With the advent of __this_cpu_ptr(), it is no longer necessary to pass
both the rcu_state and rcu_data structures into __rcu_process_callbacks().
This commit therefore computes the rcu_data pointer from the rcu_state
pointer within __rcu_process_callbacks() so that callers can pass in
only the pointer to the rcu_state structure. This paves the way for
linking the rcu_state structures together and iterating over them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit adds an rcubarrier file to RCU's debugfs statistical tracing
directory, providing diagnostic information on rcu_barrier().
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit adds event tracing for _rcu_barrier() execution. This
is defined only if RCU_TRACE=y.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The traditional rcu_barrier() implementation has serialized all requests,
regardless of RCU flavor, and also does not coalesce concurrent requests.
In the past, this has been good and sufficient.
However, systems are getting larger and use of rcu_barrier() has been
increasing. This commit therefore introduces a counter-based scheme
that allows _rcu_barrier() calls for the same flavor of RCU to take
advantage of each others' work.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
For global variables, C defaults all fields to zero. The initialization
of the rcu_state structure's ->n_force_qs and ->n_force_qs_ngp fields
is therefore redundant, so this commit removes these initializations.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
In order to allow each RCU flavor to concurrently execute its
rcu_barrier() function, it is necessary to move the relevant
state to the rcu_state structure. This commit therefore moves the
rcu_barrier_mutex global variable to a new ->barrier_mutex field
in the rcu_state structure.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
In order to allow each RCU flavor to concurrently execute its
rcu_barrier() function, it is necessary to move the relevant
state to the rcu_state structure. This commit therefore moves the
rcu_barrier_completion global variable to a new ->barrier_completion
field in the rcu_state structure.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In order to allow each RCU flavor to concurrently execute its rcu_barrier()
function, it is necessary to move the relevant state to the rcu_state
structure. This commit therefore moves the rcu_barrier_cpu_count global
variable to a new ->barrier_cpu_count field in the rcu_state structure.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In order for multiple flavors of RCU to each concurrently run one
rcu_barrier(), each flavor needs its own per-CPU set of rcu_head
structures. This commit therefore moves _rcu_barrier()'s set of
per-CPU rcu_head structures from per-CPU variables to the existing
per-CPU and per-RCU-flavor rcu_data structures.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This is a preparatory commit for increasing rcu_barrier()'s concurrency.
It adds a pointer in the rcu_data structure to the corresponding call_rcu()
function. This allows a pointer to the rcu_data structure to imply the
function pointer, which allows _rcu_barrier() state to be placed in the
rcu_state structure.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Upcoming rcu_barrier() concurrency commits will result in line lengths
greater than 80 characters in the RCU_STATE_INITIALIZER(), so this commit
shortens the name of the macro's argument to prevent this.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The rcu_node tree array is sized based on compile-time constants,
including NR_CPUS. Although this approach has worked well in the past,
the recent trend by many distros to define NR_CPUS=4096 results in
excessive grace-period-initialization latencies.
This commit therefore substitutes the run-time computed nr_cpu_ids for
the compile-time NR_CPUS when building the tree. This can result in
much of the compile-time-allocated rcu_node array being unused. If
this is a major problem, you are in a specialized situation anyway,
so you can manually adjust the NR_CPUS, RCU_FANOUT, and RCU_FANOUT_LEAF
kernel config parameters.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Time to make the four-level-hierarchy setting less scary, so this
commit removes "Experimental" from the boot-time message. Leave the
message in order to get a heads-up on any possible need to expand to
a five-level hierarchy.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Although making RCU_FANOUT_LEAF a kernel configuration parameter rather
than a fixed constant makes it easier for people to decrease cache-miss
overhead for large systems, it is of little help for people who must
run a single pre-built kernel binary.
This commit therefore allows the value of RCU_FANOUT_LEAF to be
increased (but not decreased!) via a boot-time parameter named
rcutree.rcu_fanout_leaf.
