Every so often, after code shuffles, I need to go through and unbitrot
the Lguest Journey (see drivers/lguest/README). Since we now use RCU in
a simple form in one place I took the opportunity to expand that explanation.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
I don't really notice it (except to begrudge the extra vertical
space), but Ingo does. And he pointed out that one excuse of lguest
is as a teaching tool, it should set a good example.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@redhat.com>
1d589bb16b "Add serial number support
for virtio_blk, V4a" extended 'struct virtio_blk_config' to 536 bytes.
Lguest and S/390 both use an 8 bit value for the feature length, and
this change broke them (if the code is naive).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: John Cooper <john.cooper@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
commit d6580a9f15 ("kexec: sysrq: simplify
sysrq-c handler") changed the behavior of sysrq-c to unconditional
dereference of NULL pointer. So in cases with CONFIG_KEXEC, where
crash_kexec() was directly called from sysrq-c before, now it can be said
that a step of "real oops" was inserted before starting kdump.
However, in contrast to oops via SysRq-c from keyboard which results in
panic due to in_interrupt(), oops via "echo c > /proc/sysrq-trigger" will
not become panic unless panic_on_oops=1. It means that even if dump is
properly configured to be taken on panic, the sysrq-c from proc interface
might not start crashdump while the sysrq-c from keyboard can start
crashdump. This confuses traditional users of kdump, i.e. people who
expect sysrq-c to do common behavior in both of the keyboard and proc
interface.
This patch brings the keyboard and proc interface behavior of sysrq-c in
line, by forcing panic_on_oops=1 before oops in sysrq-c handler.
And some updates in documentation are included, to clarify that there is
no longer dependency with CONFIG_KEXEC, and that now the system can just
crash by sysrq-c if no dump mechanism is configured.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Brayan Arraes <brayan@yack.com.br>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The original text suggested that sysfs is mandatory and always
compiled in the kernel.
Signed-off-by: Lucian Adrian Grijincu <lgrijincu@ixiacom.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Fix mute control with some ALC262 models
ALSA: snd_usb_caiaq: add support for Audio2DJ
ALSA: pcm - Fix hwptr buffer-size overlap bug
ALSA: pcm - Fix warnings in debug loggings
ALSA: pcm - Add logging of hwptr updates and interrupt updates
ASoC: tlv320aic3x: Enable PLL when not bypassed
ALSA: hda - Restore GPIO1 properly at resume with AD1984A
ALSA: ctxfi - Fix uninitialized error checks
ALSA: hda - Use snprintf() to be safer
ALSA: usb-audio - Volume control quirk for QuickCam E 3500
ALSA: pcm - Fix regressions with VMware
Webcams in general don't have eeprom. So, the sensor hint code should be
called to properly detect what sensor is inside.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Added the logging functionality to xrun_debug to record the hwptr
updates via snd_pcm_update_hw_ptr() and snd_pcm_update_hwptr_interrupt(),
corresponding to 16 and 8, respectively.
For example,
# echo 9 > /proc/asound/card0/pcm0p/xrun_debug
will record the position and other parameters at each period interrupt
together with the normal XRUN debugging.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (37 commits)
sky2: Avoid races in sky2_down
drivers/net/mlx4: Adjust constant
drivers/net: Move a dereference below a NULL test
drivers/net: Move a dereference below a NULL test
connector: maintainer/mail update.
USB host CDC Phonet network interface driver
macsonic, jazzsonic: fix oops on module unload
macsonic: move probe function to .devinit.text
can: switch carrier on if device was stopped while in bus-off state
can: restart device even if dev_alloc_skb() fails
can: sja1000: remove duplicated includes
New device ID for sc92031 [1088:2031]
3c589_cs: re-initialize the multicast in the tc589_reset
Fix error return for setsockopt(SO_TIMESTAMPING)
netxen: fix thermal check and shutdown
netxen: fix deadlock on dev close
netxen: fix context deletion sequence
net: Micrel KS8851 SPI network driver
tcp: Use correct peer adr when copying MD5 keys
tcp: Fix MD5 signature checking on IPv4 mapped sockets
...
The kernel has used a stale email address of Andreas for a few years.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-sched:
sched: Fix bug in SCHED_IDLE interaction with group scheduling
sched: Fix rt_rq->pushable_tasks initialization in init_rt_rq()
sched: Reset sched stats on fork()
sched_rt: Fix overload bug on rt group scheduling
sched: Documentation/sched-rt-group: Fix style issues & bump version
When a slab cache uses SLAB_DESTROY_BY_RCU, we must be careful when allocating
objects, since slab allocator could give a freed object still used by lockless
readers.
