- 23 Sep, 2012 22 commits
-
-
Paul E. McKenney authored
The current quiescent-state detection algorithm is needlessly complex. It records the grace-period number corresponding to the quiescent state at the time of the quiescent state, which works, but it seems better to simply erase any record of previous quiescent states at the time that the CPU notices the new grace period. This has the further advantage of removing another piece of RCU for which lockless reasoning is required. Therefore, this commit makes this change. Signed-off-by:
Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by:
Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by:
Josh Triplett <josh@joshtriplett.org>
-
Paul E. McKenney authored
The synchronize_rcu_expedited() function disables interrupts across a scan of all leaf rcu_node structures, which is not good for real-time scheduling latency on large systems (hundreds or especially thousands of CPUs). This commit therefore holds off CPU-hotplug operations using get_online_cpus(), and removes the prior acquisiion of the ->onofflock (which required disabling interrupts). Signed-off-by:
-
Paul E. McKenney authored
In the C language, signed overflow is undefined. It is true that twos-complement arithmetic normally comes to the rescue, but if the compiler can subvert this any time it has any information about the values being compared. For example, given "if (a - b > 0)", if the compiler has enough information to realize that (for example) the value of "a" is positive and that of "b" is negative, the compiler is within its rights to optimize to a simple "if (1)", which might not be what you want. This commit therefore converts synchronize_rcu_expedited()'s work-done detection counter from signed to unsigned. Signed-off-by:
-
Paul E. McKenney authored
Now that the rcu_node structures' ->completed fields are unconditionally assigned at grace-period cleanup time, they should already have the correct value for the new grace period at grace-period initialization time. This commit therefore inserts a WARN_ON_ONCE() to verify this invariant. Signed-off-by:
-
Paul E. McKenney authored
Preemption greatly raised the probability of certain types of race conditions, so this commit adds an anti-heisenbug to greatly increase the collision cross section, also known as the probability of occurrence. Signed-off-by:
-
Paul E. McKenney authored
The current approach to grace-period initialization is vulnerable to extremely low-probability races. These races stem from the fact that the old grace period is marked completed on the same traversal through the rcu_node structure that is marking the start of the new grace period. This means that some rcu_node structures will believe that the old grace period is still in effect at the same time that other rcu_node structures believe that the new grace period has already started. These sorts of disagreements can result in too-short grace periods, as shown in the following scenario: 1. CPU 0 completes a grace period, but needs an additional grace period, so starts initializing one, initializing all the non-leaf rcu_node structures and the first leaf rcu_node structure. Because CPU 0 is both completing the old grace period and starting a new one, it marks the completion of the old grace period and the start of the new grace period in a single traversal of the rcu_node structures. Therefore, CPUs corresponding to the first rcu_node structure can become aware that the prior grace period has completed, but CPUs corresponding to the other rcu_node structures will see this same prior grace period as still being in progress. 2. CPU 1 passes through a quiescent state, and therefore informs the RCU core. Because its leaf rcu_node structure has already been initialized, this CPU's quiescent state is applied to the new (and only partially initialized) grace period. 3. CPU 1 enters an RCU read-side critical section and acquires a reference to data item A. Note that this CPU believes that its critical section started after the beginning of the new grace period, and therefore will not block this new grace period. 4. CPU 16 exits dyntick-idle mode. Because it was in dyntick-idle mode, other CPUs informed the RCU core of its extended quiescent state for the past several grace periods. This means that CPU 16 is not yet aware that these past grace periods have ended. Assume that CPU 16 corresponds to the second leaf rcu_node structure -- which has not yet been made aware of the new grace period. 5. CPU 16 removes data item A from its enclosing data structure and passes it to call_rcu(), which queues a callback in the RCU_NEXT_TAIL segment of the callback queue. 6. CPU 16 enters the RCU core, possibly because it has taken a scheduling-clock interrupt, or alternatively because it has more than 10,000 callbacks queued. It notes that the second most recent grace period has completed (recall that because it corresponds to the second as-yet-uninitialized rcu_node structure, it cannot yet become aware that the most recent grace period has completed), and therefore advances its callbacks. The callback for data item A is therefore in the RCU_NEXT_READY_TAIL segment of the callback queue. 