Digging into some assembly file in order to get information about the
kuser helpers is not that convivial. Let's move that information to
a better formatted file in Documentation/arm/ and improve on it a bit.
Thanks to Dave Martin <dave.martin@linaro.org> for the initial cleanup and
clarifications.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Dave Martin <dave.martin@linaro.org>
Some USB mass-storage devices have bugs that cause them not to handle
the first READ(10) command they receive correctly. The Corsair
Padlock v2 returns completely bogus data for its first read (possibly
it returns the data in encrypted form even though the device is
supposed to be unlocked). The Feiya SD/SDHC card reader fails to
complete the first READ(10) command after it is plugged in or after a
new card is inserted, returning a status code that indicates it thinks
the command was invalid, which prevents the kernel from retrying the
read.
Since the first read of a new device or a new medium is for the
partition sector, the kernel is unable to retrieve the device's
partition table. Users have to manually issue an "hdparm -z" or
"blockdev --rereadpt" command before they can access the device.
This patch (as1470) works around the problem. It adds a new quirk
flag, US_FL_INVALID_READ10, indicating that the first READ(10) should
always be retried immediately, as should any failing READ(10) commands
(provided the preceding READ(10) command succeeded, to avoid getting
stuck in a loop). The patch also adds appropriate unusual_devs
entries containing the new flag.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Sven Geggus <sven-usbst@geggus.net>
Tested-by: Paul Hartman <paul.hartman+linux@gmail.com>
CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
CC: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* git://git.infradead.org/iommu-2.6:
intel-iommu: Fix off-by-one in RMRR setup
intel-iommu: Add domain check in domain_remove_one_dev_info
intel-iommu: Remove Host Bridge devices from identity mapping
intel-iommu: Use coherent DMA mask when requested
intel-iommu: Dont cache iova above 32bit
intel-iommu: Speed up processing of the identity_mapping function
intel-iommu: Check for identity mapping candidate using system dma mask
intel-iommu: Only unlink device domains from iommu
intel-iommu: Enable super page (2MiB, 1GiB, etc.) support
intel-iommu: Flush unmaps at domain_exit
intel-iommu: Remove obsolete comment from detect_intel_iommu
intel-iommu: fix VT-d PMR disable for TXT on S3 resume
There are no externally-visible changes with this. In the loop in the
internal __domain_mapping() function, we simply detect if we are mapping:
- size >= 2MiB, and
- virtual address aligned to 2MiB, and
- physical address aligned to 2MiB, and
- on hardware that supports superpages.
(and likewise for larger superpages).
We automatically use a superpage for such mappings. We never have to
worry about *breaking* superpages, since we trust that we will always
*unmap* the same range that was mapped. So all we need to do is ensure
that dma_pte_clear_range() will also cope with superpages.
Adjust pfn_to_dma_pte() to take a superpage 'level' as an argument, so
it can return a PTE at the appropriate level rather than always
extending the page tables all the way down to level 1. Again, this is
simplified by the fact that we should never encounter existing small
pages when we're creating a mapping; any old mapping that used the same
virtual range will have been entirely removed and its obsolete page
tables freed.
Provide an 'intel_iommu=sp_off' argument on the command line as a
chicken bit. Not that it should ever be required.
==
The original commit seen in the iommu-2.6.git was Youquan's
implementation (and completion) of my own half-baked code which I'd
typed into an email. Followed by half a dozen subsequent 'fixes'.
I've taken the unusual step of rewriting history and collapsing the
original commits in order to keep the main history simpler, and make
life easier for the people who are going to have to backport this to
older kernels. And also so I can give it a more coherent commit comment
which (hopefully) gives a better explanation of what's going on.
The original sequence of commits leading to identical code was:
Youquan Song (3):
intel-iommu: super page support
intel-iommu: Fix superpage alignment calculation error
intel-iommu: Fix superpage level calculation error in dma_pfn_level_pte()
David Woodhouse (4):
intel-iommu: Precalculate superpage support for dmar_domain
intel-iommu: Fix hardware_largepage_caps()
intel-iommu: Fix inappropriate use of superpages in __domain_mapping()
intel-iommu: Fix phys_pfn in __domain_mapping for sglist pages
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86: (43 commits)
acer-wmi: support integer return type from WMI methods
msi-laptop: fix section mismatch in reference from the function load_scm_model_init
acer-wmi: support to set communication device state by new wmid method
acer-wmi: allow 64-bits return buffer from WMI methods
acer-wmi: check the existence of internal 3G device when set capability
platform/x86:delete two unused variables
support wlan hotkey on Acer Travelmate 5735Z
platform-x86: intel_mid_thermal: Fix memory leak
platform/x86: Fix Makefile for intel_mid_powerbtn
platform/x86: Simplify intel_mid_powerbtn
acer-wmi: Delete out-of-date documentation
acerhdf: Clean up includes
acerhdf: Drop pointless dependency on THERMAL_HWMON
acer-wmi: Update MAINTAINERS
wmi: Orphan ACPI-WMI driver
tc1100-wmi: Orphan driver
acer-wmi: does not allow negative number set to initial device state
platform/oaktrail: ACPI EC Extra driver for Oaktrail
thinkpad_acpi: Convert printks to pr_<level>
thinkpad_acpi: Correct !CONFIG_THINKPAD_ACPI_VIDEO warning
...
