schedule_cbs_snp() callback invocation
  srcu: Parallelize callback handling
  kvm: Move srcu_struct fields to end of struct kvm
  rcu: Fix typo in PER_RCU_NODE_PERIOD header comment
  rcu: Use true/false in assignment to bool
  rcu: Use bool value directly
  ...
2017-05-10 10:30:46 -07:00
Linus Torvalds 8f3207c7ea TTY/Serial patches for 4.12-rc1
Here is the "big" TTY/Serial patch updates for 4.12-rc1
 
 Not a lot of new things here, the normal number of serial driver updates
 and additions, tiny bugs fixed, and some core files split up to make
 future changes a bit easier for Nicolas's "tiny-tty" work.
 
 All of these have been in linux-next for a while.  There will be a merge
 conflict with include/linux/serdev.h coming from the bluetooth tree
 merge, which we knew about, as we wanted some of the serdev changes to
 go in through that tree.  I'll send the expected merge result as a
 follow-on message.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the "big" TTY/Serial patch updates for 4.12-rc1

  Not a lot of new things here, the normal number of serial driver
  updates and additions, tiny bugs fixed, and some core files split up
  to make future changes a bit easier for Nicolas's "tiny-tty" work.

  All of these have been in linux-next for a while"

* tag 'tty-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (62 commits)
  serial: small Makefile reordering
  tty: split job control support into a file of its own
  tty: move baudrate handling code to a file of its own
  console: move console_init() out of tty_io.c
  serial: 8250_early: Add earlycon support for Palmchip UART
  tty: pl011: use "qdf2400_e44" as the earlycon name for QDF2400 E44
  vt: make mouse selection of non-ASCII consistent
  vt: set mouse selection word-chars to gpm's default
  imx-serial: Reduce RX DMA startup latency when opening for reading
  serial: omap: suspend device on probe errors
  serial: omap: fix runtime-pm handling on unbind
  tty: serial: omap: add UPF_BOOT_AUTOCONF flag for DT init
  serial: samsung: Remove useless spinlock
  serial: samsung: Add missing checks for dma_map_single failure
  serial: samsung: Use right device for DMA-mapping calls
  serial: imx: setup DCEDTE early and ensure DCD and RI irqs to be off
  tty: fix comment typo s/repsonsible/responsible/
  tty: amba-pl011: Fix spurious TX interrupts
  serial: xuartps: Enable clocks in the pm disable case also
  serial: core: Re-use struct uart_port {name} field
  ...
2017-05-08 18:49:23 -07:00
Arnd Bergmann 046aa1265f initramfs: use vfs_stat/lstat directly
sys_newlstat is a system call implementation that is meant for user
space, and that copies kernel-internal data structure to the user
format, which is not needed for in-kernel users.

Further, as we rearrange the system call implementation so we can extend
it with 64-bit time_t, the prototype for sys_newlstat changes.

This changes the initramfs code to use vfs_lstat directly, to get it out
of the way of the time_t changes, and make it slightly more efficient in
the process.  Along the same lines we also replace sys_stat and
sys_stat64 with vfs_stat.

Link: http://lkml.kernel.org/r/20170314214932.4052842-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Daniel Thompson cff75e0b6f initramfs: provide a way to ignore image provided by bootloader
Many "embedded" architectures provide CMDLINE_FORCE to allow the kernel
to override the command line provided by an inflexible bootloader.
However there is currrently no way for the kernel to override the
initramfs image provided by the bootloader meaning there are still ways
for bootloaders to make things difficult for us.

Fix this by introducing INITRAMFS_FORCE which can prevent the kernel
from loading the bootloader supplied image.

We use CMDLINE_FORCE (and its friend CMDLINE_EXTEND) to imply that the
system has an inflexible bootloader.  This allow us to avoid presenting
this config option to users of systems where inflexible bootloaders
aren't usually a problem.

Link: http://lkml.kernel.org/r/20170217121940.30126-1-daniel.thompson@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Linus Torvalds 394e4f5d58 initramfs: avoid "label at end of compound statement" error
Commit 17a9be3174 ("initramfs: Always do fput() and load modules after
rootfs populate") introduced an error for the

    CONFIG_BLK_DEV_RAM=y

case, because even though the code looks fine, the compiler really wants
a statement after a label, or you'll get complaints:

  init/initramfs.c: In function 'populate_rootfs':
  init/initramfs.c:644:2: error: label at end of compound statement

That commit moved the subsequent statements to outside the compound
statement, leaving the label without any associated statements.

Reported-by: Jörg Otte <jrg.otte@gmail.com>
Fixes: 17a9be3174 ("initramfs: Always do fput() and load modules after rootfs populate")
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: stable@vger.kernel.org  # if 17a9be3174 gets backported
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-06 10:27:13 -07:00
Linus Torvalds 58017a3e28 Fix for initramfs for 4.12-rc1
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Merge tag 'initramfs-fix-4.12-rc1' of git://github.com/stffrdhrn/linux

Pull initramfs fix from Stafford Horne:
 "This is a fix for an issue that has caused 4.11 to not boot on
  OpenRISC. I should have caught this during the 4.11 cycle but I had
  been busy on testing some other series of patches.

  I would have considered pushing it though a different path but Al Viro
  suggested submitting directly to you.

  Also, its just one as I havent really got anything else ready on my
  queue for 4.12.

  Summary:

   - Ensure fput() flush is done even for builtin initramfs"

* tag 'initramfs-fix-4.12-rc1' of git://github.com/stffrdhrn/linux:
  initramfs: Always do fput() and load modules after rootfs populate
2017-05-05 13:30:11 -07:00
Stafford Horne 17a9be3174 initramfs: Always do fput() and load modules after rootfs populate
In OpenRISC we do not have a bootloader passed initrd, but the built in
initramfs does contain the /init and other binaries, including modules.
The previous commit 0886551480 ("initramfs: finish fput() before
accessing any binary from initramfs") made a change to only call fput()
if the bootloader initrd was available, this caused intermittent crashes
for OpenRISC.

This patch changes the fput() to happen unconditionally if any rootfs is
loaded. Also, I added some comments to make it a bit more clear why we
call unpack_to_rootfs() multiple times.

Fixes: 0886551480 ("initramfs: finish fput() before accessing any binary from initramfs")
Cc: stable@vger.kernel.org
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Stafford Horne <shorne@gmail.com>
2017-05-05 16:01:08 +09:00
Linus Torvalds 4c174688ee New features for this release:
o Pretty much a full rewrite of the processing of function plugins.
    i.e. echo do_IRQ:stacktrace > set_ftrace_filter
 
  o The rewrite was needed to add plugins to be unique to tracing instances.
    i.e. mkdir instance/foo; cd instances/foo; echo do_IRQ:stacktrace > set_ftrace_filter
    The old way was written very hacky. This removes a lot of those hacks.
 
  o New "function-fork" tracing option. When set, pids in the set_ftrace_pid
    will have their children added when the processes with their pids
    listed in the set_ftrace_pid file forks.
 
  o Exposure of "maxactive" for kretprobe in kprobe_events
 
  o Allow for builtin init functions to be traced by the function tracer
    (via the kernel command line). Module init function tracing will come
    in the next release.
 
  o Added more selftests, and have selftests also test in an instance.
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Merge tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "New features for this release:

   - Pretty much a full rewrite of the processing of function plugins.
     i.e. echo do_IRQ:stacktrace > set_ftrace_filter

   - The rewrite was needed to add plugins to be unique to tracing
     instances. i.e. mkdir instance/foo; cd instances/foo; echo
     do_IRQ:stacktrace > set_ftrace_filter The old way was written very
     hacky. This removes a lot of those hacks.

   - New "function-fork" tracing option. When set, pids in the
     set_ftrace_pid will have their children added when the processes
     with their pids listed in the set_ftrace_pid file forks.

   - Exposure of "maxactive" for kretprobe in kprobe_events

   - Allow for builtin init functions to be traced by the function
     tracer (via the kernel command line). Module init function tracing
     will come in the next release.

   - Added more selftests, and have selftests also test in an instance"

* tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (60 commits)
  ring-buffer: Return reader page back into existing ring buffer
  selftests: ftrace: Allow some event trigger tests to run in an instance
  selftests: ftrace: Have some basic tests run in a tracing instance too
  selftests: ftrace: Have event tests also run in an tracing instance
  selftests: ftrace: Make func_event_triggers and func_traceonoff_triggers tests do instances
  selftests: ftrace: Allow some tests to be run in a tracing instance
  tracing/ftrace: Allow for instances to trigger their own stacktrace probes
  tracing/ftrace: Allow for the traceonoff probe be unique to instances
  tracing/ftrace: Enable snapshot function trigger to work with instances
  tracing/ftrace: Allow instances to have their own function probes
  tracing/ftrace: Add a better way to pass data via the probe functions
  ftrace: Dynamically create the probe ftrace_ops for the trace_array
  tracing: Pass the trace_array into ftrace_probe_ops functions
  tracing: Have the trace_array hold the list of registered func probes
  ftrace: If the hash for a probe fails to update then free what was initialized
  ftrace: Have the function probes call their own function
  ftrace: Have each function probe use its own ftrace_ops
  ftrace: Have unregister_ftrace_function_probe_func() return a value
  ftrace: Add helper function ftrace_hash_move_and_update_ops()
  ftrace: Remove data field from ftrace_func_probe structure
  ...
2017-05-03 18:41:21 -07:00
Linus Torvalds 89c9fea3c8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  tty: fix comment for __tty_alloc_driver()
  init/main: properly align the multi-line comment
  init/main: Fix double "the" in comment
  Fix dead URLs to ftp.kernel.org
  drivers: Clean up duplicated email address
  treewide: Fix typo in xml/driver-api/basics.xml
  tools/testing/selftests/powerpc: remove redundant CFLAGS in Makefile: "-Wall -O2 -Wall" -> "-O2 -Wall"
  selftests/timers: Spelling s/privledges/privileges/
  HID: picoLCD: Spelling s/REPORT_WRTIE_MEMORY/REPORT_WRITE_MEMORY/
  net: phy: dp83848: Fix Typo
  UBI: Fix typos
  Documentation: ftrace.txt: Correct nice value of 120 priority
  net: fec: Fix typo in error msg and comment
  treewide: Fix typos in printk
2017-05-02 19:09:35 -07:00
Paul E. McKenney 98059b9861 rcu: Separately compile large rcu_segcblist functions
This commit creates a new kernel/rcu/rcu_segcblist.c file that
contains non-trivial segcblist functions.  Trivial functions
remain as static inline functions in kernel/rcu/rcu_segcblist.h

