- 30 Sep, 2013 10 commits
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Manfred Spraul authored
The exclusion of complex operations in sem_lock() is insufficient: after acquiring the per-semaphore lock, a simple op must first check that sem_perm.lock is not locked and only after that test check complex_count. The current code does it the other way around - and that creates a race. Details are below. The patch is a complete rewrite of sem_lock(), based in part on the code from Mike Galbraith. It removes all gotos and all loops and thus the risk of livelocks. I have tested the patch (together with the next one) on my i3 laptop and it didn't cause any problems. The bug is probably also present in 3.10 and 3.11, but for these kernels it might be simpler just to move the test of sma->complex_count after the spin_is_locked() test. Details of the bug: Assume: - sma->complex_count = 0. - Thread 1: semtimedop(complex op that must sleep) - Thread 2: semtimedop(simple op). Pseudo-Trace: Thread 1: sem_lock(): acquire sem_perm.lock Thread 1: sem_lock(): check for ongoing simple ops Nothing ongoing, thread 2 is still before sem_lock(). Thread 1: try_atomic_semop() <<< preempted. Thread 2: sem_lock(): static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, int nsops) { int locknum; again: if (nsops == 1 && !sma->complex_count) { struct sem *sem = sma->sem_base + sops->sem_num; /* Lock just the semaphore we are interested in. */ spin_lock(&sem->lock); /* * If sma->complex_count was set while we were spinning, * we may need to look at things we did not lock here. */ if (unlikely(sma->complex_count)) { spin_unlock(&sem->lock); goto lock_array; } <<<<<<<<< <<< complex_count is still 0. <<< <<< Here it is preempted <<<<<<<<< Thread 1: try_atomic_semop() returns, notices that it must sleep. Thread 1: increases sma->complex_count. Thread 1: drops sem_perm.lock Thread 2: /* * Another process is holding the global lock on the * sem_array; we cannot enter our critical section, * but have to wait for the global lock to be released. */ if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { spin_unlock(&sem->lock); spin_unlock_wait(&sma->sem_perm.lock); goto again; } <<< sem_perm.lock already dropped, thus no "goto again;" locknum = sops->sem_num; Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Cc: Mike Galbraith <bitbucket@online.de> Cc: Rik van Riel <riel@redhat.com> Cc: Davidlohr Bueso <davidlohr.bueso@hp.com> Cc: <stable@vger.kernel.org> [3.10+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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David Rientjes authored
We've been getting warnings about an excessive amount of time spent allocating pages for migration during memory compaction without scheduling. isolate_freepages_block() already periodically checks for contended locks or the need to schedule, but isolate_freepages() never does. When a zone is massively long and no suitable targets can be found, this iteration can be quite expensive without ever doing cond_resched(). Check periodically for the need to reschedule while the compaction free scanner iterates. Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Dan Aloni authored
A high setting of max_map_count, and a process core-dumping with a large enough vm_map_count could result in an NT_FILE note not being written, and the kernel crashing immediately later because it has assumed otherwise. Reproduction of the oops-causing bug described here: https://lkml.org/lkml/2013/8/30/50 Rge ussue originated in commit 2aa362c4 ("coredump: extend core dump note section to contain file names of mapped file") from Oct 4, 2012. This patch make that section optional in that case. fill_files_note() should signify the error, and also let the info struct in elf_core_dump() be zero-initialized so that we can check for the optionally written note. [akpm@linux-foundation.org: avoid abusing E2BIG, remove a couple of not-really-needed local variables] [akpm@linux-foundation.org: fix sparse warning] Signed-off-by: Dan Aloni <alonid@stratoscale.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Denys Vlasenko <vda.linux@googlemail.com> Reported-by: Martin MOKREJS <mmokrejs@gmail.com> Tested-by: Martin MOKREJS <mmokrejs@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joonyoung Shim authored