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
ACPI EC: remove redundant code
ACPI: Add D3 cold state
ACPI: processor: fix processor_physically_present in UP kernel
ACPI: Split out custom_method functionality into an own driver
ACPI: Cleanup custom_method debug stuff
ACPI EC: enable MSI workaround for Quanta laptops
ACPICA: Update to version 20110413
ACPICA: Execute an orphan _REG method under the EC device
ACPICA: Move ACPI_NUM_PREDEFINED_REGIONS to a more appropriate place
ACPICA: Update internal address SpaceID for DataTable regions
ACPICA: Add more methods eligible for NULL package element removal
ACPICA: Split all internal Global Lock functions to new file - evglock
ACPI: EC: add another DMI check for ASUS hardware
ACPI EC: remove dead code
ACPICA: Fix code divergence of global lock handling
ACPICA: Use acpi_os_create_lock interface
ACPI: osl, add acpi_os_create_lock interface
ACPI:Fix goto flows in thermal-sys
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param
x86 idle: deprecate "no-hlt" cmdline param
x86 idle APM: deprecate CONFIG_APM_CPU_IDLE
x86 idle floppy: deprecate disable_hlt()
x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it
x86 idle: clarify AMD erratum 400 workaround
idle governor: Avoid lock acquisition to read pm_qos before entering idle
cpuidle: menu: fixed wrapping timers at 4.294 seconds
mwait_idle() is a C1-only idle loop intended to be more efficient
than HLT on SMP hardware that supports it.
But mwait_idle() has been replaced by the more general
mwait_idle_with_hints(), which handles both C1 and deeper C-states.
ACPI uses only mwait_idle_with_hints(), and never uses mwait_idle().
Deprecate mwait_idle() and the "idle=mwait" cmdline param
to simplify the x86 idle code.
After this change, kernels configured with
(!CONFIG_ACPI=n && !CONFIG_INTEL_IDLE=n) when run on hardware
that support MWAIT will simply use HLT. If MWAIT is desired
on those systems, cpuidle and the cpuidle drivers above
can be used.
cc: x86@kernel.org
cc: stable@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
We'd rather that modern machines not check if HLT works on
every entry into idle, for the benefit of machines that had
marginal electricals 15-years ago. If those machines are still running
the upstream kernel, they can use "idle=poll". The only difference
will be that they'll now invoke HLT in machine_hlt().
cc: x86@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
We don't want to export the pm_idle function pointer to modules.
Currently CONFIG_APM_CPU_IDLE w/ CONFIG_APM_MODULE forces us to.
CONFIG_APM_CPU_IDLE is of dubious value, it runs only on 32-bit
uniprocessor laptops that are over 10 years old. It calls into
the BIOS during idle, and is known to cause a number of machines
to fail.
Removing CONFIG_APM_CPU_IDLE and will allow us to stop exporting
pm_idle. Any systems that were calling into the APM BIOS
at run-time will simply use HLT instead.
cc: x86@kernel.org
cc: Jiri Kosina <jkosina@suse.cz>
cc: stable@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
Plan to remove floppy_disable_hlt in 2012, an ancient
workaround with comments that it should be removed.
This allows us to remove clutter and a run-time branch
from the idle code.
WARN_ONCE() on invocation until it is removed.
cc: x86@kernel.org
cc: stable@kernel.org # .39.x
Signed-off-by: Len Brown <len.brown@intel.com>
With /sys/kernel/debug/acpi/custom_method root can write
to arbitrary memory and increase his priveleges, even if
these are restricted.
-> Make this an own debug .config option and warn about the
security issue in the config description.