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2017-05-02 07:21:02 -07:00
Paul E. McKenney d160a727c4 srcu: Make SRCU be built by default
SRCU is optional, and included only if there is a "select SRCU" in effect.
However, we now have Tiny SRCU, so this commit defaults CONFIG_SRCU=y.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-04-24 08:36:02 -07:00
Viresh Kumar 1b3b3b49b9 init/main: properly align the multi-line comment
Add a tab before it to follow standard practices. Also add the missing
full stop '.'.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-04-24 13:14:21 +02:00
Viresh Kumar 6623f1c615 init/main: Fix double "the" in comment
s/the\ the/the

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-04-24 13:14:21 +02:00
Paul E. McKenney 677df9d461 srcu: Fix Kconfig botch when SRCU not selected
If the CONFIG_SRCU option is not selected, for example, when building
arch/tile allnoconfig, the following build errors appear:

	kernel/rcu/tree.o: In function `srcu_online_cpu':
	tree.c:(.text+0x4248): multiple definition of `srcu_online_cpu'
	kernel/rcu/srcutree.o:srcutree.c:(.text+0x2120): first defined here
	kernel/rcu/tree.o: In function `srcu_offline_cpu':
	tree.c:(.text+0x4250): multiple definition of `srcu_offline_cpu'
	kernel/rcu/srcutree.o:srcutree.c:(.text+0x2160): first defined here

The corresponding .config file shows CONFIG_TREE_SRCU=y, but no sign
of CONFIG_SRCU, which fatally confuses SRCU's #ifdefs, resulting in
the above errors.  The reason this occurs is the folowing line in
init/Kconfig's definition for TREE_SRCU:

	default y if !TINY_RCU && !CLASSIC_SRCU

If CONFIG_CLASSIC_SRCU=n, as it will be in for allnoconfig, and if
CONFIG_SMP=y, then we will get CONFIG_TREE_SRCU=y but no CONFIG_SRCU,
as seen in the .config file, and which will result in the above errors.
This error did not show up during rcutorture testing because rcutorture
forces CONFIG_SRCU=y, as it must to prevent build errors in rcutorture.c.

This commit therefore conditions TREE_SRCU (and TINY_SRCU, while it is
at it) with SRCU, like this:

	default y if SRCU && !TINY_RCU && !CLASSIC_SRCU

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20170423162205.GP3956@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-24 08:14:48 +02:00
Ingo Molnar 58d30c36d4 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 - Documentation updates.

 - Miscellaneous fixes.

 - Parallelize SRCU callback handling (plus overlapping patches).

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-23 11:12:44 +02:00
Paul E. McKenney f2094107ac Merge branches 'doc.2017.04.12a', 'fixes.2017.04.19a' and 'srcu.2017.04.21a' into HEAD
doc.2017.04.12a: Documentation updates
fixes.2017.04.19a: Miscellaneous fixes
srcu.2017.04.21a: Parallelize SRCU callback handling
2017-04-21 06:00:13 -07:00
Paul E. McKenney 0248288009 rcu: Make RCU_FANOUT_LEAF help text more explicit about skew_tick
If you set RCU_FANOUT_LEAF too high, you can get lock contention
on the leaf rcu_node, and you should boot with the skew_tick kernel
parameter set in order to avoid this lock contention.  This commit
therefore upgrades the RCU_FANOUT_LEAF help text to explicitly state
this.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-04-19 09:29:17 -07:00
Paul E. McKenney dad81a2026 srcu: Introduce CLASSIC_SRCU Kconfig option
The TREE_SRCU rewrite is large and a bit on the non-simple side, so
this commit helps reduce risk by allowing the old v4.11 SRCU algorithm
to be selected using a new CLASSIC_SRCU Kconfig option that depends
on RCU_EXPERT.  The default is to use the new TREE_SRCU and TINY_SRCU
algorithms, in order to help get these the testing that they need.
However, if your users do not require the update-side scalability that
is to be provided by TREE_SRCU, select RCU_EXPERT and then CLASSIC_SRCU
to revert back to the old classic SRCU algorithm.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-04-18 11:38:23 -07:00
Paul E. McKenney d8be81735a srcu: Create a tiny SRCU
In response to automated complaints about modifications to SRCU
increasing its size, this commit creates a tiny SRCU that is
used in SMP=n && PREEMPT=n builds.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-04-18 11:38:22 -07:00
Nicolas Pitre 0c688614dc console: move console_init() out of tty_io.c
All the console driver handling code lives in printk.c.
Move console_init() there as well so console support can still be used
when the TTY code is configured out. No logical changes from this patch.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18 18:01:52 +02:00
Steven Rostedt (VMware) b80f0f6c9e ftrace: Have init/main.c call ftrace directly to free init memory
Relying on free_reserved_area() to call ftrace to free init memory proved to
not be sufficient. The issue is that on x86, when debug_pagealloc is
enabled, the init memory is not freed, but simply set as not present. Since
ftrace was uninformed of this, starting function tracing still tries to
update pages that are not present according to the page tables, causing
ftrace to bug, as well as killing the kernel itself.

Instead of relying on free_reserved_area(), have init/main.c call ftrace
directly just before it frees the init memory. Then it needs to use
__init_begin and __init_end to know where the init memory location is.
Looking at all archs (and testing what I can), it appears that this should
work for each of them.

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-04-03 14:04:00 -04:00
Michal Hocko 597b7305dd mm: move mm_percpu_wq initialization earlier
Yang Li has reported that drain_all_pages triggers a WARN_ON which means
that this function is called earlier than the mm_percpu_wq is
initialized on arm64 with CMA configured:

  WARNING: CPU: 2 PID: 1 at mm/page_alloc.c:2423 drain_all_pages+0x244/0x25c
  Modules linked in:
  CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc1-next-20170310-00027-g64dfbc5 #127
  Hardware name: Freescale Layerscape 2088A RDB Board (DT)
  task: ffffffc07c4a6d00 task.stack: ffffffc07c4a8000
  PC is at drain_all_pages+0x244/0x25c
  LR is at start_isolate_page_range+0x14c/0x1f0
  [...]
   drain_all_pages+0x244/0x25c
   start_isolate_page_range+0x14c/0x1f0
   alloc_contig_range+0xec/0x354
   cma_alloc+0x100/0x1fc
   dma_alloc_from_contiguous+0x3c/0x44
   atomic_pool_init+0x7c/0x208
   arm64_dma_init+0x44/0x4c
   do_one_initcall+0x38/0x128
   kernel_init_freeable+0x1a0/0x240
   kernel_init+0x10/0xfc
   ret_from_fork+0x10/0x20

Fix this by moving the whole setup_vmstat which is an initcall right now
to init_mm_internals which will be called right after the WQ subsystem
is initialized.

Link: http://lkml.kernel.org/r/20170315164021.28532-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Yang Li <pku.leo@gmail.com>
Tested-by: Yang Li <pku.leo@gmail.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-31 17:13:30 -07:00
Steven Rostedt (VMware) f631718de3 ftrace: Move ftrace_init() to right after memory initialization
Initialize the ftrace records immediately after memory initialization, as
that is all that is required for the records to be created. This will allow
for future work to get function tracing started earlier in the boot process.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-24 13:08:44 -04:00
Steven Rostedt (VMware) e725c731e3 tracing: Split tracing initialization into two for early initialization
Create an early_trace_init() function that will initialize the buffers and
allow for ealier use of trace_printk(). This will also allow for future work
to have function tracing start earlier at boot up.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-24 13:08:43 -04:00
Linus Torvalds 84c37c168c Change get_random_{int,log} to use the CRNG used by /dev/urandom and
getrandom(2).  It's faster and arguably more secure than cut-down MD5
 that we had been using.
 
 Also do some code cleanup.
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Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

Pull random updates from Ted Ts'o:
 "Change get_random_{int,log} to use the CRNG used by /dev/urandom and
  getrandom(2). It's faster and arguably more secure than cut-down MD5
  that we had been using.

  Also do some code cleanup"

* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: move random_min_urandom_seed into CONFIG_SYSCTL ifdef block
  random: convert get_random_int/long into get_random_u32/u64
  random: use chacha20 for get_random_int/long
  random: fix comment for unused random_min_urandom_seed
  random: remove variable limit
  random: remove stale urandom_init_wait
  random: remove stale maybe_reseed_primary_crng
2017-03-11 09:08:47 -08:00
Ingo Molnar 1777e46355 sched/headers: Prepare to move _init() prototypes from <linux/sched.h> to <linux/sched/init.h>
But first introduce a trivial header and update usage sites.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:40 +01:00
Ingo Molnar 5c2c5c5514 sched/headers, vfs/execve: Prepare to move the do_execve*() prototypes from <linux/sched.h> to <linux/binfmts.h>
But first update the usage sites with the new header dependency.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:39 +01:00
Ingo Molnar 9164bb4a18 sched/headers: Prepare to move 'init_task' and 'init_thread_union' from <linux/sched.h> to <linux/sched/task.h>
Update all usage sites first.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:38 +01:00
Ingo Molnar 68db0cf106 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:36 +01:00
Ingo Molnar 299300258d sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>
We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:35 +01:00
Ingo Molnar 38b8d208a4 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/nmi.h>
We are going to move softlockup APIs out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

<linux/nmi.h> already includes <linux/sched.h>.

Include the <linux/nmi.h> header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:30 +01:00
Linus Torvalds cf393195c3 Merge branch 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax
Pull IDR rewrite from Matthew Wilcox:
 "The most significant part of the following is the patch to rewrite the
  IDR & IDA to be clients of the radix tree. But there's much more,
  including an enhancement of the IDA to be significantly more space
  efficient, an IDR & IDA test suite, some improvements to the IDR API
  (and driver changes to take advantage of those improvements), several
  improvements to the radix tree test suite and RCU annotations.

  The IDR & IDA rewrite had a good spin in linux-next and Andrew's tree
  for most of the last cycle. Coupled with the IDR test suite, I feel
  pretty confident that any remaining bugs are quite hard to hit. 0-day
  did a great job of watching my git tree and pointing out problems; as
  it hit them, I added new test-cases to be sure not to be caught the
  same way twice"

Willy goes on to expand a bit on the IDR rewrite rationale:
 "The radix tree and the IDR use very similar data structures.

