During init the core checks if the wm5102 has finished starting by reading
register 0x19 and looking at the value. This read always fails since this
is not a readable register, mark it as being one. While we're at it provide
a constant for the register name (as supplied by Charles Keepax).
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Calling strncpy with a maximum size argument of 32 bytes on destination
array kim_gdata->dev_name of size 32 bytes might leave the destination
string unterminated.
Cc: gregkh@linuxfoundation.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Various drivers implement architecture and/or device specific means to
restart (reset) the system. Various mechanisms have been implemented to
support those schemes. The best known mechanism is arm_pm_restart, which
is a function pointer to be set either from platform specific code or from
drivers. Another mechanism is to use hardware watchdogs to issue a reset;
this mechanism is used if there is no other method available to reset a
board or system. Two examples are alim7101_wdt, which currently uses the
reboot notifier to trigger a reset, and moxart_wdt, which registers the
arm_pm_restart function.
The existing mechanisms have a number of drawbacks. Typically only one
scheme to restart the system is supported (at least if arm_pm_restart is
used). At least in theory there can be multiple means to restart the
system, some of which may be less desirable (for example one mechanism may
only reset the CPU, while another may reset the entire system). Using
arm_pm_restart can also be racy if the function pointer is set from a
driver, as the driver may be in the process of being unloaded when
arm_pm_restart is called. Using the reboot notifier is always racy, as it
is unknown if and when other functions using the reboot notifier have
completed execution by the time the watchdog fires.
Introduce a system restart handler call chain to solve the described
problems. This call chain is expected to be executed from the
architecture specific machine_restart() function. Drivers providing
system restart functionality (such as the watchdog drivers mentioned
above) are expected to register with this call chain. By using the
priority field in the notifier block, callers can control restart handler
execution sequence and thus ensure that the restart handler with the
optimal restart capabilities for a given system is called first.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The send_check logic was only interesting in cases of TCP offload and
UDP UFO where the checksum needed to be initialized to the pseudo
header checksum. Now we've moved that logic into the related
gso_segment functions so gso_send_check is no longer needed.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If CONFIG_COMMON_CLK is selected then __clk_get and __clk_put are
defined in drivers/clk/clk.c and declared in include/linux/clkdev.h.
Sylwester's series[0] to properly support clk_{get,put} in the common
clock framework made changes to the asm-specific clkdev.h headers, but
not the asm-generic version. Tomeu's recent changes[1] to introduce a
provider/consumer split in the clock framework uncovered this problem,
causing the following build error on any architecture using the
asm-generic clkdev.h (e.g. x86 architecture and the ACPI LPSS driver):
In file included from drivers/acpi/acpi_lpss.c:15:0:
include/linux/clkdev.h:59:5: error: conflicting types for ‘__clk_get’
int __clk_get(struct clk_core *clk);
^
In file included from arch/x86/include/generated/asm/clkdev.h:1:0,
from include/linux/clkdev.h:15,
from drivers/acpi/acpi_lpss.c:15:
include/asm-generic/clkdev.h:20:19: note: previous definition of ‘__clk_get’ was here
static inline int __clk_get(struct clk *clk) { return 1; }
^
Fixed by only declarating __clk_get and __clk_put when
CONFIG_COMMON_CLK is set.
[0] http://lkml.kernel.org/r/<1386177127-2894-5-git-send-email-s.nawrocki@samsung.com>
[1] http://lkml.kernel.org/r/<1409758148-20104-1-git-send-email-tomeu.vizoso@collabora.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
- Revert of a recent hibernation core commit that introduced
a NULL pointer dereference during resume for at least one user
(Rafael J Wysocki).
- Fix for the ACPI LPSS (Low-Power Subsystem) driver to disable
asynchronous PM callback execution for LPSS devices during system
suspend/resume (introduced in 3.16) which turns out to break
ordering expectations on some systems. From Fu Zhonghui.