-> Still keep acpi/debugfs.c which now only creates an empty
/sys/kernel/debug/acpi directory. There might be other
users of it later.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: rui.zhang@intel.com
Signed-off-by: Len Brown <len.brown@intel.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (36 commits)
Cache xattr security drop check for write v2
fs: block_page_mkwrite should wait for writeback to finish
mm: Wait for writeback when grabbing pages to begin a write
configfs: remove unnecessary dentry_unhash on rmdir, dir rename
fat: remove unnecessary dentry_unhash on rmdir, dir rename
hpfs: remove unnecessary dentry_unhash on rmdir, dir rename
minix: remove unnecessary dentry_unhash on rmdir, dir rename
fuse: remove unnecessary dentry_unhash on rmdir, dir rename
coda: remove unnecessary dentry_unhash on rmdir, dir rename
afs: remove unnecessary dentry_unhash on rmdir, dir rename
affs: remove unnecessary dentry_unhash on rmdir, dir rename
9p: remove unnecessary dentry_unhash on rmdir, dir rename
ncpfs: fix rename over directory with dangling references
ncpfs: document dentry_unhash usage
ecryptfs: remove unnecessary dentry_unhash on rmdir, dir rename
hostfs: remove unnecessary dentry_unhash on rmdir, dir rename
hfsplus: remove unnecessary dentry_unhash on rmdir, dir rename
hfs: remove unnecessary dentry_unhash on rmdir, dir rename
omfs: remove unnecessary dentry_unhash on rmdir, dir rneame
udf: remove unnecessary dentry_unhash from rmdir, dir rename
...
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: Start RCU kthreads in TASK_INTERRUPTIBLE state
rcu: Remove waitqueue usage for cpu, node, and boost kthreads
rcu: Avoid acquiring rcu_node locks in timer functions
atomic: Add atomic_or()
Documentation: Add statistics about nested locks
rcu: Decrease memory-barrier usage based on semi-formal proof
rcu: Make rcu_enter_nohz() pay attention to nesting
rcu: Don't do reschedule unless in irq
rcu: Remove old memory barriers from rcu_process_callbacks()
rcu: Add memory barriers
rcu: Fix unpaired rcu_irq_enter() from locking selftests
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (33 commits)
x86: poll waiting for I/OAT DMA channel status
maintainers: add dma engine tree details
dmaengine: add TODO items for future work on dma drivers
dmaengine: Add API documentation for slave dma usage
dmaengine/dw_dmac: Update maintainer-ship
dmaengine: move link order
dmaengine/dw_dmac: implement pause and resume in dwc_control
dmaengine/dw_dmac: Replace spin_lock* with irqsave variants and enable submission from callback
dmaengine/dw_dmac: Divide one sg to many desc, if sg len is greater than DWC_MAX_COUNT
dmaengine/dw_dmac: set residue as total len in dwc_tx_status if status is !DMA_SUCCESS
dmaengine/dw_dmac: don't call callback routine in case dmaengine_terminate_all() is called
dmaengine: at_hdmac: pause: no need to wait for FIFO empty
pch_dma: modify pci device table definition
pch_dma: Support new device ML7223 IOH
pch_dma: Support I2S for ML7213 IOH
pch_dma: Fix DMA setting issue
pch_dma: modify for checkpatch
pch_dma: fix dma direction issue for ML7213 IOH video-in
dmaengine: at_hdmac: use descriptor chaining help function
dmaengine: at_hdmac: implement pause and resume in atc_control
...
Fix up trivial conflict in drivers/dma/dw_dmac.c
Explain what the trailing "/1" on some lock class names of
lock_stat output means.
Reviewed-by: Yong Zhang <yong.zhang0@gmail.com>
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4DD4F6C1.5090701@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.infradead.org/mtd-2.6: (97 commits)
mtd: kill CONFIG_MTD_PARTITIONS
mtd: remove add_mtd_partitions, add_mtd_device and friends
mtd: convert remaining users to mtd_device_register()
mtd: samsung onenand: convert to mtd_device_register()
mtd: omap2 onenand: convert to mtd_device_register()
mtd: txx9ndfmc: convert to mtd_device_register()
mtd: tmio_nand: convert to mtd_device_register()
mtd: socrates_nand: convert to mtd_device_register()
mtd: sharpsl: convert to mtd_device_register()
mtd: s3c2410 nand: convert to mtd_device_register()
mtd: ppchameleonevb: convert to mtd_device_register()
mtd: orion_nand: convert to mtd_device_register()
mtd: omap2: convert to mtd_device_register()
mtd: nomadik_nand: convert to mtd_device_register()
mtd: ndfc: convert to mtd_device_register()
mtd: mxc_nand: convert to mtd_device_register()
mtd: mpc5121_nfc: convert to mtd_device_register()
mtd: jz4740_nand: convert to mtd_device_register()
mtd: h1910: convert to mtd_device_register()
mtd: fsmc_nand: convert to mtd_device_register()
...
