Pull drm updates from Dave Airlie:
"This is the main drm pull, it has a shared branch with some alsa
crossover but everything should be acked by relevant people.
New drivers:
- ATMEL HLCDC driver
- designware HDMI core support (used in multiple SoCs).
core:
- lots more atomic modesetting work, properties and atomic ioctl
(hidden under option)
- bridge rework allows support for Samsung exynos chromebooks to
work finally.
- some more panels supported
i915:
- atomic plane update support
- DSI uses shared DSI infrastructure
- Skylake basic support is all merged now
- component framework used for i915/snd-hda interactions
- write-combine cpu memory mappings
- engine init code refactored
- full ppgtt enabled where execlists are enabled.
- cherryview rps/gpu turbo and pipe CRC support.
radeon:
- indirect draw support for evergreen/cayman
- SMC and manual fan control for SI/CI
- Displayport audio support
amdkfd:
- SDMA usermode queue support
- replace suballocator usage with more suitable one
- rework for allowing interfacing to more than radeon
nouveau:
- major renaming in prep for later splitting work
- merge arm platform driver into nouveau
- GK20A reclocking support
msm:
- conversion to atomic modesetting
- YUV support for mdp4/5
- eDP support
- hw cursor for mdp5
tegra:
- conversion to atomic modesetting
- better suspend/resume support for child devices
rcar-du:
- interlaced support
imx:
- move to using dw_hdmi shared support
- mode_fixup support
sti:
- DVO support
- HDMI infoframe support
exynos:
- refactoring and cleanup, removed lots of internal unnecessary
abstraction
- exynos7 DECON display controller support
Along with the usual bunch of fixes, cleanups etc"
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (724 commits)
drm/radeon: fix voltage setup on hawaii
drm/radeon/dp: Set EDP_CONFIGURATION_SET for bridge chips if necessary
drm/radeon: only enable kv/kb dpm interrupts once v3
drm/radeon: workaround for CP HW bug on CIK
drm/radeon: Don't try to enable write-combining without PAT
drm/radeon: use 0-255 rather than 0-100 for pwm fan range
drm/i915: Clamp efficient frequency to valid range
drm/i915: Really ignore long HPD pulses on eDP
drm/exynos: Add DECON driver
drm/i915: Correct the base value while updating LP_OUTPUT_HOLD in MIPI_PORT_CTRL
drm/i915: Insert a command barrier on BLT/BSD cache flushes
drm/i915: Drop vblank wait from intel_dp_link_down
drm/exynos: fix NULL pointer reference
drm/exynos: remove exynos_plane_dpms
drm/exynos: remove mode property of exynos crtc
drm/exynos: Remove exynos_plane_dpms() call with no effect
drm/i915: Squelch overzealous uncore reset WARN_ON
drm/i915: Take runtime pm reference on hangcheck_info
drm/i915: Correct the IOSF Dev_FN field for IOSF transfers
drm/exynos: fix DMA_ATTR_NO_KERNEL_MAPPING usage
...
Pull clocksource updates from Ingo Molnar:
"The main change in this tree is the addition of various new SoC
clocksource/clockevents drivers: Conexant Digicolor SoCs, rockchip
rk3288 board, asm9260 for MIPS and versatile AB/PB boards"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
dts: versatile: Add sysregs node
clocksource: versatile: Adapt for Versatile AB and PB boards
dt/bindings: Add binding for Versatile system registers
clocksource: Driver for Conexant Digicolor SoC timer
clocksource: devicetree: Document Conexant Digicolor timer binding
clockevents: rockchip: Add rockchip timer for rk3288
ARM: clocksource: Add asm9260_timer driver
clocksource: marco: Rename marco to atlas7
clocksource: sirf: Remove unused variable
Pull irqchip updates from Ingo Molnar:
"Various irqchip driver updates, plus a genirq core update that allows
the initial spreading of irqs amonst CPUs without having to do it from
user-space"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Fix null pointer reference in irq_set_affinity_hint()
irqchip: gic: Allow interrupt level to be set for PPIs
irqchip: mips-gic: Handle pending interrupts once in __gic_irq_dispatch()
irqchip: Conexant CX92755 interrupts controller driver
irqchip: Devicetree: document Conexant Digicolor irq binding
irqchip: omap-intc: Remove unused legacy interface for omap2
irqchip: omap-intc: Fix support for dm814 and dm816
irqchip: mtk-sysirq: Get irq number from register resource size
irqchip: renesas-intc-irqpin: r8a7779 IRLM setup support
genirq: Set initial affinity in irq_set_affinity_hint()
The movement of the I2O tree into staging broke the DocBook build. Rather
than redirect the i2o references into staging, it seems better to just
remove them since this code is on its way out anyway.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Make it possible to disable offloading writes by setting the optional
'submit_from_crypt_cpus' table argument.
