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* oom, PM: make OOM detection in the freezer path racelessMichal Hocko2015-02-111-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 5695be142e20 ("OOM, PM: OOM killed task shouldn't escape PM suspend") has left a race window when OOM killer manages to note_oom_kill after freeze_processes checks the counter. The race window is quite small and really unlikely and partial solution deemed sufficient at the time of submission. Tejun wasn't happy about this partial solution though and insisted on a full solution. That requires the full OOM and freezer's task freezing exclusion, though. This is done by this patch which introduces oom_sem RW lock and turns oom_killer_disable() into a full OOM barrier. oom_killer_disabled check is moved from the allocation path to the OOM level and we take oom_sem for reading for both the check and the whole OOM invocation. oom_killer_disable() takes oom_sem for writing so it waits for all currently running OOM killer invocations. Then it disable all the further OOMs by setting oom_killer_disabled and checks for any oom victims. Victims are counted via mark_tsk_oom_victim resp. unmark_oom_victim. The last victim wakes up all waiters enqueued by oom_killer_disable(). Therefore this function acts as the full OOM barrier. The page fault path is covered now as well although it was assumed to be safe before. As per Tejun, "We used to have freezing points deep in file system code which may be reacheable from page fault." so it would be better and more robust to not rely on freezing points here. Same applies to the memcg OOM killer. out_of_memory tells the caller whether the OOM was allowed to trigger and the callers are supposed to handle the situation. The page allocation path simply fails the allocation same as before. The page fault path will retry the fault (more on that later) and Sysrq OOM trigger will simply complain to the log. Normally there wouldn't be any unfrozen user tasks after try_to_freeze_tasks so the function will not block. But if there was an OOM killer racing with try_to_freeze_tasks and the OOM victim didn't finish yet then we have to wait for it. This should complete in a finite time, though, because - the victim cannot loop in the page fault handler (it would die on the way out from the exception) - it cannot loop in the page allocator because all the further allocation would fail and __GFP_NOFAIL allocations are not acceptable at this stage - it shouldn't be blocked on any locks held by frozen tasks (try_to_freeze expects lockless context) and kernel threads and work queues are not frozen yet Signed-off-by: Michal Hocko <mhocko@suse.cz> Suggested-by: Tejun Heo <tj@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysrq: convert printk to pr_* equivalentMichal Hocko2015-02-111-9/+9
| | | | | | | | | | | | | | | While touching this area let's convert printk to pr_*. This also makes the printing of continuation lines done properly. Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Tejun Heo <tj@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, oom: ensure memoryless node zonelist always includes zonesDavid Rientjes2014-08-061-1/+1
| | | | | | | | | | | | | | | | | | | | With memoryless node support being worked on, it's possible that for optimizations that a node may not have a non-NULL zonelist. When CONFIG_NUMA is enabled and node 0 is memoryless, this means the zonelist for first_online_node may become NULL. The oom killer requires a zonelist that includes all memory zones for the sysrq trigger and pagefault out of memory handler. Ensure that a non-NULL zonelist is always passed to the oom killer. [akpm@linux-foundation.org: fix non-numa build] Signed-off-by: David Rientjes <rientjes@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysrq,rcu: suppress RCU stall warnings while sysrq runsRik van Riel2014-06-061-0/+3
| | | | | | | | | | | | | | | | | | Some sysrq handlers can run for a long time, because they dump a lot of data onto a serial console. Having RCU stall warnings pop up in the middle of them only makes the problem worse. This patch temporarily disables RCU stall warnings while a sysrq request is handled. Signed-off-by: Rik van Riel <riel@redhat.com> Suggested-by: Paul McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Madper Xie <cxie@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysrq: rcu-ify __handle_sysrqRik van Riel2014-06-061-6/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Echoing values into /proc/sysrq-trigger seems to be a popular way to get information out of the kernel. However, dumping information about thousands of processes, or hundreds of CPUs to serial console can result in IRQs being blocked for minutes, resulting in various kinds of cascade failures. The most common failure is due to interrupts being blocked for a very long time. This can lead to things like failed IO requests, and other things the system cannot easily recover from. This problem is easily fixable by making __handle_sysrq use RCU instead of spin_lock_irqsave. This leaves the warning that RCU grace periods have not elapsed for a long time, but the system will come back from that automatically. It also leaves sysrq-from-irq-context when the sysrq keys are pressed, but that is probably desired since people want that to work in situations where the system is already hosed. The callers of register_sysrq_key and unregister_sysrq_key appear to be capable of sleeping. Signed-off-by: Rik van Riel <riel@redhat.com> Reported-by: Madper Xie <cxie@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Richard Weinberger <richard@nod.at> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/printk: use symbolic defines for console loglevelsBorislav Petkov2014-06-041-4/+4