Fixed up trivial conflicts in
- drivers/mtd/maps/integrator-flash.c: removed in ARM tree
- drivers/mtd/maps/physmap.c: addition of afs partition probe type
clashing with removal of CONFIG_MTD_PARTITIONS
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (45 commits)
ARM: 6945/1: Add unwinding support for division functions
ARM: kill pmd_off()
ARM: 6944/1: mm: allow ASID 0 to be allocated to tasks
ARM: 6943/1: mm: use TTBR1 instead of reserved context ID
ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7
ARM: 6941/1: cache: ensure MVA is cacheline aligned in flush_kern_dcache_area
ARM: add sendmmsg syscall
ARM: 6863/1: allow hotplug on msm
ARM: 6832/1: mmci: support for ST-Ericsson db8500v2
ARM: 6830/1: mach-ux500: force PrimeCell revisions
ARM: 6829/1: amba: make hardcoded periphid override hardware
ARM: 6828/1: mach-ux500: delete SSP PrimeCell ID
ARM: 6827/1: mach-netx: delete hardcoded periphid
ARM: 6940/1: fiq: Briefly document driver responsibilities for suspend/resume
ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2
ARM: 6914/1: sparsemem: fix highmem detection when using SPARSEMEM
ARM: 6913/1: sparsemem: allow pfn_valid to be overridden when using SPARSEMEM
at91: drop at572d940hf support
at91rm9200: introduce at91rm9200_set_type to specficy cpu package
at91: drop boot_params and PLAT_PHYS_OFFSET
...
* 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs:
Create Documentation/security/, move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/<moved_file> to Documentation/security/<moved_file>.
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6:
[media] v1.88 DM04/QQBOX Move remote to use rc_core dvb-usb-remote
[media] Add missing include guard to header file
[media] Inlined functions should be static
[media] Remove invalid parameter description
[media] cpia2: fix warning about invalid trigraph sequence
[media] s5p-csis: Add missing dependency on PLAT_S5P
[media] gspca/kinect: wrap gspca_debug with GSPCA_DEBUG
[media] fintek-cir: new driver for Fintek LPC SuperIO CIR function
[media] uvcvideo: Connect video devices to media entities
[media] uvcvideo: Register subdevices for each entity
[media] uvcvideo: Register a v4l2_device
[media] add V4L2-PIX-FMT-SRGGB12 & friends to docbook
[media] Documentation/DocBook: Rename media fops xml files
[media] Media DocBook: fix validation errors
[media] wl12xx: g_volatile_ctrl fix: wrong field set
[media] fix kconfig dependency warning for VIDEO_TIMBERDALE
[media] dm1105: GPIO handling added, I2C on GPIO added, LNB control through GPIO reworked
[media] Add support for M-5MOLS 8 Mega Pixel camera ISP
The documentation file for acer-wmi is long out of date, and there's not
much point in keeping it around either.
Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or
anything else, so that the filesystem can track internally if it
needs to push out a transaction for fdatasync or not.
This is just the prototype change with no user for it yet. I plan
to push large XFS changes for the next merge window, and getting
this trivial infrastructure in this window would help a lot to avoid
tree interdependencies.
Also remove incorrect comments that ->dirty_inode can't block. That
has been changed a long time ago, and many implementations rely on it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
supply_regulator_dev (using a struct pointer) has been deprecated in favour
of supply_regulator (using a regulator name) for quite a few releases
now with a warning generated if it is used and there are no current in tree
users so just remove the code.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Now, exe_file is not proc FS dependent, so we can use it to name core
file. So we add %E pattern for core file name cration which extract path
from mm_struct->exe_file. Then it converts slashes to exclamation marks
and pastes the result to the core file name itself.
This is useful for environments where binary names are longer than 16
character (the current->comm limitation). Also where there are binaries
with same name but in a different path. Further in case the binery itself
changes its current->comm after exec.
So by doing (s/$/#/ -- # is treated as git comment):
$ sysctl kernel.core_pattern='core.%p.%e.%E'
$ ln /bin/cat cat45678901234567890
$ ./cat45678901234567890
^Z
$ rm cat45678901234567890
$ fg
^\Quit (core dumped)
$ ls core*
we now get:
core.2434.cat456789012345.!root!cat45678901234567890 (deleted)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Reviewed-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ns_cgroup is an annoying cgroup at the namespace / cgroup frontier and
leads to some problems:
* cgroup creation is out-of-control
* cgroup name can conflict when pids are looping
* it is not possible to have a single process handling a lot of
namespaces without falling in a exponential creation time
* we may want to create a namespace without creating a cgroup
The ns_cgroup was replaced by a compatibility flag 'clone_children',
where a newly created cgroup will copy the parent cgroup values.