- cpufreq core fix related to the handling of sysfs nodes during
system suspend/resume that has been broken for intel_pstate
since 3.15 from Lan Tianyu.
- Restore the generation of "online" uevents for ACPI container
devices that was removed in 3.14, but some user space utilities
turn out to need them (Rafael J Wysocki).
- The cpufreq core fails to release a lock in an error code path
after changes made in 3.14. Fix from Prarit Bhargava.
- ACPICA and ACPI/GPIO fixes to make the handling of ACPI GPIO
operation regions (which means AML using GPIOs) work correctly
in all cases from Bob Moore and Srinivas Pandruvada.
- Fix for a wrong sign of the ACPI core's create_modalias() return
value in case of an error from Mika Westerberg.
- ACPI backlight blacklist entry for ThinkPad X201s from Aaron Lu.
/
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Merge tag 'pm+acpi-3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management fixes from Rafael Wysocki:
"These are regression fixes (ACPI hotplug, cpufreq, hibernation, ACPI
LPSS driver), fixes for stuff that never worked correctly (ACPI GPIO
support in some cases and a wrong sign of an error code in the ACPI
core in one place), and one blacklist item for ACPI backlight
handling.
Specifics:
- Revert of a recent hibernation core commit that introduced a NULL
pointer dereference during resume for at least one user (Rafael J
Wysocki).
- Fix for the ACPI LPSS (Low-Power Subsystem) driver to disable
asynchronous PM callback execution for LPSS devices during system
suspend/resume (introduced in 3.16) which turns out to break
ordering expectations on some systems. From Fu Zhonghui.
- cpufreq core fix related to the handling of sysfs nodes during
system suspend/resume that has been broken for intel_pstate since
3.15 from Lan Tianyu.
- Restore the generation of "online" uevents for ACPI container
devices that was removed in 3.14, but some user space utilities
turn out to need them (Rafael J Wysocki).
- The cpufreq core fails to release a lock in an error code path
after changes made in 3.14. Fix from Prarit Bhargava.
- ACPICA and ACPI/GPIO fixes to make the handling of ACPI GPIO
operation regions (which means AML using GPIOs) work correctly in
all cases from Bob Moore and Srinivas Pandruvada.
- Fix for a wrong sign of the ACPI core's create_modalias() return
value in case of an error from Mika Westerberg.
- ACPI backlight blacklist entry for ThinkPad X201s from Aaron Lu"
* tag 'pm+acpi-3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "PM / Hibernate: Iterate over set bits instead of PFNs in swsusp_free()"
gpio / ACPI: Use pin index and bit length
ACPICA: Update to GPIO region handler interface.
ACPI / platform / LPSS: disable async suspend/resume of LPSS devices
cpufreq: release policy->rwsem on error
cpufreq: fix cpufreq suspend/resume for intel_pstate
ACPI / scan: Correct error return value of create_modalias()
ACPI / video: disable native backlight for ThinkPad X201s
ACPI / hotplug: Generate online uevents for ACPI containers
- introduction of the new SAMA5D4 SoC and associated Evaluation Kit
- low level soc detection and early printk code
- taking advantage of this, documentation of all AT91 SoC DT strings
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Merge tag 'at91-soc2' of git://github.com/at91linux/linux-at91 into next/soc
Pull "Second SoC batch for 3.18" from Nicolas Ferre:
- introduction of the new SAMA5D4 SoC and associated Evaluation Kit
- low level soc detection and early printk code
- taking advantage of this, documentation of all AT91 SoC DT strings
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* tag 'at91-soc2' of git://github.com/at91linux/linux-at91:
ARM: at91: document Atmel SMART compatibles
ARM: at91: add sama5d4 support to sama5_defconfig
ARM: at91: dt: add device tree file for SAMA5D4ek board