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This reverts commit 616c310e83.
(Move PREEMPT_RCU preemption to switch_to() invocation).
Testing by Sasha Levin <levinsasha928@gmail.com> showed that this
can result in deadlock due to invoking the scheduler when one of
the runqueue locks is held. Because this commit was simply a
performance optimization, revert it.
Reported-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
Another week, another batch of fixes.
All are small, contained, targeted fixes for explicit problems -- mostly
build and boot failures across i.MX, OMAP, Renesas/Shmobile and Samsung.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Olof Johansson:
"Another week, another batch of fixes.
All are small, contained, targeted fixes for explicit problems --
mostly build and boot failures across i.MX, OMAP, Renesas/Shmobile and
Samsung."
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: imx6q: fix suspend regression caused by common clk migration
ARM: OMAP4470: Fix OMAP4470 boot failure
ARM: EXYNOS: Fix EXYNOS_DEV_DMA Kconfig entry
ARM: OMAP2+: nand: fix build error when CONFIG_MTD_ONENAND_OMAP2=n
ARM: shmobile: r8a7779: Route all interrupts to ARM
ARM: shmobile: kzm9d: use late init machine hook
ARM: shmobile: kzm9g: use late init machine hook
ARM: mach-shmobile: armadillo800eva: Use late init machine hook
ARM: SAMSUNG: Fix for S3C2412 EBI memory mapping
ARM: mach-shmobile: add missing GPIO IRQ configuration on mackerel
ARM: mach-shmobile: Fix build when SMP is enabled and EMEV2 is not enabled
ARM: shmobile: sh7372: bugfix: chclr_offset base
ARM: shmobile: sh73a0: bugfix: SY-DMAC number
ARM: SAMSUNG: Should check for IS_ERR(clk) instead of NULL
Fix kernel-doc warnings in printk.c: use correct parameter name.
Warning(kernel/printk.c:2429): No description found for parameter 'buf'
Warning(kernel/printk.c:2429): Excess function parameter 'line' description in 'kmsg_dump_get_buffer'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix kernel-doc warning. This struct member was removed in commit
875682648b ("irq: Remove irq_chip->release()") so remove its
associated kernel-doc entry also.
Warning(include/linux/irq.h:338): Excess struct/union/enum/typedef member 'release' description in 'irq_chip'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When moving to common clk framework, the imx6q clks rom and mmdc_ch1_axi
get different on/off states than old clk driver, which breaks suspend
function. There might be a better way to manage these clocks, but let's
takes the old clk driver approach to fix the regression first.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
trivial fix to get omap4470 booting.
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Merge tag 'omap-fixes-for-v3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes
From Tony Lindgren:
"Here's one more regression fix that I missed earlier, and a
trivial fix to get omap4470 booting."
* tag 'omap-fixes-for-v3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP4470: Fix OMAP4470 boot failure
ARM: OMAP2+: nand: fix build error when CONFIG_MTD_ONENAND_OMAP2=n
Pull ACPI & Power Management patches from Len Brown.
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
acpi_pad: fix power_saving thread deadlock
ACPI video: Still use ACPI backlight control if _DOS doesn't exist
ACPI, APEI, Avoid too much error reporting in runtime
ACPI: Add a quirk for "AMILO PRO V2030" to ignore the timer overriding
ACPI: Remove one board specific WARN when ignoring timer overriding
ACPI: Make acpi_skip_timer_override cover all source_irq==0 cases
ACPI, x86: fix Dell M6600 ACPI reboot regression via DMI
ACPI sysfs.c strlen fix
Here is a number of printk() fixes, specifically a few reported by the
crazy blog program that ships in SUSE releases (that's "boot log" and
not "web log", it predates the general "blog" terminology by many
years), and the restoration of the continuation line functionality
reported by Stephen and others. Yes, the changes seem a bit big this
late in the cycle, but I've been beating on them for a while now, and
Stephen has even optimized it a bit, so all looks good to me.