| | | | | | | | | | | | | | | | | | | | ... instead of naked numbers. Stuff in sysrq.c used to set it to 8 which is supposed to mean above default level so set it to DEBUG instead as we're terminating/killing all tasks and we want to be verbose there. Also, correct the check in x86_64_start_kernel which should be >= as we're clearly issuing the string there for all debug levels, not only the magical 10. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Cc: Joe Perches <joe@perches.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sysrq: Allow magic SysRq key functions to be disabled through KconfigBen Hutchings2013-10-161-1/+1
| | | | | | | | | | Turn the initial value of sysctl kernel.sysrq (SYSRQ_DEFAULT_ENABLE) into a Kconfig variable. Original version by Bastian Blank <waldi@debian.org>. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-09-071-0/+42
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: "A new driver for slidebar on Ideapad laptops and a bunch of assorted driver fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (32 commits) Input: add SYN_MAX and SYN_CNT constants Input: max11801_ts - convert to devm Input: egalax-ts - fix typo and improve text Input: MAINTAINERS - change maintainer for cyttsp driver Input: cyttsp4 - kill 'defined but not used' compiler warnings Input: add driver for slidebar on Lenovo IdeaPad laptops Input: omap-keypad - set up irq type from DT Input: omap-keypad - enable wakeup capability for keypad. Input: omap-keypad - clear interrupts on open Input: omap-keypad - convert to threaded IRQ Input: omap-keypad - use bitfiled instead of hardcoded values Input: cyttsp4 - remove useless NULL test from cyttsp4_watchdog_timer() Input: wacom - fix error return code in wacom_probe() Input: as5011 - fix error return code in as5011_probe() Input: keyboard, serio - simplify use of devm_ioremap_resource Input: tegra-kbc - simplify use of devm_ioremap_resource Input: htcpen - fix incorrect placement of __initdata Input: qt1070 - add power management ops Input: wistron_btns - add MODULE_DEVICE_TABLE Input: wistron_btns - mark the Medion MD96500 keymap as tested ...
| * Input: sysrq - DT binding for key sequenceMathieu J. Poirier2013-08-121-0/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | Adding a simple device tree binding for the specification of key sequences. Definition of the keys found in the sequence are located in 'include/uapi/linux/input.h'. For the sysrq driver, holding the sequence of keys down for a specific amount of time will reset the system. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-07-041-4/+15
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: "First round of updates for the input subsystem. You will get a new touchsreen driver for Cypress 4th generation devices, a driver for a special controller implementing PS/2 protocol in OLPC devices, and a driver for power key for SiRFprimaII PWRC. HID and bcm5497 now support for the 2013 MacBook Air. EVIOCGKEY and the rest of evdev ioctls now flush events of matching type from the client's event queue so that clients can be sure any events received after issuing EVIOCG* ioctl are new events. And a host of cleanups and improvements in other drivers" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (87 commits) Input: cyttsp4 - kfree xfer_buf on error path in probe() Input: tps6507x-ts - select INPUT_POLLDEV Input: bcm5974 - add support for the 2013 MacBook Air HID: apple: Add support for the 2013 Macbook Air Input: cyttsp4 - leak on error path in probe() Input: cyttsp4 - silence NULL dereference warning Input: cyttsp4 - silence shift wrap warning Input: tps6507x-ts - convert to polled input device infrastructure ARM: davinci: da850-evm: remove vref from touchscreen platform data Input: cyttsp4 - SPI driver for Cypress TMA4XX touchscreen devices Input: cyttsp4 - I2C driver for Cypress TMA4XX touchscreen devices Input: cyttsp4 - add core driver for Cypress TMA4XX touchscreen devices Input: cyttsp - I2C driver split into two modules Input: add OLPC AP-SP driver Input: nspire-keypad - remove redundant dev_err call in nspire_keypad_probe() Input: tps6507x-ts - remove vref from platform data Input: tps6507x-ts - use bool for booleans Input: tps6507x-ts - remove bogus unreachable code Input: samsung-keypad - let device core setup the default pin configuration Input: wacom_i2c - implement hovering capability ...