ARM: at91: dt: add device tree file for SAMA5D4 SoC
ARM: at91: SAMA5D4 SoC detection code and low level routines
ARM: at91: introduce basic SAMA5D4 support
clk: at91: add a driver for the h32mx clock
- Remove unused pieces of the legacy DMA API as we're moving to
dmaengine API
- Search and replace to standardize on pr_warn instead of pr_warning
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Merge tag 'cleanup-for-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/cleanup
Pull "Clean-up for omaps for v3.18 merge window" from Tony Lindgren:
- Remove unused pieces of the legacy DMA API as we're moving to
dmaengine API
- Search and replace to standardize on pr_warn instead of pr_warning
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* tag 'cleanup-for-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
arm: mach-omap2: Convert pr_warning to pr_warn
ARM: OMAP: Remove unused pieces of legacy DMA API
Pull i2c fixes from Wolfram Sang:
"This is probably not the kind of pull request you want to see that
late in the cycle. Yet, the ACPI refactorization was problematic
again and caused another two issues which need fixing. My holidays
with limited internet (plus travelling) and the developer's illness
didn't help either :(
The details:
- ACPI code was refactored out into a seperate file and as a
side-effect, the i2c-core module got renamed. Jean Delvare
rightfully complained about the rename being problematic for
distributions. So, Mika and I thought the least problematic way to
deal with it is to move all the code back into the main i2c core
source file. This is mainly a huge code move with some #ifdeffery
applied. No functional code changes. Our personal tests and the
testbots did not find problems. (I was thinking about reverting,
too, yet that would also have ~800 lines changed)
- The new ACPI code also had a NULL pointer exception, thanks to
Peter for finding and fixing it.
- Mikko fixed a locking problem by decoupling clock_prepare and
clock_enable.
- Addy learnt that the datasheet was wrong and reimplemented the
frequency setup according to the new algorithm.
- Fan fixed an off-by-one error when copying data
- Janusz fixed a copy'n'paste bug which gave a wrong error message
- Sergei made sure that "don't touch" bits are not accessed"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: acpi: Fix NULL Pointer dereference
i2c: move acpi code back into the core
i2c: rk3x: fix divisor calculation for SCL frequency
i2c: mxs: fix error message in pio transfer
i2c: ismt: use correct length when copy buffer
i2c: rcar: fix RCAR_IRQ_ACK_{RECV|SEND}
i2c: tegra: Move clk_prepare/clk_set_rate to probe
move it to drivers.
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Merge tag 'intc-part2-for-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/drivers
Merge "part 2 of omap intc changes" from Tony Lindgren:
Second part of omap intc interrupt controller changes to
move it to drivers.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* tag 'intc-part2-for-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
irqchip: omap-intc: remove unnecessary comments
irqchip: omap-intc: correct maximum number or MIR registers
irqchip: omap-intc: enable TURBO idle mode
irqchip: omap-intc: enable IP protection
irqchip: omap-intc: remove unnecesary of_address_to_resource() call
irqchip: omap-intc: comment style cleanup
irqchip: omap-intc: minor improvement to omap_irq_pending()
arm: omap: irq: move irq.c to drivers/irqchip/
irqchip: add irq-omap-intc.h header
arm: omap2: n8x0: move i2c devices to DT
This patch add some clock binding id for different modules
that under development and going to send upstream.
Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The patch add the rest of the indices of the additional reset
registers from the updated TRM.
