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Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Pull dmi update from Jean Delvare:
"Mark all struct dmi_system_id instances const"
* 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
dmi: Mark all struct dmi_system_id instances const
Pull pin control fixes from Linus Walleij:
"This slew of fixes for pin control was noticed and patched up early,
so to get the annoyance out of the way for -rc1 it would make sense to
send them already.
- Fix a build include in the Uniphier driver to keep pace with
ongoing refactorings.
- Fix a slew of minor semantic and syntactic issues as well as
stricting up Kconfig for the new Spreadtrum driver.
- Fix the GPIO interrupt set-up on the Marvell 37xx Armada as fallout
for dynamically allocating irq descriptors from the core. (Also
tagged for stable.)
- Fix AMD register suspend/resume state spool/unspooling so that
wakeup works as it should. (Also tagged for stable.)"
* tag 'pinctrl-v4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl/amd: save pin registers over suspend/resume
pinctrl: armada-37xx: Fix gpio interrupt setup
pinctrl: sprd: fix off by one bugs
pinctrl: sprd: check for allocation failure
pinctrl: sprd: Restrict PINCTRL_SPRD to ARCH_SPRD or COMPILE_TEST
pinctrl: sprd: fix build errors and dependencies
pinctrl: sprd: make three local functions static
pinctrl: uniphier: include <linux/build_bug.h> instead of <linux/bug.h>
... and __initconst if applicable.
Based on similar work for an older kernel in the Grsecurity patch.
[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Merge misc fixes from Andrew Morton:
"A few leftovers"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm, page_owner: skip unnecessary stack_trace entries
arm64: stacktrace: avoid listing stacktrace functions in stacktrace
mm: treewide: remove GFP_TEMPORARY allocation flag
IB/mlx4: fix sprintf format warning
fscache: fix fscache_objlist_show format processing
lib/test_bitmap.c: use ULL suffix for 64-bit constants
procfs: remove unused variable
drivers/media/cec/cec-adap.c: fix build with gcc-4.4.4
idr: remove WARN_ON_ONCE() when trying to replace negative ID
The touchpad in the Asus laptop models X505BA/BP and X542BA/BP is
unresponsive after suspend/resume. The following error appears during
resume:
i2c_hid i2c-ELAN1300:00: failed to reset device.
The problem here is that i2c_hid does not notice the interrupt being
generated at this point, because the GPIO is no longer configured
for interrupts.
Fix this by saving pinctrl-amd pin registers during suspend and
restoring them at resume time.
Based on code from pinctrl-intel.
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Pull perf fixes from Ingo Molnar:
"A handful of tooling fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf stat: Wait for the correct child
perf tools: Support running perf binaries with a dash in their name
perf config: Check not only section->from_system_config but also item's
perf ui progress: Fix progress update
perf ui progress: Make sure we always define step value
perf tools: Open perf.data with O_CLOEXEC flag
tools lib api: Fix make DEBUG=1 build
perf tests: Fix compile when libunwind's unwind.h is available
tools include linux: Guard against redefinition of some macros
Now that we have added breaks in the wait queue scan and allow bookmark
on scan position, we put this logic in the wake_up_page_bit function.
We can have very long page wait list in large system where multiple
pages share the same wait list. We break the wake up walk here to allow
other cpus a chance to access the list, and not to disable the interrupts
when traversing the list for too long. This reduces the interrupt and
rescheduling latency, and excessive page wait queue lock hold time.
[ v2: Remove bookmark_wake_function ]
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The page_owner stacktrace always begin as follows:
[<ffffff987bfd48f4>] save_stack+0x40/0xc8
[<ffffff987bfd4da8>] __set_page_owner+0x3c/0x6c
These two entries do not provide any useful information and limits the
available stacktrace depth. The page_owner stacktrace was skipping
caller function from stack entries but this was missed with commit
f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace")
Example page_owner entry after the patch:
Page allocated via order 0, mask 0x8(ffffff80085fb714)
PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0)
[<ffffff9b64989c14>] post_alloc_hook+0x70/0x80
...