| * Merge branch 'for-next' of git://github.com/rydberg/linux into nextDmitry Torokhov2013-06-271-19/+19
| |\ | | | | | | | | | Pull in changes from Henrik: "a trivial MT documentation fix".
| * | Input: sysrq - request graceful shutdown for key resetMathieu J. Poirier2013-06-061-4/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Attempt to reboot the system gracefully when a key combo is detected. If the reste combination is pressed the 2nd time we assume that graceful reboot failed and perform emergency reboot. This fucntionality is useful when UI is stuck but the system is otherwise working fine. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
* | | tty: replace strict_strtoul() with kstrtoul()Jingoo Han2013-06-031-1/+1
| |/ |/| | | | | | | | | | | | | | | The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-05-011-13/+40
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: "Assorted fixes and cleanups to the existing drivers plus a new driver for IMS Passenger Control Unit device they use for ther in-flight entertainment system." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (44 commits) Input: trackpoint - Optimize trackpoint init to use power-on reset Input: apbps2 - convert to devm_ioremap_resource() Input: ALPS - use %ph to print buffers ARM - shmobile: Armadillo800EVA: Move st1232 reset pin handling Input: st1232 - add reset pin handling Input: st1232 - convert to devm_* infrastructure Input: MT - handle semi-mt devices in core Input: adxl34x - use spi_get_drvdata() Input: ad7877 - use spi_get_drvdata() and spi_set_drvdata() Input: ads7846 - use spi_get_drvdata() and spi_set_drvdata() Input: ims-pcu - fix a memory leak on error Input: sysrq - supplement reset sequence with timeout functionality Input: tegra-kbc - support for defining row/columns based on SoC Input: imx_keypad - switch to using managed resources Input: arc_ps2 - add support for device tree Input: mma8450 - fix signed 12bits to 32bits conversion Input: eeti_ts - remove redundant null check Input: edt-ft5x06 - remove redundant null check before kfree Input: ad714x - add CONFIG_PM_SLEEP to suspend/resume functions Input: adxl34x - add CONFIG_PM_SLEEP to suspend/resume functions ...
| * Input: sysrq - supplement reset sequence with timeout functionalityMathieu J. Poirier2013-04-011-13/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Some devices have too few buttons, which it makes it hard to have a reset combo that won't trigger automatically. As such a timeout functionality that requires the combination to be held for a given amount of time before triggering is introduced. If a key combo is recognized and held for a 'timeout' amount of time, the system triggers a reset. If the timeout value is omitted the driver simply ignores the functionality. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
* | sysrq: fix inconstistent help message of sysrq keyzhangwei(Jovi)2013-03-151-19/+19
|/ | | | | | | | | | | | | | | | | | | | | | | Currently help message of /proc/sysrq-trigger highlight its upper-case characters, like below: SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E) memory-full-oom-kill(F) kill-all-tasks(I) ... this would confuse user trigger sysrq by upper-case character, which is inconsistent with the real lower-case character registed key. This inconsistent help message will also lead more confused when 26 upper-case letters put into use in future. This patch fix it. Thanks the comments from Andrew and Randy. Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Andrew Morton <akpm@linux-foundation.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysrq: don't depend on weak undefined arrays to have an address that ↵Linus Torvalds2013-02-271-8/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | compares as NULL When taking an address of an extern array, gcc quite naturally should be able to say "an address of an object can never be NULL" and just optimize away the test entirely. However, the new alternate sysrq reset code (commit 154b7a489a5b: "Input: sysrq - allow specifying alternate reset sequence") did exactly that, and declared platform_sysrq_reset_seq[] as a weak array, and expecting that testing the address of the array would show whether it actually got linked against something or not. And that doesn't work with all gcc versions. Clearly it works with *some* versions of gcc, and maybe it's even supposed to work, but it really is a very fragile concept. So instead of testing the address of the weak variable, just create a weak instance of that array that is empty. If some platform then has a real platform_sysrq_reset_seq[] that overrides our weak one, the linker will switch to that one, and it all works without any run-time conditionals at all. Reported-by: Dave Airlie <airlied@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-02-201-74/+202
