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2013-07-03Merge branch 'for-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
Pull workqueue changes from Tejun Heo: "Surprisingly, Lai and I didn't break too many things implementing custom pools and stuff last time around and there aren't any follow-up changes necessary at this point. The only change in this pull request is Viresh's patches to make some per-cpu workqueues to behave as unbound workqueues dependent on a boot param whose default can be configured via a config option. This leads to higher processing overhead / lower bandwidth as more work items are bounced across CPUs; however, it can lead to noticeable powersave in certain configurations - ~10% w/ idlish constant workload on a big.LITTLE configuration according to Viresh. This is because per-cpu workqueues interfere with how the scheduler perceives whether or not each CPU is idle by forcing pinned tasks on them, which makes the scheduler's power-aware scheduling decisions less effective. Its effectiveness is likely less pronounced on homogenous configurations and this type of optimization can probably be made automatic; however, the changes are pretty minimal and the affected workqueues are clearly marked, so it's an easy gain for some configurations for the time being with pretty unintrusive changes." * 'for-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: fbcon: queue work on power efficient wq block: queue work on power efficient wq PHYLIB: queue work on system_power_efficient_wq workqueue: Add system wide power_efficient workqueues workqueues: Introduce new flag WQ_POWER_EFFICIENT for power oriented workqueues
2013-07-03module: cleanup call chain.Rusty Russell
Fold alloc_module_percpu into percpu_modalloc(). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-07-03module: do percpu allocation after uniqueness check. No, really!Rusty Russell
v3.8-rc1-5-g1fb9341 was supposed to stop parallel kvm loads exhausting percpu memory on large machines: Now we have a new state MODULE_STATE_UNFORMED, we can insert the module into the list (and thus guarantee its uniqueness) before we allocate the per-cpu region. In my defence, it didn't actually say the patch did this. Just that we "can". This patch actually *does* it. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Tested-by: Jim Hull <jim.hull@hp.com> Cc: stable@kernel.org # 3.8
2013-07-02Merge branch 'x86-ras-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS update from Ingo Molnar: "The changes in this tree are: - ACPI APEI (ACPI Platform Error Interface) improvements, by Chen Gong - misc MCE fixes/cleanups" * 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Update MCE severity condition check mce: acpi/apei: Add comments to clarify usage of the various bitfields in the MCA subsystem ACPI/APEI: Update einj documentation for param1/param2 ACPI/APEI: Add parameter check before error injection ACPI, APEI, EINJ: Fix error return code in einj_init() x86, mce: Fix "braodcast" typo
2013-07-02Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes: - load-calculation cleanups and improvements, by Alex Shi - various nohz related tidying up of statisics, by Frederic Weisbecker - factor out /proc functions to kernel/sched/proc.c, by Paul Gortmaker - simplify the RT policy scheduler, by Kirill Tkhai - various fixes and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) sched/debug: Remove CONFIG_FAIR_GROUP_SCHED mask sched/debug: Fix formatting of /proc/<PID>/sched sched: Fix typo in struct sched_avg member description sched/fair: Fix typo describing flags in enqueue_entity sched/debug: Add load-tracking statistics to task sched: Change get_rq_runnable_load() to static and inline sched/tg: Remove tg.load_weight sched/cfs_rq: Change atomic64_t removed_load to atomic_long_t sched/tg: Use 'unsigned long' for load variable in task group sched: Change cfs_rq load avg to unsigned long sched: Consider runnable load average in move_tasks() sched: Compute runnable load avg in cpu_load and cpu_avg_load_per_task sched: Update cpu load after task_tick sched: Fix sleep time double accounting in enqueue entity sched: Set an initial value of runnable avg for new forked task sched: Move a few runnable tg variables into CONFIG_SMP Revert "sched: Introduce temporary FAIR_GROUP_SCHED dependency for load-tracking" sched: Don't mix use of typedef ctl_table and struct ctl_table sched: Remove WARN_ON(!sd) from init_sched_groups_power() sched: Fix memory leakage in build_sched_groups() ...