The userspace has to manually create a cgroup and add a task to
the 'tasks' file.
This patch removes the ns_cgroup as suggested in the following thread:
https://lists.linux-foundation.org/pipermail/containers/2009-June/018616.html
The 'cgroup_clone' function is removed because it is no longer used.
This is a userspace-visible change. Commit 45531757b4 ("cgroup: notify
ns_cgroup deprecated") (merged into 2.6.27) caused the kernel to emit a
printk warning users that the feature is planned for removal. Since that
time we have heard from XXX users who were affected by this.
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jamal Hadi Salim <hadi@cyberus.ca>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make procs file writable to move all threads by tgid at once.
Add functionality that enables users to move all threads in a threadgroup
at once to a cgroup by writing the tgid to the 'cgroup.procs' file. This
current implementation makes use of a per-threadgroup rwsem that's taken
for reading in the fork() path to prevent newly forking threads within the
threadgroup from "escaping" while the move is in progress.
Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add cgroup subsystem callbacks for per-thread attachment in atomic contexts
Add can_attach_task(), pre_attach(), and attach_task() as new callbacks
for cgroups's subsystem interface. Unlike can_attach and attach, these
are for per-thread operations, to be called potentially many times when
attaching an entire threadgroup.
Also, the old "bool threadgroup" interface is removed, as replaced by
this. All subsystems are modified for the new interface - of note is
cpuset, which requires from/to nodemasks for attach to be globally scoped
(though per-cpuset would work too) to persist from its pre_attach to
attach_task and attach.
This is a pre-patch for cgroup-procs-writable.patch.
Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When configfs_register_subsystem() fails, we unregister too many
subsystems in configfs_example_init. Decrement i by one to not unregister
non-registered subsystem.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I find it very handy to show the average delays in milliseconds.
Example output (on 100 concurrent dd reading sparse files):
CPU count real total virtual total delay total delay average
986 3223509952 3207643301 38863410579 39.415ms
IO count delay total delay average
0 0 0ms
SWAP count delay total delay average
0 0 0ms
RECLAIM count delay total delay average
1059 5131834899 4ms
dd: read=0, write=0, cancelled_write=0
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Mel Gorman <mel@linux.vnet.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Reviewed-by: Satoru Moriya <satoru.moriya@hds.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes
Documentation/accounting/getdelays.c: In function `get_family_id':
Documentation/accounting/getdelays.c:172:14: warning: variable `rc' set but not used [-Wunused-but-set-variable]
Reported-by: "Justin P. Mattock" <justinmattock@gmail.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes
Documentation/accounting/getdelays.c: In function `main':
Documentation/accounting/getdelays.c:436:7: warning: variable `i' set but not used [-Wunused-but-set-variable]
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As declaring counter as volatile is discouraged, it is best not to use it
in sample code as well.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: (28 commits)
Ocfs2: Teach local-mounted ocfs2 to handle unwritten_extents correctly.
ocfs2/dlm: Do not migrate resource to a node that is leaving the domain
ocfs2/dlm: Add new dlm message DLM_BEGIN_EXIT_DOMAIN_MSG
Ocfs2/move_extents: Set several trivial constraints for threshold.
Ocfs2/move_extents: Let defrag handle partial extent moving.
Ocfs2/move_extents: move/defrag extents within a certain range.
Ocfs2/move_extents: helper to calculate the defraging length in one run.
Ocfs2/move_extents: move entire/partial extent.
Ocfs2/move_extents: helpers to update the group descriptor and global bitmap inode.
Ocfs2/move_extents: helper to probe a proper region to move in an alloc group.
Ocfs2/move_extents: helper to validate and adjust moving goal.
Ocfs2/move_extents: find the victim alloc group, where the given #blk fits.
Ocfs2/move_extents: defrag a range of extent.
Ocfs2/move_extents: move a range of extent.
Ocfs2/move_extents: lock allocators and reserve metadata blocks and data clusters for extents moving.
Ocfs2/move_extents: Add basic framework and source files for extent moving.
Ocfs2/move_extents: Adding new ioctl code 'OCFS2_IOC_MOVE_EXT' to ocfs2.