7. CPU 0 completes initialization of the remaining leaf rcu_node structures for the new grace period, including the structure corresponding to CPU 16. 8. CPU 16 again enters the RCU core, again, possibly because it has taken a scheduling-clock interrupt, or alternatively because it now has more than 10,000 callbacks queued. It notes that the most recent grace period has ended, and therefore advances its callbacks. The callback for data item A is therefore in the RCU_DONE_TAIL segment of the callback queue. 9. All CPUs other than CPU 1 pass through quiescent states. Because CPU 1 already passed through its quiescent state, the new grace period completes. Note that CPU 1 is still in its RCU read-side critical section, still referencing data item A. 10. Suppose that CPU 2 wais the last CPU to pass through a quiescent state for the new grace period, and suppose further that CPU 2 did not have any callbacks queued, therefore not needing an additional grace period. CPU 2 therefore traverses all of the rcu_node structures, marking the new grace period as completed, but does not initialize a new grace period. 11. CPU 16 yet again enters the RCU core, yet again possibly because it has taken a scheduling-clock interrupt, or alternatively because it now has more than 10,000 callbacks queued. It notes that the new grace period has ended, and therefore advances its callbacks. The callback for data item A is therefore in the RCU_DONE_TAIL segment of the callback queue. This means that this callback is now considered ready to be invoked. 12. CPU 16 invokes the callback, freeing data item A while CPU 1 is still referencing it. This scenario represents a day-zero bug for TREE_RCU. This commit therefore ensures that the old grace period is marked completed in all leaf rcu_node structures before a new grace period is marked started in any of them. That said, it would have been insanely difficult to force this race to happen before the grace-period initialization process was preemptible. Therefore, this commit is not a candidate for -stable. Signed-off-by:
-
Paul E. McKenney authored
The module parameters blimit, qhimark, and qlomark (and more recently, rcu_fanout_leaf) have permission masks of zero, so that their values are not visible from sysfs. This is unnecessary and inconvenient to administrators who might like an easy way to see what these values are on a running system. This commit therefore sets their permission masks to 0444, allowing them to be read but not written. Reported-by:
Rusty Russell <rusty@ozlabs.org> Reported-by:
-
Paul E. McKenney authored
Although almost everyone is well-served by the defaults, some uses of RCU benefit from shorter grace periods, while others benefit more from the greater efficiency provided by longer grace periods. Situations requiring a large number of grace periods to elapse (and wireshark startup has been called out as an example of this) are helped by lower-latency grace periods. Furthermore, in some embedded applications, people are willing to accept a small degradation in update efficiency (due to there being more of the shorter grace-period operations) in order to gain the lower latency. In contrast, those few systems with thousands of CPUs need longer grace periods because the CPU overhead of a grace period rises roughly linearly with the number of CPUs. Such systems normally do not make much use of facilities that require large numbers of grace periods to elapse, so this is a good tradeoff. Therefore, this commit allows the durations to be controlled from sysfs. There are two sysfs parameters, one named "jiffies_till_first_fqs" that specifies the delay in jiffies from the end of grace-period initialization until the first attempt to force quiescent states, and the other named "jiffies_till_next_fqs" that specifies the delay (again in jiffies) between subsequent attempts to force quiescent states. They both default to three jiffies, which is compatible with the old hard-coded behavior. At some future time, it may be possible to automatically increase the grace-period length with the number of CPUs, but we do not yet have sufficient data to do a good job. Preliminary data indicates that we should add an addiitonal jiffy to each of the delays for every 200 CPUs in the system, but more experimentation is needed. For now, the number of systems with more than 1,000 CPUs is small enough that this can be relegated to boot-time hand tuning. Signed-off-by:
-
Paul E. McKenney authored
Large systems running RCU_FAST_NO_HZ kernels see extreme memory contention on the rcu_state structure's ->fqslock field. This can be avoided by disabling RCU_FAST_NO_HZ, either at compile time or at boot time (via the nohz kernel boot parameter), but large systems will no doubt become sensitive to energy consumption. This commit therefore uses a combining-tree approach to spread the memory contention across new cache lines in the leaf rcu_node structures. This can be thought of as a tournament lock that has only a try-lock acquisition primitive. The effect on small systems is minimal, because such systems have an rcu_node "tree" consisting of a single node. In addition, this functionality is not used on fastpaths. Signed-off-by:
-
Paul E. McKenney authored
Moving quiescent-state forcing into a kthread dispenses with the need for the ->n_rp_need_fqs field, so this commit removes it. Signed-off-by:
-
Paul E. McKenney authored
RCU quiescent-state forcing is currently carried out without preemption points, which can result in excessive latency spikes on large systems (many hundreds or thousands of CPUs). This patch therefore inserts a voluntary preemption point into force_qs_rnp(), which should greatly reduce the magnitude of these spikes. Reported-by:
Mike Galbraith <mgalbraith@suse.de> Reported-by:
Dimitri Sivanich <sivanich@sgi.com> Signed-off-by:
-
Paul E. McKenney authored
As the first step towards allowing quiescent-state forcing to be preemptible, this commit moves RCU quiescent-state forcing into the same kthread that is now used to initialize and clean up after grace periods. This is yet another step towards keeping scheduling latency down to a dull roar. Updated to change from raw_spin_lock_irqsave() to raw_spin_lock_irq() and to remove the now-unused rcu_state structure fields as suggested by Peter Zijlstra. Reported-by:
-
Dimitri Sivanich authored
The fields in the rcu_state structure that are protected by the root rcu_node structure's ->lock can share a cache line with the fields protected by ->onofflock. This can result in excessive memory contention on large systems, so this commit applies ____cacheline_internodealigned_in_smp to the ->onofflock field in order to segregate them. Signed-off-by:
-
Paul E. McKenney authored
In kernels built with CONFIG_RCU_FAST_NO_HZ=y, CPUs can accumulate a large number of lazy callbacks, which as the name implies will be slow to be invoked. This can be a problem on small-memory systems, where the default 6-second sleep for CPUs having only lazy RCU callbacks could well be fatal. This commit therefore installs an OOM hander that ensures that every CPU with lazy callbacks has at least one non-lazy callback, in turn ensuring timely advancement for these callbacks. Updated to fix bug that disabled OOM killing, noted by Lai Jiangshan. Updated to push the for_each_rcu_flavor() loop into rcu_oom_notify_cpu(), thus reducing the number of IPIs, as suggested by Steven Rostedt. Also to make the for_each_online_cpu() loop be preemptible. (Later, it might be good to use smp_call_function(), as suggested by Peter Zijlstra.) Signed-off-by:
Sasha Levin <levinsasha928@gmail.com> Reviewed-by:
-
Paul E. McKenney authored
Earlier versions of RCU invoked the RCU core from the CPU_DYING notifier in order to note a quiescent state for the outgoing CPU. Because the CPU is marked "offline" during the execution of the CPU_DYING notifiers, the RCU core had to tolerate being invoked from an offline CPU. However, commit b1420f1c (Make rcu_barrier() less disruptive) left only tracing code in the CPU_DYING notifier, so the RCU core need no longer execute on offline CPUs. This commit therefore enforces this restriction. Signed-off-by:
-
Paul E. McKenney authored
Then rcu_gp_kthread() function is too large and furthermore needs to have the force_quiescent_state() code pulled in. This commit therefore breaks up rcu_gp_kthread() into rcu_gp_init() and rcu_gp_cleanup(). Signed-off-by:
-
Paul E. McKenney authored
RCU grace-period cleanup is currently carried out with interrupts disabled, which can result in excessive latency spikes on large systems (many hundreds or thousands of CPUs). This patch therefore makes the RCU grace-period cleanup be preemptible, including voluntary preemption points, which should eliminate those latency spikes. Similar spikes from forcing of quiescent states will be dealt with similarly by later patches. Updated to replace uses of spin_lock_irqsave() with spin_lock_irq(), as suggested by Peter Zijlstra. Reported-by:
-
Paul E. McKenney authored
As a first step towards allowing grace-period cleanup to be preemptible, this commit moves the RCU grace-period cleanup into the same kthread that is now used to initialize grace periods. This is needed to keep scheduling latency down to a dull roar. [ paulmck: Get rid of stray spin_lock_irqsave() calls. ] Reported-by:
-
Paul E. McKenney authored
RCU grace-period initialization is currently carried out with interrupts disabled, which can result in 200-microsecond latency spikes on systems on which RCU has been configured for 4096 CPUs. This patch therefore makes the RCU grace-period initialization be preemptible, which should eliminate those latency spikes. Similar spikes from grace-period cleanup and the forcing of quiescent states will be dealt with similarly by later patches. Reported-by:
-
Paul E. McKenney authored