2013-07-02Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Kernel improvements: - watchdog driver improvements by Li Zefan - Power7 CPI stack events related improvements by Sukadev Bhattiprolu - event multiplexing via hrtimers and other improvements by Stephane Eranian - kernel stack use optimization by Andrew Hunter - AMD IOMMU uncore PMU support by Suravee Suthikulpanit - NMI handling rate-limits by Dave Hansen - various hw_breakpoint fixes by Oleg Nesterov - hw_breakpoint overflow period sampling and related signal handling fixes by Jiri Olsa - Intel Haswell PMU support by Andi Kleen Tooling improvements: - Reset SIGTERM handler in workload child process, fix from David Ahern. - Makefile reorganization, prep work for Kconfig patches, from Jiri Olsa. - Add automated make test suite, from Jiri Olsa. - Add --percent-limit option to 'top' and 'report', from Namhyung Kim. - Sorting improvements, from Namhyung Kim. - Expand definition of sysfs format attribute, from Michael Ellerman. Tooling fixes: - 'perf tests' fixes from Jiri Olsa. - Make Power7 CPI stack events available in sysfs, from Sukadev Bhattiprolu. - Handle death by SIGTERM in 'perf record', fix from David Ahern. - Fix printing of perf_event_paranoid message, from David Ahern. - Handle realloc failures in 'perf kvm', from David Ahern. - Fix divide by 0 in variance, from David Ahern. - Save parent pid in thread struct, from David Ahern. - Handle JITed code in shared memory, from Andi Kleen. - Fixes for 'perf diff', from Jiri Olsa. - Remove some unused struct members, from Jiri Olsa. - Add missing liblk.a dependency for python/perf.so, fix from Jiri Olsa. - Respect CROSS_COMPILE in liblk.a, from Rabin Vincent. - No need to do locking when adding hists in perf report, only 'top' needs that, from Namhyung Kim. - Fix alignment of symbol column in in the hists browser (top, report) when -v is given, from NAmhyung Kim. - Fix 'perf top' -E option behavior, from Namhyung Kim. - Fix bug in isupper() and islower(), from Sukadev Bhattiprolu. - Fix compile errors in bp_signal 'perf test', from Sukadev Bhattiprolu. ... and more things" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (102 commits) perf/x86: Disable PEBS-LL in intel_pmu_pebs_disable() perf/x86: Fix shared register mutual exclusion enforcement perf/x86/intel: Support full width counting x86: Add NMI duration tracepoints perf: Drop sample rate when sampling is too slow x86: Warn when NMI handlers take large amounts of time hw_breakpoint: Introduce "struct bp_cpuinfo" hw_breakpoint: Simplify *register_wide_hw_breakpoint() hw_breakpoint: Introduce cpumask_of_bp() hw_breakpoint: Simplify the "weight" usage in toggle_bp_slot() paths hw_breakpoint: Simplify list/idx mess in toggle_bp_slot() paths perf/x86/intel: Add mem-loads/stores support for Haswell perf/x86/intel: Support Haswell/v4 LBR format perf/x86/intel: Move NMI clearing to end of PMI handler perf/x86/intel: Add Haswell PEBS support perf/x86/intel: Add simple Haswell PMU support perf/x86/intel: Add Haswell PEBS record support perf/x86/intel: Fix sparse warning perf/x86/amd: AMD IOMMU Performance Counter PERF uncore PMU implementation perf/x86/amd: Add IOMMU Performance Counter resource management ...
2013-07-02Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core irq changes from Ingo Molnar: "The main changes: - generic-irqchip driver additions, cleanups and fixes - 3 new irqchip drivers: ARMv7-M NVIC, TB10x and Marvell Orion SoCs - irq_get_trigger_type() simplification and cross-arch cleanup - various cleanups, simplifications - documentation updates" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits) softirq: Use _RET_IP_ genirq: Add the generic chip to the genirq docbook genirq: generic-chip: Export some irq_gc_ functions genirq: Fix can_request_irq() for IRQs without an action irqchip: exynos-combiner: Staticize combiner_init irqchip: Add support for ARMv7-M NVIC irqchip: Add TB10x interrupt controller driver irqdomain: Use irq_get_trigger_type() to get IRQ flags MIPS: octeon: Use irq_get_trigger_type() to get IRQ flags arm: orion: Use irq_get_trigger_type() to get IRQ flags mfd: stmpe: use irq_get_trigger_type() to get IRQ flags mfd: twl4030-irq: Use irq_get_trigger_type() to get IRQ flags gpio: mvebu: Use irq_get_trigger_type() to get IRQ flags genirq: Add irq_get_trigger_type() to get IRQ flags genirq: Irqchip: document gcflags arg of irq_alloc_domain_generic_chips genirq: Set irq thread to RT priority on creation irqchip: Add support for Marvell Orion SoCs genirq: Add kerneldoc for irq_disable. genirq: irqchip: Add mask to block out invalid irqs genirq: Generic chip: Add linear irq domain support ...