Signed-off-by: Mark yao <mark.yao@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
This patch supports to run one single flush machinery for
each blk-mq dispatch queue, so that:
- current init_request and exit_request callbacks can
cover flush request too, then the buggy copying way of
initializing flush request's pdu can be fixed
- flushing performance gets improved in case of multi hw-queue
In fio sync write test over virtio-blk(4 hw queues, ioengine=sync,
iodepth=64, numjobs=4, bs=4K), it is observed that througput gets
increased a lot over my test environment:
- throughput: +70% in case of virtio-blk over null_blk
- throughput: +30% in case of virtio-blk over SSD image
The multi virtqueue feature isn't merged to QEMU yet, and patches for
the feature can be found in below tree:
git://kernel.ubuntu.com/ming/qemu.git v2.1.0-mq.4
And simply passing 'num_queues=4 vectors=5' should be enough to
enable multi queue(quad queue) feature for QEMU virtio-blk.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch introduces 'struct blk_flush_queue' and puts all
flush machinery related fields into this structure, so that
- flush implementation details aren't exposed to driver
- it is easy to convert to per dispatch-queue flush machinery
This patch is basically a mechanical replacement.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
- Add new driver for Rockchip IO voltage domains
- update MAINTAINERS to reflect maintenance of drivers/power/avs/*
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Merge tag 'avs-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux into pm-avs
Pull AVS changes for v3.18 from Kevin Hilman:
- Add new driver for Rockchip IO voltage domains
- update MAINTAINERS to reflect maintenance of drivers/power/avs/*
* tag 'avs-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux:
MAINTAINERS: update entry for drivers/power/avs
PM / AVS: rockchip-io: add driver handling Rockchip io domains
There are no active clients of the legacy API and we now also have a
better way to handle genpd DT support. So let's remove the legacy API.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
While a PM domain can enable PM runtime management of its devices' module
clocks by setting
genpd->dev_ops.stop = pm_clk_suspend;
genpd->dev_ops.start = pm_clk_resume;
this also requires registering the clocks with the pm_clk subsystem.
In the legacy case, this is handled by the platform code, after
attaching the device to its PM domain.
When the devices are instantiated from DT, devices are attached to their
PM domains by generic code, leaving no method for the platform-specific
PM domain code to register their clocks.
Add two callbacks, allowing a PM domain to perform platform-specific
tasks when a device is attached to or detached from a PM domain.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
the primary change here gets its address information from DT rather than
iomap.h. This removes one more user of iomap.h, and will help allow the
code to move to a location that can be shared between arch/arm and
arch/arm64.
An unused header file was also removed.
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Merge tag 'tegra-for-3.18-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/soc
Pull "ARM: tegra: core SoC code changes for 3.18" from Stephen Warren:
the primary change here gets its address information from DT rather than
iomap.h. This removes one more user of iomap.h, and will help allow the
code to move to a location that can be shared between arch/arm and
arch/arm64.
An unused header file was also removed.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* tag 'tegra-for-3.18-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra:
ARM: tegra: remove unused tegra_emc.h
ARM: tegra: Initialize flow controller from DT
of: Add NVIDIA Tegra flow controller bindings
In PCIe r1.0, sec 5.10.2, bit 0 of the Uncorrectable Error Status, Mask,
and Severity Registers was for "Training Error." In PCIe r1.1, sec 7.10.2,
bit 0 was redefined to be "Undefined."
Rename PCI_ERR_UNC_TRAIN to PCI_ERR_UNC_UND to reflect this change.
No functional change.
[bhelgaas: changelog]
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add all AER error bits defined in PCIe r3.0.
[bhelgaas: changelog]
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Replace bare numbers like "BIT(0)" with the existing #defines, e.g.,
PCI_ERR_COR_RCVR, to improve maintainability. This way grep will find more
uses of the #defines.
No functional change.
[bhelgaas: changelog]
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
With this patch, USB activity can be signaled by blinking a LED. There
are two triggers, one for activity on USB host and one for USB gadget.
Both triggers should work with all host/device controllers. Tested only
with musb.
Performace: I measured performance overheads on ARM Cortex-A8 (TI
AM335x) running on 600 MHz.