In particular, nf_conntrack RCU lookups rely on ct->tuplehash[xxx].hnnode.next
being always valid (ie containing a valid 'nulls' value, or a valid pointer to next
object in hash chain.)
kmem_cache_zalloc() setups object with NULL values, but a NULL value is not valid
for ct->tuplehash[xxx].hnnode.next.
Fix is to call kmem_cache_alloc() and do the zeroing ourself.
As spotted by Patrick, we also need to make sure lookup keys are committed to
memory before setting refcount to 1, or a lockless reader could get a reference
on the old version of the object. Its key re-check could then pass the barrier.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
FIX prototypes for show & store method in struct driver_attribute
Signed-off-by: vibi sreenivasan <vibi_sreenivasan@cms.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
exception.txt only explains the code on x86, so it's better to
move it into Documentation/x86 directory.
And also rename it to exception-tables.txt which looks much
more reasonable.
This patch is on top of the previous one.
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update Documentation/exception.txt.
Remove trailing whitespaces in it.
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'core-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
dma-debug: Fix the overlap() function to be correct and readable
oprofile: reset bt_lost_no_mapping with other stats
x86/oprofile: rename kernel parameter for architectural perfmon to arch_perfmon
signals: declare sys_rt_tgsigqueueinfo in syscalls.h
rcu: Mark Hierarchical RCU no longer experimental
dma-debug: Put all hash-chain locks into the same lock class
dma-debug: fix off-by-one error in overlap function
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (29 commits)
cxgb3: Fix crash caused by stashing wrong netdev_queue
ixgbe: Fix coexistence of FCoE and Flow Director in 82599
memory barrier: adding smp_mb__after_lock
net: adding memory barrier to the poll and receive callbacks
netpoll: Fix carrier detection for drivers that are using phylib
includecheck fix: include/linux, rfkill.h
p54: tx refused but queue active
Atheros Kconfig needs to be dependent on WLAN_80211
mac80211: fix docbook
mac80211_hwsim: avoid NULL access
ssb: Add support for 4318E
b43: Add support for 4318E
zd1211rw: adding SONY IFU-WLM2 (054c:0257) as a zd1211b device
zd1211rw: 07b8:6001 is a ZD1211B
r6040: bump driver version to 0.24 and date to 08 July 2009
r6040: restore MIER register correctly when IRQ line is shared
ipv4: Fix fib_trie rebalancing, part 4 (root thresholds)
davinci_emac: fix kernel oops when changing MAC address while interface is down
igb: set lan id prior to configuring phy
mac80211: minstrel: avoid accessing negative indices in rix_to_ndx()
...
The short name of the achitecture is 'arch_perfmon'. This patch
changes the kernel parameter to use this name.
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
These two functions no longer exist in mac80211,
so trying to insert them generates warnings in
the document.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
lock_policy_rwsem_* and unlock_policy_rwsem_* routines in cpufreq.c are
currently exported to drivers. Improper use of those locks can
result in deadlocks and it is better to keep the locks localized.
Two previous in-kernel users of these interfaces (ondemand and conservative),
do not use this interfaces any more. Schedule them for removal.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
The extraction routine for the MPC718 "firmware" had 2 bugs in it, where one
bug masked the effect of the other. The loop iteration should have set
$prevlen = $currlen at the end of the loop, and the if() check should have used
&& instead of || for deciding if the firmware length is reasonable.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This webcam uses a em2710 chipset, that identifies itself as em2820,
plus a mt9v011 sensor, and a DY-301P lens.
It needs a few different initializations than a normal em28xx device.
Thanks to Hans de Goede <hdegoede@redhat.com> and Douglas Landgraf
<dougsland@redhat.com> for providing the acces for the webcam during
this weekend, I could make a patch for it while returning back from
FISL/Fudcom LATAM 2009.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Add routine to support extracting the MT352 DVB-T demodulator initialization
sequence for Yuan MPC718 cards for use by the cx18 driver.
This routine uses a hueristic for extracting a good sequence. It should work
on all different versions of the "yuanrap.sys" file, given the way the MT352
tuning sequences are stored in all versions of that file I have seen so far.
However, the current patch simply looks for one specific archive URL.
Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Andre Noll <maan@systemlinux.org>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* 'kmemleak' of git://linux-arm.org/linux-2.6:
kmemleak: Inform kmemleak about pid_hash
kmemleak: Do not warn if an unknown object is freed
kmemleak: Do not report new leaked objects if the scanning was stopped
kmemleak: Slightly change the policy on newly allocated objects
kmemleak: Do not trigger a scan when reading the debug/kmemleak file
kmemleak: Simplify the reports logged by the scanning thread
kmemleak: Enable task stacks scanning by default
kmemleak: Allow the early log buffer to be configurable.