  Merging the two codebases lets us share the memory allocation pools,
  and results in a net deletion of 500 lines of code. It also opens up
  the possibility of exposing more of the features of the radix tree to
  users of the IDR (and I have some interesting patches along those
  lines waiting for 4.12)

  It also shrinks the size of the 'struct idr' from 40 bytes to 24 which
  will shrink a fair few data structures that embed an IDR"

* 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax: (32 commits)
  radix tree test suite: Add config option for map shift
  idr: Add missing __rcu annotations
  radix-tree: Fix __rcu annotations
  radix-tree: Add rcu_dereference and rcu_assign_pointer calls
  radix tree test suite: Run iteration tests for longer
  radix tree test suite: Fix split/join memory leaks
  radix tree test suite: Fix leaks in regression2.c
  radix tree test suite: Fix leaky tests
  radix tree test suite: Enable address sanitizer
  radix_tree_iter_resume: Fix out of bounds error
  radix-tree: Store a pointer to the root in each node
  radix-tree: Chain preallocated nodes through ->parent
  radix tree test suite: Dial down verbosity with -v
  radix tree test suite: Introduce kmalloc_verbose
  idr: Return the deleted entry from idr_remove
  radix tree test suite: Build separate binaries for some tests
  ida: Use exceptional entries for small IDAs
  ida: Move ida_bitmap to a percpu variable
  Reimplement IDR and IDA using the radix tree
  radix-tree: Add radix_tree_iter_delete
  ...
2017-02-28 20:29:41 -08:00
Linus Torvalds 86292b33d4 Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - a few MM remainders

 - misc things

 - autofs updates

 - signals

 - affs updates

 - ipc

 - nilfs2

 - spelling.txt updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (78 commits)
  mm, x86: fix HIGHMEM64 && PARAVIRT build config for native_pud_clear()
  mm: add arch-independent testcases for RODATA
  hfs: atomically read inode size
  mm: clarify mm_struct.mm_{users,count} documentation
  mm: use mmget_not_zero() helper
  mm: add new mmget() helper
  mm: add new mmgrab() helper
  checkpatch: warn when formats use %Z and suggest %z
  lib/vsprintf.c: remove %Z support
  scripts/spelling.txt: add some typo-words
  scripts/spelling.txt: add "followings" pattern and fix typo instances
  scripts/spelling.txt: add "therfore" pattern and fix typo instances
  scripts/spelling.txt: add "overwriten" pattern and fix typo instances
  scripts/spelling.txt: add "overwritting" pattern and fix typo instances
  scripts/spelling.txt: add "deintialize(d)" pattern and fix typo instances
  scripts/spelling.txt: add "disassocation" pattern and fix typo instances
  scripts/spelling.txt: add "omited" pattern and fix typo instances
  scripts/spelling.txt: add "explictely" pattern and fix typo instances
  scripts/spelling.txt: add "applys" pattern and fix typo instances
  scripts/spelling.txt: add "configuartion" pattern and fix typo instances
  ...
2017-02-27 23:09:29 -08:00
Linus Torvalds f7878dc3a9 Merge branch 'for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "Several noteworthy changes.

   - Parav's rdma controller is finally merged. It is very straight
     forward and can limit the abosolute numbers of common rdma
     constructs used by different cgroups.

   - kernel/cgroup.c got too chubby and disorganized. Created
     kernel/cgroup/ subdirectory and moved all cgroup related files
     under kernel/ there and reorganized the core code. This hurts for
     backporting patches but was long overdue.

   - cgroup v2 process listing reimplemented so that it no longer
     depends on allocating a buffer large enough to cache the entire
     result to sort and uniq the output. v2 has always mangled the sort
     order to ensure that users don't depend on the sorted output, so
     this shouldn't surprise anybody. This makes the pid listing
     functions use the same iterators that are used internally, which
     have to have the same iterating capabilities anyway.

   - perf cgroup filtering now works automatically on cgroup v2. This
     patch was posted a long time ago but somehow fell through the
     cracks.

   - misc fixes asnd documentation updates"

* 'for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (27 commits)
  kernfs: fix locking around kernfs_ops->release() callback
  cgroup: drop the matching uid requirement on migration for cgroup v2
  cgroup, perf_event: make perf_event controller work on cgroup2 hierarchy
  cgroup: misc cleanups
  cgroup: call subsys->*attach() only for subsystems which are actually affected by migration
  cgroup: track migration context in cgroup_mgctx
  cgroup: cosmetic update to cgroup_taskset_add()
  rdmacg: Fixed uninitialized current resource usage
  cgroup: Add missing cgroup-v2 PID controller documentation.
  rdmacg: Added documentation for rdmacg
  IB/core: added support to use rdma cgroup controller
  rdmacg: Added rdma cgroup controller
  cgroup: fix a comment typo
  cgroup: fix RCU related sparse warnings
  cgroup: move namespace code to kernel/cgroup/namespace.c
  cgroup: rename functions for consistency
  cgroup: move v1 mount functions to kernel/cgroup/cgroup-v1.c
  cgroup: separate out cgroup1_kf_syscall_ops
  cgroup: refactor mount path and clearly distinguish v1 and v2 paths
  cgroup: move cgroup v1 specific code to kernel/cgroup/cgroup-v1.c
  ...
2017-02-27 21:41:08 -08:00
Jinbum Park 2959a5f726 mm: add arch-independent testcases for RODATA
This patch makes arch-independent testcases for RODATA.  Both x86 and
x86_64 already have testcases for RODATA, But they are arch-specific
because using inline assembly directly.

And cacheflush.h is not a suitable location for rodata-test related
things.  Since they were in cacheflush.h, If someone change the state of
CONFIG_DEBUG_RODATA_TEST, It cause overhead of kernel build.

To solve the above issues, write arch-independent testcases and move it
to shared location.

[jinb.park7@gmail.com: fix config dependency]
  Link: http://lkml.kernel.org/r/20170209131625.GA16954@pjb1027-Latitude-E5410
Link: http://lkml.kernel.org/r/20170129105436.GA9303@pjb1027-Latitude-E5410
Signed-off-by: Jinbum Park <jinb.park7@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:48 -08:00
Lokesh Vutla 0886551480 initramfs: finish fput() before accessing any binary from initramfs
Commit 4a9d4b024a ("switch fput to task_work_add") implements a
schedule_work() for completing fput(), but did not guarantee calling
__fput() after unpacking initramfs.  Because of this, there is a
possibility that during boot a driver can see ETXTBSY when it tries to
load a binary from initramfs as fput() is still pending on that binary.

This patch makes sure that fput() is completed after unpacking initramfs
and removes the call to flush_delayed_fput() in kernel_init() which
happens very late after unpacking initramfs.

Link: http://lkml.kernel.org/r/20170201140540.22051-1-lokeshvutla@ti.com
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reported-by: Murali Karicheri <m-karicheri2@ti.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27 18:43:46 -08:00
Linus Torvalds bc49a7831b Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
 "142 patches:

   - DAX updates

   - various misc bits

   - OCFS2 updates

   - most of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (142 commits)
  mm/z3fold.c: limit first_num to the actual range of possible buddy indexes
  mm: fix <linux/pagemap.h> stray kernel-doc notation
  zram: remove obsolete sysfs attrs
  mm/memblock.c: remove unnecessary log and clean up
  oom-reaper: use madvise_dontneed() logic to decide if unmap the VMA
  mm: drop unused argument of zap_page_range()
  mm: drop zap_details::check_swap_entries
  mm: drop zap_details::ignore_dirty
  mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled
  mm: help __GFP_NOFAIL allocations which do not trigger OOM killer
  mm, oom: do not enforce OOM killer for __GFP_NOFAIL automatically
  mm: consolidate GFP_NOFAIL checks in the allocator slowpath
  lib/show_mem.c: teach show_mem to work with the given nodemask
  arch, mm: remove arch specific show_mem
  mm, page_alloc: warn_alloc print nodemask
  mm, page_alloc: do not report all nodes in show_mem
  Revert "mm: bail out in shrink_inactive_list()"
  mm, vmscan: consider eligible zones in get_scan_count
  mm, vmscan: cleanup lru size claculations
  mm, vmscan: do not count freed pages as PGDEACTIVATE
  ...
2017-02-22 19:29:24 -08:00
Linus Torvalds 7d91de7443 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:

 - Add Petr Mladek, Sergey Senozhatsky as printk maintainers, and Steven
   Rostedt as the printk reviewer. This idea came up after the
   discussion about printk issues at Kernel Summit. It was formulated
   and discussed at lkml[1].

 - Extend a lock-less NMI per-cpu buffers idea to handle recursive
   printk() calls by Sergey Senozhatsky[2]. It is the first step in
   sanitizing printk as discussed at Kernel Summit.

   The change allows to see messages that would normally get ignored or
   would cause a deadlock.

   Also it allows to enable lockdep in printk(). This already paid off.
   The testing in linux-next helped to discover two old problems that
   were hidden before[3][4].

 - Remove unused parameter by Sergey Senozhatsky. Clean up after a past
   change.

[1] http://lkml.kernel.org/r/1481798878-31898-1-git-send-email-pmladek@suse.com
[2] http://lkml.kernel.org/r/20161227141611.940-1-sergey.senozhatsky@gmail.com
[3] http://lkml.kernel.org/r/20170215044332.30449-1-sergey.senozhatsky@gmail.com
[4] http://lkml.kernel.org/r/20170217015932.11898-1-sergey.senozhatsky@gmail.com

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  printk: drop call_console_drivers() unused param
  printk: convert the rest to printk-safe
  printk: remove zap_locks() function
  printk: use printk_safe buffers in printk
  printk: report lost messages in printk safe/nmi contexts
  printk: always use deferred printk when flush printk_safe lines
  printk: introduce per-cpu safe_print seq buffer
  printk: rename nmi.c and exported api
  printk: use vprintk_func in vprintk()
  MAINTAINERS: Add printk maintainers
2017-02-22 17:33:34 -08:00
Tejun Heo 1663f26df3 slub: make sysfs directories for memcg sub-caches optional
SLUB creates a per-cache directory under /sys/kernel/slab which hosts a
bunch of debug files.  Usually, there aren't that many caches on a
system and this doesn't really matter; however, if memcg is in use, each
cache can have per-cgroup sub-caches.  SLUB creates the same directories
for these sub-caches under /sys/kernel/slab/$CACHE/cgroup.

Unfortunately, because there can be a lot of cgroups, active or
draining, the product of the numbers of caches, cgroups and files in
each directory can reach a very high number - hundreds of thousands is
commonplace.  Millions and beyond aren't difficult to reach either.