2013-07-02Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The major changes: - Simplify RCU's grace-period and callback processing based on the new numbering for callbacks. - Removal of TINY_PREEMPT_RCU in favor of TREE_PREEMPT_RCU for single-CPU low-latency systems. - SRCU-related changes and fixes. - Miscellaneous fixes, including converting a few remaining printk() calls to pr_*(). - Documentation updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) rcu: Shrink TINY_RCU by reworking CPU-stall ifdefs rcu: Shrink TINY_RCU by moving exit_rcu() rcu: Remove TINY_PREEMPT_RCU tracing documentation rcu: Consolidate rcutiny_plugin.h ifdefs rcu: Remove rcu_preempt_note_context_switch() rcu: Remove the CONFIG_TINY_RCU ifdefs in rcutiny.h rcu: Remove check_cpu_stall_preempt() rcu: Simplify RCU_TINY RCU callback invocation rcu: Remove rcu_preempt_process_callbacks() rcu: Remove rcu_preempt_remove_callbacks() rcu: Remove rcu_preempt_check_callbacks() rcu: Remove show_tiny_preempt_stats() rcu: Remove TINY_PREEMPT_RCU powerpc,kvm: fix imbalance srcu_read_[un]lock() rcu: Remove srcu_read_lock_raw() and srcu_read_unlock_raw(). rcu: Apply Dave Jones's NOCB Kconfig help feedback rcu: Merge adjacent identical ifdefs rcu: Drive quiescent-state-forcing delay from HZ rcu: Remove "Experimental" flags kthread: Add kworker kthreads to OS-jitter documentation ...
2013-07-02Merge branch 'core-mutexes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull WW mutex support from Ingo Molnar: "This tree adds support for wound/wait style locks, which the graphics guys would like to make use of in the TTM graphics subsystem. Wound/wait mutexes are used when other multiple lock acquisitions of a similar type can be done in an arbitrary order. The deadlock handling used here is called wait/wound in the RDBMS literature: The older tasks waits until it can acquire the contended lock. The younger tasks needs to back off and drop all the locks it is currently holding, ie the younger task is wounded. See this LWN.net description of W/W mutexes: https://lwn.net/Articles/548909/ The comments there outline specific usecases for this facility (which have already been implemented for the DRM tree). Also see Documentation/ww-mutex-design.txt for more details" * 'core-mutexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking-selftests: Handle unexpected failures more strictly mutex: Add more w/w tests to test EDEADLK path handling mutex: Add more tests to lib/locking-selftest.c mutex: Add w/w tests to lib/locking-selftest.c mutex: Add w/w mutex slowpath debugging mutex: Add support for wound/wait style locks arch: Make __mutex_fastpath_lock_retval return whether fastpath succeeded or not
2013-07-02Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking changes from Ingo Molnar: "Four miscellanous standalone fixes for futexes, rtmutexes and Kconfig.locks." * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Use freezable blocking call futex: Take hugepages into account when generating futex_key rtmutex: Document rt_mutex_adjust_prio_chain() locking: Fix copy/paste errors of "ARCH_INLINE_*_UNLOCK_BH"
2013-07-02Merge tag 'driver-core-3.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here's the big driver core merge for 3.11-rc1 Lots of little things, and larger firmware subsystem updates, all described in the shortlog. Nice thing here is that we finally get rid of CONFIG_HOTPLUG, after 10+ years, thanks to Stephen Rohtwell (it had been always on for a number of kernel releases, now it's just removed)" * tag 'driver-core-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (27 commits) driver core: device.h: fix doc compilation warnings firmware loader: fix another compile warning with PM_SLEEP unset build some drivers only when compile-testing firmware loader: fix compile warning with PM_SLEEP set kobject: sanitize argument for format string sysfs_notify is only possible on file attributes firmware loader: simplify holding module for request_firmware firmware loader: don't export cache_firmware and uncache_firmware drivers/base: Use attribute groups to create sysfs memory files firmware loader: fix compile warning firmware loader: fix build failure with !CONFIG_FW_LOADER_USER_HELPER Documentation: Updated broken link in HOWTO Finally eradicate CONFIG_HOTPLUG driver core: firmware loader: kill FW_ACTION_NOHOTPLUG requests before suspend driver core: firmware loader: don't cache FW_ACTION_NOHOTPLUG firmware Documentation: Tidy up some drivers/base/core.c kerneldoc content. platform_device: use a macro instead of platform_driver_register firmware: move EXPORT_SYMBOL annotations firmware: Avoid deadlock of usermodehelper lock at shutdown dell_rbu: Select CONFIG_FW_LOADER_USER_HELPER explicitly ...