[<ffffff9b651216e8>] msm_comm_try_state+0x5f8/0x14f4
[<ffffff9b6512486c>] msm_vidc_open+0x5e4/0x7d0
[<ffffff9b65113674>] msm_v4l2_open+0xa8/0x224
Link: http://lkml.kernel.org/r/1504078343-28754-2-git-send-email-guptap@codeaurora.org
Fixes: f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace")
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit dc749a09ea5e ("gpiolib: allow gpio irqchip to map irqs
dynamically"), the irqs for gpio are not statically allocated during in
gpiochip_irqchip_add.
This driver was based on this assumption for initializing the mask
associated to each interrupt this led to a NULL pointer crash in the
kernel:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
Mem abort info:
Exception class = DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000068
CM = 0, WnR = 1
[0000000000000000] user address but active_mm is swapper
Internal error: Oops: 96000044 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-06657-g3b9f8ed25dbe #576
Hardware name: Marvell Armada 3720 Development Board DB-88F3720-DDR3 (DT)
task: ffff80001d908000 task.stack: ffff000008068000
PC is at armada_37xx_pinctrl_probe+0x5f8/0x670
LR is at armada_37xx_pinctrl_probe+0x5e8/0x670
pc : [<ffff000008e25cdc>] lr : [<ffff000008e25ccc>] pstate: 60000045
sp : ffff00000806bb80
x29: ffff00000806bb80 x28: 0000000000000024
x27: 000000000000000c x26: 0000000000000001
x25: ffff80001efee760 x24: 0000000000000000
x23: ffff80001db6f570 x22: ffff80001db6f438
x21: 0000000000000000 x20: ffff80001d9f4810
x19: ffff80001db6f418 x18: 0000000000000000
x17: 0000000000000001 x16: 0000000000000019
x15: ffffffffffffffff x14: 0140000000000000
x13: 0000000000000000 x12: 0000000000000030
x11: 0101010101010101 x10: 0000000000000040
x9 : ffff000009923580 x8 : ffff80001d400248
x7 : ffff80001d400270 x6 : 0000000000000000
x5 : ffff80001d400248 x4 : ffff80001d400270
x3 : 0000000000000000 x2 : 0000000000000001
x1 : 0000000000000001 x0 : 0000000000000000
Process swapper/0 (pid: 1, stack limit = 0xffff000008068000)
Call trace:
Exception stack(0xffff00000806ba40 to 0xffff00000806bb80)
ba40: 0000000000000000 0000000000000001 0000000000000001 0000000000000000
ba60: ffff80001d400270 ffff80001d400248 0000000000000000 ffff80001d400270
ba80: ffff80001d400248 ffff000009923580 0000000000000040 0101010101010101
baa0: 0000000000000030 0000000000000000 0140000000000000 ffffffffffffffff
bac0: 0000000000000019 0000000000000001 0000000000000000 ffff80001db6f418
bae0: ffff80001d9f4810 0000000000000000 ffff80001db6f438 ffff80001db6f570
bb00: 0000000000000000 ffff80001efee760 0000000000000001 000000000000000c
bb20: 0000000000000024 ffff00000806bb80 ffff000008e25ccc ffff00000806bb80
bb40: ffff000008e25cdc 0000000060000045 ffff00000806bb60 ffff0000081189b8
bb60: ffffffffffffffff ffff00000811cf1c ffff00000806bb80 ffff000008e25cdc
[<ffff000008e25cdc>] armada_37xx_pinctrl_probe+0x5f8/0x670
[<ffff00000859d8c8>] platform_drv_probe+0x58/0xb8
[<ffff00000859bb44>] driver_probe_device+0x22c/0x2d8
[<ffff00000859bcac>] __driver_attach+0xbc/0xc0
[<ffff000008599c84>] bus_for_each_dev+0x4c/0x98
[<ffff00000859b440>] driver_attach+0x20/0x28
[<ffff00000859af90>] bus_add_driver+0x1b8/0x228
[<ffff00000859c648>] driver_register+0x60/0xf8
[<ffff00000859df64>] __platform_driver_probe+0x74/0x130
[<ffff000008e256dc>] armada_37xx_pinctrl_driver_init+0x20/0x28
[<ffff000008083980>] do_one_initcall+0x38/0x128
[<ffff000008e00cf4>] kernel_init_freeable+0x188/0x22c
[<ffff0000089b56e8>] kernel_init+0x10/0x100
[<ffff000008084bb0>] ret_from_fork+0x10/0x18
Code: f9403fa2 12001341 1100075a 9ac12041 (b9000001)
---[ end trace 8b0f4e05e1603208 ]---
This patch moves the initialization of the mask field in the irq_startup
function. However some callbacks such as irq_set_type and irq_set_wake
could be called before irq_startup. For those functions the mask is
computed at each call which is not a issue as these functions are not
located in a hot path but are used sporadically for configuration.
