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2011-07-15Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: nilfs2: remove resize from unsupported features list
2011-07-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (21 commits) slip: fix wrong SLIP6 ifdef-endif placing natsemi: fix another dma-debug report sctp: ABORT if receive, reassmbly, or reodering queue is not empty while closing socket net: Fix default in docs for tcp_orphan_retries. hso: fix a use after free condition net/natsemi: Fix module parameter permissions XFRM: Fix memory leak in xfrm_state_update sctp: Enforce retransmission limit during shutdown mac80211: fix TKIP replay vulnerability mac80211: fix ie memory allocation for scheduled scans ssb: fix init regression of hostmode PCI core rtlwifi: rtl8192cu: Add new USB ID for Netgear WNA1000M ath9k: Fix tx throughput drops for AR9003 chips with AES encryption carl9170: add NEC WL300NU-AG usbid cfg80211: fix deadlock with rfkill/sched_scan by adding new mutex ath5k: fix incorrect use of drvdata in PCI suspend/resume code ath5k: fix incorrect use of drvdata in sysfs code Bluetooth: Fix memory leak under page timeouts Bluetooth: Fix regression with incoming L2CAP connections Bluetooth: Fix hidp disconnect deadlocks and lost wakeup ...
2011-07-13nilfs2: remove resize from unsupported features listRyusuke Konishi
Resize feature was supported by the commit 4e33f9eab07e but it was not reflected to the list of unsupported features in nilfs2.txt file. This updates the list to fix discrepancy. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
2011-07-11Documentation/Changes: remove some really obsolete textLinus Torvalds
That file harkens back to the days of the big 2.4 -> 2.6 version jump, and was based even then on older versions. Some of it is just obsolete, and Jesper Juhl points out that it talks about kernel versions 2.6 and should be updated to 3.0. Remove some obsolete text, and re-phrase some other to not be 2.6-specific. Reported-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-11Merge branch 'v4l_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: [media] msp3400: fill in v4l2_tuner based on vt->type field [media] tuner-core.c: don't change type field in g_tuner or g_frequency [media] cx18/ivtv: fix g_tuner support [media] tuner-core: power up tuner when called with s_power(1) [media] v4l2-ioctl.c: check for valid tuner type in S_HW_FREQ_SEEK [media] tuner-core: simplify the standard fixup [media] tuner-core/v4l2-subdev: document that the type field has to be filled in [media] v4l2-subdev.h: remove unused s_mode tuner op [media] feature-removal-schedule: change in how radio device nodes are handled [media] bttv: fix s_tuner for radio [media] pvrusb2: fix g/s_tuner support [media] v4l2-ioctl.c: prefill tuner type for g_frequency and g/s_tuner [media] tuner-core: fix tuner_resume: use t->mode instead of t->type [media] tuner-core: fix s_std and s_tuner
2011-07-11Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86: hp-wmi: fix use after free dell-laptop - using buffer without mutex_lock Revert: "dell-laptop: Toggle the unsupported hardware killswitch" platform-drivers-x86: set backlight type to BACKLIGHT_PLATFORM thinkpad-acpi: handle HKEY 0x4010, 0x4011 events drivers/platform/x86: Fix memory leak thinkpad-acpi: handle some new HKEY 0x60xx events acer-wmi: fix bitwise bug when set device state acer-wmi: Only update rfkill status for associated hotkey events
2011-07-11Documentation/spinlocks.txt: Remove reference to sti()/cli()Muthu Kumar
Since we removed sti()/cli() and related, how about removing it from Documentation/spinlocks.txt? Signed-off-by: Muthukumar R <muthur@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: PCI: conditional resource-reallocation through kernel parameter pci=realloc
2011-07-08PCI: conditional resource-reallocation through kernel parameter pci=reallocRam Pai