2013-07-02Merge tag 'fscache-20130702' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull FS-Cache updates from David Howells: "This contains a number of fixes for various FS-Cache issues plus some cleanups. The commits are, in order: 1) Provide a system wait_on_atomic_t() and wake_up_atomic_t() sharing the bit-wait table (enhancement for #8). 2) Don't put spin_lock() in a while-condition as spin_lock() may have a do {} while(0) wrapper (cleanup). 3) Symbolically name i_mutex lock classes rather than using numbers in CacheFiles (cleanup). 4) Don't sleep in page release if __GFP_FS is not set (deadlock vs ext4). 5) Uninline fscache_object_init() (cleanup for #7). 6) Wrap checks on object state (cleanup for #7). 7) Simplify the object state machine by separating work states from wait states. 8) Simplify cookie retention by objects (NULL pointer deref fix). 9) Remove unused list_to_page() macro (cleanup). 10) Make the remaining-pages counter in the retrieval op atomic (assertion failure fix). 11) Don't use spin_is_locked() in assertions (assertion failure fix)" * tag 'fscache-20130702' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: FS-Cache: Don't use spin_is_locked() in assertions FS-Cache: The retrieval remaining-pages counter needs to be atomic_t cachefiles: remove unused macro list_to_page() FS-Cache: Simplify cookie retention for fscache_objects, fixing oops FS-Cache: Fix object state machine to have separate work and wait states FS-Cache: Wrap checks on object state FS-Cache: Uninline fscache_object_init() FS-Cache: Don't sleep in page release if __GFP_FS is not set CacheFiles: name i_mutex lock class explicitly fs/fscache: remove spin_lock() from the condition in while() Add wait_on_atomic_t() and wake_up_atomic_t()
2013-07-02tick: Sanitize broadcast control logicThomas Gleixner
The recent implementation of a generic dummy timer resulted in a different registration order of per cpu local timers which made the broadcast control logic go belly up. If the dummy timer is the first clock event device which is registered for a CPU, then it is installed, the broadcast timer is initialized and the CPU is marked as broadcast target. If a real clock event device is installed after that, we can fail to take the CPU out of the broadcast mask. In the worst case we end up with two periodic timer events firing for the same CPU. One from the per cpu hardware device and one from the broadcast. Now the problem is that we have no way to distinguish whether the system is in a state which makes broadcasting necessary or the broadcast bit was set due to the nonfunctional dummy timer installment. To solve this we need to keep track of the system state seperately and provide a more detailed decision logic whether we keep the CPU in broadcast mode or not. The old decision logic only clears the broadcast mode, if the newly installed clock event device is not affected by power states. The new logic clears the broadcast mode if one of the following is true: - The new device is not affected by power states. - The system is not in a power state affected mode - The system has switched to oneshot mode. The oneshot broadcast is controlled from the deep idle state. The CPU is not in idle at this point, so it's safe to remove it from the mask. If we clear the broadcast bit for the CPU when a new device is installed, we also shutdown the broadcast device when this was the last CPU in the broadcast mask. If the broadcast bit is kept, then we leave the new device in shutdown state and rely on the broadcast to deliver the timer interrupts via the broadcast ipis. Reported-and-tested-by: Stehle Vincent-B46079 <B46079@freescale.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org>, Cc: Mark Rutland <mark.rutland@arm.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-07-02tick: Prevent uncontrolled switch to oneshot modeThomas Gleixner
When the system switches from periodic to oneshot mode, the broadcast logic causes a possibility that a CPU which has not yet switched to oneshot mode puts its own clock event device into oneshot mode without updating the state and the timer handler. CPU0 CPU1 per cpu tickdev is in periodic mode and switched to broadcast Switch to oneshot mode tick_broadcast_switch_to_oneshot() cpumask_copy(tick_oneshot_broacast_mask, tick_broadcast_mask); broadcast device mode = oneshot Timer interrupt irq_enter() tick_check_oneshot_broadcast() dev->set_mode(ONESHOT); tick_handle_periodic() if (dev->mode == ONESHOT) dev->next_event += period; FAIL. We fail, because dev->next_event contains KTIME_MAX, if the device was in periodic mode before the uncontrolled switch to oneshot happened. We must copy the broadcast bits over to the oneshot mask, because otherwise a CPU which relies on the broadcast would not been woken up anymore after the broadcast device switched to oneshot mode. So we need to verify in tick_check_oneshot_broadcast() whether the CPU has already switched to oneshot mode. If not, leave the device untouched and let the CPU switch controlled into oneshot mode. This is a long standing bug, which was never noticed, because the main user of the broadcast x86 cannot run into that scenario, AFAICT. The nonarchitected timer mess of ARM creates a gazillion of differently broken abominations which trigger the shortcomings of that broadcast code, which better had never been necessary in the first place. Reported-and-tested-by: Stehle Vincent-B46079 <B46079@freescale.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org>, Cc: Mark Rutland <mark.rutland@arm.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307012153060.4013@ionos.tec.linutronix.de Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-07-02tick: Make oneshot broadcast robust vs. CPU offliningThomas Gleixner