Ocfs2/refcounttree: Publicize couple of funcs from refcounttree.c
Ocfs2: Add a new code 'OCFS2_INFO_FREEFRAG' for o2info ioctl.
Ocfs2: Add a new code 'OCFS2_INFO_FREEINODE' for o2info ioctl.
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem:
xen: cleancache shim to Xen Transcendent Memory
ocfs2: add cleancache support
ext4: add cleancache support
btrfs: add cleancache support
ext3: add cleancache support
mm/fs: add hooks to support cleancache
mm: cleancache core ops functions and config
fs: add field to superblock to support cleancache
mm/fs: cleancache documentation
Fix up trivial conflict in fs/btrfs/extent_io.c due to includes
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
xfs: correctly decrement the extent buffer index in xfs_bmap_del_extent
xfs: check for valid indices in xfs_iext_get_ext and xfs_iext_idx_to_irec
xfs: fix up asserts in xfs_iflush_fork
xfs: do not do pointer arithmetic on extent records
xfs: do not use unchecked extent indices in xfs_bunmapi
xfs: do not use unchecked extent indices in xfs_bmapi
xfs: do not use unchecked extent indices in xfs_bmap_add_extent_*
xfs: remove if_lastex
xfs: remove the unused XFS_BMAPI_RSVBLOCKS flag
xfs: do not discard alloc btree blocks
xfs: add online discard support
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (61 commits)
jbd2: Add MAINTAINERS entry
jbd2: fix a potential leak of a journal_head on an error path
ext4: teach ext4_ext_split to calculate extents efficiently
ext4: Convert ext4 to new truncate calling convention
ext4: do not normalize block requests from fallocate()
ext4: enable "punch hole" functionality
ext4: add "punch hole" flag to ext4_map_blocks()
ext4: punch out extents
ext4: add new function ext4_block_zero_page_range()
ext4: add flag to ext4_has_free_blocks
ext4: reserve inodes and feature code for 'quota' feature
ext4: add support for multiple mount protection
ext4: ensure f_bfree returned by ext4_statfs() is non-negative
ext4: protect bb_first_free in ext4_trim_all_free() with group lock
ext4: only load buddy bitmap in ext4_trim_fs() when it is needed
jbd2: Fix comment to match the code in jbd2__journal_start()
ext4: fix waiting and sending of a barrier in ext4_sync_file()
jbd2: Add function jbd2_trans_will_send_data_barrier()
jbd2: fix sending of data flush on journal commit
ext4: fix ext4_ext_fiemap_cb() to handle blocks before request range correctly
...
(Note: this was reverted, and is now being re-applied in pieces, with
this being the fifth and final piece. See below for the reason that
it is now felt to be safe to re-apply this.)
Commit d09b62d fixed grace-period synchronization, but left some smp_mb()
invocations in rcu_process_callbacks() that are no longer needed, but
sheer paranoia prevented them from being removed. This commit removes
them and provides a proof of correctness in their absence. It also adds
a memory barrier to rcu_report_qs_rsp() immediately before the update to
rsp->completed in order to handle the theoretical possibility that the
compiler or CPU might move massive quantities of code into a lock-based
critical section. This also proves that the sheer paranoia was not
entirely unjustified, at least from a theoretical point of view.
In addition, the old dyntick-idle synchronization depended on the fact
that grace periods were many milliseconds in duration, so that it could
be assumed that no dyntick-idle CPU could reorder a memory reference
across an entire grace period. Unfortunately for this design, the
addition of expedited grace periods breaks this assumption, which has
the unfortunate side-effect of requiring atomic operations in the
functions that track dyntick-idle state for RCU. (There is some hope
that the algorithms used in user-level RCU might be applied here, but
some work is required to handle the NMIs that user-space applications
can happily ignore. For the short term, better safe than sorry.)
This proof assumes that neither compiler nor CPU will allow a lock
acquisition and release to be reordered, as doing so can result in
deadlock. The proof is as follows:
1. A given CPU declares a quiescent state under the protection of
its leaf rcu_node's lock.
2. If there is more than one level of rcu_node hierarchy, the
last CPU to declare a quiescent state will also acquire the
->lock of the next rcu_node up in the hierarchy, but only
after releasing the lower level's lock. The acquisition of this
lock clearly cannot occur prior to the acquisition of the leaf
node's lock.
3. Step 2 repeats until we reach the root rcu_node structure.
Please note again that only one lock is held at a time through
this process. The acquisition of the root rcu_node's ->lock
must occur after the release of that of the leaf rcu_node.