Multiple attempts to dynamically reallocate pci resources have unfortunately lead to regressions. Though we continue to fix the regressions and fine tune the dynamic-reallocation behavior, we have not reached a acceptable state yet. This patch provides a interim solution. It disables dynamic reallocation by default, but adds the ability to enable it through pci=realloc kernel command line parameter. Tested-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-07-08net: Fix default in docs for tcp_orphan_retries.David S. Miller
Default should be listed at 8 instead of 7. Reported-by: Denys Fedoryshchenko <denys@visp.net.lb> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-07FS-Cache: Add a helper to bulk uncache pages on an inodeDavid Howells
Add an FS-Cache helper to bulk uncache pages on an inode. This will only work for the circumstance where the pages in the cache correspond 1:1 with the pages attached to an inode's page cache. This is required for CIFS and NFS: When disabling inode cookie, we were returning the cookie and setting cifsi->fscache to NULL but failed to invalidate any previously mapped pages. This resulted in "Bad page state" errors and manifested in other kind of errors when running fsstress. Fix it by uncaching mapped pages when we disable the inode cookie. This patch should fix the following oops and "Bad page state" errors seen during fsstress testing. ------------[ cut here ]------------ kernel BUG at fs/cachefiles/namei.c:201! invalid opcode: 0000 [#1] SMP Pid: 5, comm: kworker/u:0 Not tainted 2.6.38.7-30.fc15.x86_64 #1 Bochs Bochs RIP: 0010: cachefiles_walk_to_object+0x436/0x745 [cachefiles] RSP: 0018:ffff88002ce6dd00 EFLAGS: 00010282 RAX: ffff88002ef165f0 RBX: ffff88001811f500 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000100 RDI: 0000000000000282 RBP: ffff88002ce6dda0 R08: 0000000000000100 R09: ffffffff81b3a300 R10: 0000ffff00066c0a R11: 0000000000000003 R12: ffff88002ae54840 R13: ffff88002ae54840 R14: ffff880029c29c00 R15: ffff88001811f4b0 FS: 00007f394dd32720(0000) GS:ffff88002ef00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007fffcb62ddf8 CR3: 000000001825f000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kworker/u:0 (pid: 5, threadinfo ffff88002ce6c000, task ffff88002ce55cc0) Stack: 0000000000000246 ffff88002ce55cc0 ffff88002ce6dd58 ffff88001815dc00 ffff8800185246c0 ffff88001811f618 ffff880029c29d18 ffff88001811f380 ffff88002ce6dd50 ffffffff814757e4 ffff88002ce6dda0 ffffffff8106ac56 Call Trace: cachefiles_lookup_object+0x78/0xd4 [cachefiles] fscache_lookup_object+0x131/0x16d [fscache] fscache_object_work_func+0x1bc/0x669 [fscache] process_one_work+0x186/0x298 worker_thread+0xda/0x15d kthread+0x84/0x8c kernel_thread_helper+0x4/0x10 RIP cachefiles_walk_to_object+0x436/0x745 [cachefiles] ---[ end trace 1d481c9af1804caa ]--- I tested the uncaching by the following means: (1) Create a big file on my NFS server (104857600 bytes). (2) Read the file into the cache with md5sum on the NFS client. Look in /proc/fs/fscache/stats: Pages : mrk=25601 unc=0 (3) Open the file for read/write ("bash 5<>/warthog/bigfile"). Look in proc again: Pages : mrk=25601 unc=25601 Reported-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de> cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-07[media] feature-removal-schedule: change in how radio device nodes are handledHans Verkuil
Radio devices have weird side-effects when used with combined TV/radio tuners and the V4L2 spec is ambiguous on how it should work. This results in inconsistent driver behavior which makes life hard for everyone. Be more strict in when and how the switch between radio and tv mode takes place and make sure all drivers behave the same. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-07thinkpad-acpi: handle HKEY 0x4010, 0x4011 eventsHenrique de Moraes Holschuh