In periodic mode we remove offline cpus from the broadcast propagation mask. In oneshot mode we fail to do so. This was not a problem so far, but the recent changes to the broadcast propagation introduced a constellation which can result in a NULL pointer dereference. What happens is: CPU0 CPU1 idle() arch_idle() tick_broadcast_oneshot_control(OFF); set cpu1 in tick_broadcast_force_mask if (cpu_offline()) arch_cpu_dead() cpu_dead_cleanup(cpu1) cpu1 tickdevice pointer = NULL broadcast interrupt dereference cpu1 tickdevice pointer -> OOPS We dereference the pointer because cpu1 is still set in tick_broadcast_force_mask and tick_do_broadcast() expects a valid cpumask and therefor lacks any further checks. Remove the cpu from the tick_broadcast_force_mask before we set the tick device pointer to NULL. Also add a sanity check to the oneshot broadcast function, so we can detect such issues w/o crashing the machine. Reported-by: Prarit Bhargava <prarit@redhat.com> Cc: athorlton@sgi.com Cc: CAI Qian <caiqian@redhat.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1306261303260.4013@ionos.tec.linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-07-02modules: don't fail to load on unknown parameters.Rusty Russell
Although parameters are supposed to be part of the kernel API, experimental parameters are often removed. In addition, downgrading a kernel might cause previously-working modules to fail to load. On balance, it's probably better to warn, and load the module anyway. This may let through a typo, but at least the logs will show it. Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-07-02There is no /sys/parametersJean Delvare
There is no such path as /sys/parameters, module parameters live in /sys/module/*/parameters. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-07-02module: don't modify argument of module_kallsyms_lookup_name()Mathias Krause
If we pass a pointer to a const string in the form "module:symbol" module_kallsyms_lookup_name() will try to split the string at the colon, i.e., will try to modify r/o data. That will, in fact, fail on a kernel with enabled CONFIG_DEBUG_RODATA. Avoid modifying the passed string in module_kallsyms_lookup_name(), modify find_module_all() instead to pass it the module name length. Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-07-01Merge tag 'v3.10' into sched/coreIngo Molnar
Merge in a recent upstream commit: c2853c8df57f include/linux/math64.h: add div64_ul() because: 72a4cf20cb71 sched: Change cfs_rq load avg to unsigned long relies on it. [ We don't rebase sched/core for this, because the handful of followup commits after the broken commit are not behavioral changes so are unlikely to be needed during bisection. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-29cgroup: CGRP_ROOT_SUBSYS_BOUND should also be ignored when mounting an ↵Tejun Heo
existing hierarchy 0ce6cba357 ("cgroup: CGRP_ROOT_SUBSYS_BOUND should be ignored when comparing mount options") only updated the remount path but CGRP_ROOT_SUBSYS_BOUND should also be ignored when comparing options while mounting an existing hierarchy. As option mismatch triggers a warning but doesn't fail the mount without sane_behavior, this only triggers a spurious warning message. Fix it by only comparing CGRP_ROOT_OPTION_MASK bits when comparing new and existing root options. Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-29Fix: kernel/ptrace.c: ptrace_peek_siginfo() missing __put_user() validationMathieu Desnoyers
This __put_user() could be used by unprivileged processes to write into kernel memory. The issue here is that even if copy_siginfo_to_user() fails, the error code is not checked before __put_user() is executed. Luckily, ptrace_peek_siginfo() has been added within the 3.10-rc cycle, so it has not hit a stable release yet. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: Roland McGrath <roland@redhat.com> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com> Cc: Dave Jones <davej@redhat.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Pedro Alves <palves@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-06-29Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "Correct an ordering issue in the tick broadcast code. I really wish we'd get compensation for pain and suffering for each line of code we write to work around dysfunctional timer hardware." * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick: Fix tick_broadcast_pending_mask not cleared
2013-06-29Merge branch 'pm-assorted'Rafael J. Wysocki
* pm-assorted: PM / Sleep: Warn about system time after resume with pm_trace
2013-06-28timekeeping: Indicate that clock was set in the pvclock gtod notifierDavid Vrabel
If the clock was set (stepped), set the action parameter to functions in the pvclock gtod notifier chain to non-zero. This allows the callee to only do work if the clock was stepped. This will be used on Xen as the synchronization of the Xen wallclock to the control domain's (dom0) system time will be done with this notifier and updating on every timer tick is unnecessary and too expensive. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/1372329348-20841-4-git-send-email-david.vrabel@citrix.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28timekeeping: Pass flags instead of multiple bools to timekeeping_update()David Vrabel