This reverts commit cea27eb2 ("mm/memory-hotplug: fix lowmem count overflow when offline pages"). The fixed bug by commit cea27eb2 was fixed to another way by commit 3dcc0571 ("mm: correctly update zone->managed_pages"). That commit enhances memory_hotplug.c to adjust totalhigh_pages when hot-removing memory, for details please refer to: http://marc.info/?l=linux-mm&m=136957578620221&w=2 As a result, commit cea27eb2 currently causes duplicated decreasing of totalhigh_pages, thus the revert. Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32Linus Torvalds authored
Pull AVR32 fixes from Hans-Christian Egtvedt. Fix build warnings and use the Kbuild infrastructure for generic headers rather than doing it by hand. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32: avr32: cast syscall_return to silence compiler warning avr32: fix clockevents kernel warning avr32: use Kbuild infrastructure to handle the asm-generic headers
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git://github.com/sctscore/official-linuxLinus Torvalds authored
Pull S+core fixes from Lennox Wu: "These updates include updating information of maintainers, fix some trivial errors, and add a necessary function for supporting ipv6" * tag 'for-linus-20130929' of git://github.com/sctscore/official-linux: Score: Update the information of Score maintaners Score: Modify the Makefile of Score, remove -mlong-calls for compiling Score: Implement the function csum_ipv6_magic Score: The commit is for compiling successfully
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git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arcLinus Torvalds authored
Pull ARC Fixes from Vineet Gupta: - Handle unaligned access in zero delay loops - spinlock livelock fix for SMP systemC model - fix 32bit overflow in access_ok - better setup of clockevents * tag 'arc-fixes-for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: Use clockevents_config_and_register over clockevents_register_device ARC: Workaround spinlock livelock in SMP SystemC simulation ARC: Fix 32-bit wrap around in access_ok() ARC: Handle zero-overhead-loop in unaligned access handler
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Gabor Juhos authored
The patch fixes the following compiler warning: CC arch/avr32/kernel/process.o arch/avr32/kernel/process.c: In function 'copy_thread': arch/avr32/kernel/process.c:292: warning: assignment makes integer \ from pointer without a cast Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
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Gabor Juhos authored
Since commit 01426478 (avr32: Use generic idle loop) the kernel throws the following warning on avr32: WARNING: at 900322e4 [verbose debug info unavailable] Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 3.12.0-rc2 #117 task: 901c3ecc ti: 901c0000 task.ti: 901c0000 PC is at cpu_idle_poll_ctrl+0x1c/0x38 LR is at comparator_mode+0x3e/0x40 pc : [<900322e4>] lr : [<90014882>] Not tainted sp : 901c1f74 r12: 00000000 r11: 901c74a0 r10: 901d2510 r9 : 00000001 r8 : 901db4de r7 : 901c74a0 r6 : 00000001 r5 : 00410020 r4 : 901db574 r3 : 00410024 r2 : 90206fe0 r1 : 00000000 r0 : 007f0000 Flags: qvnzc Mode bits: hjmde....G CPU Mode: Supervisor Call trace: [<90039ede>] clockevents_set_mode+0x16/0x2e [<90039f00>] clockevents_shutdown+0xa/0x1e [<9003a078>] clockevents_exchange_device+0x58/0x70 [<9003a78c>] tick_check_new_device+0x38/0x54 [<9003a1a2>] clockevents_register_device+0x32/0x90 [<900035c4>] time_init+0xa8/0x108 [<90000520>] start_kernel+0x128/0x23c When the 'avr32_comparator' clockevent device is registered, the clockevent core sets the mode of that clockevent device to CLOCK_EVT_MODE_SHUTDOWN. Due to this, the 'comparator_mode' function calls the 'cpu_idle_poll_ctrl' to disables idle poll. This results in the aforementioned warning because the polling is not enabled yet. Change the code to only disable idle poll if it is enabled by the same function to avoid the warning. Cc: stable@vger.kernel.org Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
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Steven Rostedt authored
Use kbuild to add asm-generic headers that do nothing, also remove the arch specific wrapper headers. This only affects headers that do nothing but include the generic equivalent. It does not touch any header that does a little more. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
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- 29 Sep, 2013 10 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usbLinus Torvalds authored