There are some situations where offloading write bios from the
encryption threads to a single thread degrades performance
significantly.
The default is to offload write bios to the same thread because it
benefits CFQ to have writes submitted using the same IO context.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use unbound workqueue by default so that work is automatically balanced
between available CPUs. The original behavior of encrypting using the
same cpu that IO was submitted on can still be enabled by setting the
optional 'same_cpu_crypt' table argument.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This patch move all packet info from driver source code to documentation
and adds info about v6 packet format (from driver source code).
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Pull tty/serial driver patches from Greg KH:
"Here's the big tty/serial driver update for 3.20-rc1. Nothing huge
here, just lots of driver updates and some core tty layer fixes as
well. All have been in linux-next with no reported issues"
* tag 'tty-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits)
serial: 8250: Fix UART_BUG_TXEN workaround
serial: driver for ETRAX FS UART
tty: remove unused variable sprop
serial: of-serial: fetch line number from DT
serial: samsung: earlycon support depends on CONFIG_SERIAL_SAMSUNG_CONSOLE
tty/serial: serial8250_set_divisor() can be static
tty/serial: Add Spreadtrum sc9836-uart driver support
Documentation: DT: Add bindings for Spreadtrum SoC Platform
serial: samsung: remove redundant interrupt enabling
tty: Remove external interface for tty_set_termios()
serial: omap: Fix RTS handling
serial: 8250_omap: Use UPSTAT_AUTORTS for RTS handling
serial: core: Rework hw-assisted flow control support
tty/serial: 8250_early: Add support for PXA UARTs
tty/serial: of_serial: add support for PXA/MMP uarts
tty/serial: of_serial: add DT alias ID handling
serial: 8250: Prevent concurrent updates to shadow registers
serial: 8250: Use canary to restart console after suspend
serial: 8250: Refactor XR17V35X divisor calculation
serial: 8250: Refactor divisor programming
...
Pull staging drivers patches from Greg KH:
"Here's the big staging driver tree update for 3.20-rc1.
Lots of little things in here, adding up to lots of overall cleanups.
The IIO driver updates are also in here as they cross the staging tree
boundry a lot. I2O has moved into staging as well, as a plan to drop
it from the tree eventually as that's a dead subsystem.
All of this has been in linux-next with no reported issues for a
while"
* tag 'staging-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (740 commits)
staging: lustre: lustre: libcfs: define symbols as static
staging: rtl8712: Do coding style cleanup
staging: lustre: make obd_updatemax_lock static
staging: rtl8188eu: core: switch with redundant cases
staging: rtl8188eu: odm: conditional setting with no effect
staging: rtl8188eu: odm: condition with no effect
staging: ft1000: fix braces warning
staging: sm7xxfb: fix remaining CamelCase
staging: sm7xxfb: fix CamelCase
staging: rtl8723au: multiple condition with no effect - if identical to else
staging: sm7xxfb: make smtc_scr_info static
staging/lustre/mdc: Initialize req in mdc_enqueue for !it case
staging/lustre/clio: Do not allow group locks with gid 0
staging/lustre/llite: don't add to page cache upon failure
staging/lustre/llite: Add exception entry check after radix_tree
staging/lustre/libcfs: protect kkuc_groups from write access
staging/lustre/fld: refer to MDT0 for fld lookup in some cases
staging/lustre/llite: Solve a race to access lli_has_smd in read case
staging/lustre/ptlrpc: hold rq_lock when modify rq_flags
staging/lustre/lnet: portal spreading rotor should be unsigned
...
Pull char / misc patches from Greg KH:
"Here's the big char/misc driver update for 3.20-rc1.
Lots of little things in here, all described in the changelog.
Nothing major or unusual, except maybe the binder selinux stuff, which
was all acked by the proper selinux people and they thought it best to
come through this tree.