Handle events 0x4010 and 0x4011 so that we do not pester users about them. These events report when the thinkpad is docked/undocked to a native hotplug dock (i.e. one that does not need ACPI handling, nor is represented in the ACPI device tree). Such docks are based on USB 2.0/3.0, and also work as port replicators. We really want a proper dock class to report these, or at least new input EV_SW events. Since it is not clear which one to use yet, keep reporting them as vendor-specific ThinkPad events. WARNING: As defined by the thinkpad-acpi sysfs ABI rules of engagement, the vendor-specific events will be REMOVED as soon as generic events are made available (duplicate events are a big problem), with an appropriate update to the thinkpad-acpi sysfs/event ABI versioning. Userspace is already prepared to provide easy backwards compatibility for such changes when convenient to the distro (see acpi-fakekey). * Event 0x4010: docking to hotplug dock/port replicator * Event 0x4011: undocking from hotplug dock/port replicator Typical usecase would be to trigger display reconfiguration. Reports mention T410, T510, and series 3 docks/port replicators. Special thanks to Robert de Rooy for his extensive report and analysis of the situation. http://www.thinkwiki.org/wiki/ThinkPad_Port_Replicator_Series_3 http://www.thinkwiki.org/wiki/ThinkPad_Mini_Dock_Series_3 http://www.thinkwiki.org/wiki/ThinkPad_Mini_Dock_Plus_Series_3 http://www.thinkwiki.org/wiki/ThinkPad_Mini_Dock_Plus_Series_3_for_Mobile_Workstations http://lenovoblogs.com/insidethebox/?p=290 Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Reported-by: Claudius Hubig <claudiushubig@chubig.net> Reported-by: Doctor Bill <docbill@gmail.com> Reported-by: Korte Noack <gbk.noack@gmx.de> Reported-by: Robert de Rooy <robert.de.rooy@gmail.com> Reported-by: Sebastian Will <swill@csail.mit.edu> Signed-off-by: Matthew Garrett <mjg@redhat.com>
2011-07-07thinkpad-acpi: handle some new HKEY 0x60xx eventsHenrique de Moraes Holschuh
Handle some user interface events from the newer Lenovo models. We are likely to do something smart with these events in the future, for now, hide the ones we are already certain about from the user and userspace both. * Events 0x6000 and 0x6005 are key-related. 0x6005 is not properly identified yet. Ignore these events, and do not report them. * Event 0x6040 has not been properly identified yet, and we don't know if it is important (looks like it isn't, but still...). Keep reporting it. * Change the message the driver outputs on unknown 0x6xxx events, as all recent events are not related to thermal alarms. Degrade log level from ALERT to WARNING. Thanks to all users who reported these events or asked about them in a number of mailing lists. Your help is highly appreciated, even if I did took a lot of time to act on them. For that I apologise. I will list those that identified the reasons for the events as "reported-by", and I apologise in advance if I leave anyone out: it was not done on purpose, I made the mistake of not properly tagging all event report emails separately, and might have missed some. Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Reported-by: Markus Malkusch <markus@malkusch.de> Reported-by: Peter Giles <g1l3sp@gmail.com> Signed-off-by: Matthew Garrett <mjg@redhat.com>
2011-07-06Documentation: fix cgroup blkio throttle filenamesAndrea Righi
All the blkio.throttle.* file names are incorrectly reported without ".throttle" in the documentation. Fix it. Signed-off-by: Andrea Righi <andrea@betterlinux.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-06Documentation: update CodingStyle memory allocatorsJesper Juhl
The list of available general purpose memory allocators in Documentation/CodingStyle chapter 14 is incomplete. This patch adds the missing vzalloc() to the list. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-03Merge branch 'pm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PM / Runtime: Update documentation regarding driver removal PM: Documentation: fix typo: pm_runtime_idle_sync() doesn't exist.