Pull USB fixes from Greg KH: "Here are a number of USB driver fixes for 3.12-rc3. These are all for host controller issues that have been reported, and there's a fix for an annoying error message that gets printed every time you remove a USB 3 device from the system that's been bugging me for a while" * tag 'usb-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: usb: dwc3: add support for Merrifield USB: fsl/ehci: fix failure of checking PHY_CLK_VALID during reinitialization USB: Fix breakage in ffs_fs_mount() fsl/usb: Resolve PHY_CLK_VLD instability issue for ULPI phy usb/core/devio.c: Don't reject control message to endpoint with wrong direction bit usb: chipidea: USB_CHIPIDEA should depend on HAS_DMA usb: chipidea: udc: free pending TD at removal procedure usb: chipidea: imx: Add usb_phy_shutdown at probe's error path usb: chipidea: Fix memleak for ci->hw_bank.regmap when removal usb: chipidea: udc: fix the oops after rmmod gadget USB: fix PM config symbol in uhci-hcd, ehci-hcd, and xhci-hcd USB: OHCI: accept very late isochronous URBs USB: UHCI: accept very late isochronous URBs USB: iMX21: accept very late isochronous URBs usbcore: check usb device's state before sending a Set SEL control transfer xhci: Fix race between ep halt and URB cancellation usb: Fix xHCI host issues on remote wakeup. xhci: Ensure a command structure points to the correct trb on the command ring xhci: Fix oops happening after address device timeout
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/ttyLinus Torvalds authored
Pull tty/serial fixes from Greg KH: "Here are some serial at tty driver fixes for 3.12-rc3 The serial driver fixes some kref leaks, documentation is moved to the proper places, and the tty and n_tty fixes resolve some reported regressions. There is still one outstanding tty regression fix that isn't in here yet, as I want to test it out some more, it will be sent for 3.12-rc4 if it checks out" * tag 'tty-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: tty: ar933x_uart: move devicetree binding documentation tty: Fix SIGTTOU not sent with tcflush() n_tty: Fix EOF push index when termios changes serial: pch_uart: remove unnecessary tty_port_tty_get serial: pch_uart: fix tty-kref leak in dma-rx path serial: pch_uart: fix tty-kref leak in rx-error path serial: tegra: fix tty-kref leak
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/stagingLinus Torvalds authored
Pull staging fixes from Greg KH: "Here are some staging driver fixes, MAINTAINER updates, and a new device id. All of these have been in the linux-next tree, and are pretty simple patches" * tag 'staging-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: r8188eu: Add new device ID staging: imx-drm: Fix probe failure staging: vt6656: [BUG] iwctl_siwencodeext return if device not open staging: vt6656: [BUG] main_usb.c oops on device_close move flag earlier. staging: vt6656: rxtx.c [BUG] s_vGetFreeContext dead lock on null apTD. Staging: rtl8192u: r819xU_cmdpkt: checking NULL value after doing dev_alloc_skb staging: usbip: Orphan usbip staging: r8188eu: Add files for new drive: Cocci spatch "noderef" staging: r8188eu: Cocci spatch "noderef" staging: octeon-usb: Cocci spatch "noderef" staging: r8188eu: Add files for new drive: Cocci spatch "noderef" MAINTAINERS: staging: dgnc and dgap drivers: add maintainer staging: lustre: Cocci spatch "noderef"
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Linus Torvalds authored
Merge tag 'driver-core-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core / sysfs fixes from Greg KH: "Here are 2 fixes for 3.12-rc3. One fixes a sysfs problem with mounting caused by 3.12-rc1, and the other is a bug reported by the chromeos developers with the driver core. Both have been in linux-next for a bit" * tag 'driver-core-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: driver core : Fix use after free of dev->parent in device_shutdown sysfs: Allow mounting without CONFIG_NET
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-miscLinus Torvalds authored
Pull char/misc driver fixes from Greg KH: "Here are some HyperV and MEI driver fixes for 3.12-rc3. They resolve some issues that people have been reporting for them" * tag 'char-misc-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: Drivers: hv: vmbus: Terminate vmbus version negotiation on timeout Drivers: hv: util: Correctly support ws2008R2 and earlier mei: cancel stall timers in mei_reset mei: bus: stop wait for read during cl state transition mei: make me client counters less error prone