What's under /sys/kernel/slab is primarily for debugging and the
information and control on the a root cache already cover its
sub-caches.  While having a separate directory for each sub-cache can be
helpful for development, it doesn't make much sense to pay this amount
of overhead by default.

This patch introduces a boot parameter slub_memcg_sysfs which determines
whether to create sysfs directories for per-memcg sub-caches.  It also
adds CONFIG_SLUB_MEMCG_SYSFS_ON which determines the boot parameter's
default value and defaults to 0.

[akpm@linux-foundation.org: kset_unregister(NULL) is legal]
Link: http://lkml.kernel.org/r/20170204145203.GB26958@mtj.duckdns.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22 16:41:27 -08:00
Linus Torvalds e30aee9e10 char/misc driver patches for 4.11-rc1
Here is the big char/misc driver patchset for 4.11-rc1.
 
 Lots of different driver subsystems updated here.  Rework for the hyperv
 subsystem to handle new platforms better, mei and w1 and extcon driver
 updates, as well as a number of other "minor" driver updates.  Full
 details are in the shortlog below.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big char/misc driver patchset for 4.11-rc1.

  Lots of different driver subsystems updated here: rework for the
  hyperv subsystem to handle new platforms better, mei and w1 and extcon
  driver updates, as well as a number of other "minor" driver updates.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (169 commits)
  goldfish: Sanitize the broken interrupt handler
  x86/platform/goldfish: Prevent unconditional loading
  vmbus: replace modulus operation with subtraction
  vmbus: constify parameters where possible
  vmbus: expose hv_begin/end_read
  vmbus: remove conditional locking of vmbus_write
  vmbus: add direct isr callback mode
  vmbus: change to per channel tasklet
  vmbus: put related per-cpu variable together
  vmbus: callback is in softirq not workqueue
  binder: Add support for file-descriptor arrays
  binder: Add support for scatter-gather
  binder: Add extra size to allocator
  binder: Refactor binder_transact()
  binder: Support multiple /dev instances
  binder: Deal with contexts in debugfs
  binder: Support multiple context managers
  binder: Split flat_binder_object
  auxdisplay: ht16k33: remove private workqueue
  auxdisplay: ht16k33: rework input device initialization
  ...
2017-02-22 11:38:22 -08:00
Linus Torvalds 7bb033829e This renames the (now inaccurate) CONFIG_DEBUG_RODATA and related config
CONFIG_SET_MODULE_RONX to the more sensible CONFIG_STRICT_KERNEL_RWX and
 CONFIG_STRICT_MODULE_RWX.
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Merge tag 'rodata-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull rodata updates from Kees Cook:
 "This renames the (now inaccurate) DEBUG_RODATA and related
  SET_MODULE_RONX configs to the more sensible STRICT_KERNEL_RWX and
  STRICT_MODULE_RWX"

* tag 'rodata-v4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  arch: Rename CONFIG_DEBUG_RODATA and CONFIG_DEBUG_MODULE_RONX
  arch: Move CONFIG_DEBUG_RODATA and CONFIG_SET_MODULE_RONX to be common
2017-02-21 17:56:45 -08:00
Linus Torvalds 6d1c42d9b9 Final extable.h related changes.
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Merge tag 'extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull exception table module split from Paul Gortmaker:
 "Final extable.h related changes.

  This completes the separation of exception table content from the
  module.h header file. This is achieved with the final commit that
  removes the one line back compatible change that sourced extable.h
  into the module.h file.

  The commits are unchanged since January, with the exception of a
  couple Acks that came in for the last two commits a bit later. The
  changes have been in linux-next for quite some time[1] and have got
  widespread arch coverage via toolchains I have and also from
  additional ones the kbuild bot has.

  Maintaners of the various arch were Cc'd during the postings to
  lkml[2] and informed that the intention was to take the remaining arch
  specific changes and lump them together with the final two non-arch
  specific changes and submit for this merge window.

  The ia64 diffstat stands out and probably warrants a mention. In an
  earlier review, Al Viro made a valid comment that the original header
  separation of content left something to be desired, and that it get
  fixed as a part of this change, hence the larger diffstat"

* tag 'extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (21 commits)
  module.h: remove extable.h include now users have migrated
  core: migrate exception table users off module.h and onto extable.h
  cris: migrate exception table users off module.h and onto extable.h
  hexagon: migrate exception table users off module.h and onto extable.h
  microblaze: migrate exception table users off module.h and onto extable.h
  unicore32: migrate exception table users off module.h and onto extable.h
  score: migrate exception table users off module.h and onto extable.h
  metag: migrate exception table users off module.h and onto extable.h
  arc: migrate exception table users off module.h and onto extable.h
  nios2: migrate exception table users off module.h and onto extable.h
  sparc: migrate exception table users onto extable.h
  openrisc: migrate exception table users off module.h and onto extable.h
  frv: migrate exception table users off module.h and onto extable.h
  sh: migrate exception table users off module.h and onto extable.h
  xtensa: migrate exception table users off module.h and onto extable.h
  mn10300: migrate exception table users off module.h and onto extable.h
  alpha: migrate exception table users off module.h and onto extable.h
  arm: migrate exception table users off module.h and onto extable.h
  m32r: migrate exception table users off module.h and onto extable.h
  ia64: ensure exception table search users include extable.h
  ...
2017-02-21 14:28:55 -08:00
Linus Torvalds 42e1b14b6e Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Implement wraparound-safe refcount_t and kref_t types based on
     generic atomic primitives (Peter Zijlstra)

   - Improve and fix the ww_mutex code (Nicolai Hähnle)

   - Add self-tests to the ww_mutex code (Chris Wilson)

   - Optimize percpu-rwsems with the 'rcuwait' mechanism (Davidlohr
     Bueso)

   - Micro-optimize the current-task logic all around the core kernel
     (Davidlohr Bueso)

   - Tidy up after recent optimizations: remove stale code and APIs,
     clean up the code (Waiman Long)

   - ... plus misc fixes, updates and cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
  fork: Fix task_struct alignment
  locking/spinlock/debug: Remove spinlock lockup detection code
  lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKS
  lkdtm: Convert to refcount_t testing
  kref: Implement 'struct kref' using refcount_t
  refcount_t: Introduce a special purpose refcount type
  sched/wake_q: Clarify queue reinit comment
  sched/wait, rcuwait: Fix typo in comment
  locking/mutex: Fix lockdep_assert_held() fail
  locking/rtmutex: Flip unlikely() branch to likely() in __rt_mutex_slowlock()
  locking/rwsem: Reinit wake_q after use
  locking/rwsem: Remove unnecessary atomic_long_t casts
  jump_labels: Move header guard #endif down where it belongs
  locking/atomic, kref: Implement kref_put_lock()
  locking/ww_mutex: Turn off __must_check for now
  locking/atomic, kref: Avoid more abuse
  locking/atomic, kref: Use kref_get_unless_zero() more
  locking/atomic, kref: Kill kref_sub()
  locking/atomic, kref: Add kref_read()
  locking/atomic, kref: Add KREF_INIT()
  ...
2017-02-20 13:23:30 -08:00
Linus Torvalds 828cad8ea0 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this (fairly busy) cycle were:

   - There was a class of scheduler bugs related to forgetting to update
     the rq-clock timestamp which can cause weird and hard to debug
     problems, so there's a new debug facility for this: which uncovered
     a whole lot of bugs which convinced us that we want to keep the
     debug facility.

     (Peter Zijlstra, Matt Fleming)

   - Various cputime related updates: eliminate cputime and use u64
     nanoseconds directly, simplify and improve the arch interfaces,
     implement delayed accounting more widely, etc. - (Frederic
     Weisbecker)

   - Move code around for better structure plus cleanups (Ingo Molnar)

   - Move IO schedule accounting deeper into the scheduler plus related
     changes to improve the situation (Tejun Heo)

   - ... plus a round of sched/rt and sched/deadline fixes, plus other
     fixes, updats and cleanups"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (85 commits)
  sched/core: Remove unlikely() annotation from sched_move_task()
  sched/autogroup: Rename auto_group.[ch] to autogroup.[ch]
  sched/topology: Split out scheduler topology code from core.c into topology.c
  sched/core: Remove unnecessary #include headers
  sched/rq_clock: Consolidate the ordering of the rq_clock methods
  delayacct: Include <uapi/linux/taskstats.h>
  sched/core: Clean up comments
  sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds
  sched/clock: Add dummy clear_sched_clock_stable() stub function
  sched/cputime: Remove generic asm headers
  sched/cputime: Remove unused nsec_to_cputime()
  s390, sched/cputime: Remove unused cputime definitions
  powerpc, sched/cputime: Remove unused cputime definitions
  s390, sched/cputime: Make arch_cpu_idle_time() to return nsecs
  ia64, sched/cputime: Remove unused cputime definitions
  ia64: Convert vtime to use nsec units directly
  ia64, sched/cputime: Move the nsecs based cputime headers to the last arch using it
  sched/cputime: Remove jiffies based cputime
  sched/cputime, vtime: Return nsecs instead of cputime_t to account
  sched/cputime: Complete nsec conversion of tick based accounting
  ...
2017-02-20 12:52:55 -08:00
Linus Torvalds 32e2d7c8af Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Changes to the EFI init code to establish whether secure boot
     authentication was performed at boot time. (Josh Boyer, David
     Howells)

   - Wire up the UEFI memory attributes table for x86. This eliminates
     any runtime memory regions that are both writable and executable,
     on recent firmware versions. (Sai Praneeth)

   - Move the BGRT init code to an earlier stage so that we can still
     use efi_mem_reserve(). (Dave Young)

   - Preserve debug symbols in the ARM/arm64 UEFI stub (Ard Biesheuvel)

   - Code deduplication work and various other cleanups (Lukas Wunner)

   - ... plus various other fixes and cleanups"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/libstub: Make file I/O chunking x86-specific
  efi: Print the secure boot status in x86 setup_arch()
  efi: Disable secure boot if shim is in insecure mode
  efi: Get and store the secure boot status
  efi: Add SHIM and image security database GUID definitions
  arm/efi: Allow invocation of arbitrary runtime services
  x86/efi: Allow invocation of arbitrary runtime services
  efi/libstub: Preserve .debug sections after absolute relocation check
  efi/x86: Add debug code to print cooked memmap
  efi/x86: Move the EFI BGRT init code to early init code
  efi: Use typed function pointers for the runtime services table
  efi/esrt: Fix typo in pr_err() message
  x86/efi: Add support for EFI_MEMORY_ATTRIBUTES_TABLE
  efi: Introduce the EFI_MEM_ATTR bit and set it from the memory attributes table
  efi: Make EFI_MEMORY_ATTRIBUTES_TABLE initialization common across all architectures
  x86/efi: Deduplicate efi_char16_printk()
  efi: Deduplicate efi_file_size() / _read() / _close()
2017-02-20 11:47:11 -08:00
Linus Torvalds f7458a5d63 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The RCU changes in this cycle are:

   - Dynticks updates, consolidating open-coded counter accesses into a
     well-defined API

   - SRCU updates: Simplify algorithm, add formal verification

   - Documentation updates

   - Miscellaneous fixes

   - Torture-test updates

  Most of the diffstat comes from the relatively large documentation
  update"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
  srcu: Reduce probability of SRCU ->unlock_count[] counter overflow
  rcutorture: Add CBMC-based formal verification for SRCU
  srcu: Force full grace-period ordering
  srcu: Implement more-efficient reader counts
  rcu: Adjust FQS offline checks for exact online-CPU detection
  rcu: Check cond_resched_rcu_qs() state less often to reduce GP overhead
  rcu: Abstract extended quiescent state determination
  rcu: Abstract dynticks extended quiescent state enter/exit operations
  rcu: Add lockdep checks to synchronous expedited primitives
  rcu: Eliminate unused expedited_normal counter
  llist: Clarify comments about when locking is needed
  rcu: Fix comment in rcu_organize_nocb_kthreads()
  rcu: Enable RCU tracepoints by default to aid in debugging
  rcu: Make rcu_cpu_starting() use its "cpu" argument
  rcu: Add comment headers to expedited-grace-period counter functions
  rcu: Don't wake rcuc/X kthreads on NOCB CPUs
  rcu: Re-enable TASKS_RCU for User Mode Linux
  rcu: Once again use NMI-based stack traces in stall warnings
  rcu: Remove short-term CPU kicking
  rcu: Add long-term CPU kicking
  ...
2017-02-20 11:21:17 -08:00
Matthew Wilcox 0a835c4f09 Reimplement IDR and IDA using the radix tree
The IDR is very similar to the radix tree.  It has some functionality that
the radix tree did not have (alloc next free, cyclic allocation, a
callback-based for_each, destroy tree), which is readily implementable on
top of the radix tree.  A few small changes were needed in order to use a
tag to represent nodes with free space below them.  More extensive
changes were needed to support storing NULL as a valid entry in an IDR.
Plain radix trees still interpret NULL as a not-present entry.

The IDA is reimplemented as a client of the newly enhanced radix tree.  As
in the current implementation, it uses a bitmap at the last level of the
tree.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2017-02-13 21:44:01 -05:00
Paul Gortmaker 8a293be0d6 core: migrate exception table users off module.h and onto extable.h
These files were including module.h for exception table related
functions.  We've now separated that content out into its own file
"extable.h" so now move over to that and where possible, avoid all
the extra header content in module.h that we don't really need to
compile these non-modular files.

Note:
   init/main.c still needs module.h for __init_or_module
   kernel/extable.c still needs module.h for is_module_text_address

...and so we don't get the benefit of removing module.h from the cpp
feed for these two files, unlike the almost universal 1:1 exchange
of module.h for extable.h we were able to do in the arch dirs.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Jessica Yu <jeyu@redhat.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2017-02-09 16:38:53 -05:00
Sergey Senozhatsky f92bac3b14 printk: rename nmi.c and exported api
A preparation patch for printk_safe work. No functional change.
- rename nmi.c to print_safe.c
- add `printk_safe' prefix to some (which used both by printk-safe
  and printk-nmi) of the exported functions.

Link: http://lkml.kernel.org/r/20161227141611.940-3-sergey.senozhatsky@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Calvin Owens <calvinowens@fb.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2017-02-08 11:02:33 +01:00
Laura Abbott 0f5bf6d0af arch: Rename CONFIG_DEBUG_RODATA and CONFIG_DEBUG_MODULE_RONX
Both of these options are poorly named. The features they provide are
necessary for system security and should not be considered debug only.
Change the names to CONFIG_STRICT_KERNEL_RWX and
CONFIG_STRICT_MODULE_RWX to better describe what these options do.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Jessica Yu <jeyu@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2017-02-07 12:32:52 -08:00
Ingo Molnar 87a8d03266 Linux 4.10-rc7
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Merge tag 'v4.10-rc7' into efi/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-07 08:49:17 +01:00
Greg Kroah-Hartman 17fa87fe5a Merge 4.10-rc7 into char-misc-next
We want the hv and other fixes in here as well to handle merge and
testing issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-06 09:39:13 +01:00
Ard Biesheuvel 56067812d5 kbuild: modversions: add infrastructure for emitting relative CRCs
This add the kbuild infrastructure that will allow architectures to emit
vmlinux symbol CRCs as 32-bit offsets to another location in the kernel
where the actual value is stored. This works around problems with CRCs
being mistaken for relocatable symbols on kernels that self relocate at
runtime (i.e., powerpc with CONFIG_RELOCATABLE=y)

For the kbuild side of things, this comes down to the following:

 - introducing a Kconfig symbol MODULE_REL_CRCS

 - adding a -R switch to genksyms to instruct it to emit the CRC symbols
   as references into the .rodata section

 - making modpost distinguish such references from absolute CRC symbols
   by the section index (SHN_ABS)

 - making kallsyms disregard non-absolute symbols with a __crc_ prefix

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-03 08:28:25 -08:00
Dave Young 7b0a911478 efi/x86: Move the EFI BGRT init code to early init code
Before invoking the arch specific handler, efi_mem_reserve() reserves
the given memory region through memblock.

efi_bgrt_init() will call efi_mem_reserve() after mm_init(), at which
time memblock is dead and should not be used anymore.

The EFI BGRT code depends on ACPI initialization to get the BGRT ACPI
table, so move parsing of the BGRT table to ACPI early boot code to
ensure that efi_mem_reserve() in EFI BGRT code still use memblock safely.

Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-acpi@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-9-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 08:45:46 +01:00
Ingo Molnar a8709fa4a0 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

 - Dynticks updates, consolidating open-coded counter accesses into a well-defined API

 - SRCU updates: Simplify algorithm, add formal verification

 - Documentation updates

 - Miscellaneous fixes

 - Torture-test updates

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-31 07:45:42 +01:00
Jason A. Donenfeld f5b98461cb random: use chacha20 for get_random_int/long
Now that our crng uses chacha20, we can rely on its speedy
characteristics for replacing MD5, while simultaneously achieving a
higher security guarantee. Before the idea was to use these functions if
you wanted random integers that aren't stupidly insecure but aren't
necessarily secure either, a vague gray zone, that hopefully was "good
enough" for its users. With chacha20, we can strengthen this claim,
since either we're using an rdrand-like instruction, or we're using the
same crng as /dev/urandom. And it's faster than what was before.

We could have chosen to replace this with a SipHash-derived function,
which might be slightly faster, but at the cost of having yet another
RNG construction in the kernel. By moving to chacha20, we have a single
RNG to analyze and verify, and we also already get good performance
improvements on all platforms.

Implementation-wise, rather than use a generic buffer for both
get_random_int/long and memcpy based on the size needs, we use a
specific buffer for 32-bit reads and for 64-bit reads. This way, we're
guaranteed to always have aligned accesses on all platforms. While
slightly more verbose in C, the assembly this generates is a lot
simpler than otherwise.

Finally, on 32-bit platforms where longs and ints are the same size,
we simply alias get_random_int to get_random_long.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Suggested-by: Theodore Ts'o <tytso@mit.edu>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-01-27 14:25:06 -05:00
Paul E. McKenney 1626c365f8 rcu: Re-enable TASKS_RCU for User Mode Linux
Now that User Mode Linux supports arch_irqs_disabled_flags(), this
commit re-enables TASKS_RCU for User Mode Linux.

Reported-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2017-01-23 11:37:12 -08:00
William Breathitt Gray ad90a3de9d pc104: Introduce the PC104 Kconfig option
PC/104 form factor devices serve a specific niche of embedded system
users; most Linux users will not have PC/104 form factor devices. This
patch introduces the PC104 Kconfig option, which should be used to
filter PC/104 specific device drivers and options, so that only those
users interested in PC/104 related options are exposed to them.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-19 12:42:25 +01:00
Sebastian Andrzej Siewior 7c6094db59 rcu: update: Make RCU_EXPEDITE_BOOT be the default
RCU_EXPEDITE_BOOT should speed up the boot process by enforcing
synchronize_rcu_expedited() instead of synchronize_rcu() during the boot
process. There should be no reason why one does not want this and there
is no need worry about real time latency at this point.
Therefore make it default.

Note that users wishing to avoid expediting entirely, for example when
bringing up new hardware possibly having flaky IPIs, can use the
rcu_normal boot parameter to override boot-time expediting.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ paulmck: Reworded commit log. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2017-01-16 16:56:39 -08:00
Peter Zijlstra 1e24edca05 locking/atomic, kref: Add KREF_INIT()
Since we need to change the implementation, stop exposing internals.

Provide KREF_INIT() to allow static initialization of struct kref.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:37:18 +01:00
Peter Zijlstra 9881b024b7 sched/clock: Delay switching sched_clock to stable
Currently we switch to the stable sched_clock if we guess the TSC is
usable, and then switch back to the unstable path if it turns out TSC
isn't stable during SMP bringup after all.

Delay switching to the stable path until after SMP bringup is
complete. This way we'll avoid switching during the time we detect the
worst of the TSC offences.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-14 11:29:59 +01:00
Arnd Bergmann 73b3514735 cgroup: move CONFIG_SOCK_CGROUP_DATA to init/Kconfig
We now 'select SOCK_CGROUP_DATA' but Kconfig complains that this is
not right when CONFIG_NET is disabled and there is no socket interface:

warning: (CGROUP_BPF) selects SOCK_CGROUP_DATA which has unmet direct dependencies (NET)

I don't know what the correct solution for this is, but simply removing
the dependency on NET from SOCK_CGROUP_DATA by moving it out of the
'if NET' section avoids the warning and does not produce other build
errors.

Fixes: 483c4933ea ("cgroup: Fix CGROUP_BPF config")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-11 09:47:10 -05:00
Parav Pandit 39d3e7584a rdmacg: Added rdma cgroup controller
Added rdma cgroup controller that does accounting, limit enforcement
on rdma/IB resources.