All of this has been in linux-next with no reported issues for a while"
* tag 'char-misc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (90 commits)
coresight: fix function etm_writel_cp14() parameter order
coresight-etm: remove check for unknown Kconfig macro
coresight: fixing CPU hwid lookup in device tree
coresight: remove the unnecessary function coresight_is_bit_set()
coresight: fix the debug AMBA bus name
coresight: remove the extra spaces
coresight: fix the link between orphan connection and newly added device
coresight: remove the unnecessary replicator property
coresight: fix the replicator subtype value
pdfdocs: Fix 'make pdfdocs' failure for 'uio-howto.tmpl'
mcb: Fix error path of mcb_pci_probe
virtio/console: verify device has config space
ti-st: clean up data types (fix harmless memory corruption)
mei: me: release hw from reset only during the reset flow
mei: mask interrupt set bit on clean reset bit
extcon: max77693: Constify struct regmap_config
extcon: adc-jack: Release IIO channel on driver remove
extcon: Remove duplicated include from extcon-class.c
Drivers: hv: vmbus: hv_process_timer_expiration() can be static
Drivers: hv: vmbus: serialize Offer and Rescind offer
...
Pull USB patches from Greg KH:
"Here's the big pull request for the USB driver tree for 3.20-rc1.
Nothing major happening here, just lots of gadget driver updates, new
device ids, and a bunch of cleanups.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (299 commits)
usb: musb: fix device hotplug behind hub
usb: dwc2: Fix a bug in reading the endpoint directions from reg.
staging: emxx_udc: fix the build error
usb: Retry port status check on resume to work around RH bugs
Revert "usb: Reset USB-3 devices on USB-3 link bounce"
uhci-hub: use HUB_CHAR_*
usb: kconfig: replace PPC_OF with PPC
ehci-pci: disable for Intel MID platforms (update)
usb: gadget: Kconfig: use bool instead of boolean
usb: musb: blackfin: remove incorrect __exit_p()
USB: fix use-after-free bug in usb_hcd_unlink_urb()
ehci-pci: disable for Intel MID platforms
usb: host: pci_quirks: joing string literals
USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd)
USB: usbfs: allow URBs to be reaped after disconnection
cdc-acm: kill unnecessary messages
cdc-acm: add sanity checks
usb: phy: phy-generic: Fix USB PHY gpio reset
usb: dwc2: fix USB core dependencies
usb: renesas_usbhs: fix NULL pointer dereference in dma_release_channel()
...
This series adds support for Abracon AB-RTCMC-32.768kHz-B5ZE-S3 I2C RTC
chip. Unlike many RTC chips, it includes an internal oscillator which
spares room on the PCB. It also has some interesting features, like
battery low detection (which the driver in this series supports). The
only small "limitation" (mainly due to what RTC subsystem expects from
RTC chips) is the fact that its alarm is accurate to the second. This
series provides a solution (described below) for that limitation using
another mechanism of the chip.
I decided to split support between three different patches for
this v0:
- Patch 1/3: it simply references Abracon Corporation in vendor-prefixes
documentation file. As Abracon has no NASDAQ ticker symbol; I have
decided to use "abcn" (I initially started my work w/ "ab" but later
changed for "abcn" which looked more meaningful)
- Patch 2/3: it adds initial support for the chip and provides the
ability to read/write time and also read/write alarm. As the alarm
the chip provides is accurate to the minute, the support provided
by this patch also has this limitation (e.g. UIE mode is not
supported).
- Patch 3/3: the chip supports a watchdog timer which can be used to
extend the alarm mechanism in patch 2/3 in order to provide support
for alarms under one minute (e.g. support UIE mode). In practice,
the logic I implemented is to use the watchdog timer for alarms which
are at most 4 minutes in the future and use the common alarm mechanism
for alarms which are set to larger values. With that additional patch
the device fully passes the rtctest.c program.
I decided to split the driver between two patches (2 and 3 of 3) in
order to ease review: patch 2 should be pretty straightforward to read
for someone familiar w/ RTC subsystem. Patch 3 only extends what is in
patch 2 regarding alarms.