Fixes: dc749a09ea5e ("gpiolib: allow gpio irqchip to map irqs
dynamically")
Cc: <stable@vger.kernel.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Pull scheduler fixes from Ingo Molnar:
"Three CPU hotplug related fixes and a debugging improvement"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/debug: Add debugfs knob for "sched_debug"
sched/core: WARN() when migrating to an offline CPU
sched/fair: Plug hole between hotplug and active_load_balance()
sched/fair: Avoid newidle balance for !active CPUs
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
- Fix TUI progress bar when delta from new total from that of the
previous update is greater than the progress "step" (screen width
progress bar block)) (Jiri Olsa)
- Make tools/lib/api make DEBUG=1 build use -D_FORTIFY_SOURCE=2 not
to cripple debuginfo, just like tools/perf/ does (Jiri Olsa)
- Avoid leaking the 'perf.data' file to workloads started from the
'perf record' command line by using the O_CLOEXEC open flag (Jiri Olsa)
- Fix building when libunwind's 'unwind.h' file is present in the
include path, clashing with tools/perf/util/unwind.h (Milian Wolff)
- Check per .perfconfig section entry flag, not just per section (Taeung Song)
- Support running perf binaries with a dash in their name, needed to
run perf as an AppImage (Milian Wolff)
- Wait for the right child by using waitpid() when running workloads
from 'perf stat', also to fix using perf as an AppImage (Milian Wolff)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We encountered workloads that have very long wake up list on large
systems. A waker takes a long time to traverse the entire wake list and
execute all the wake functions.
We saw page wait list that are up to 3700+ entries long in tests of
large 4 and 8 socket systems. It took 0.8 sec to traverse such list
during wake up. Any other CPU that contends for the list spin lock will
spin for a long time. It is a result of the numa balancing migration of
hot pages that are shared by many threads.
Multiple CPUs waking are queued up behind the lock, and the last one
queued has to wait until all CPUs did all the wakeups.
The page wait list is traversed with interrupt disabled, which caused
various problems. This was the original cause that triggered the NMI
watch dog timer in: https://patchwork.kernel.org/patch/9800303/ . Only
extending the NMI watch dog timer there helped.
This patch bookmarks the waker's scan position in wake list and break
the wake up walk, to allow access to the list before the waker resume
its walk down the rest of the wait list. It lowers the interrupt and
rescheduling latency.
This patch also provides a performance boost when combined with the next
patch to break up page wakeup list walk. We saw 22% improvement in the
will-it-scale file pread2 test on a Xeon Phi system running 256 threads.
[ v2: Merged in Linus' changes to remove the bookmark_wake_function, and
simply access to flags. ]
Reported-by: Kan Liang <kan.liang@intel.com>
Tested-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The stacktraces always begin as follows:
[<c00117b4>] save_stack_trace_tsk+0x0/0x98
[<c0011870>] save_stack_trace+0x24/0x28
...
This is because the stack trace code includes the stack frames for
itself. This is incorrect behaviour, and also leads to "skip" doing the
wrong thing (which is the number of stack frames to avoid recording.)
Perversely, it does the right thing when passed a non-current thread.
Fix this by ensuring that we have a known constant number of frames
above the main stack trace function, and always skip these.
This was fixed for arch arm by commit 3683f44c42e9 ("ARM: stacktrace:
avoid listing stacktrace functions in stacktrace")
Link: http://lkml.kernel.org/r/1504078343-28754-1-git-send-email-guptap@codeaurora.org
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
info->groups[] has info->ngroups elements so these comparisons should be
>= instead of >.
Fixes: 41d32cfce1ae ("pinctrl: sprd: Add Spreadtrum pin control driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Baolin Wang <baolin.wang@spreadtrum.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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