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull perf revert from Ingo Molnar: "This fixes the 'perf top' regression Markus Trippelsdorf reported" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "perf symbols: Demangle cloned functions"
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git://people.freedesktop.org/~airlied/linuxLinus Torvalds authored
Pull drm fixes from Dave Airlie: "Nothing too major, radeon still has some dpm changes for off by default. Radeon, intel, msm: - radeon: a few more dpm fixes (still off by default), uvd fixes - i915: runtime warn backtrace and regression fix - msm: iommu changes fallout" * 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (27 commits) drm/msm: use drm_gem_dumb_destroy helper drm/msm: deal with mach/iommu.h removal drm/msm: Remove iommu include from mdp4_kms.c drm/msm: Odd PTR_ERR usage drm/i915: Fix up usage of SHRINK_STOP drm/radeon: fix hdmi audio on DCE3.0/3.1 asics drm/i915: preserve pipe A quirk in i9xx_set_pipeconf drm/i915/tv: clear adjusted_mode.flags drm/i915/dp: increase i2c-over-aux retry interval on AUX DEFER drm/radeon/cik: fix overflow in vram fetch drm/radeon: add missing hdmi callbacks for rv6xx drm/i915: Use a temporary va_list for two-pass string handling drm/radeon/uvd: lower msg&fb buffer requirements on UVD3 drm/radeon: disable tests/benchmarks if accel is disabled drm/radeon: don't set default clocks for SI when DPM is disabled drm/radeon/dpm/ci: filter clocks based on voltage/clk dep tables drm/radeon/dpm/si: filter clocks based on voltage/clk dep tables drm/radeon/dpm/ni: filter clocks based on voltage/clk dep tables drm/radeon/dpm/btc: filter clocks based on voltage/clk dep tables drm/radeon/dpm: fetch the max clk from voltage dep tables helper ...
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Ingo Molnar authored
This reverts commit de95ab53. Markus Trippelsdorf reported that this commit broke 'perf top': > I just see a gray screen with no text at all. Sometimes the > following error messages are printed: > > *** Error in `perf': invalid fastbin entry (free): 0x00000000029b18c0 > *** > *** Error in `perf': malloc(): memory corruption (fast): 0x0000000000ee0b10 *** While this code is fixable, the commit itself fails on several levels: - it should have been a separate helper function - why the heck does it do strchr() twice - it casts a const char * over into char * - sloppy style - it's not even a regression fix! So lets revert it and re-try the patch in v3.13. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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git://people.freedesktop.org/~robclark/linuxDave Airlie authored
A small fix + deal with fallout of iommu changes + use new drm_gem_dumb_destroy helper. * 'msm-fixes-3.12-rc2' of git://people.freedesktop.org/~robclark/linux: drm/msm: use drm_gem_dumb_destroy helper drm/msm: deal with mach/iommu.h removal drm/msm: Remove iommu include from mdp4_kms.c drm/msm: Odd PTR_ERR usage
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- 28 Sep, 2013 20 commits
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Linus Torvalds authored
Merge branches 'sched-urgent-for-linus', 'timers-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler, timer and x86 fixes from Ingo Molnar: - A context tracking ARM build and functional fix - A handful of ARM clocksource/clockevent driver fixes - An AMD microcode patch level sysfs reporting fixlet * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arm: Fix build error with context tracking calls * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: em_sti: Set cpu_possible_mask to fix SMP broadcast clocksource: of: Respect device tree node status clocksource: exynos_mct: Set IRQ affinity when the CPU goes online arm: clocksource: mvebu: Use the main timer as clock source from DT * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/AMD: Fix patch level reporting for family 15h
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull perf fixes from Ingo Molnar: "A couple of tooling fixlets and a PMU detection printout fix" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86: Fix PMU detection printout when no PMU is detected perf symbols: Demangle cloned functions perf machine: Fix path unpopulated in machine__create_modules() perf tools: Explicitly add libdl dependency perf probe: Fix probing symbols with optimization suffix perf trace: Add mmap2 handler perf kmem: Make it work again on non NUMA machines
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git://oss.sgi.com/xfs/xfsLinus Torvalds authored