Duration of usb_led_activity():
- with no LED attached to the trigger: 2 ± 1 µs
- with one GPIO LED attached to the trigger: 2 ± 1 µs or 8 ± 2 µs (two peaks in histogram)
Duration of functions calling usb_led_activity() (with this patch
applied and no LED attached to the trigger):
- __usb_hcd_giveback_urb(): 10 - 25 µs
- usb_gadget_giveback_request(): 2 - 6 µs
Signed-off-by: Michal Sojka <sojka@merica.cz>
Acked-by: Felipe Balbi <balbi@ti.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
All USB peripheral controller drivers call completion routines directly.
This patch adds usb_gadget_giveback_request() which will be used instead
of direct invocation in the next patch. The goal here is to have a place
where common functionality can be added.
Signed-off-by: Michal Sojka <sojka@merica.cz>
Acked-by: Felipe Balbi <balbi@ti.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 5d98e61d33 ("I2C/ACPI: Add i2c ACPI operation region support")
renamed the i2c-core module. This may cause regressions for
distributions, so put the ACPI code back into the core.
Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Lan Tianyu <tianyu.lan@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This function will replace the current iommu_domain_has_cap
function and clean up the interface while at it.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
These new-lines add empty lines to trace output
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This will allow NFS to wait for PG_private to be cleared and,
particularly, to send a wake-up when it is.
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In commit c1221321b7
sched: Allow wait_on_bit_action() functions to support a timeout
I suggested that a "wait_on_bit_timeout()" interface would not meet my
need. This isn't true - I was just over-engineering.
Including a 'private' field in wait_bit_key instead of a focused
"timeout" field was just premature generalization. If some other
use is ever found, it can be generalized or added later.
So this patch renames "private" to "timeout" with a meaning "stop
waiting when "jiffies" reaches or passes "timeout",
and adds two of the many possible wait..bit..timeout() interfaces:
wait_on_page_bit_killable_timeout(), which is the one I want to use,
and out_of_line_wait_on_bit_timeout() which is a reasonably general
example. Others can be added as needed.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
includes miscellaneous cleanup of other PHY drivers.
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Merge tag 'phy-for_3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kishon/linux-phy into usb-next
Kishon writes:
Adds 3 new PHY drivers stih407, stih41x and rcar gen2 PHY. It also
includes miscellaneous cleanup of other PHY drivers.
Conflicts:
MAINTAINERS
Commit c545b66c69,
'tty: Serialize tcflow() with other tty flow control changes' and
commit 99416322dd,
'tty: Workaround Alpha non-atomic byte storage in tty_struct' work around
compiler bugs and non-atomic storage on multiple arches by padding
bitfields out to the declared type which is unsigned long. However, the
width varies by arch.
Pad bitfields to actual width of unsigned long (which is BITS_PER_LONG).
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently asynchronous NFSv4 request will be retried with
exponential timeout (from 1/10 to 15 seconds), but async
requests will always use a 15second retry.
Some "async" requests are really synchronous though. The
async mechanism is used to allow the request to continue if
the requesting process is killed.
In those cases, an exponential retry is appropriate.
For example, if two different clients both open a file and
get a READ delegation, and one client then unlinks the file
(while still holding an open file descriptor), that unlink
will used the "silly-rename" handling which is async.
The first rename will result in NFS4ERR_DELAY while the
delegation is reclaimed from the other client. The rename
will not be retried for 15 seconds, causing an unlink to take
15 seconds rather than 100msec.
This patch only added exponential timeout for async unlink and
async rename. Other async calls, such as 'close' are sometimes
waited for so they might benefit from exponential timeout too.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When aborting a connection to preserve source ports, don't wake the task in
xs_error_report. This allows tasks with RPC_TASK_SOFTCONN to succeed if the
connection needs to be re-established since it preserves the task's status
instead of setting it to the status of the aborting kernel_connect().
This may also avoid a potential conflict on the socket's lock.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When we change cpuset.memory_spread_{page,slab}, cpuset will flip
PF_SPREAD_{PAGE,SLAB} bit of tsk->flags for each task in that cpuset.
This should be done using atomic bitops, but currently we don't,
which is broken.