Added rdma cgroup header file which defines its APIs to perform
charging/uncharging functionality. It also defined APIs for RDMA/IB
stack for device registration. Devices which are registered will
participate in controller functions of accounting and limit
enforcements. It define rdmacg_device structure to bind IB stack
and RDMA cgroup controller.

RDMA resources are tracked using resource pool. Resource pool is per
device, per cgroup entity which allows setting up accounting limits
on per device basis.

Currently resources are defined by the RDMA cgroup.

Resource pool is created/destroyed dynamically whenever
charging/uncharging occurs respectively and whenever user
configuration is done. Its a tradeoff of memory vs little more code
space that creates resource pool object whenever necessary, instead of
creating them during cgroup creation and device registration time.

Signed-off-by: Parav Pandit <pandit.parav@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-01-10 11:14:27 -05:00
Nicholas Piggin 6290602709 mm: add PageWaiters indicating tasks are waiting for a page bit
Add a new page flag, PageWaiters, to indicate the page waitqueue has
tasks waiting. This can be tested rather than testing waitqueue_active
which requires another cacheline load.

This bit is always set when the page has tasks on page_waitqueue(page),
and is set and cleared under the waitqueue lock. It may be set when
there are no tasks on the waitqueue, which will cause a harmless extra
wakeup check that will clears the bit.

The generic bit-waitqueue infrastructure is no longer used for pages.
Instead, waitqueues are used directly with a custom key type. The
generic code was not flexible enough to have PageWaiters manipulation
under the waitqueue lock (which simplifies concurrency).

This improves the performance of page lock intensive microbenchmarks by
2-3%.

Putting two bits in the same word opens the opportunity to remove the
memory barrier between clearing the lock bit and testing the waiters
bit, after some work on the arch primitives (e.g., ensuring memory
operand widths match and cover both bits).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-25 11:54:48 -08:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Linus Torvalds 52f40e9d65 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes and cleanups from David Miller:

 1) Revert bogus nla_ok() change, from Alexey Dobriyan.

 2) Various bpf validator fixes from Daniel Borkmann.

 3) Add some necessary SET_NETDEV_DEV() calls to hsis_femac and hip04
    drivers, from Dongpo Li.

 4) Several ethtool ksettings conversions from Philippe Reynes.

 5) Fix bugs in inet port management wrt. soreuseport, from Tom Herbert.

 6) XDP support for virtio_net, from John Fastabend.

 7) Fix NAT handling within a vrf, from David Ahern.

 8) Endianness fixes in dpaa_eth driver, from Claudiu Manoil

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (63 commits)
  net: mv643xx_eth: fix build failure
  isdn: Constify some function parameters
  mlxsw: spectrum: Mark split ports as such
  cgroup: Fix CGROUP_BPF config
  qed: fix old-style function definition
  net: ipv6: check route protocol when deleting routes
  r6040: move spinlock in r6040_close as SOFTIRQ-unsafe lock order detected
  irda: w83977af_ir: cleanup an indent issue
  net: sfc: use new api ethtool_{get|set}_link_ksettings
  net: davicom: dm9000: use new api ethtool_{get|set}_link_ksettings
  net: cirrus: ep93xx: use new api ethtool_{get|set}_link_ksettings
  net: chelsio: cxgb3: use new api ethtool_{get|set}_link_ksettings
  net: chelsio: cxgb2: use new api ethtool_{get|set}_link_ksettings
  bpf: fix mark_reg_unknown_value for spilled regs on map value marking
  bpf: fix overflow in prog accounting
  bpf: dynamically allocate digest scratch buffer
  gtp: Fix initialization of Flags octet in GTPv1 header
  gtp: gtp_check_src_ms_ipv4() always return success
  net/x25: use designated initializers
  isdn: use designated initializers
  ...
2016-12-17 20:17:04 -08:00
Andy Lutomirski 483c4933ea cgroup: Fix CGROUP_BPF config
CGROUP_BPF depended on SOCK_CGROUP_DATA which can't be manually
enabled, making it rather challenging to turn CGROUP_BPF on.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-17 21:42:45 -05:00
Linus Torvalds 4d98ead183 Modules updates for v4.10
Summary of modules changes for the 4.10 merge window:
 
 * The rodata= cmdline parameter has been extended to additionally
   apply to module mappings
 
 * Fix a hard to hit race between module loader error/clean up
   handling and ftrace registration
 
 * Some code cleanups, notably panic.c and modules code use a
   unified taint_flags table now. This is much cleaner than
   duplicating the taint flag code in modules.c
 
 Signed-off-by: Jessica Yu <jeyu@redhat.com>
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Merge tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.10 merge window:

   - The rodata= cmdline parameter has been extended to additionally
     apply to module mappings

   - Fix a hard to hit race between module loader error/clean up
     handling and ftrace registration

   - Some code cleanups, notably panic.c and modules code use a unified
     taint_flags table now. This is much cleaner than duplicating the
     taint flag code in modules.c"

* tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: fix DEBUG_SET_MODULE_RONX typo
  module: extend 'rodata=off' boot cmdline parameter to module mappings
  module: Fix a comment above strong_try_module_get()
  module: When modifying a module's text ignore modules which are going away too
  module: Ensure a module's state is set accordingly during module coming cleanup code
  module: remove trailing whitespace
  taint/module: Clean up global and module taint flags handling
  modpost: free allocated memory
2016-12-14 20:12:43 -08:00
Linus Torvalds c11a6cfb01 Merge branch 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:
 "Mostly patches to initialize workqueue subsystem earlier and get rid
  of keventd_up().

  The patches were headed for the last merge cycle but got delayed due
  to a bug found late minute, which is fixed now.

  Also, to help debugging, destroy_workqueue() is more chatty now on a
  sanity check failure."

* 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: move wq_numa_init() to workqueue_init()
  workqueue: remove keventd_up()
  debugobj, workqueue: remove keventd_up() usage
  slab, workqueue: remove keventd_up() usage
  power, workqueue: remove keventd_up() usage
  tty, workqueue: remove keventd_up() usage
  mce, workqueue: remove keventd_up() usage
  workqueue: make workqueue available early during boot
  workqueue: dump workqueue state on sanity check failures in destroy_workqueue()
2016-12-13 12:59:57 -08:00
Linus Torvalds e7aa8c2eb1 These are the documentation changes for 4.10.
It's another busy cycle for the docs tree, as the sphinx conversion
 continues.  Highlights include:
 
  - Further work on PDF output, which remains a bit of a pain but should be
    more solid now.
 
  - Five more DocBook template files converted to Sphinx.  Only 27 to go...
    Lots of plain-text files have also been converted and integrated.
 
  - Images in binary formats have been replaced with more source-friendly
    versions.
 
  - Various bits of organizational work, including the renaming of various
    files discussed at the kernel summit.
 
  - New documentation for the device_link mechanism.
 
 ...and, of course, lots of typo fixes and small updates.
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Merge tag 'docs-4.10' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "These are the documentation changes for 4.10.

  It's another busy cycle for the docs tree, as the sphinx conversion
  continues. Highlights include:

   - Further work on PDF output, which remains a bit of a pain but
     should be more solid now.

   - Five more DocBook template files converted to Sphinx. Only 27 to
     go... Lots of plain-text files have also been converted and
     integrated.

   - Images in binary formats have been replaced with more
     source-friendly versions.

   - Various bits of organizational work, including the renaming of
     various files discussed at the kernel summit.

   - New documentation for the device_link mechanism.

  ... and, of course, lots of typo fixes and small updates"

* tag 'docs-4.10' of git://git.lwn.net/linux: (193 commits)
  dma-buf: Extract dma-buf.rst
  Update Documentation/00-INDEX
  docs: 00-INDEX: document directories/files with no docs
  docs: 00-INDEX: remove non-existing entries
  docs: 00-INDEX: add missing entries for documentation files/dirs
  docs: 00-INDEX: consolidate process/ and admin-guide/ description
  scripts: add a script to check if Documentation/00-INDEX is sane
  Docs: change sh -> awk in REPORTING-BUGS
  Documentation/core-api/device_link: Add initial documentation
  core-api: remove an unexpected unident
  ppc/idle: Add documentation for powersave=off
  Doc: Correct typo, "Introdution" => "Introduction"
  Documentation/atomic_ops.txt: convert to ReST markup
  Documentation/local_ops.txt: convert to ReST markup
  Documentation/assoc_array.txt: convert to ReST markup
  docs-rst: parse-headers.pl: cleanup the documentation
  docs-rst: fix media cleandocs target
  docs-rst: media/Makefile: reorganize the rules
  docs-rst: media: build SVG from graphviz files
  docs-rst: replace bayer.png by a SVG image
  ...
2016-12-12 21:58:13 -08:00
Linus Torvalds e34bac726d Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - various misc bits

 - most of MM (quite a lot of MM material is awaiting the merge of
   linux-next dependencies)

 - kasan

 - printk updates

 - procfs updates

 - MAINTAINERS

 - /lib updates

 - checkpatch updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (123 commits)
  init: reduce rootwait polling interval time to 5ms
  binfmt_elf: use vmalloc() for allocation of vma_filesz
  checkpatch: don't emit unified-diff error for rename-only patches
  checkpatch: don't check c99 types like uint8_t under tools
  checkpatch: avoid multiple line dereferences
  checkpatch: don't check .pl files, improve absolute path commit log test
  scripts/checkpatch.pl: fix spelling
  checkpatch: don't try to get maintained status when --no-tree is given
  lib/ida: document locking requirements a bit better
  lib/rbtree.c: fix typo in comment of ____rb_erase_color
  lib/Kconfig.debug: make CONFIG_STRICT_DEVMEM depend on CONFIG_DEVMEM
  MAINTAINERS: add drm and drm/i915 irc channels
  MAINTAINERS: add "C:" for URI for chat where developers hang out
  MAINTAINERS: add drm and drm/i915 bug filing info
  MAINTAINERS: add "B:" for URI where to file bugs
  get_maintainer: look for arbitrary letter prefixes in sections
  printk: add Kconfig option to set default console loglevel
  printk/sound: handle more message headers
  printk/btrfs: handle more message headers
  printk/kdb: handle more message headers
  ...
2016-12-12 20:50:02 -08:00
Linus Torvalds 9465d9cc31 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The time/timekeeping/timer folks deliver with this update:

   - Fix a reintroduced signed/unsigned issue and cleanup the whole
     signed/unsigned mess in the timekeeping core so this wont happen
     accidentaly again.