2011-07-03Merge branch 'hwmon-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging * 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: hwmon: (k10temp) Update documentation for Fam12h hwmon-vid: Fix typo in VIA CPU name hwmon: (f71882fg) Add support for the F71869A hwmon: Use <> rather than () around my e-mail address hwmon: (emc6w201) Properly handle all errors
2011-07-03hwmon: (k10temp) Update documentation for Fam12hClemens Ladisch
Add some CPU series IDs and links to the Fam12h datasheets. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-07-03hwmon: (f71882fg) Add support for the F71869AHans de Goede
The F71869A is almost the same as the F71869F/E, except that it has the normal number of temp and pwm zones for a F71882FG derived chip, rather then the limited number of the F71869F/E. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Max Baldwin <archerseven@gmail.com> Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2011-07-02PM / Runtime: Update documentation regarding driver removalRafael J. Wysocki
Commit e1866b33b1e89f077b7132daae3dfd9a594e9a1a (PM / Runtime: Rework runtime PM handling during driver removal) forgot to update the documentation in Documentation/power/runtime_pm.txt to match the new code in drivers/base/dd.c. Update that documentation to match the code it describes. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Kevin Hilman <khilman@ti.com>
2011-07-02PM: Documentation: fix typo: pm_runtime_idle_sync() doesn't exist.Kevin Hilman
Replace reference to pm_runtime_idle_sync() in the driver core with pm_runtime_put_sync() which is used in the code. Signed-off-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-06-28Merge branch 'usb-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6 * 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: MAINTAINERS: add myself as maintainer of USB/IP usb: r8a66597-hcd: fix cannot detect low/full speed device USB: ehci-ath79: fix a NULL pointer dereference USB: Add new FT232H chip to drivers/usb/serial/ftdi_sio.c usb/isp1760: Fix bug preventing the unlinking of control urbs USB: Fix up URB error codes to reflect implementation. xhci: Always set urb->status to zero for isoc endpoints. xhci: Add reset on resume quirk for asrock p67 host xHCI 1.0: Incompatible Device Error USB: don't let errors prevent system sleep USB: don't let the hub driver prevent system sleep USB: change maintainership of ohci-hcd and ehci-hcd xHCI 1.0: Force Stopped Event(FSE) xhci: Don't warn about zeroed bMaxBurst descriptor field. USB: Free bandwidth when usb_disable_device is called. xhci: Reject double add of active endpoints. USB: TI 3410/5052 USB Serial Driver: Fix mem leak when firmware is too big. usb: musb: gadget: clear TXPKTRDY flag when set FLUSHFIFO usb: musb: host: compare status for negative error values
2011-06-21PM / Domains: Update documentationRafael J. Wysocki
Commit 4d27e9dcff00a6425d779b065ec8892e4f391661 (PM: Make power domain callbacks take precedence over subsystem ones) forgot to update the device power management documentation to take changes made by it into account. Correct that mistake. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-06-21PM: Update documentation regarding sysdevsRafael J. Wysocki
The part of Documentation/power/devices.txt regarding sysdevs is not valid any more after commit 2e711c04dbbf7a7732a3f7073b1fc285d12b369d (PM: Remove sysdev suspend, resume and shutdown operations), so remove it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-06-21PM / Runtime: Update doc: usage count no longer incremented across system PMKevin Hilman
Commit e8665002477f0278f84f898145b1f141ba26ee26 (PM: Allow pm_runtime_suspend() to succeed during system suspend) removed usage count increment across system PM. Update doc to reflect this. Signed-off-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-06-19Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: Move RCU_BOOST #ifdefs to header file rcu: use softirq instead of kthreads except when RCU_BOOST=y rcu: Use softirq to address performance regression rcu: Simplify curing of load woes
2011-06-17USB: Fix up URB error codes to reflect implementation.Sarah Sharp
Documentation/usb/error-codes.txt mentions that urb->status can be set to -EXDEV, if the isochronous transfer was not fully completed. However, in practice, EHCI, UHCI, and OHCI all only set -EXDEV in the individual frame status, never in the URB status. Those host controller actually always pass in a zero status to usb_hcd_giveback_urb, and rely on the core to set the appropriate status value. The xHCI driver ran into issues with the uvcvideo driver when it tried to set -EXDEV in urb->status, because the driver refused to submit URBs, and the userspace camera application's video froze. Clean up the documentation to reflect the actual implementation. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu>
2011-06-15Documentation: fix cgroup typos and formattingJörg Sommer
Fix format and spelling. Signed-off-by: Jörg Sommer <joerg@alea.gnuu.de> Acked-by: Paul Menage <menage@google.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15Documentation: update cgroupfs mount pointJörg Sommer
According to commit 676db4af0430 ("cgroupfs: create /sys/fs/cgroup to mount cgroupfs on") the canonical mountpoint for the cgroup filesystem is /sys/fs/cgroup. Hence, this should be used in the documentation. Signed-off-by: Jörg Sommer <joerg@alea.gnuu.de> Acked-by: Paul Menage <menage@google.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15Documentation: update kmemleak supported archsMaxin B. John