Tetsuo reported a hard-to-reproduce kernel crash on RHEL6, which happened
when one thread tried to clear PF_USED_MATH while at the same time another
thread tried to flip PF_SPREAD_PAGE/PF_SPREAD_SLAB. They both operate on
the same task.
Here's the full report:
https://lkml.org/lkml/2014/9/19/230
To fix this, we make PF_SPREAD_PAGE and PF_SPREAD_SLAB atomic flags.
v4:
- updated mm/slab.c. (Fengguang Wu)
- updated Documentation.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Fixes: 950592f7b9 ("cpusets: update tasks' page/slab spread flags in time")
Cc: <stable@vger.kernel.org> # 2.6.31+
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This will simplify code when we add new flags.
v3:
- Kees pointed out that no_new_privs should never be cleared, so we
shouldn't define task_clear_no_new_privs(). we define 3 macros instead
of a single one.
v2:
- updated scripts/tags.sh, suggested by Peter
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Commit 1d4457f999 ("sched: move no_new_privs into new atomic flags")
defined PFA_NO_NEW_PRIVS as hexadecimal value, but it is confusing
because it is used as bit number. Redefine it as decimal bit number.
Note this changes the bit position of PFA_NOW_NEW_PRIVS from 1 to 0.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Kees Cook <keescook@chromium.org>
[ lizf: slightly modified subject and changelog ]
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Also adds a class type PM_QOS_SUM that aggregates the values by summing them.
It can be used by memory controllers to calculate the optimum clock frequency
based on the bandwidth needs of the different memory clients.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* pci/hotplug:
PCI: pciehp: Stop disabling notifications during init
PCI: pciehp: Add more Slot Control debug output
PCI: pciehp: Fix wait time in timeout message
* pci/initdata:
x86/PCI: Mark PCI BIOS initialization code as such
x86/PCI: Constify pci_mmcfg_probes[] array
x86/PCI: Mark constants of pci_mmcfg_nvidia_mcp55() as __initconst
x86/PCI: Move __init annotation to the correct place
x86/PCI: Mark DMI tables as initialization data
* pci/misc:
PCI: Move PCI_VENDOR_ID_VMWARE to pci_ids.h
Fixes below build break by not switching to stubs when the driver is a module:
drivers/soc/ti/knav_dma.c:418:7: error: redefinition of 'knav_dma_open_channel'
void *knav_dma_open_channel(struct device *dev, const char *name,
^
In file included from drivers/soc/ti/knav_dma.c:26:0:
include/linux/soc/ti/knav_dma.h:165:21: note: previous definition of 'knav_dma_open_channel' was here
static inline void *knav_dma_open_channel(struct device *dev, const char *name,
^
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
- Device tree support for i.MX ADS and Armadeus APF9328 boards
- Enable thermal sensor support for i.MX6SL
- Add LCD support for i.MX6SL EVK board
- Fix display duplicate name for a bunch of board dts files
- Configure imx6qdl-sabresd board pins locally to remove the dependency
on bootloader
- A set of imx28-tx28 board dts updates from Lothar
- Add pci config space as platform resource
- Enable devices RTC, I2C and HDMI for nitrogen6x board
- Split HummingBoard DT to support s/dl and d/q
- mSATA and IR input support for HummingBoard
- Add SSI baud clock for i.MX6 device trees
- Add USB support for vf610-colibri and vf610-twr boards
- A set of cleanup and updates on Gateworks boards
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Merge tag 'imx-dt-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into next/dt
Merge "ARM: imx: device tree changes for 3.18" from Shawn Guo:
The i.MX device tree changes for 3.18:
- Device tree support for i.MX ADS and Armadeus APF9328 boards
- Enable thermal sensor support for i.MX6SL
- Add LCD support for i.MX6SL EVK board