Instead of passing multiple bools to timekeeping_updated(), define flags and use a single 'action' parameter. It is then more obvious what each timekeeping_update() call does. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/1372329348-20841-3-git-send-email-david.vrabel@citrix.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28hrtimers: Support resuming with two or more CPUs online (but stopped)David Vrabel
hrtimers_resume() only reprograms the timers for the current CPU as it assumes that all other CPUs are offline at this point in the resume process. If other CPUs are online then their timers will not be corrected and they may fire at the wrong time. When running as a Xen guest, this assumption is not true. Non-boot CPUs are only stopped with IRQs disabled instead of offlining them. This is a performance optimization as disabling the CPUs would add an unacceptable amount of additional downtime during a live migration (> 200 ms for a 4 VCPU guest). hrtimers_resume() cannot call on_each_cpu(retrigger_next_event,...) as the other CPUs will be stopped with IRQs disabled. Instead, defer the call to the next softirq. [ tglx: Separated the xen change out ] Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/1372329348-20841-2-git-send-email-david.vrabel@citrix.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28timer: Fix jiffies wrap behavior of round_jiffies_common()Bart Van Assche
Direct compare of jiffies related values does not work in the wrap around case. Replace it with time_is_after_jiffies(). Signed-off-by: Bart Van Assche <bvanassche@acm.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/519BC066.5080600@acm.org Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28softirq: Use _RET_IP_Davidlohr Bueso
Use the already defined macro to pass the function return address. Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/1367347569.1784.3.camel@buesod1.americas.hpqcorp.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28sched/debug: Remove CONFIG_FAIR_GROUP_SCHED maskAlex Shi
Now that we are using runnable load avg in sched balance, we don't need to keep it under CONFIG_FAIR_GROUP_SCHED. Also align the code style to #ifdef instead of #if defined() and reorder the tg output info. Signed-off-by: Alex Shi <alex.shi@intel.com> Cc: pjt@google.com Cc: kamalesh@linux.vnet.ibm.com Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/1372417835-4698-1-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-28Merge branch 'pm-assorted'Rafael J. Wysocki
* pm-assorted: PM / QoS: Add pm_qos and dev_pm_qos to events-power.txt PM / QoS: Add dev_pm_qos_request tracepoints PM / QoS: Add pm_qos_request tracepoints PM / QoS: Add pm_qos_update_target/flags tracepoints PM / QoS: Update Documentation/power/pm_qos_interface.txt PM / Sleep: Print last wakeup source on failed wakeup_count write PM / QoS: correct the valid range of pm_qos_class PM / wakeup: Adjust messaging for wake events during suspend PM / Runtime: Update .runtime_idle() callback documentation PM / Runtime: Rework the "runtime idle" helper routine PM / Hibernate: print physical addresses consistently with other parts of kernel
2013-06-28Merge branch 'freezer'Rafael J. Wysocki
* freezer: af_unix: use freezable blocking calls in read sigtimedwait: use freezable blocking call nanosleep: use freezable blocking call futex: use freezable blocking call select: use freezable blocking call epoll: use freezable blocking call binder: use freezable blocking calls freezer: add new freezable helpers using freezer_do_not_count() freezer: convert freezable helpers to static inline where possible freezer: convert freezable helpers to freezer_do_not_count() freezer: skip waking up tasks with PF_FREEZER_SKIP set freezer: shorten freezer sleep time using exponential backoff lockdep: check that no locks held at freeze time lockdep: remove task argument from debug_check_no_locks_held freezer: add unsafe versions of freezable helpers for CIFS freezer: add unsafe versions of freezable helpers for NFS
2013-06-28genirq: Add the generic chip to the genirq docbookThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Randy Dunlap <rdunlap@infradead.org>
2013-06-28genirq: generic-chip: Export some irq_gc_ functionsFabio Estevam
When building imx_v6_v7_defconfig with imx-drm drivers selected as modules, we get the following build errors: ERROR: "irq_gc_mask_clr_bit" [drivers/staging/imx-drm/ipu-v3/imx-ipu-v3.ko] undefined! ERROR: "irq_gc_mask_set_bit" [drivers/staging/imx-drm/ipu-v3/imx-ipu-v3.ko] undefined! ERROR: "irq_gc_ack_set_bit" [drivers/staging/imx-drm/ipu-v3/imx-ipu-v3.ko] undefined! Export the required functions to avoid this problem. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Cc: shawn.guo@linaro.org Cc: kernel@pengutronix.de Link: http://lkml.kernel.org/r/1372389789-7048-1-git-send-email-festevam@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28genirq: Fix can_request_irq() for IRQs without an actionBen Hutchings
Commit 02725e7471b8 ('genirq: Use irq_get/put functions'), inadvertently changed can_request_irq() to return 0 for IRQs that have no action. This causes pcibios_lookup_irq() to select only IRQs that already have an action with IRQF_SHARED set, or to fail if there are none. Change can_request_irq() to return 1 for IRQs that have no action (if the first two conditions are met). Reported-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is> Tested-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is> (against 3.2) Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: 709647@bugs.debian.org Cc: stable@vger.kernel.org # 2.6.39+ Link: http://bugs.debian.org/709647 Link: http://lkml.kernel.org/r/1372383630.23847.40.camel@deadeye.wl.decadent.org.uk Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-06-28sched/debug: Fix formatting of /proc/<PID>/schedKamalesh Babulal