The next step in reducing RCU's grace-period initialization latency on large systems will make this initialization preemptible. Unfortunately, making the grace-period initialization subject to interrupts (let alone preemption) exposes the following race on systems whose rcu_node tree contains more than one node: 1. CPU 31 starts initializing the grace period, including the first leaf rcu_node structures, and is then preempted. 2. CPU 0 refers to the first leaf rcu_node structure, and notes that a new grace period has started. It passes through a quiescent state shortly thereafter, and informs the RCU core of this rite of passage. 3. CPU 0 enters an RCU read-side critical section, acquiring a pointer to an RCU-protected data item. 4. CPU 31 takes an interrupt whose handler removes the data item referenced by CPU 0 from the data structure, and registers an RCU callback in order to free it. 5. CPU 31 resumes initializing the grace period, including its own rcu_node structure. In invokes rcu_start_gp_per_cpu(), which advances all callbacks, including the one registered in #4 above, to be handled by the current grace period. 6. The remaining CPUs pass through quiescent states and inform the RCU core, but CPU 0 remains in its RCU read-side critical section, still referencing the now-removed data item. 7. The grace period completes and all the callbacks are invoked, including the one that frees the data item that CPU 0 is still referencing. Oops!!! One way to avoid this race is to remove grace-period acceleration from rcu_start_gp_per_cpu(). Now, the only reason for this acceleration was to allow CPUs bringing RCU out of idle state to have their callbacks invoked after only one grace period, rather than the two grace periods that would otherwise be required. But this acceleration does not work when RCU grace-period initialization is moved to a kthread because the CPU posting the callback is no longer necessarily the CPU that is initializing the resulting grace period. This commit therefore removes this now-pointless (and soon to be dangerous) grace-period acceleration, thus avoiding the above race. Signed-off-by: -
Paul E. McKenney authored
As the first step towards allowing grace-period initialization to be preemptible, this commit moves the RCU grace-period initialization into its own kthread. This is needed to keep large-system scheduling latency at reasonable levels. Also change raw_spin_lock_irqsave() to raw_spin_lock_irq() as suggested by Peter Zijlstra in review comments. Reported-by:
-
Paul E. McKenney authored
Each grace period is supposed to have at least one callback waiting for that grace period to complete. However, if CONFIG_NO_HZ=n, an extra callback-free grace period is no big problem -- it will chew up a tiny bit of CPU time, but it will complete normally. In contrast, CONFIG_NO_HZ=y kernels have the potential for all the CPUs to go to sleep indefinitely, in turn indefinitely delaying completion of the callback-free grace period. Given that nothing is waiting on this grace period, this is also not a problem. That is, unless RCU CPU stall warnings are also enabled, as they are in recent kernels. In this case, if a CPU wakes up after at least one minute of inactivity, an RCU CPU stall warning will result. The reason that no one noticed until quite recently is that most systems have enough OS noise that they will never remain absolutely idle for a full minute. But there are some embedded systems with cut-down userspace configurations that consistently get into this situation. All this begs the question of exactly how a callback-free grace period gets started in the first place. This can happen due to the fact that CPUs do not necessarily agree on which grace period is in progress. If a CPU still believes that the grace period that just completed is still ongoing, it will believe that it has callbacks that need to wait for another grace period, never mind the fact that the grace period that they were waiting for just completed. This CPU can therefore erroneously decide to start a new grace period. Note that this can happen in TREE_RCU and TREE_PREEMPT_RCU even on a single-CPU system: Deadlock considerations mean that the CPU that detected the end of the grace period is not necessarily officially informed of this fact for some time. Once this CPU notices that the earlier grace period completed, it will invoke its callbacks. It then won't have any callbacks left. If no other CPU has any callbacks, we now have a callback-free grace period. This commit therefore makes CPUs check more carefully before starting a new grace period. This new check relies on an array of tail pointers into each CPU's list of callbacks. If the CPU is up to date on which grace periods have completed, it checks to see if any callbacks follow the RCU_DONE_TAIL segment, otherwise it checks to see if any callbacks follow the RCU_WAIT_TAIL segment. The reason that this works is that the RCU_WAIT_TAIL segment will be promoted to the RCU_DONE_TAIL segment as soon as the CPU is officially notified that the old grace period has ended. This change is to cpu_needs_another_gp(), which is called in a number of places. The only one that really matters is in rcu_start_gp(), where the root rcu_node structure's ->lock is held, which prevents any other CPU from starting or completing a grace period, so that the comparison that determines whether the CPU is missing the completion of a grace period is stable. Reported-by:
Becky Bruce <bgillbruce@gmail.com> Reported-by:
Subodh Nijsure <snijsure@grid-net.com> Reported-by:
Paul Walmsley <paul@pwsan.com> Signed-off-by:
-
- 12 Sep, 2012 1 commit
-
-
Josh Triplett authored
Tracepoints declare a static inline trace_*_rcuidle variant of the trace function, to support safely generating trace events from the idle loop. Module code never actually uses that variant of trace functions, because modules don't run code that needs tracing with RCU idled. However, the declaration of those otherwise unused functions causes the module to reference rcu_idle_exit and rcu_idle_enter, which RCU does not export to modules. To avoid this, don't generate trace_*_rcuidle functions for tracepoints declared in module code. Link: http://lkml.kernel.org/r/20120905062306.GA14756@leafReported-by:
Steven Rostedt <rostedt@goodmis.org> Acked-by:
Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by:
-
- 08 Sep, 2012 3 commits
-
-
Linus Torvalds authored
-
git://git.linaro.org/people/mszyprowski/linux-dma-mappingLinus Torvalds authored
Pull DMA-mapping fixes from Marek Szyprowski: "Another set of fixes for ARM dma-mapping subsystem. Commit e9da6e99 replaced custom consistent buffer remapping code with generic vmalloc areas. It however introduced some regressions caused by limited support for allocations in atomic context. This series contains fixes for those regressions. For some subplatforms the default, pre-allocated pool for atomic allocations turned out to be too small, so a function for setting its size has been added. Another set of patches adds support for atomic allocations to IOMMU-aware DMA-mapping implementation. The last part of this pull request contains two fixes for Contiguous Memory Allocator, which relax too strict requirements." * 'fixes-for-3.6' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: ARM: dma-mapping: IOMMU allocates pages from atomic_pool with GFP_ATOMIC ARM: dma-mapping: Introduce __atomic_get_pages() for __iommu_get_pages() ARM: dma-mapping: Refactor out to introduce __in_atomic_pool ARM: dma-mapping: atomic_pool with struct page **pages ARM: Kirkwood: increase atomic coherent pool size ARM: DMA-Mapping: print warning when atomic coherent allocation fails ARM: DMA-Mapping: add function for setting coherent pool size from platform code ARM: relax conditions required for enabling Contiguous Memory Allocator mm: cma: fix alignment requirements for contiguous regions
-
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds authored
Pull input subsystem updates from Dmitry Torokhov. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: wacom - add support for EMR on Cintiq 24HD touch Input: i8042 - add Gigabyte T1005 series netbooks to noloop table Input: imx_keypad - reset the hardware before enabling Input: edt-ft5x06 - fix build error when compiling wthout CONFIG_DEBUG_FS
-
- 07 Sep, 2012 4 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hidLinus Torvalds authored
Pull HID updates from Jiri Kosina: "It contains a fix for Eaton Ellipse MAX UPS from Alan Stern, performance improvement (not processing debug data if noone is interested), by Henrik Rydberg, and allowing tpkbd-driven devices to work even with generic driver in a crippled mode, by Andres Freund." * 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: HID: tpkbd: work even if the new Lenovo Keyboard driver is not configured HID: Only dump input if someone is listening HID: add NOGET quirk for Eaton Ellipse MAX UPS
-
Andres Freund authored
c1dcad2d added a new driver configured by HID_LENOVO_TPKBD but made the hid_have_special_driver entry non-optional which lead to a recognized but non-working device if the new driver wasn't configured (which is the correct default). Signed-off-by:
Andres Freund <andres@anarazel.de> Signed-off-by:
Jiri Kosina <jkosina@suse.cz>
-
Linus Torvalds authored
Merge tag 'stable/for-linus-3.6-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen bug-fixes from Konrad Rzeszutek Wilk: * Fix for TLB flushing introduced in v3.6 * Fix Xen-SWIOTLB not using proper DMA mask - device had 64bit but in a 32-bit kernel we need to allocate for coherent pages from a 32-bit pool. * When trying to re-use P2M nodes we had a one-off error and triggered a BUG_ON check with specific CONFIG_ option. * When doing FLR in Xen-PCI-backend we would first do FLR then save the PCI configuration space. We needed to do it the other way around. * tag 'stable/for-linus-3.6-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pciback: Fix proper FLR steps. xen: Use correct masking in xen_swiotlb_alloc_coherent. xen: fix logical error in tlb flushing xen/p2m: Fix one-off error in checking the P2M tree directory.