The other change in here is a Documentation update for the stable kernel
rules describing how some distro patches should be backported, to
hopefully drive a bit more response from the distros to the stable
kernel releases.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver Core fixes from Greg Kroah-Hartman:
"Here is a number of printk() fixes, specifically a few reported by the
crazy blog program that ships in SUSE releases (that's "boot log" and
not "web log", it predates the general "blog" terminology by many
years), and the restoration of the continuation line functionality
reported by Stephen and others. Yes, the changes seem a bit big this
late in the cycle, but I've been beating on them for a while now, and
Stephen has even optimized it a bit, so all looks good to me.
The other change in here is a Documentation update for the stable
kernel rules describing how some distro patches should be backported,
to hopefully drive a bit more response from the distros to the stable
kernel releases.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'driver-core-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
printk: Optimize if statement logic where newline exists
printk: flush continuation lines immediately to console
syslog: fill buffer with more than a single message for SYSLOG_ACTION_READ
Revert "printk: return -EINVAL if the message len is bigger than the buf size"
printk: fix regression in SYSLOG_ACTION_CLEAR
stable: Allow merging of backports for serious user-visible performance issues
The acpi_pad driver can get stuck in destroy_power_saving_task()
waiting for kthread_stop() to stop a power_saving thread. The problem
is that the isolated_cpus_lock mutex is owned when
destroy_power_saving_task() calls kthread_stop(), which waits for a
power_saving thread to end, and the power_saving thread tries to
acquire the isolated_cpus_lock when it calls round_robin_cpu(). This
patch fixes the issue by making round_robin_cpu() use its own mutex.
https://bugzilla.kernel.org/show_bug.cgi?id=42981
Cc: stable@vger.kernel.org
Signed-off-by: Stuart Hayes <Stuart_Hayes@Dell.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This fixes a regression in 3.4-rc1 caused by commit
ea9f8856bd
(ACPI video: Harden video bus adding.)
Some platforms don't have _DOS control method, but the ACPI
backlight still works.
We should not invoke _DOS for these platforms.
https://bugzilla.kernel.org/show_bug.cgi?id=43168
Cc: Igor Murzov <intergalactic.anonymous@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
* Fix for a bug in async suspend error code path causing parents to wait
forever for their children in case of a suspend error from Mandeep Singh
Baines (-stable metarial).
* Fix for a suspend regression related to earlier changes in the ACPI
cpuidle driver from Deepthi Dharwar.
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Merge tag 'pm-for-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael J. Wysocki:
* Fix for a bug in async suspend error code path causing parents to
wait forever for their children in case of a suspend error from
Mandeep Singh Baines (-stable metarial).
* Fix for a suspend regression related to earlier changes in the ACPI
cpuidle driver from Deepthi Dharwar.
* tag 'pm-for-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / ACPI: Fix suspend/resume regression caused by cpuidle cleanup.
PM / Sleep: Prevent waiting forever on asynchronous suspend after abort
In reviewing Kay's fix up patch: "printk: Have printk() never buffer its
data", I found two if statements that could be combined and optimized.
Put together the two 'cont.len && cont.owner == current' if statements
into a single one, and check if we need to call cont_add(). This also
removes the unneeded double cont_flush() calls.
Link: http://lkml.kernel.org/r/1340869133.876.10.camel@mop
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull powerpc fixes from Benjamin Herrenschmidt:
"Here are a few powerpc fixes. Arguably some of this should have come
to you earlier but I'm only just catching up after my medical leave.
Mostly these fixes regressions, a couple are long standing bugs."