Pull xfs bugfixes from Ben Myers: - fix for directory node collapse regression - fix for recovery over stale on disk structures - fix for eofblocks ioctl - fix asserts in xfs_inode_free - lock the ail before removing an item from it * tag 'xfs-for-linus-v3.12-rc3' of git://oss.sgi.com/xfs/xfs: xfs: fix node forward in xfs_node_toosmall xfs: log recovery lsn ordering needs uuid check xfs: fix XFS_IOC_FREE_EOFBLOCKS definition xfs: asserting lock not held during freeing not valid xfs: lock the AIL before removing the buffer item
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git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds authored
Pull i2c fixes from Wolfram Sang: "Some driver bugfixes for the I2C subsystem" * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: ismt: initialize DMA buffer i2c: designware: 10-bit addressing mode enabling if I2C_DYNAMIC_TAR_UPDATE is set i2c: mv64xxx: Do not use writel_relaxed() i2c: mv64xxx: Fix some build warnings i2c: s3c2410: fix clk_disable/clk_unprepare WARNings
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds authored
Pull ACPI and power management fixes from Rafael Wysocki: "These fix one recent cpufreq regression, a few older bugs that may harm users and a kerneldoc typo. Specifics: 1) After the recent locking changes in the cpufreq core it is possible to trigger BUG_ON(!policy) in lock_policy_rwsem_read() if cpufreq_get() is called before registering a cpufreq driver. Fix from Viresh Kumar. 2) If intel_pstate has been loaded already, it doesn't make sense to do anything in acpi_cpufreq_init() and moreover doing something in there in that case may be harmful, so make that function return immediately if another cpufreq driver is already present. From Yinghai Lu. 3) The ACPI IPMI driver sometimes attempts to acquire a mutex from interrupt context, which can be avoided by replacing that mutex with a spinlock. From Lv Zheng. 4) A NULL pointer may be dereferenced by the exynos5440 cpufreq driver if a memory allocation made by it fails. Fix from Sachin Kamat. 5) Hanjun Guo's commit fixes a typo in the kerneldoc comment documenting acpi_bus_unregister_driver()" * tag 'pm+acpi-3.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI / scan: fix typo in comments of acpi_bus_unregister_driver() cpufreq: exynos5440: Fix potential NULL pointer dereference cpufreq: check cpufreq driver is valid and cpufreq isn't disabled in cpufreq_get() acpi-cpufreq: skip loading acpi_cpufreq after intel_pstate ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler()
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Yinghai Lu authored
Ben Herrenschmidt found that commit 928bea96 ("PCI: Delay enabling bridges until they're needed") breaks PCI in some powerpc environments. The reason is that the PCIe port driver will call pci_enable_device() on the bridge, so the device is enabled, but skips pci_set_master because pcie_port_auto and no acpi on powerpc. Because of that, pci_enable_bridge() later on (called as a result of the child device driver doing pci_enable_device) will see the bridge as already enabled and will not call pci_set_master() on it. Fixed by add checking in pci_enable_bridge, and call pci_set_master if driver skip that. That will make the code more robot and wade off problem for missing pci_set_master in drivers. Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds authored
Pull s390 lockref enablement from Heiko Carstens: "Enabling the new lockless lockref variant on s390 would have been trivial until Tony Luck added a cpu_relax() call into the CMPXCHG_LOOP(), with commit d472d9d9 ("lockref: Relax in cmpxchg loop") As already mentioned cpu_relax() is very expensive on s390 since it yields() the current virtual cpu. So we are talking of several thousand cycles. Considering this enabling the lockless lockref variant would contradict the intention of the new semantics. And also some quick measurements show performance regressions of 50% and more. Simply removing the cpu_relax() call again seems also not very desireable since Waiman Long reported that for some workloads the call improved performance by 5%." * 'lockref' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390: enable ARCH_USE_CMPXCHG_LOCKREF lockref: use arch_mutex_cpu_relax() in CMPXCHG_LOOP() mutex: replace CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX with simple ifdef
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Jean Delvare authored