   - Add a new trace clock based on boot time

   - Prevent injection of random sleep times when PM tracing abuses the
     RTC for storage

   - Make posix timers configurable for real tiny systems

   - Add tracepoints for the alarm timer subsystem so timer based
     suspend wakeups can be instrumented

   - The usual pile of fixes and updates to core and drivers"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  timekeeping: Use mul_u64_u32_shr() instead of open coding it
  timekeeping: Get rid of pointless typecasts
  timekeeping: Make the conversion call chain consistently unsigned
  timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion
  alarmtimer: Add tracepoints for alarm timers
  trace: Update documentation for mono, mono_raw and boot clock
  trace: Add an option for boot clock as trace clock
  timekeeping: Add a fast and NMI safe boot clock
  timekeeping/clocksource_cyc2ns: Document intended range limitation
  timekeeping: Ignore the bogus sleep time if pm_trace is enabled
  selftests/timers: Fix spelling mistake "Asyncrhonous" -> "Asynchronous"
  clocksource/drivers/bcm2835_timer: Unmap region obtained by of_iomap
  clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map()
  arm64: dts: rockchip: Arch counter doesn't tick in system suspend
  clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend
  posix-timers: Make them configurable
  posix_cpu_timers: Move the add_device_randomness() call to a proper place
  timer: Move sys_alarm from timer.c to itimer.c
  ptp_clock: Allow for it to be optional
  Kconfig: Regenerate *.c_shipped files after previous changes
  ...
2016-12-12 19:56:15 -08:00
Jungseung Lee 39a0e975c3 init: reduce rootwait polling interval time to 5ms
For several devices, the rootwait time is sensitive because it directly
affects booting time.  The polling interval of rootwait is currently
100ms.  To save unnessesary waiting time, reduce the polling interval to
5 ms.

[akpm@linux-foundation.org: remove used-once #define]
Link: http://lkml.kernel.org/r/20161207060743.1728-1-js07.lee@samsung.com
Signed-off-by: Jungseung Lee <js07.lee@samsung.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:10 -08:00
Linus Torvalds 212f30008a Merge branch 'x86-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 idle updates from Ingo Molnar:
 "There were two bigger changes in this development cycle:

   - remove idle notifiers:

       32 files changed, 74 insertions(+), 803 deletions(-)

     These notifiers were of questionable value and the main usecase,
     the i7300 driver, was essentially unmaintained and can be removed,
     plus modern power management concepts don't need the callback - so
     use this golden opportunity and get rid of this opaque and fragile
     callback from a latency sensitive code path.

     (Len Brown, Thomas Gleixner)

   - improve the AMD Erratum 400 workaround that used high overhead MSR
     polling in the idle loop (Borisla Petkov, Thomas Gleixner)"

* 'x86-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Remove empty idle.h header
  x86/amd: Simplify AMD E400 aware idle routine
  x86/amd: Check for the C1E bug post ACPI subsystem init
  x86/bugs: Separate AMD E400 erratum and C1E bug
  x86/cpufeature: Provide helper to set bugs bits
  x86/idle: Remove enter_idle(), exit_idle()
  x86: Remove x86_test_and_clear_bit_percpu()
  x86/idle: Remove is_idle flag
  x86/idle: Remove idle_notifier
  i7300_idle: Remove this driver
2016-12-12 14:55:04 -08:00
Thomas Gleixner e7ff3a4763 x86/amd: Check for the C1E bug post ACPI subsystem init
AMD CPUs affected by the E400 erratum suffer from the issue that the
local APIC timer stops when the CPU goes into C1E. Unfortunately there
is no way to detect the affected CPUs on early boot. It's only possible
to determine the range of possibly affected CPUs from the family/model
range.

The actual decision whether to enter C1E and thus cause the bug is done
by the firmware and we need to detect that case late, after ACPI has
been initialized.

The current solution is to check in the idle routine whether the CPU is
affected by reading the MSR_K8_INT_PENDING_MSG MSR and checking for the
K8_INTP_C1E_ACTIVE_MASK bits. If one of the bits is set then the CPU is
affected and the system is switched into forced broadcast mode.

This is ineffective and on non-affected CPUs every entry to idle does
the extra RDMSR.

After doing some research it turns out that the bits are visible on the
boot CPU right after the ACPI subsystem is initialized in the early
boot process. So instead of polling for the bits in the idle loop, add
a detection function after acpi_subsystem_init() and check for the MSR
bits. If set, then the X86_BUG_AMD_APIC_C1E is set on the boot CPU and
the TSC is marked unstable when X86_FEATURE_NONSTOP_TSC is not set as it
will stop in C1E state as well.

The switch to broadcast mode cannot be done at this point because the
boot CPU still uses HPET as a clockevent device and the local APIC timer
is not yet calibrated and installed. The switch to broadcast mode on the
affected CPUs needs to be done when the local APIC timer is actually set
up.

This allows to cleanup the amd_e400_idle() function in the next step.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20161209182912.2726-4-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 21:23:21 +01:00
David S. Miller 2745529ac7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Couple conflicts resolved here:

1) In the MACB driver, a bug fix to properly initialize the
   RX tail pointer properly overlapped with some changes
   to support variable sized rings.

2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix
   overlapping with a reorganization of the driver to support
   ACPI, OF, as well as PCI variants of the chip.

3) In 'net' we had several probe error path bug fixes to the
   stmmac driver, meanwhile a lot of this code was cleaned up
   and reorganized in 'net-next'.

4) The cls_flower classifier obtained a helper function in
   'net-next' called __fl_delete() and this overlapped with
   Daniel Borkamann's bug fix to use RCU for object destruction
   in 'net'.  It also overlapped with Jiri's change to guard
   the rhashtable_remove_fast() call with a check against
   tc_skip_sw().

5) In mlx4, a revert bug fix in 'net' overlapped with some
   unrelated changes in 'net-next'.

6) In geneve, a stale header pointer after pskb_expand_head()
   bug fix in 'net' overlapped with a large reorganization of
   the same code in 'net-next'.  Since the 'net-next' code no
   longer had the bug in question, there was nothing to do
   other than to simply take the 'net-next' hunks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 12:29:53 -05:00
Linus Torvalds faaae2a581 Re-enable CONFIG_MODVERSIONS in a slightly weaker form
This enables CONFIG_MODVERSIONS again, but allows for missing symbol CRC
information in order to work around the issue that newer binutils
versions seem to occasionally drop the CRC on the floor.  binutils 2.26
seems to work fine, while binutils 2.27 seems to break MODVERSIONS of
symbols that have been defined in assembler files.

[ We've had random missing CRC's before - it may be an old problem that
  just is now reliably triggered with the weak asm symbols and a new
  version of binutils ]

Some day I really do want to remove MODVERSIONS entirely.  Sadly, today
does not appear to be that day: Debian people apparently do want the
option to enable MODVERSIONS to make it easier to have external modules
across kernel versions, and this seems to be a fairly minimal fix for
the annoying problem.

Cc: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-29 16:01:30 -08:00
Arnd Bergmann 4d217a5adc module: fix DEBUG_SET_MODULE_RONX typo
The newly added 'rodata_enabled' global variable is protected by
the wrong #ifdef, leading to a link error when CONFIG_DEBUG_SET_MODULE_RONX
is turned on:

kernel/module.o: In function `disable_ro_nx':
module.c:(.text.unlikely.disable_ro_nx+0x88): undefined reference to `rodata_enabled'
kernel/module.o: In function `module_disable_ro':
module.c:(.text.module_disable_ro+0x8c): undefined reference to `rodata_enabled'
kernel/module.o: In function `module_enable_ro':
module.c:(.text.module_enable_ro+0xb0): undefined reference to `rodata_enabled'

CONFIG_SET_MODULE_RONX does not exist, so use the correct one instead.

Fixes: 39290b389e ("module: extend 'rodata=off' boot cmdline parameter to module mappings")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-28 11:37:57 -08:00
AKASHI Takahiro 39290b389e module: extend 'rodata=off' boot cmdline parameter to module mappings
The current "rodata=off" parameter disables read-only kernel mappings
under CONFIG_DEBUG_RODATA:
    commit d2aa1acad2 ("mm/init: Add 'rodata=off' boot cmdline parameter
    to disable read-only kernel mappings")

This patch is a logical extension to module mappings ie. read-only mappings
at module loading can be disabled even if CONFIG_DEBUG_SET_MODULE_RONX
(mainly for debug use). Please note, however, that it only affects RO/RW
permissions, keeping NX set.

This is the first step to make CONFIG_DEBUG_SET_MODULE_RONX mandatory
(always-on) in the future as CONFIG_DEBUG_RODATA on x86 and arm64.

Suggested-by: and Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Link: http://lkml.kernel.org/r/20161114061505.15238-1-takahiro.akashi@linaro.org
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-27 16:15:33 -08:00
David S. Miller 0b42f25d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.

Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-26 23:42:21 -05:00
Linus Torvalds cd3caefb46 Fix subtle CONFIG_MODVERSIONS problems
CONFIG_MODVERSIONS has been broken for pretty much the whole 4.9 series,
and quite frankly, nobody has cared very deeply.  We absolutely know how
to fix it, and it's not _complicated_, but it's not exactly pretty
either.

This oneliner fixes it without the ugliness, and allows for further
future cleanups.

  "We've secretly replaced their regular MODVERSIONS with nothing at
   all, let's see if they notice"

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-25 15:44:47 -08:00
Daniel Mack 3007098494 cgroup: add support for eBPF programs
This patch adds two sets of eBPF program pointers to struct cgroup.
One for such that are directly pinned to a cgroup, and one for such
that are effective for it.

To illustrate the logic behind that, assume the following example
cgroup hierarchy.

  A - B - C
        \ D - E

If only B has a program attached, it will be effective for B, C, D
and E. If D then attaches a program itself, that will be effective for
both D and E, and the program in B will only affect B and C. Only one
program of a given type is effective for a cgroup.

Attaching and detaching programs will be done through the bpf(2)
syscall. For now, ingress and egress inet socket filtering are the
only supported use-cases.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25 16:25:52 -05:00
Nicolas Schichan 18594e9bc4 init: use pr_cont() when displaying rotator during ramdisk loading.
Otherwise each individual rotator char would be printed in a new line:

(...)
[    0.642350] -
[    0.644374] |
[    0.646367] -
(...)