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: "Two new touchpad drivers - Cypress APA I2C Trackpad and Cypress PS/2 touchpad and a big update to ALPS driver from Kevin Cernekee that adds support for "Rushmore" touchpads and paves way for adding support for "Dolphin" touchpads. There is also a new input driver for Goldfish emulator and also Android keyreset driver was folded into SysRq code. A few more drivers were updated with device tree bindings and others got some small cleanups and fixes." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (55 commits) Input: cyttsp-spi - remove duplicate MODULE_ALIAS() Input: tsc2005 - add MODULE_ALIAS Input: tegra-kbc - require CONFIG_OF, remove platform data Input: synaptics - initialize pointer emulation usage Input: MT - do not apply filtering on emulated events Input: bma150 - make some defines public and fix some comments Input: bma150 - fix checking pm_runtime_get_sync() return value Input: ALPS - enable trackstick on Rushmore touchpads Input: ALPS - add support for "Rushmore" touchpads Input: ALPS - make the V3 packet field decoder "pluggable" Input: ALPS - move pixel and bitmap info into alps_data struct Input: ALPS - fix command mode check Input: ALPS - rework detection of Pinnacle AGx touchpads Input: ALPS - move {addr,nibble}_command settings into alps_set_defaults() Input: ALPS - use function pointers for different protocol handlers Input: ALPS - rework detection sequence Input: ALPS - introduce helper function for repeated commands Input: ALPS - move alps_get_model() down below hw_init code Input: ALPS - copy "model" info into alps_data struct Input: ALPS - document the alps.h data structures ...
| * Input: sysrq - allow specifying alternate reset sequenceMathieu Poirier2013-01-171-74/+202
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds keyreset functionality to the sysrq driver. It allows certain button/key combinations to be used in order to trigger emergency reboots. Redefining the '__weak platform_sysrq_reset_seq' variable is required to trigger the feature. Alternatively keys can be passed to the driver via a module parameter. This functionality comes from the keyreset driver submitted by Arve Hjønnevåg in the Android kernel. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
* | sched/rt: Move rt specific bits into new header fileClark Williams2013-02-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | Move rt scheduler definitions out of include/linux/sched.h into new file include/linux/sched/rt.h Signed-off-by: Clark Williams <williams@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20130207094707.7b9f825f@riff.lan Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | mm, oom: ensure sysrq+f always passes valid zonelistDavid Rientjes2012-11-151-1/+2
|/ | | | | | | | | | With hotpluggable and memoryless nodes, it's possible that node 0 will not be online, so use the first online node's zonelist rather than hardcoding node 0 to pass a zonelist with all zones to the oom killer. Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sparc64: Add global PMU register dumping via sysrq.David S. Miller2012-10-161-0/+1
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* sysrq: use SEND_SIG_FORCED instead of force_sig()Anton Vorontsov2012-04-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change send_sig_all() to use do_send_sig_info(SEND_SIG_FORCED) instead of force_sig(SIGKILL). With the recent changes we do not need force_ to kill the CLONE_NEWPID tasks. And this is more correct. force_sig() can race with the exiting thread, while do_send_sig_info(group => true) kill the whole process. Some more notes from Oleg Nesterov: > Just one note. This change makes no difference for sysrq_handle_kill(). > But it obviously changes the behaviour sysrq_handle_term(). I think > this is fine, if you want to really kill the task which blocks/ignores > SIGTERM you can use sysrq_handle_kill(). > > Even ignoring the reasons why force_sig() is simply wrong here, > force_sig(SIGTERM) looks strange. The task won't be killed if it has > a handler, but SIG_IGN can't help. However if it has the handler > but blocks SIGTERM temporary (this is very common) it will be killed. Also, > force_sig() can't kill the process if the main thread has already > exited. IOW, it is trivial to create the process which can't be > killed by sysrq. So, this patch fixes the issue. Suggested-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Cc: Alan Cox <alan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, oom: force oom kill on sysrq+fDavid Rientjes2012-03-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | The oom killer chooses not to kill a thread if: - an eligible thread has already been oom killed and has yet to exit, and - an eligible thread is exiting but has yet to free all its memory and is not the thread attempting to currently allocate memory. SysRq+F manually invokes the global oom killer to kill a memory-hogging task. This is normally done as a last resort to free memory when no progress is being made or to test the oom killer itself. For both uses, we always want to kill a thread and never defer. This patch causes SysRq+F to always kill an eligible thread and can be used to force a kill even if another oom killed thread has failed to exit. Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Pekka Enberg <penberg@kernel.org> 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>