- Fix display duplicate name for a bunch of board dts files
- Configure imx6qdl-sabresd board pins locally to remove the dependency
on bootloader
- A set of imx28-tx28 board dts updates from Lothar
- Add pci config space as platform resource
- Enable devices RTC, I2C and HDMI for nitrogen6x board
- Split HummingBoard DT to support s/dl and d/q
- mSATA and IR input support for HummingBoard
- Add SSI baud clock for i.MX6 device trees
- Add USB support for vf610-colibri and vf610-twr boards
- A set of cleanup and updates on Gateworks boards
* tag 'imx-dt-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux: (86 commits)
ARM: dts: imx6: make gpt per clock can be from OSC
ARM: dts: imx: ventana: add canbus support for GW52xx
ARM: dts: imx: ventana: cleanup pinctrl groups
ARM: dts: imx: ventana: configure padconf for all pins
ARM: dts: imx: ventana: use gpio constants
ARM: dts: imx: ventana: remove unused aliases
ARM: dts: imx: ventana: remove unsupported dt nodes
ARM: dts: imx28-tx28: add alias for CAN XCVR regulator
ARM: dts: imx28-tx28: add spi-gpio as alternative for spi-mxs
ARM: dts: imx28-tx28: use GPIO flags
ARM: dts: imx28-tx28: remove spidev labels and add third instance of spidev
ARM: dts: imx6sl: add baud clock and clock-names for ssi
ARM: dts: imx6qdl: add baud clock and clock-names for ssi
ARM: dts: imx6qdl-sabresd: Configure the pins locally
ARM: dts: imx28-m28evk: Fix display duplicate name warning
ARM: dts: imx28-tx28: Fix display duplicate name warning
ARM: dts: imx28-m28cu: Fix display duplicate name warning
ARM: dts: imx28-cfa100: Fix display duplicate name warning
ARM: dts: imx28-apf28dev: Fix display duplicate name warning
ARM: dts: imx28-apx4devkit: Fix display duplicate name warning
...
Signed-off-by: Olof Johansson <olof@lixom.net>
- Add initial devicetree support for i.MX1
- Support GPT per clock source from OSC for i.MX6
- A couple of parent selection corrections for i.MX6SL clock driver
- Support more chip revision for i.MX6
- Convert pr_warning to pr_warn
- Add exclusive gate clock support
- Add BYPASS support for i.MX6 PLL clocks
- Update i.MX6 clock tree for audio use case
- A couple of VF610 clock driver updates
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Merge tag 'imx-soc-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into next/soc
Merge "ARM: imx: SoC updates for 3.18" from Shawn Guo:
The i.MX SoC updates for 3.18:
- Add initial devicetree support for i.MX1
- Support GPT per clock source from OSC for i.MX6
- A couple of parent selection corrections for i.MX6SL clock driver
- Support more chip revision for i.MX6
- Convert pr_warning to pr_warn
- Add exclusive gate clock support
- Add BYPASS support for i.MX6 PLL clocks
- Update i.MX6 clock tree for audio use case
- A couple of VF610 clock driver updates
* tag 'imx-soc-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux: (30 commits)
ARM: imx_v6_v7_defconfig updates
ARM: imx_v4_v5_defconfig: Select CONFIG_IMX_WEIM
arm: mach-imx: Convert pr_warning to pr_warn
ARM: imx: source gpt per clk from OSC for system timer
ARM: imx: add gpt_3m clk for i.mx6qdl
ARM: imx: fix register offset of pll7_usb_host gate clock
ARM: clk-imx6sl: refine clock tree for SSI
ARM: imx: remove ENABLE and BYPASS bits from clk-pllv3 driver
ARM: imx6sx: add BYPASS support for PLL clocks
ARM: imx6sl: add BYPASS support for PLL clocks
ARM: imx6q: add BYPASS support for PLL clocks
ARM: imx: add an exclusive gate clock type
ARM: clk-imx6q: refine clock tree for SSI
ARM: clk-imx6q: refine clock tree for ASRC
ARM: clk-imx6sl: correct the pxp and epdc axi clock selections
ARM: clk-imx6q: refine clock tree for ESAI
ARM: clk-imx6sl: Select appropriate parents for LCDIF clocks
ARM: clk-imx6sl: Remove csi_lcdif_sels[]
ARM: imx: clk-vf610: Add USBPHY clocks
ARM: imx: add cpufreq support for i.mx6sx
...