Signed-off-by: Nicolas Schichan <nicolas.schichan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-24 09:32:20 -08:00
Nicolas Pitre baa73d9e47 posix-timers: Make them configurable
Some embedded systems have no use for them.  This removes about
25KB from the kernel binary size when configured out.

Corresponding syscalls are routed to a stub logging the attempt to
use those syscalls which should be enough of a clue if they were
disabled without proper consideration. They are: timer_create,
timer_gettime: timer_getoverrun, timer_settime, timer_delete,
clock_adjtime, setitimer, getitimer, alarm.

The clock_settime, clock_gettime, clock_getres and clock_nanosleep
syscalls are replaced by simple wrappers compatible with CLOCK_REALTIME,
CLOCK_MONOTONIC and CLOCK_BOOTTIME only which should cover the vast
majority of use cases with very little code.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-7-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:35 +01:00
Mauro Carvalho Chehab 8c27ceff36 docs: fix locations of several documents that got moved
The previous patch renamed several files that are cross-referenced
along the Kernel documentation. Adjust the links to point to
the right places.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-10-24 08:12:35 -02:00
Tejun Heo 8bc4a04455 Merge branch 'for-4.9' into for-4.10 2016-10-19 12:12:40 -04:00
Linus Torvalds 9ffc66941d This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot time as
 possible, hoping to capitalize on any possible variation in CPU operation
 (due to runtime data differences, hardware differences, SMP ordering,
 thermal timing variation, cache behavior, etc).
 
 At the very least, this plugin is a much more comprehensive example for
 how to manipulate kernel code using the gcc plugin internals.
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Merge tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull gcc plugins update from Kees Cook:
 "This adds a new gcc plugin named "latent_entropy". It is designed to
  extract as much possible uncertainty from a running system at boot
  time as possible, hoping to capitalize on any possible variation in
  CPU operation (due to runtime data differences, hardware differences,
  SMP ordering, thermal timing variation, cache behavior, etc).

  At the very least, this plugin is a much more comprehensive example
  for how to manipulate kernel code using the gcc plugin internals"

* tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  latent_entropy: Mark functions with __latent_entropy
  gcc-plugins: Add latent_entropy plugin
2016-10-15 10:03:15 -07:00
Linus Torvalds 84d69848c9 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - EXPORT_SYMBOL for asm source by Al Viro.

   This does bring a regression, because genksyms no longer generates
   checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is
   working on a patch to fix this.

   Plus, we are talking about functions like strcpy(), which rarely
   change prototypes.

 - Fixes for PPC fallout of the above by Stephen Rothwell and Nick
   Piggin

 - fixdep speedup by Alexey Dobriyan.

 - preparatory work by Nick Piggin to allow architectures to build with
   -ffunction-sections, -fdata-sections and --gc-sections

 - CONFIG_THIN_ARCHIVES support by Stephen Rothwell

 - fix for filenames with colons in the initramfs source by me.

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits)
  initramfs: Escape colons in depfile
  ppc: there is no clear_pages to export
  powerpc/64: whitelist unresolved modversions CRCs
  kbuild: -ffunction-sections fix for archs with conflicting sections
  kbuild: add arch specific post-link Makefile
  kbuild: allow archs to select link dead code/data elimination
  kbuild: allow architectures to use thin archives instead of ld -r
  kbuild: Regenerate genksyms lexer
  kbuild: genksyms fix for typeof handling
  fixdep: faster CONFIG_ search
  ia64: move exports to definitions
  sparc32: debride memcpy.S a bit
  [sparc] unify 32bit and 64bit string.h
  sparc: move exports to definitions
  ppc: move exports to definitions
  arm: move exports to definitions
  s390: move exports to definitions
  m68k: move exports to definitions
  alpha: move exports to actual definitions
  x86: move exports to actual definitions
  ...
2016-10-14 14:26:58 -07:00
Peter Zijlstra 26b5679e43 relay: Use irq_work instead of plain timer for deferred wakeup
Relay avoids calling wake_up_interruptible() for doing the wakeup of
readers/consumers, waiting for the generation of new data, from the
context of a process which produced the data.  This is apparently done to
prevent the possibility of a deadlock in case Scheduler itself is is
generating data for the relay, after acquiring rq->lock.

The following patch used a timer (to be scheduled at next jiffy), for
delegating the wakeup to another context.
	commit 7c9cb38302
	Author: Tom Zanussi <zanussi@comcast.net>
	Date:   Wed May 9 02:34:01 2007 -0700

	relay: use plain timer instead of delayed work

	relay doesn't need to use schedule_delayed_work() for waking readers
	when a simple timer will do.

Scheduling a plain timer, at next jiffies boundary, to do the wakeup
causes a significant wakeup latency for the Userspace client, which makes
relay less suitable for the high-frequency low-payload use cases where the
data gets generated at a very high rate, like multiple sub buffers getting
filled within a milli second.  Moreover the timer is re-scheduled on every
newly produced sub buffer so the timer keeps getting pushed out if sub
buffers are filled in a very quick succession (less than a jiffy gap
between filling of 2 sub buffers).  As a result relay runs out of sub
buffers to store the new data.

By using irq_work it is ensured that wakeup of userspace client, blocked
in the poll call, is done at earliest (through self IPI or next timer
tick) enabling it to always consume the data in time.  Also this makes
relay consistent with printk & ring buffers (trace), as they too use
irq_work for deferred wake up of readers.

[arnd@arndb.de: select CONFIG_IRQ_WORK]
 Link: http://lkml.kernel.org/r/20160912154035.3222156-1-arnd@arndb.de
[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1472906487-1559-1-git-send-email-akash.goel@intel.com
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11 15:06:32 -07:00
Emese Revfy 38addce8b6 gcc-plugins: Add latent_entropy plugin
This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot time as
possible, hoping to capitalize on any possible variation in CPU operation
(due to runtime data differences, hardware differences, SMP ordering,
thermal timing variation, cache behavior, etc).

At the very least, this plugin is a much more comprehensive example for
how to manipulate kernel code using the gcc plugin internals.

The need for very-early boot entropy tends to be very architecture or
system design specific, so this plugin is more suited for those sorts
of special cases. The existing kernel RNG already attempts to extract
entropy from reliable runtime variation, but this plugin takes the idea to
a logical extreme by permuting a global variable based on any variation
in code execution (e.g. a different value (and permutation function)
is used to permute the global based on loop count, case statement,
if/then/else branching, etc).

To do this, the plugin starts by inserting a local variable in every
marked function. The plugin then adds logic so that the value of this
variable is modified by randomly chosen operations (add, xor and rol) and
random values (gcc generates separate static values for each location at
compile time and also injects the stack pointer at runtime). The resulting
value depends on the control flow path (e.g., loops and branches taken).

Before the function returns, the plugin mixes this local variable into
the latent_entropy global variable. The value of this global variable
is added to the kernel entropy pool in do_one_initcall() and _do_fork(),
though it does not credit any bytes of entropy to the pool; the contents
of the global are just used to mix the pool.

Additionally, the plugin can pre-initialize arrays with build-time
random contents, so that two different kernel builds running on identical
hardware will not have the same starting values.

Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message and code comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
2016-10-10 14:51:44 -07:00
Linus Torvalds 997b611baf Merge branch 'parisc-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:
 "Changes include:

   - Fix boot of 32bit SMP kernel (initial kernel mapping was too small)

   - Added hardened usercopy checks

   - Drop bootmem and switch to memblock and NO_BOOTMEM implementation

   - Drop the BROKEN_RODATA config option (and thus remove the relevant
     code from the generic headers and files because parisc was the last
     architecture which used this config option)

   - Improve segfault reporting by printing human readable error strings

   - Various smaller changes, e.g. dwarf debug support for assembly
     code, update comments regarding copy_user_page_asm, switch to
     kmalloc_array()"

* 'parisc-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Increase KERNEL_INITIAL_SIZE for 32-bit SMP kernels
  parisc: Drop bootmem and switch to memblock
  parisc: Add hardened usercopy feature
  parisc: Add cfi_startproc and cfi_endproc to assembly code
  parisc: Move hpmc stack into page aligned bss section
  parisc: Fix self-detected CPU stall warnings on Mako machines
  parisc: Report trap type as human readable string
  parisc: Update comment regarding implementation of copy_user_page_asm
  parisc: Use kmalloc_array() in add_system_map_addresses()
  parisc: Check return value of smp_boot_one_cpu()
  parisc: Drop BROKEN_RODATA config option
2016-10-07 20:50:37 -07:00
Helge Deller b5d5cf2b8a parisc: Drop BROKEN_RODATA config option
PARISC was the only architecture which selected the BROKEN_RODATA config
option. Drop it and remove the special handling from init.h as well.

Signed-off-by: Helge Deller <deller@gmx.de>
2016-09-20 18:02:35 +02:00
Tejun Heo 3347fa0928 workqueue: make workqueue available early during boot
Workqueue is currently initialized in an early init call; however,
there are cases where early boot code has to be split and reordered to
come after workqueue initialization or the same code path which makes
use of workqueues is used both before workqueue initailization and
after.  The latter cases have to gate workqueue usages with
keventd_up() tests, which is nasty and easy to get wrong.

Workqueue usages have become widespread and it'd be a lot more
convenient if it can be used very early from boot.  This patch splits
workqueue initialization into two steps.  workqueue_init_early() which
sets up the basic data structures so that workqueues can be created
and work items queued, and workqueue_init() which actually brings up
workqueues online and starts executing queued work items.  The former
step can be done very early during boot once memory allocation,
cpumasks and idr are initialized.  The latter right after kthreads
become available.

This allows work item queueing and canceling from very early boot
which is what most of these use cases want.

* As systemd_wq being initialized doesn't indicate that workqueue is
  fully online anymore, update keventd_up() to test wq_online instead.
  The follow-up patches will get rid of all its usages and the
  function itself.

* Flushing doesn't make sense before workqueue is fully initialized.
  The flush functions trigger WARN and return immediately before fully
  online.

* Work items are never in-flight before fully online.  Canceling can
  always succeed by skipping the flush step.

* Some code paths can no longer assume to be called with irq enabled
  as irq is disabled during early boot.  Use irqsave/restore
  operations instead.

v2: Watchdog init, which requires timer to be running, moved from
    workqueue_init_early() to workqueue_init().

Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/CA+55aFx0vPuMuxn00rBSM192n-Du5uxy+4AvKa0SBSOVJeuCGg@mail.gmail.com
2016-09-17 13:18:21 -04:00