-
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pciLinus Torvalds authored
Pull PCI updates from Bjorn Helgaas: "Power management - PCI/PM: Enable D3/D3cold by default for most devices - PCI/PM: Keep parent bridge active when probing device - PCI/PM: Fix config reg access for D3cold and bridge suspending - PCI/PM: Add ABI document for sysfs file d3cold_allowed Core - PCI: Don't print anything while decoding is disabled" * tag '3.6-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI: Don't print anything while decoding is disabled PCI/PM: Add ABI document for sysfs file d3cold_allowed PCI/PM: Fix config reg access for D3cold and bridge suspending PCI/PM: Keep parent bridge active when probing device PCI/PM: Enable D3/D3cold by default for most devices
-
- 06 Sep, 2012 10 commits
-
-
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds authored
Pull ARM SoC bug fixes from Olof Johansson: "Mostly Renesas and Atmel bugfixes this time, targeting boot and build problems. A couple of patches for gemini and kirkwood as well. On a whole nothing very controversial." * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ARM: gemini: fix the gemini build ARM: shmobile: armadillo800eva: enable rw rootfs mount ARM: Kirkwood: Fix 'SZ_1M' undeclared here for db88f6281-bp-setup.c ARM: shmobile: mackerel: fixup usb module order ARM: shmobile: armadillo800eva: fixup: sound card detection order ARM: shmobile: marzen: fixup smsc911x id for regulator ARM: at91/feature-removal-schedule: delay at91_mci removal ARM: mach-shmobile: armadillo800eva: Enable power button as wakeup source ARM: mach-shmobile: armadillo800eva: Fix GPIO buttons descriptions ARM: at91/dts: remove partial parameter in at91sam9g25ek.dts ARM: at91/clock: fix PLLA overclock warning ARM: at91: fix rtc-at91sam9 irq issue due to sparse irq support ARM: at91: fix system timer irq issue due to sparse irq support ARM: shmobile: sh73a0: fixup RELOC_BASE of intca_irq_pins_desc
-
git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-stagingLinus Torvalds authored
Pull a hwmon fix from Guenter Roeck: "One patch, fixing DIV_ROUND_CLOSEST to support negative dividends. While the changes are not in the drivers/hwmon directory, the problem primarily affects hwmon drivers, and it makes sense to push the patch through the hwmon tree." * tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: linux/kernel.h: Fix DIV_ROUND_CLOSEST to support negative dividends
-
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuildLinus Torvalds authored
Pull kbuild fixes from Michal Marek: "These are two fixes that should go into 3.6. The link-vmlinux.sh one is obvious. The other one fixes make firmware_install with certain configurations, where a file in the toplevel firmware tree gets installed first, and $(INSTALL_FW_PATH)/$$(dir <file>) results in /lib/firmware/./, which confuses make 3.82 for some reason." * 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: firmware: fix directory creation rule matching with make 3.82 link-vmlinux.sh: Fix stray "echo" in error message
-
Dave Jones authored
Trivially triggerable, found by trinity: kernel BUG at mm/mempolicy.c:2546! Process trinity-child2 (pid: 23988, threadinfo ffff88010197e000, task ffff88007821a670) Call Trace: show_numa_map+0xd5/0x450 show_pid_numa_map+0x13/0x20 traverse+0xf2/0x230 seq_read+0x34b/0x3e0 vfs_read+0xac/0x180 sys_pread64+0xa2/0xc0 system_call_fastpath+0x1a/0x1f RIP: mpol_to_str+0x156/0x360 Cc: stable@vger.kernel.org Signed-off-by:Dave Jones <davej@redhat.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Konrad Rzeszutek Wilk authored
When we do FLR and save PCI config we did it in the wrong order. The end result was that if a PCI device was unbind from its driver, then binded to xen-pciback, and then back to its driver we would get: > lspci -s 04:00.0 04:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection 13:42:12 # 4 :~/ > echo "0000:04:00.0" > /sys/bus/pci/drivers/pciback/unbind > modprobe e1000e e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:04:00.0: Disabling ASPM L0s L1 e1000e 0000:04:00.0: enabling device (0000 -> 0002) xen: registering gsi 48 triggering 0 polarity 1 Already setup the GSI :48 e1000e 0000:04:00.0: Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e: probe of 0000:04:00.0 failed with error -2 This fixes it by first saving the PCI configuration space, then doing the FLR. Reported-by:
Ren, Yongjie <yongjie.ren@intel.com> Reported-and-Tested-by:
Tobias Geiger <tobias.geiger@vido.info> Signed-off-by:
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: stable@vger.kernel.org
-
git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmcLinus Torvalds authored
Pull MMC fixes from Chris Ball: - a firmware bug on several Samsung MoviNAND eMMC models causes permanent corruption on the device when secure erase and secure trim requests are made, so we disable those requests on these eMMC devices. - atmel-mci: fix a hang with some SD cards by waiting for not-busy flag. - dw_mmc: low-power mode breaks SDIO interrupts; fix PIO error handling; fix handling of error interrupts. - mxs-mmc: fix deadlocks; fix compile error due to dma.h arch change. - omap: fix broken PIO mode causing memory corruption. - sdhci-esdhc: fix card detection. * tag 'mmc-fixes-for-3.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: mmc: omap: fix broken PIO mode mmc: card: Skip secure erase on MoviNAND; causes unrecoverable corruption. mmc: dw_mmc: Disable low power mode if SDIO interrupts are used mmc: dw_mmc: fix error handling in PIO mode mmc: dw_mmc: correct mishandling error interrupt mmc: dw_mmc: amend using error interrupt status mmc: atmel-mci: not busy flag has also to be used for read operations mmc: sdhci-esdhc: break out early if clock is 0 mmc: mxs-mmc: fix deadlock caused by recursion loop mmc: mxs-mmc: fix deadlock in SDIO IRQ case mmc: bfin_sdh: fix dma_desc_array build error
-
Miklos Szeredi authored
Fix the following compile error on UML. arch/um/os-Linux/time.c: In function 'deliver_alarm': arch/um/os-Linux/time.c:117:3: error: too few arguments to function 'alarm_handler' arch/um/os-Linux/internal.h:1:6: note: declared here The error was introduced by commit d3c1cfcd ("um: pass siginfo to guest process") in 3.6-rc1. Signed-off-by:
Miklos Szeredi <mszeredi@suse.cz> CC: Martin Pärtel <martin.partel@gmail.com> Signed-off-by:
-
Alan Cox authored
Allocate a structure not a pointer to it ! Signed-off-by:
Alan Cox <alan@linux.intel.com> Signed-off-by:
-
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpcLinus Torvalds authored
Pull powerpc fixes from Benjamin Herrenschmidt: "Here are a few fixes for 3.6 that were piling up while I was away or busy (I was mostly MIA a week or two before San Diego). Some fixes from Anton fixing up issues with our relatively new DSCR control feature, and a few other fixes that are either regressions or bugs nasty enough to warrant not waiting." * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc: Don't use __put_user() in patch_instruction powerpc: Make sure IPI handlers see data written by IPI senders powerpc: Restore correct DSCR in context switch powerpc: Fix DSCR inheritance in copy_thread() powerpc: Keep thread.dscr and thread.dscr_inherit in sync powerpc: Update DSCR on all CPUs when writing sysfs dscr_default powerpc/powernv: Always go into nap mode when CPU is offline powerpc: Give hypervisor decrementer interrupts their own handler powerpc/vphn: Fix arch_update_cpu_topology() return value
-
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds authored
Pull GPIO fixes from Linus Walleij: "These are some GPIO regression fixes for v3.6: - Erroneous debug message from of_get_named_gpio_flags() - Make sure the MC9S08DZ60 GPIO driver depend on I2C being compiled in (not module) or allmodconfig breaks. - Check return value from irq_alloc_descs() in the Emma Mobile GPIO driver. - Assign the owner field for the rdc321x driver so the module won't be removed if it has active GPIOs." * tag 'gpio-fixes-for-v3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: gpio: rdc321x: Prevent removal of modules exporting active GPIOs gpio: em: Fix checking return value of irq_alloc_descs gpio: mc9s08dz60: Fix build error if I2C=m gpio: Fix debug message in of_get_named_gpio_flags()
-