This patch (of 3):
Documentation/devicetree/bindings/vendor-prefixes.txt: add vendor prefix
for Abracon Corporation
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Peter Huewe <peter.huewe@infineon.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robherring2@gmail.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Landley <rob@landley.net>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Kumar Gala <galak@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current in-tree users of ISL12057 RTC chip (NETGEAR ReadyNAS 102, 104 and
2120) do not have the IRQ#2 pin of the chip (associated w/ the Alarm1
mechanism) connected to their SoC, but to a PMIC (TPS65251 FWIW). This
specific hardware configuration allows the NAS to wake up when the alarms
rings.
Recently introduced alarm support for ISL12057 relies on the provision of
an "interrupts" property in system .dts file, which previous three users
will never get. For that reason, alarm support on those devices is not
function. To support this use case, this patch adds a new DT property for
ISL12057 (isil,irq2-can-wakeup-machine) to indicate that the chip is
capable of waking up the device using its IRQ#2 pin (even though it does
not have its IRQ#2 pin connected directly to the SoC).
This specific configuration was tested on a ReadyNAS 102 by setting an
alarm, powering off the device and see it reboot as expected when the
alarm rang w/:
# echo `date '+%s' -d '+ 1 minutes'` > /sys/class/rtc/rtc0/wakealarm
# shutdown -h now
As a side note, the ISL12057 remains in the list of trivial devices,
because the property is not per se required by the device to work but can
help handle system w/ specific requirements. In exchange, the new feature
is described in details in a specific documentation file.
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Peter Huewe <peter.huewe@infineon.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Darshana Padmadas <darshanapadmadas@gmail.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Landley <rob@landley.net>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This feature let us to detect accesses out of bounds of global variables.
This will work as for globals in kernel image, so for globals in modules.
Currently this won't work for symbols in user-specified sections (e.g.
__init, __read_mostly, ...)
The idea of this is simple. Compiler increases each global variable by
redzone size and add constructors invoking __asan_register_globals()
function. Information about global variable (address, size, size with
redzone ...) passed to __asan_register_globals() so we could poison
variable's redzone.
This patch also forces module_alloc() to return 8*PAGE_SIZE aligned
address making shadow memory handling (
kasan_module_alloc()/kasan_module_free() ) more simple. Such alignment
guarantees that each shadow page backing modules address space correspond
to only one module_alloc() allocation.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds arch specific code for kernel address sanitizer.
16TB of virtual addressed used for shadow memory. It's located in range
[ffffec0000000000 - fffffc0000000000] between vmemmap and %esp fixup
stacks.
At early stage we map whole shadow region with zero page. Latter, after
pages mapped to direct mapping address range we unmap zero pages from
corresponding shadow (see kasan_map_shadow()) and allocate and map a real
shadow memory reusing vmemmap_populate() function.
Also replace __pa with __pa_nodebug before shadow initialized. __pa with
CONFIG_DEBUG_VIRTUAL=y make external function call (__phys_addr)
__phys_addr is instrumented, so __asan_load could be called before shadow
area initialized.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kernel Address sanitizer (KASan) is a dynamic memory error detector. It
provides fast and comprehensive solution for finding use-after-free and
out-of-bounds bugs.
KASAN uses compile-time instrumentation for checking every memory access,
therefore GCC > v4.9.2 required. v4.9.2 almost works, but has issues with
putting symbol aliases into the wrong section, which breaks kasan
instrumentation of globals.
This patch only adds infrastructure for kernel address sanitizer. It's
not available for use yet. The idea and some code was borrowed from [1].
Basic idea:
The main idea of KASAN is to use shadow memory to record whether each byte
of memory is safe to access or not, and use compiler's instrumentation to
check the shadow memory on each memory access.
Address sanitizer uses 1/8 of the memory addressable in kernel for shadow
memory and uses direct mapping with a scale and offset to translate a
memory address to its corresponding shadow address.
Here is function to translate address to corresponding shadow address:
unsigned long kasan_mem_to_shadow(unsigned long addr)
{
return (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET;
}
where KASAN_SHADOW_SCALE_SHIFT = 3.
So for every 8 bytes there is one corresponding byte of shadow memory.
The following encoding used for each shadow byte: 0 means that all 8 bytes
of the corresponding memory region are valid for access; k (1 <= k <= 7)
means that the first k bytes are valid for access, and other (8 - k) bytes
are not; Any negative value indicates that the entire 8-bytes are
inaccessible. Different negative values used to distinguish between
different kinds of inaccessible memory (redzones, freed memory) (see
mm/kasan/kasan.h).