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/pseries: Fix software invalidate TCE
powerpc: check_and_cede_processor() never cedes
powerpc/ftrace: Do not trace restore_interrupts()
powerpc: Fix Section mismatch warnings in prom_init.c
ppc64: fix missing to check all bits of _TIF_USER_WORK_MASK in preempt
powerpc: Fix uninitialised error in numa.c
powerpc: Fix BPF_JIT code to link with multiple TOCs
Pull x86 fixes from Ingo Molnar.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, cpufeature: Remove stray %s, add -w to mkcapflags.pl
x86, cpufeature: Catch duplicate CPU feature strings
x86, cpufeature: Rename X86_FEATURE_DTS to X86_FEATURE_DTHERM
x86: Fix kernel-doc warnings
x86, compat: Use test_thread_flag(TIF_IA32) in compat signal delivery
Pull oprofile fixlet from Ingo Molnar.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
oprofile: perf: use NR_CPUS instead or nr_cpumask_bits for static array
Pull RCU fix from Ingo Molnar.
Fixes a bug introduced in this merge window by commit b1420f1c ("Make
rcu_barrier() less disruptive")
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcu: Stop rcu_do_batch() from multiplexing the "count" variable
Continuation lines are buffered internally, intended to merge the
chunked printk()s into a single record, and to isolate potentially
racy continuation users from usual terminated line users.
This though, has the effect that partial lines are not printed to
the console in the moment they are emitted. In case the kernel
crashes in the meantime, the potentially interesting printed
information would never reach the consoles.
Here we share the continuation buffer with the console copy logic,
and partial lines are always immediately flushed to the available
consoles. They are still buffered internally to improve the
readability and integrity of the messages and minimize the amount
of needed record headers to store.
Signed-off-by: Kay Sievers <kay@vrfy.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The following added support for powernv but broke pseries/BML:
1f1616e powerpc/powernv: Add TCE SW invalidation support
TCE_PCI_SW_INVAL was split into FREE and CREATE flags but the tests in
the pseries code were not updated to reflect this.
Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: stable@kernel.org [v3.3+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit f948501b36 ("Make hard_irq_disable() actually hard-disable
interrupts") caused check_and_cede_processor to stop working.
->irq_happened will never be zero right after a hard_irq_disable
so the compiler removes the call to cede_processor completely.
The bug was introduced back in the lazy interrupt handling rework
of 3.4 but was hidden until recently because hard_irq_disable did
nothing.
This issue will eventually appear in 3.4 stable since the
hard_irq_disable fix is marked stable, so mark this one for stable
too.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As I was adding code that affects all archs, I started testing function
tracer against PPC64 and found that it currently locks up with 3.4
kernel. I figured it was due to tracing a function that shouldn't be, so
I went through the following process to bisect to find the culprit:
cat /debug/tracing/available_filter_functions > t
num=`wc -l t`
sed -ne "1,${num}p" t > t1
let num=num+1
sed -ne "${num},$p" t > t2
cat t1 > /debug/tracing/set_ftrace_filter
echo function /debug/tracing/current_tracer
<failed? bisect t1, if not bisect t2>
It finally came down to this function: restore_interrupts()
I'm not sure why this locks up the system. It just seems to prevent
scheduling from occurring. Interrupts seem to still work, as I can ping
the box. But all user processes freeze.
When restore_interrupts() is not traced, function tracing works fine.
Cc: stable@kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patches tries to fix a couple of Section mismatch warnings like
following one:
WARNING: arch/powerpc/kernel/built-in.o(.text+0x2923c): Section mismatch
in reference from the function .prom_query_opal() to the
function .init.text:.call_prom()
The function .prom_query_opal() references
the function __init .call_prom().
This is often because .prom_query_opal lacks a __init
annotation or the annotation of .call_prom is wrong.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In entry_64.S version of ret_from_except_lite, you'll notice that
in the !preempt case, after we've checked MSR_PR we test for any
TIF flag in _TIF_USER_WORK_MASK to decide whether to go to do_work
or not. However, in the preempt case, we do a convoluted trick to
test SIGPENDING only if PR was set and always test NEED_RESCHED ...
but we forget to test any other bit of _TIF_USER_WORK_MASK !!! So
that means that with preempt, we completely fail to test for things
like single step, syscall tracing, etc...