4. At this point, we set the ->completed field in the rcu_state
structure in rcu_report_qs_rsp(). However, if the rcu_node
hierarchy contains only one rcu_node, then in theory the code
preceding the quiescent state could leak into the critical
section. We therefore precede the update of ->completed with a
memory barrier. All CPUs will therefore agree that any updates
preceding any report of a quiescent state will have happened
before the update of ->completed.
5. Regardless of whether a new grace period is needed, rcu_start_gp()
will propagate the new value of ->completed to all of the leaf
rcu_node structures, under the protection of each rcu_node's ->lock.
If a new grace period is needed immediately, this propagation
will occur in the same critical section that ->completed was
set in, but courtesy of the memory barrier in #4 above, is still
seen to follow any pre-quiescent-state activity.
6. When a given CPU invokes __rcu_process_gp_end(), it becomes
aware of the end of the old grace period and therefore makes
any RCU callbacks that were waiting on that grace period eligible
for invocation.
If this CPU is the same one that detected the end of the grace
period, and if there is but a single rcu_node in the hierarchy,
we will still be in the single critical section. In this case,
the memory barrier in step #4 guarantees that all callbacks will
be seen to execute after each CPU's quiescent state.
On the other hand, if this is a different CPU, it will acquire
the leaf rcu_node's ->lock, and will again be serialized after
each CPU's quiescent state for the old grace period.
On the strength of this proof, this commit therefore removes the memory
barriers from rcu_process_callbacks() and adds one to rcu_report_qs_rsp().
The effect is to reduce the number of memory barriers by one and to
reduce the frequency of execution from about once per scheduling tick
per CPU to once per grace period.
This was reverted do to hangs found during testing by Yinghai Lu and
Ingo Molnar. Frederic Weisbecker supplied Yinghai with tracing that
located the underlying problem, and Frederic also provided the fix.
The underlying problem was that the HARDIRQ_ENTER() macro from
lib/locking-selftest.c invoked irq_enter(), which in turn invokes
rcu_irq_enter(), but HARDIRQ_EXIT() invoked __irq_exit(), which
does not invoke rcu_irq_exit(). This situation resulted in calls
to rcu_irq_enter() that were not balanced by the required calls to
rcu_irq_exit(). Therefore, after these locking selftests completed,
RCU's dyntick-idle nesting count was a large number (for example,
72), which caused RCU to to conclude that the affected CPU was not in
dyntick-idle mode when in fact it was.
RCU would therefore incorrectly wait for this dyntick-idle CPU, resulting
in hangs.
In contrast, with Frederic's patch, which replaces the irq_enter()
in HARDIRQ_ENTER() with an __irq_enter(), these tests don't ever call
either rcu_irq_enter() or rcu_irq_exit(), which works because the CPU
running the test is already marked as not being in dyntick-idle mode.
This means that the rcu_irq_enter() and rcu_irq_exit() calls and RCU
then has no problem working out which CPUs are in dyntick-idle mode and
which are not.
The reason that the imbalance was not noticed before the barrier patch
was applied is that the old implementation of rcu_enter_nohz() ignored
the nesting depth. This could still result in delays, but much shorter
ones. Whenever there was a delay, RCU would IPI the CPU with the
unbalanced nesting level, which would eventually result in rcu_enter_nohz()
being called, which in turn would force RCU to see that the CPU was in
dyntick-idle mode.
The reason that very few people noticed the problem is that the mismatched
irq_enter() vs. __irq_exit() occured only when the kernel was built with
CONFIG_DEBUG_LOCKING_API_SELFTESTS.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This patchset introduces cleancache, an optional new feature exposed
by the VFS layer that potentially dramatically increases page cache
effectiveness for many workloads in many environments at a negligible
cost. It does this by providing an interface to transcendent memory,
which is memory/storage that is not otherwise visible to and/or directly
addressable by the kernel.
Instead of being discarded, hooks in the reclaim code "put" clean
pages to cleancache. Filesystems that "opt-in" may "get" pages
from cleancache that were previously put, but pages in cleancache are
"ephemeral", meaning they may disappear at any time. And the size
of cleancache is entirely dynamic and unknowable to the kernel.
Filesystems currently supported by this patchset include ext3, ext4,
btrfs, and ocfs2. Other filesystems (especially those built entirely
on VFS) should be easy to add, but should first be thoroughly tested to
ensure coherency.
Details and a FAQ are provided in Documentation/vm/cleancache.txt
This first patch of eight in this cleancache series only adds two
new documentation files.