* vt:tackle kbd_tableAlan Cox2012-03-081-4/+2
| | | | | | | | | | | | | | | | | | | | | Keyboard struct lifetime is easy, but the locking is not and is completely ignored by the existing code. Tackle this one head on - Make the kbd_table private so we can run down all direct users - Hoick the relevant ioctl handlers into the keyboard layer - Lock them with the keyboard lock so they don't change mid keypress - Add helpers for things like console stop/start so we isolate the poking around properly - Tweak the braille console so it still builds There are a couple of FIXME locking cases left for ioctls that are so hideous they should be addressed in a later patch. After this patch the kbd_table is private and all the keyboard jiggery pokery is in one place. This update fixes speakup and also a memory leak in the original. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysrq: Properly check for kernel threadsAnton Vorontsov2012-02-091-3/+6
| | | | | | | | | | | | | There's a real possibility of killing kernel threads that might have issued use_mm(), so kthread's mm might become non-NULL. This patch fixes the issue by checking for PF_KTHREAD (just as get_task_mm()). Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysrq: Fix possible race with exiting taskAnton Vorontsov2012-02-091-0/+2
| | | | | | | | | | sysrq should grab the tasklist lock, otherwise calling force_sig() is not safe, as it might race with exiting task, which ->sighand might be set to NULL already. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs: move code out of buffer.cAl Viro2012-01-031-1/+1
| | | | | | | | | | | | | | | Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export kill_bdev as well, so brd doesn't have to open code it. Reduce buffer_head.h requirement accordingly. Removed a rather large comment from invalidate_bdev, as it looked a bit obsolete to bother moving. The small comment replacing it says enough. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* lib, arch: add filter argument to show_mem and fix private implementationsDavid Rientjes2011-03-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | Commit ddd588b5dd55 ("oom: suppress nodes that are not allowed from meminfo on oom kill") moved lib/show_mem.o out of lib/lib.a, which resulted in build warnings on all architectures that implement their own versions of show_mem(): lib/lib.a(show_mem.o): In function `show_mem': show_mem.c:(.text+0x1f4): multiple definition of `show_mem' arch/sparc/mm/built-in.o:(.text+0xd70): first defined here The fix is to remove __show_mem() and add its argument to show_mem() in all implementations to prevent this breakage. Architectures that implement their own show_mem() actually don't do anything with the argument yet, but they could be made to filter nodes that aren't allowed in the current context in the future just like the generic implementation. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: James Bottomley <James.Bottomley@hansenpartnership.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-02-151-1/+16
| | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: matrix_keypad - increase the limit of rows and columns Input: wacom - fix error path in wacom_probe() Input: ads7846 - check proper condition when freeing gpio Revert "Input: do not pass injected events back to the originating handler" Input: sysrq - rework re-inject logic Input: serio - clear pending rescans after sysfs driver rebind Input: rotary_encoder - use proper irqflags Input: wacom_w8001 - report resolution to userland
* Merge branch 'for-linus' of ↵Linus Torvalds2011-01-261-1/+1
| | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: wacom - pass touch resolution to clients through input_absinfo Input: wacom - add 2 Bamboo Pen and touch models Input: sysrq - ensure sysrq_enabled and __sysrq_enabled are consistent Input: sparse-keymap - fix KEY_VSW handling in sparse_keymap_setup Input: tegra-kbc - add tegra keyboard driver Input: gpio_keys - switch to using request_any_context_irq Input: serio - allow registered drivers to get status flag Input: ct82710c - return proper error code for ct82c710_open Input: bu21013_ts - added regulator support Input: bu21013_ts - remove duplicate resolution parameters Input: tnetv107x-ts - don't treat NULL clk as an error Input: tnetv107x-keypad - don't treat NULL clk as an error Fix up trivial conflicts in drivers/input/keyboard/Makefile due to additions of tc3589x/Tegra drivers
* Merge branch 'for-linus' of ↵Linus Torvalds2010-11-191-45/+124
| | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: fix typo in keycode validation supporting large scancodes Input: aiptek - tighten up permissions on sysfs attributes Input: sysrq - pass along lone Alt + SysRq
* TTY: create drivers/tty and move the tty core files thereGreg Kroah-Hartman2010-11-051-0/+811
The tty code should be in its own subdirectory and not in the char driver with all of the cruft that is currently there. Based on work done by Arnd Bergmann <arnd@arndb.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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