To be able to detect accesses to bad memory we need a special compiler.
Such compiler inserts a specific function calls (__asan_load*(addr),
__asan_store*(addr)) before each memory access of size 1, 2, 4, 8 or 16.
These functions check whether memory region is valid to access or not by
checking corresponding shadow memory. If access is not valid an error
printed.
Historical background of the address sanitizer from Dmitry Vyukov:
"We've developed the set of tools, AddressSanitizer (Asan),
ThreadSanitizer and MemorySanitizer, for user space. We actively use
them for testing inside of Google (continuous testing, fuzzing,
running prod services). To date the tools have found more than 10'000
scary bugs in Chromium, Google internal codebase and various
open-source projects (Firefox, OpenSSL, gcc, clang, ffmpeg, MySQL and
lots of others): [2] [3] [4].
The tools are part of both gcc and clang compilers.
We have not yet done massive testing under the Kernel AddressSanitizer
(it's kind of chicken and egg problem, you need it to be upstream to
start applying it extensively). To date it has found about 50 bugs.
Bugs that we've found in upstream kernel are listed in [5].
We've also found ~20 bugs in out internal version of the kernel. Also
people from Samsung and Oracle have found some.
[...]
As others noted, the main feature of AddressSanitizer is its
performance due to inline compiler instrumentation and simple linear
shadow memory. User-space Asan has ~2x slowdown on computational
programs and ~2x memory consumption increase. Taking into account that
kernel usually consumes only small fraction of CPU and memory when
running real user-space programs, I would expect that kernel Asan will
have ~10-30% slowdown and similar memory consumption increase (when we
finish all tuning).
I agree that Asan can well replace kmemcheck. We have plans to start
working on Kernel MemorySanitizer that finds uses of unitialized
memory. Asan+Msan will provide feature-parity with kmemcheck. As
others noted, Asan will unlikely replace debug slab and pagealloc that
can be enabled at runtime. Asan uses compiler instrumentation, so even
if it is disabled, it still incurs visible overheads.
Asan technology is easily portable to other architectures. Compiler
instrumentation is fully portable. Runtime has some arch-dependent
parts like shadow mapping and atomic operation interception. They are
relatively easy to port."
Comparison with other debugging features:
========================================
KMEMCHECK:
- KASan can do almost everything that kmemcheck can. KASan uses
compile-time instrumentation, which makes it significantly faster than
kmemcheck. The only advantage of kmemcheck over KASan is detection of
uninitialized memory reads.
Some brief performance testing showed that kasan could be
x500-x600 times faster than kmemcheck:
$ netperf -l 30
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to localhost (127.0.0.1) port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec
no debug: 87380 16384 16384 30.00 41624.72
kasan inline: 87380 16384 16384 30.00 12870.54
kasan outline: 87380 16384 16384 30.00 10586.39
kmemcheck: 87380 16384 16384 30.03 20.23
- Also kmemcheck couldn't work on several CPUs. It always sets
number of CPUs to 1. KASan doesn't have such limitation.
DEBUG_PAGEALLOC:
- KASan is slower than DEBUG_PAGEALLOC, but KASan works on sub-page
granularity level, so it able to find more bugs.
SLUB_DEBUG (poisoning, redzones):
- SLUB_DEBUG has lower overhead than KASan.
- SLUB_DEBUG in most cases are not able to detect bad reads,
KASan able to detect both reads and writes.
- In some cases (e.g. redzone overwritten) SLUB_DEBUG detect
bugs only on allocation/freeing of object. KASan catch
bugs right before it will happen, so we always know exact
place of first bad read/write.
[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel
[2] https://code.google.com/p/address-sanitizer/wiki/FoundBugs
[3] https://code.google.com/p/thread-sanitizer/wiki/FoundBugs
[4] https://code.google.com/p/memory-sanitizer/wiki/FoundBugs
[5] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel#Trophies
Based on work by Andrey Konovalov.
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull LED subsystem update from Bryan Wu:
"The big change of LED subsystem is introducing a new LED class for
Flash type LEDs which will be used for V4L2 subsystem.