Signed-off-by: Olof Johansson <olof@lixom.net>
Move PCI_VENDOR_ID_VMWARE from device-specific files to pci_ids.h.
It is useful to always have access to it, especially when accessing
subsystem_vendor_id on emulated devices.
[bhelgaas: keep pci_ids.h sorted and use lower-case hex]
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
blk-mq uses percpu_ref for its usage counter which tracks the number
of in-flight commands and used to synchronously drain the queue on
freeze. percpu_ref shutdown takes measureable wallclock time as it
involves a sched RCU grace period. This means that draining a blk-mq
takes measureable wallclock time. One would think that this shouldn't
matter as queue shutdown should be a rare event which takes place
asynchronously w.r.t. userland.
Unfortunately, SCSI probing involves synchronously setting up and then
tearing down a lot of request_queues back-to-back for non-existent
LUNs. This means that SCSI probing may take above ten seconds when
scsi-mq is used.
[ 0.949892] scsi host0: Virtio SCSI HBA
[ 1.007864] scsi 0:0:0:0: Direct-Access QEMU QEMU HARDDISK 1.1. PQ: 0 ANSI: 5
[ 1.021299] scsi 0:0:1:0: Direct-Access QEMU QEMU HARDDISK 1.1. PQ: 0 ANSI: 5
[ 1.520356] tsc: Refined TSC clocksource calibration: 2491.910 MHz
<stall>
[ 16.186549] sd 0:0:0:0: Attached scsi generic sg0 type 0
[ 16.190478] sd 0:0:1:0: Attached scsi generic sg1 type 0
[ 16.194099] osd: LOADED open-osd 0.2.1
[ 16.203202] sd 0:0:0:0: [sda] 31457280 512-byte logical blocks: (16.1 GB/15.0 GiB)
[ 16.208478] sd 0:0:0:0: [sda] Write Protect is off
[ 16.211439] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 16.218771] sd 0:0:1:0: [sdb] 31457280 512-byte logical blocks: (16.1 GB/15.0 GiB)
[ 16.223264] sd 0:0:1:0: [sdb] Write Protect is off
[ 16.225682] sd 0:0:1:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
This is also the reason why request_queues start in bypass mode which
is ended on blk_register_queue() as shutting down a fully functional
queue also involves a RCU grace period and the queues for non-existent
SCSI devices never reach registration.
blk-mq basically needs to do the same thing - start the mq in a
degraded mode which is faster to shut down and then make it fully
functional only after the queue reaches registration. percpu_ref
recently grew facilities to force atomic operation until explicitly
switched to percpu mode, which can be used for this purpose. This
patch makes blk-mq initialize q->mq_usage_counter in atomic mode and
switch it to percpu mode only once blk_register_queue() is reached.
Note that this issue was previously worked around by 0a30288da1
("blk-mq, percpu_ref: implement a kludge for SCSI blk-mq stall during
probe") for v3.17. The temp fix was reverted in preparation of adding
persistent atomic mode to percpu_ref by 9eca80461a ("Revert "blk-mq,
percpu_ref: implement a kludge for SCSI blk-mq stall during probe"").
This patch and the prerequisite percpu_ref changes will be merged
during v3.18 devel cycle.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Christoph Hellwig <hch@infradead.org>
Link: http://lkml.kernel.org/g/20140919113815.GA10791@lst.de
Fixes: add703fda9 ("blk-mq: use percpu_ref for mq usage count")
Reviewed-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