Commit 6072ddc8 ("kernel: replace strict_strto*() with kstrto*()") broke the handling of signed integer types, fix it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Reported-by: Christian Kujau <lists@nerdbynature.de> Tested-by: Christian Kujau <lists@nerdbynature.de> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/robh/linuxLinus Torvalds authored
Pull DeviceTree fixes from Rob Herring: "Clean-up to fix some warnings for !OF builds and spelling fixes in docs: - Clean-up openrisc prom.h - Fix warnings caused by of_irq.h ifdefs - Spelling fix for Synopsys" * tag 'devicetree-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: dts: Fix misspelling of Synopsys of: clean-up ifdefs in of_irq.h openrisc: clean-up prom.h
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git://git.linaro.org/people/rmk/linux-armLinus Torvalds authored
Pull ARM fixes from Russell King: "Just a few relatively small ARM fixes found since the last merge window, nothing too exciting" * 'fixes' of git://git.linaro.org/people/rmk/linux-arm: ARM: 7837/3: fix Thumb-2 bug in AES assembler code ARM: only allow kernel mode neon with AEABI ARM: 7839/1: entry: fix tracing of ARM-private syscalls ARM: 7836/1: add __get_user_unaligned/__put_user_unaligned
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James Ralston authored
This patch adds code to initialize the DMA buffer to compensate for possible hardware data corruption. Signed-off-by: James Ralston <james.d.ralston@intel.com> [wsa: changed to use 'sizeof'] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Rob Clark authored
Signed-off-by: Rob Clark <robdclark@gmail.com>
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Rob Clark authored
We still need an API exported by msm iommu driver (but not visible in any public header anymore). For now, just declare the prototype ourselves, but when msm iommu driver provides a better option, use that instead. Signed-off-by: Rob Clark <robdclark@gmail.com>
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Ingo Molnar authored
Ran into this cryptic PMU bootup log recently: [ 0.124047] Performance Events: [ 0.125000] smpboot: ... Turns out we print this if no PMU is detected. Fall back to the right condition so that the following is printed: [ 0.122381] Performance Events: no PMU driver, software events only. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Link: http://lkml.kernel.org/n/tip-u2fwaUffakjp0qkpRfqljgsn@git.kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Joerg Roedel authored
The include file has been removed and the file does not need it anyway, so remove it. Fixes a compile error. Signed-off-by: Joerg Roedel <joro@8bytes.org> Signed-off-by: Rob Clark <robdclark@gmail.com>
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Thomas Meyer authored
The variable priv->kms is not initialized yet. Found by "scripts/coccinelle/tests/odd_ptr_err.cocci". PTR_ERR should access the value just tested by IS_ERR. Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
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Heiko Carstens authored
Enable ARCH_USE_CMPXCHG_LOCKREF since it shows performance improvements with Linus' simple stat() test case of up to 50% on a 30 cpu system. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Heiko Carstens authored
Make use of arch_mutex_cpu_relax() so architectures can override the default cpu_relax() semantics. This is especially useful for s390, where cpu_relax() means that we yield() the current (virtual) cpu and therefore is very expensive, and would contradict the whole purpose of the lockless cmpxchg loop. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Heiko Carstens authored
Linus suggested to replace #ifndef CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX #define arch_mutex_cpu_relax() cpu_relax() #endif with just a simple #ifndef arch_mutex_cpu_relax # define arch_mutex_cpu_relax() cpu_relax() #endif to get rid of CONFIG_HAVE_CPU_RELAX_SIMPLE. So architectures can simply define arch_mutex_cpu_relax if they want an architecture specific function instead of having to add a select statement in their Kconfig in addition. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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Ingo Molnar authored
Merge branch 'context_tracking/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into sched/urgent Pull context tracking ARM fix from Frederic Weisbecker. Signed-off-by: Ingo Molnar <mingo@kernel.org>
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