Also we got some cleanup and fixes"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
leds: leds-gpio: Pass on error codes unmodified
DT: leds: Add led-sources property
leds: Add LED Flash class extension to the LED subsystem
leds: leds-mc13783: Use of_get_child_by_name() instead of refcount hack
leds: Use setup_timer
leds: Don't allow brightness values greater than max_brightness
DT: leds: Add flash LED devices related properties
Pull KVM update from Paolo Bonzini:
"Fairly small update, but there are some interesting new features.
Common:
Optional support for adding a small amount of polling on each HLT
instruction executed in the guest (or equivalent for other
architectures). This can improve latency up to 50% on some
scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests). This
also has to be enabled manually for now, but the plan is to
auto-tune this in the future.
ARM/ARM64:
The highlights are support for GICv3 emulation and dirty page
tracking
s390:
Several optimizations and bugfixes. Also a first: a feature
exposed by KVM (UUID and long guest name in /proc/sysinfo) before
it is available in IBM's hypervisor! :)
MIPS:
Bugfixes.
x86:
Support for PML (page modification logging, a new feature in
Broadwell Xeons that speeds up dirty page tracking), nested
virtualization improvements (nested APICv---a nice optimization),
usual round of emulation fixes.
There is also a new option to reduce latency of the TSC deadline
timer in the guest; this needs to be tuned manually.
Some commits are common between this pull and Catalin's; I see you
have already included his tree.
Powerpc:
Nothing yet.
The KVM/PPC changes will come in through the PPC maintainers,
because I haven't received them yet and I might end up being
offline for some part of next week"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits)
KVM: ia64: drop kvm.h from installed user headers
KVM: x86: fix build with !CONFIG_SMP
KVM: x86: emulate: correct page fault error code for NoWrite instructions
KVM: Disable compat ioctl for s390
KVM: s390: add cpu model support
KVM: s390: use facilities and cpu_id per KVM
KVM: s390/CPACF: Choose crypto control block format
s390/kernel: Update /proc/sysinfo file with Extended Name and UUID
KVM: s390: reenable LPP facility
KVM: s390: floating irqs: fix user triggerable endless loop
kvm: add halt_poll_ns module parameter
kvm: remove KVM_MMIO_SIZE
KVM: MIPS: Don't leak FPU/DSP to guest
KVM: MIPS: Disable HTW while in guest
KVM: nVMX: Enable nested posted interrupt processing
KVM: nVMX: Enable nested virtual interrupt delivery
KVM: nVMX: Enable nested apic register virtualization
KVM: nVMX: Make nested control MSRs per-cpu
KVM: nVMX: Enable nested virtualize x2apic mode
KVM: nVMX: Prepare for using hardware MSR bitmap
...
Pull f2fs updates from Jaegeuk Kim:
"Major changes are to:
- add f2fs_io_tracer and F2FS_IOC_GETVERSION
- fix wrong acl assignment from parent
- fix accessing wrong data blocks
- fix wrong condition check for f2fs_sync_fs
- align start block address for direct_io
- add and refactor the readahead flows of FS metadata
- refactor atomic and volatile write policies
But most of patches are for clean-ups and minor bug fixes. Some of
them refactor old code too"
* tag 'for-f2fs-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (64 commits)
f2fs: use spinlock for segmap_lock instead of rwlock
f2fs: fix accessing wrong indexed data blocks
f2fs: avoid variable length array
f2fs: fix sparse warnings
f2fs: allocate data blocks in advance for f2fs_direct_IO
f2fs: introduce macros to convert bytes and blocks in f2fs
f2fs: call set_buffer_new for get_block
f2fs: check node page contents all the time
f2fs: avoid data offset overflow when lseeking huge file
f2fs: fix to use highmem for pages of newly created directory
f2fs: introduce a batched trim
f2fs: merge {invalidate,release}page for meta/node/data pages
f2fs: show the number of writeback pages in stat
f2fs: keep PagePrivate during releasepage
f2fs: should fail mount when trying to recover data on read-only dev
f2fs: split UMOUNT and FASTBOOT flags
f2fs: avoid write_checkpoint if f2fs is mounted readonly
f2fs: support norecovery mount option
f2fs: fix not to drop mount options when retrying fill_super
f2fs: merge flags in struct f2fs_sb_info
...
Linus Torvalds
Jonathan Corbet
Mikulas Patocka
Dmitry Torokhov
Pali Rohár
Gregory CLEMENT
Arnaud Ebalard
Joshua Clayton
Andrey Ryabinin
Andrew Morton
Luis R. Rodriguez