This should be fixed as the following path:
- Test PR. If not set, go to resume_kernel, else continue.
- If go resume_kernel, to do that original do_work.
- If else, then always test for _TIF_USER_WORK_MASK to decide to do
that original user_work, else restore directly.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
chroma_defconfig currently gives me this with gcc 4.6:
arch/powerpc/mm/numa.c:638:13: error: 'dm' may be used uninitialized in this function [-Werror=uninitialized]
It's a bogus warning/error since of_get_drconf_memory() only writes it
anyway.
Signed-off-by: Michael Neuling <mikey@neuling.org>
cc: <stable@kernel.org> [v3.3+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If the kernel is big enough (eg. allyesconfig), the linker may need to
switch TOCs when calling from the BPF JIT code out to the external
helpers (skb_copy_bits() & bpf_internal_load_pointer_neg_helper()).
In order to do that we need to leave space after the bl for the linker
to insert a reload of our TOC pointer.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull watchdog fixes from Wim Van Sebroeck:
"This fixes:
- the WDIOC_GETSTATUS return value
- the unregister of all NMI events on exit
- the loading of the iTCO_wdt driver after the conversion to the
lpc_ich mfd model."
* git://www.linux-watchdog.org/linux-watchdog:
watchdog: core: fix WDIOC_GETSTATUS return value
watchdog: hpwdt: Unregister NMI events on exit.
watchdog: iTCO_wdt: add platform driver module alias
Pull UDF fixes from Jan Kara:
"Make UDF more robust in presence of corrupted filesystem"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
udf: Fortify loading of sparing table
udf: Avoid run away loop when partition table length is corrupted
udf: Use 'ret' instead of abusing 'i' in udf_load_logicalvol()
'IS_ENABLED()' macro usage: should be 'IS_ENABLED(CONFIG_DEBUG_FS)',
but we had 'IS_ENABLED(DEBUG_FS)'. Also fix incorrect assertion.
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Merge tag 'upstream-3.5-rc5' of git://git.infradead.org/linux-ubifs
Pull ubi/ubifs fixes from Artem Bityutskiy:
"Fix the debugfs regression - we never enable it because incorrect
'IS_ENABLED()' macro usage: should be 'IS_ENABLED(CONFIG_DEBUG_FS)',
but we had 'IS_ENABLED(DEBUG_FS)'. Also fix incorrect assertion."
* tag 'upstream-3.5-rc5' of git://git.infradead.org/linux-ubifs:
UBI: correct usage of IS_ENABLED()
UBIFS: correct usage of IS_ENABLED()
UBIFS: fix assertion
In commit 7a87982420 we added
a wrapper for the WDIOC_GETSTATUS ioctl call. The code results
however in a different behaviour: it returns an error if the
driver doesn't support the status operation. This is not
according to the API that says that when we don't support
the status operation, that we just should return a 0 value.
Only when the device isn't there anymore, we should return an
error.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This patch is to unregister for NMI events upon exit. Also we are now
making the default setting for allow_kdump enabled.
Signed-off-by: Thomas Mingarelli <thomas.mingarelli@hp.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
The recent conversion of iTCO_wdt resulted in the driver no longer
getting loaded automatically, since it no longer has a
MODULE_DEVICE_TABLE() included. As the lpc_ich driver now creates a
platform device, auto-loading can easily be done by having a respective
module alias in place.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Aaron Sierra <asierra@xes-inc.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Pull drm fixes from Dave Airlie:
"Nearly all intel, one missing license header in nouveau, nothing
majorly earth shattering."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
Revert "drm/i915: allow PCH PWM override on IVB"
drm/nouveau: add license header to prime.
drm/i915: Fix eDP blank screen after S3 resume on HP desktops
drm/i915: rip out the PM_IIR WARN
Paul E. McKenney