By writing a tasks's pid to the file, a process adds that task to that
cgroup/cpuset. But to add a cpu/mem to a cpuset, the new list of cpus
should be written to the cpuset.mems file which would replace the old list
of cpus. Make this clearer in the documentation.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add two new spi_device.mode bits to accomodate more protocol options, and
pass them through to usermode drivers:
* SPI_NO_CS ... a second 3-wire variant, where the chipselect
line is removed instead of a data line; transfers are still
full duplex.
This obviously has STRONG protocol implications since the
chipselect transitions can't be used to synchronize state
transitions with the SPI master.
* SPI_READY ... defines open drain signal that's pulled low
to pause the clock. This defines a 5-wire variant (normal
4-wire SPI plus READY) and two 4-wire variants (READY plus
each of the 3-wire flavors).
Such hardware flow control can be a big win. There are ADC
converters and flash chips that expose READY signals, but not
many host controllers support it today.
The spi_bitbang code should be changed to use SPI_NO_CS instead of its
current nonportable hack. That's a mode most hardware can easily support
(unlike SPI_READY).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: "Paulraj, Sandeep" <s-paulraj@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commonly available versions of cp and tar don't work well with special
files created using seq_file. Mention this problem in the gcov
documentation and update the helper script example to work around these
problems.
Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
sound: OSS: mpu401, fix deadlock
ALSA: hda - Add missing initializations for ALC268 and ALC269
ALSA: cmi8330: fix MPU-401 PnP init copy&paste bug
ALSA: hda - Line In for Acer Inspire 6530G model
sound: oxygen: make mic volume control mono
MAINTAINERS: Add entry for twl4030 series soc codec driver
ALSA: lx6464es - configure ethersound io channels
sound: Use PCI_VDEVICE for CREATIVE and ECTIVA
sound: Use PCI_VDEVICE
ALSA: hda - Use model=acer-aspire-6530g for Acer Aspire 6930G
ALSA: hda - Fix acer-aspire-6530g model quirk
ALSA: hda - Add pin-sense trigger when needed for Realtek codecs
ALSA: hda - Fix support for Samsung P50 with AD1986A codec
ALSA: hda - Generalize the pin-detect quirk for Lenovo N100
ALSA: hda - Simplify AD1986A mixer definitions
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, delay: tsc based udelay should have rdtsc_barrier
x86, setup: correct include file in <asm/boot.h>
x86, setup: Fix typo "CONFIG_x86_64" in <asm/boot.h>
x86, mce: percpu mcheck_timer should be pinned
x86: Add sysctl to allow panic on IOCK NMI error
x86: Fix uv bau sending buffer initialization
x86, mce: Fix mce resume on 32bit
x86: Move init_gbpages() to setup_arch()
x86: ensure percpu lpage doesn't consume too much vmalloc space
x86: implement percpu_alloc kernel parameter
x86: fix pageattr handling for lpage percpu allocator and re-enable it
x86: reorganize cpa_process_alias()
x86: prepare setup_pcpu_lpage() for pageattr fix
x86: rename remap percpu first chunk allocator to lpage
x86: fix duplicate free in setup_pcpu_remap() failure path
percpu: fix too lazy vunmap cache flushing
x86: Set cpu_llc_id on AMD CPUs
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
ftrace: Fix the output of profile
ring-buffer: Make it generally available
ftrace: Remove duplicate newline
tracing: Fix trace_buf_size boot option
ftrace: Fix t_hash_start()
ftrace: Don't manipulate @pos in t_start()
ftrace: Don't increment @pos in g_start()
tracing: Reset iterator in t_start()
trace_stat: Don't increment @pos in seq start()
tracing_bprintk: Don't increment @pos in t_start()
tracing/events: Don't increment @pos in s_start()
* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
leds: Futher document blink_set
leds: Add options to have GPIO LEDs start on or keep their state
leds: LED driver for National Semiconductor LP3944 Funlight Chip
leds: pca9532 - Indent using tabs, not spaces.
leds: Remove an orphan Kconfig entry
leds: Further document parameters for blink_set()
leds: alix-leds2 fixed for Award BIOS
leds: leds-gpio - fix a section mismatch
leds: add the sysfs interface into the leds-bd2802 driver for changing wave pattern and led current.
leds: change the license information
leds: fix led-bd2802 errors while resuming
Since there is a kernel thread for automatically scanning the memory, it
makes sense for the debug/kmemleak file to only show its findings. This
patch also adds support for "echo scan > debug/kmemleak" to trigger an
intermediate memory scan and eliminates the kmemleak_mutex (scan_mutex
covers all the cases now).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Because of false positives, the memory scanning thread may print too
much information. This patch changes the scanning thread to only print
the number of newly suspected leaks. Further information can be read
from the /sys/kernel/debug/kmemleak file.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(feature suggested by Sergey Senozhatsky)
Kmemleak needs to track all the memory allocations but some of these
happen before kmemleak is initialised. These are stored in an internal
buffer which may be exceeded in some kernel configurations. This patch
adds a configuration option with a default value of 400 and also removes
the stack dump when the early log buffer is exceeded.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@mail.by>
This reverts commit 9e9f46c44e.