Instead of listing the architectures that are supported by kmemleak in Documentation/kmemleak.txt, just refer people to the list of supported architecutures in lib/Kconfig.debug so that Documentation/kmemleak.txt does not need more updates for this. Signed-off-by: Maxin B. John <maxin.john@gmail.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15Documentation: update printk-formats.txtAndrew Murray
This patch updates the incomplete documentation concerning the printk extended format specifiers. Signed-off-by: Andrew Murray <amurray@mpc-data.co.uk> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15Documentation/feature-removal-schedule.txt: remove ns_cgroup from ↵akpm@linux-foundation.org
feature-removal-schedule.txt Commit a77aea92010acf ("cgroup: remove the ns_cgroup") removed the ns_cgroup but it forgot to remove the related doc in feature-removal-schedule.txt. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Cc: Serge E. Hallyn <serge.hallyn@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15memcg: add documentation for the memory.numastat APIYing Han
[akpm@linux-foundation.org: rework text, fit it into 80-cols] Signed-off-by: Ying Han <yinghan@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-15backlight: new driver for the ADP8870 backlight devicesMichael Hennerich
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-14rcu: Use softirq to address performance regressionShaohua Li
Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread) introduced performance regression. In an AIM7 test, this commit degraded performance by about 40%. The commit runs rcu callbacks in a kthread instead of softirq. We observed high rate of context switch which is caused by this. Out test system has 64 CPUs and HZ is 1000, so we saw more than 64k context switch per second which is caused by RCU's per-CPU kthread. A trace showed that most of the time the RCU per-CPU kthread doesn't actually handle any callbacks, but instead just does a very small amount of work handling grace periods. This means that RCU's per-CPU kthreads are making the scheduler do quite a bit of work in order to allow a very small amount of RCU-related processing to be done. Alex Shi's analysis determined that this slowdown is due to lock contention within the scheduler. Unfortunately, as Peter Zijlstra points out, the scheduler's real-time semantics require global action, which means that this contention is inherent in real-time scheduling. (Yes, perhaps someone will come up with a workaround -- otherwise, -rt is not going to do well on large SMP systems -- but this patch will work around this issue in the meantime. And "the meantime" might well be forever.) This patch therefore re-introduces softirq processing to RCU, but only for core RCU work. RCU callbacks are still executed in kthread context, so that only a small amount of RCU work runs in softirq context in the common case. This should minimize ksoftirqd execution, allowing us to skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Tested-by: "Alex,Shi" <alex.shi@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-06-14Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds
* 'for-linus' of git://neil.brown.name/md: md/raid5: remove unusual use of bio_iovec_idx() md/raid5: fix FUA request handling in ops_run_io() md/raid5: fix raid5_set_bi_hw_segments md:Documentation/md.txt - fix typo md/bitmap: remove unused fields from struct bitmap md/bitmap: use proper accessor macro md: check ->hot_remove_disk when removing disk md: Using poll /proc/mdstat can monitor the events of adding a spare disks MD: use is_power_of_2 macro MD: raid5 do not set fullsync MD: support initial bitmap creation in-kernel MD: add sync_super to mddev_t struct MD: raid1 changes to allow use by device mapper MD: move thread wakeups into resume MD: possible typo MD: no sync IO while suspended MD: no integrity register if no gendisk
2011-06-09md:Documentation/md.txt - fix typoNeilBrown
Reported-by: CoolCold <coolthecold@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2011-06-07usb-storage: redo incorrect readsAlan Stern
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>
2011-06-02Merge git://git.infradead.org/iommu-2.6Linus Torvalds
* 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
2011-06-01intel-iommu: Enable super page (2MiB, 1GiB, etc.) supportYouquan Song
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>
2011-05-30lguest: remove support for VIRTIO_F_NOTIFY_ON_EMPTY.Rusty Russell
No virtio device does this any more, so no need to clutter lguest with it. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-05-30lguest: fix up compilation after moveRusty Russell
ed16648eb5b86917f0b90bdcdbc857202da72f90 "Move kvm, uml, and lguest subdirectories" broke the lguest example launcher. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-05-29Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86 * '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 ...
2011-05-29Merge branch 'x86-platform-next' into x86-platformMatthew Garrett
2011-05-29Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * '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
2011-05-29Merge branch 'idle-release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6 * '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
2011-05-29x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline paramLen Brown
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>
2011-05-29x86 idle: deprecate "no-hlt" cmdline paramLen Brown
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>
2011-05-29x86 idle APM: deprecate CONFIG_APM_CPU_IDLELen Brown
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>