[v8: minor documentation changes by author]
[v3: akpm@linux-foundation.org: document sysfs API]
[v3: hch@infradead.org: move detailed description to Documentation/vm]
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy@goop.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Rik Van Riel <riel@redhat.com>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Andreas Dilger <adilger@sun.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (89 commits)
bonding: documentation and code cleanup for resend_igmp
bonding: prevent deadlock on slave store with alb mode (v3)
net: hold rtnl again in dump callbacks
Add Fujitsu 1000base-SX PCI ID to tg3
bnx2x: protect sequence increment with mutex
sch_sfq: fix peek() implementation
isdn: netjet - blacklist Digium TDM400P
via-velocity: don't annotate MAC registers as packed
xen: netfront: hold RTNL when updating features.
sctp: fix memory leak of the ASCONF queue when free asoc
net: make dev_disable_lro use physical device if passed a vlan dev (v2)
net: move is_vlan_dev into public header file (v2)
bug.h: Fix build with CONFIG_PRINTK disabled.
wireless: fix fatal kernel-doc error + warning in mac80211.h
wireless: fix cfg80211.h new kernel-doc warnings
iwlagn: dbg_fixed_rate only used when CONFIG_MAC80211_DEBUGFS enabled
dst: catch uninitialized metrics
be2net: hash key for rss-config cmd not set
bridge: initialize fake_rtable metrics
net: fix __dst_destroy_metrics_generic()
...
Fix up trivial conflicts in drivers/staging/brcm80211/brcmfmac/wl_cfg80211.c
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (75 commits)
mmc: core: eMMC bus width may not work on all platforms
mmc: sdhci: Auto-CMD23 fixes.
mmc: sdhci: Auto-CMD23 support.
mmc: core: Block CMD23 support for UHS104/SDXC cards.
mmc: sdhci: Implement MMC_CAP_CMD23 for SDHCI.
mmc: core: Use CMD23 for multiblock transfers when we can.
mmc: quirks: Add/remove quirks conditional support.
mmc: Add new VUB300 USB-to-SD/SDIO/MMC driver
mmc: sdhci-pxa: Add quirks for DMA/ADMA to match h/w
mmc: core: duplicated trial with same freq in mmc_rescan_try_freq()
mmc: core: add support for eMMC Dual Data Rate
mmc: core: eMMC signal voltage does not use CMD11
mmc: sdhci-pxa: add platform code for UHS signaling
mmc: sdhci: add hooks for setting UHS in platform specific code
mmc: core: clear MMC_PM_KEEP_POWER flag on resume
mmc: dw_mmc: fixed wrong regulator_enable in suspend/resume
mmc: sdhi: allow powering down controller with no card inserted
mmc: tmio: runtime suspend the controller, where possible
mmc: sdhi: support up to 3 interrupt sources
mmc: sdhi: print physical base address and clock rate
...
* 'kconfig-for-40' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
xconfig: merge code path to conf_write()
kconfig: do not record timestamp in .config
gconfig: Hide unused left treeview when start up the interface
gconfig: enable rules hint for main treeviews
MAINTAINERS: Update KCONFIG entry
kconfig-language: add to hints
kconfig: Document the new "visible if" syntax
kconfig: quiet commands when V=0
kconfig: change update-po-config to reflect new layout of arch/um
kconfig: make update-po-config work in KBUILD_OUTPUT
kconfig: rearrange clean-files
kconfig: change gconf to modify hostprogs-y like nconf and mconf
kconfig: change qconf to modify hostprogs-y like nconf and mconf
kconfig: only build kxgettext when needed
nconfig: Silence unused return values from wattrset
kconfig: Do not record timestamp in auto.conf and autoconf.h
kconfig: get rid of unused flags
kconfig: allow multiple inclusion of the same file
kconfig: Avoid buffer underrun in choice input
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: New driver for the SMSC EMC6W201
hwmon: (abituguru) Depend on DMI
hwmon: (it87) Use request_muxed_region
hwmon: (sch5627) Trigger Vbat measurements
hwmon: (sch5627) Add sch5627_send_cmd function
i8k: Integrate with the hwmon subsystem
hwmon: (max6650) Properly support the MAX6650
hwmon: (max6650) Drop device detection
Move ACPI power meter driver to hwmon
hwmon: (f71882fg) Add support for F71808A
hwmon: (f71882fg) Split has_beep in fan_has_beep and temp_has_beep
hwmon: (asc7621) Drop duplicate dependency
hwmon: (jc42) Change detection class
hwmon: Add driver for AMD family 15h processor power information
hwmon: (k10temp) Add support for Fam15h (Bulldozer)
hwmon: Use helper functions to set and get driver data
i8k: Avoid lahf in 64-bit code