This patch alters format string's width, to align all statistics at par with the longest struct sched_statistic member name under /proc/<PID>/sched. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20130627165005.GA15583@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-28cgroup: CGRP_ROOT_SUBSYS_BOUND should be ignored when comparing mount optionsTejun Heo
1672d04070 ("cgroup: fix cgroupfs_root early destruction path") introduced CGRP_ROOT_SUBSYS_BOUND which is used to mark completion of subsys binding on a new root; however, this broke remounts. cgroup_remount() doesn't allow changing root options via remount and CGRP_ROOT_SUBSYS_BOUND, which is set on all fully initialized roots, makes the function reject all remounts. Fix it by putting the options part in the lower 16 bits of root->flags and masking the comparions. While at it, make cgroup_remount() emit an error message explaining why it's rejecting a remount request, so that it's less of a mystery. Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-28cgroup: fix deadlock on cgroup_mutex via drop_parsed_module_refcounts()Tejun Heo
eb178d06332 ("cgroup: grab cgroup_mutex in drop_parsed_module_refcounts()") made drop_parsed_module_refcounts() grab cgroup_mutex to make lockdep assertion in for_each_subsys() happy. Unfortunately, cgroup_remount() calls the function while holding cgroup_mutex in its failure path leading to the following deadlock. # mount -t cgroup -o remount,memory,blkio cgroup blkio cgroup: option changes via remount are deprecated (pid=525 comm=mount) ============================================= [ INFO: possible recursive locking detected ] 3.10.0-rc4-work+ #1 Not tainted --------------------------------------------- mount/525 is trying to acquire lock: (cgroup_mutex){+.+.+.}, at: [<ffffffff8110a3e1>] drop_parsed_module_refcounts+0x21/0xb0 but task is already holding lock: (cgroup_mutex){+.+.+.}, at: [<ffffffff8110e4e1>] cgroup_remount+0x51/0x200 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(cgroup_mutex); lock(cgroup_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by mount/525: #0: (&type->s_umount_key#30){+.+...}, at: [<ffffffff811e9a0d>] do_mount+0x2bd/0xa30 #1: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<ffffffff8110e4d3>] cgroup_remount+0x43/0x200 #2: (cgroup_mutex){+.+.+.}, at: [<ffffffff8110e4e1>] cgroup_remount+0x51/0x200 #3: (cgroup_root_mutex){+.+.+.}, at: [<ffffffff8110e4ef>] cgroup_remount+0x5f/0x200 stack backtrace: CPU: 2 PID: 525 Comm: mount Not tainted 3.10.0-rc4-work+ #1 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 ffffffff829651f0 ffff88000ec2fc28 ffffffff81c24bb1 ffff88000ec2fce8 ffffffff810f420d 0000000000000006 0000000000000001 0000000000000056 ffff8800153b4640 ffff880000000000 ffffffff81c2e468 ffff8800153b4640 Call Trace: [<ffffffff81c24bb1>] dump_stack+0x19/0x1b [<ffffffff810f420d>] __lock_acquire+0x15dd/0x1e60 [<ffffffff810f531c>] lock_acquire+0x9c/0x1f0 [<ffffffff81c2a805>] mutex_lock_nested+0x65/0x410 [<ffffffff8110a3e1>] drop_parsed_module_refcounts+0x21/0xb0 [<ffffffff8110e63e>] cgroup_remount+0x1ae/0x200 [<ffffffff811c9bb2>] do_remount_sb+0x82/0x190 [<ffffffff811e9d41>] do_mount+0x5f1/0xa30 [<ffffffff811ea203>] SyS_mount+0x83/0xc0 [<ffffffff81c2fb82>] system_call_fastpath+0x16/0x1b Fix it by moving the drop_parsed_module_refcounts() invocation outside cgroup_mutex. Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-27PM / Sleep: Warn about system time after resume with pm_traceShuah Khan
pm_trace uses the system's Real Time Clock (RTC) to save the magic number. The reason for this is that the RTC is the only reliably available piece of hardware during resume operations where a value can be set that will survive a reboot. Consequence is that after a resume (even if it is successful) your system clock will have a value corresponding to the magic number instead of the correct date/time! It is therefore advisable to use a program like ntp-date or rdate to reset the correct date/time from an external time source when using this trace option. There is no run-time message to warn users of the consequences of enabling pm_trace. Adding a warning message to pm_trace_store() will serve as a reminder to users to set the system date and time after resume. Signed-off-by: Shuah Khan <shuah.kh@samsung.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-27sched/fair: Fix typo describing flags in enqueue_entityKamalesh Babulal
Fix spelling of 'calling' in description of se flags in enqueue_entity(). Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Cc: peterz@infradead.org Link: http://lkml.kernel.org/r/20130627055418.GA18582@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/debug: Add load-tracking statistics to taskKamalesh Babulal
At present we print per-entity load-tracking statistics for cfs_rq of cgroups/runqueues. Given that per task statistics is maintained, it can be used to know the contribution made by the task to its parenting cfs_rq level. This patch adds per-task load-tracking statistics to /proc/<PID>/sched. Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130625080336.GA20175@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Change get_rq_runnable_load() to static and inlineAlex Shi
Based-on-patch-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-14-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/tg: Remove tg.load_weightAlex Shi