Quoting from the commit message:
"At this point, it seems to solve more problems than it causes, so let's
try using it by default. It's an easy revert if it ends up causing
trouble."
And guess what? The _CRS code causes trouble.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (48 commits)
dm mpath: change to be request based
dm: disable interrupt when taking map_lock
dm: do not set QUEUE_ORDERED_DRAIN if request based
dm: enable request based option
dm: prepare for request based option
dm raid1: add userspace log
dm: calculate queue limits during resume not load
dm log: fix create_log_context to use logical_block_size of log device
dm target:s introduce iterate devices fn
dm table: establish queue limits by copying table limits
dm table: replace struct io_restrictions with struct queue_limits
dm table: validate device logical_block_size
dm table: ensure targets are aligned to logical_block_size
dm ioctl: support cookies for udev
dm: sysfs add suspended attribute
dm table: improve warning message when devices not freed before destruction
dm mpath: add service time load balancer
dm mpath: add queue length load balancer
dm mpath: add start_io and nr_bytes to path selectors
dm snapshot: use barrier when writing exception store
...
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (72 commits)
asus-laptop: remove EXPERIMENTAL dependency
asus-laptop: use pr_fmt and pr_<level>
eeepc-laptop: cpufv updates
eeepc-laptop: sync eeepc-laptop with asus_acpi
asus_acpi: Deprecate in favor of asus-laptop
acpi4asus: update MAINTAINER and KConfig links
asus-laptop: platform dev as parent for led and backlight
eeepc-laptop: enable camera by default
ACPI: Rename ACPI processor device bus ID
acerhdf: Acer Aspire One fan control
ACPI: video: DMI workaround broken Acer 7720 BIOS enabling display brightness
ACPI: run ACPI device hot removal in kacpi_hotplug_wq
ACPI: Add the reference count to avoid unloading ACPI video bus twice
ACPI: DMI to disable Vista compatibility on some Sony laptops
ACPI: fix a deadlock in hotplug case
Show the physical device node of backlight class device.
ACPI: pdc init related memory leak with physical CPU hotplug
ACPI: pci_root: remove unused dev/fn information
ACPI: pci_root: simplify list traversals
ACPI: pci_root: use driver data rather than list lookup
...
The rules for locking in many superblock operations has changed
significantly, so update the documentation for it. Also correct some
older updates and ommissions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Samsung P50 requires the HP auto-muting unlike other Samsung models.
Added a new model=samsung-p50 to support this.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
We should be able to specify [KMG] when setting trace_buf_size
boot option, as documented in kernel-parameters.txt
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A41F2DB.4020102@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There already is a "default-on" trigger but there are problems with it.
For one, it's a inefficient way to do it and requires led trigger support
to be compiled in.
But the real reason is that is produces a glitch on the LED. The GPIO is
allocate with the LED *off*, then *later* when the trigger runs it is
turned back on. If the LED was already on via the GPIO's reset default or
action of the firmware, this produces a glitch where the LED goes from on
to off to on. While normally this is fast enough that it wouldn't be
noticeable to a human observer, there are still serious problems.
One is that there may be something else on the GPIO line, like a hardware
alarm or watchdog, that is fast enough to notice the glitch.
Another is that the kernel may panic before the LED is turned back on, thus
hanging with the LED in the wrong state. This is not just speculation, but
actually happened to me with an embedded system that has an LED which
should turn off when the kernel finishes booting, which was left in the
incorrect state due to a bug in the OF LED binding code.
We also let GPIO LEDs get their initial value from whatever the current
state of the GPIO line is. On some systems the LEDs are put into some
state by the firmware or hardware before Linux boots, and it is desired to
have them keep this state which is otherwise unknown to Linux.
This requires that the underlying GPIO driver support reading the value of
output GPIOs. Some drivers support this and some do not.
The platform device binding gains a field in the platform data
"default_state" that controls this. There are three constants defined to
select from on, off, or keeping the current state. The OpenFirmware
binding uses a property named "default-state" that can be set to "on",
"off", or "keep". The default if the property isn't present is off.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