Since no one use it. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-13-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/cfs_rq: Change atomic64_t removed_load to atomic_long_tAlex Shi
Similar to runnable_load_avg, blocked_load_avg variable, long type is enough for removed_load in 64 bit or 32 bit machine. Then we avoid the expensive atomic64 operations on 32 bit machine. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-12-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched/tg: Use 'unsigned long' for load variable in task groupAlex Shi
Since tg->load_avg is smaller than tg->load_weight, we don't need a atomic64_t variable for load_avg in 32 bit machine. The same reason for cfs_rq->tg_load_contrib. The atomic_long_t/unsigned long variable type are more efficient and convenience for them. Signed-off-by: Alex Shi <alex.shi@intel.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-11-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Change cfs_rq load avg to unsigned longAlex Shi
Since the 'u64 runnable_load_avg, blocked_load_avg' in cfs_rq struct are smaller than 'unsigned long' cfs_rq->load.weight. We don't need u64 vaiables to describe them. unsigned long is more efficient and convenience. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-10-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Consider runnable load average in move_tasks()Alex Shi
Aside from using runnable load average in background, move_tasks is also the key function in load balance. We need consider the runnable load average in it in order to make it an apple to apple load comparison. Morten had caught a div u64 bug on ARM, thanks! Thanks-to: Morten Rasmussen <morten.rasmussen@arm.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-8-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Compute runnable load avg in cpu_load and cpu_avg_load_per_taskAlex Shi
They are the base values in load balance, update them with rq runnable load average, then the load balance will consider runnable load avg naturally. We also try to include the blocked_load_avg as cpu load in balancing, but that cause kbuild performance drop 6% on every Intel machine, and aim7/oltp drop on some of 4 CPU sockets machines. Or only add blocked_load_avg into get_rq_runable_load, hackbench still drop a little on NHM EX. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-7-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Update cpu load after task_tickAlex Shi
To get the latest runnable info, we need do this cpuload update after task_tick. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-6-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Fix sleep time double accounting in enqueue entityAlex Shi
The woken migrated task will __synchronize_entity_decay(se); in migrate_task_rq_fair, then it needs to set `se->avg.last_runnable_update -= (-se->avg.decay_count) << 20' before update_entity_load_avg, in order to avoid sleep time is updated twice for se.avg.load_avg_contrib in both __syncchronize and update_entity_load_avg. However if the sleeping task is woken up from the same cpu, it miss the last_runnable_update before update_entity_load_avg(se, 0, 1), then the sleep time was used twice in both functions. So we need to remove the double sleep time accounting. Paul also contributed some code comments in this commit. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Paul Turner <pjt@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-5-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-27sched: Set an initial value of runnable avg for new forked taskAlex Shi
We need to initialize the se.avg.{decay_count, load_avg_contrib} for a new forked task. Otherwise random values of above variables cause a mess when a new task is enqueued: enqueue_task_fair enqueue_entity enqueue_entity_load_avg and make fork balancing imbalance due to incorrect load_avg_contrib. Further more, Morten Rasmussen notice some tasks were not launched at once after created. So Paul and Peter suggest giving a start value for new task runnable avg time same as sched_slice(). PeterZ said: > So the 'problem' is that our running avg is a 'floating' average; ie. it > decays with time. Now we have to guess about the future of our newly > spawned task -- something that is nigh impossible seeing these CPU > vendors keep refusing to implement the crystal ball instruction. > > So there's two asymptotic cases we want to deal well with; 1) the case > where the newly spawned program will be 'nearly' idle for its lifetime; > and 2) the case where its cpu-bound. > > Since we have to guess, we'll go for worst case and assume its > cpu-bound; now we don't want to make the avg so heavy adjusting to the > near-idle case takes forever. We want to be able to quickly adjust and > lower our running avg. > > Now we also don't want to make our avg too light, such that it gets > decremented just for the new task not having had a chance to run yet -- > even if when it would run, it would be more cpu-bound than not. > > So what we do is we make the initial avg of the same duration as that we > guess it takes to run each task on the system at least once -- aka > sched_slice(). > > Of course we can defeat this with wakeup/fork bombs, but in the 'normal' > case it should be good enough. Paul also contributed most of the code comments in this commit. Signed-off-by: Alex Shi <alex.shi@intel.com> Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Reviewed-by: Paul Turner <pjt@google.com> [peterz; added explanation of sched_slice() usage] Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1371694737-29336-4-git-send-email-alex.shi@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>