- 22 2月, 2014 4 次提交
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由 Stephane Eranian 提交于
This patch adds the PCI ids for the Intel SandyBridge, IvyBridge, Haswell Client memory controller (IMC). Cc: mingo@elte.hu Cc: acme@redhat.com Cc: ak@linux.intel.com Cc: zheng.z.yan@intel.com Cc: peterz@infradead.org Signed-off-by: NStephane Eranian <eranian@google.com> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1392132015-14521-4-git-send-email-eranian@google.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Stephane Eranian 提交于
This patch enables custom struct pmu callbacks per uncore PMU types. This feature may be used to simplify counter setup for certain uncore PMUs which have free running counters for instance. It becomes possible to bypass the event scheduling phase of the configuration. Cc: mingo@elte.hu Cc: acme@redhat.com Cc: ak@linux.intel.com Cc: zheng.z.yan@intel.com Cc: peterz@infradead.org Signed-off-by: NStephane Eranian <eranian@google.com> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1392132015-14521-3-git-send-email-eranian@google.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Stephane Eranian 提交于
On certain processors, the uncore PMU boxes may only be msr-bsed or PCI-based. But in both cases, the cpumask, suggesting on which CPUs to monitor to get full coverage of the particular PMU, must be created. However with the current code base, the cpumask was only created on processor which had at least one MSR-based uncore PMU. This patch removes that restriction and ensures the cpumask is created even when there is no msr-based PMU. For instance, on SNB client where only a PCI-based memory controller PMU is supported. Cc: mingo@elte.hu Cc: acme@redhat.com Cc: ak@linux.intel.com Cc: zheng.z.yan@intel.com Cc: peterz@infradead.org Signed-off-by: NStephane Eranian <eranian@google.com> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1392132015-14521-2-git-send-email-eranian@google.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Peter Zijlstra 提交于
On Mon, Feb 10, 2014 at 08:45:16AM -0800, Dave Hansen wrote: > The reason I coded this up was that NMIs were firing off so fast that > nothing else was getting a chance to run. With this patch, at least the > printk() would come out and I'd have some idea what was going on. It will start spewing to early_printk() (which is a lot nicer to use from NMI context too) when it fails to queue the IRQ-work because its already enqueued. It does have the false-positive for when two CPUs trigger the warn concurrently, but that should be rare and some extra clutter on the early printk shouldn't be a problem. Cc: hpa@zytor.com Cc: tglx@linutronix.de Cc: dzickus@redhat.com Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: mingo@kernel.org Fixes: 6a02ad66 ("perf/x86: Push the duration-logging printk() to IRQ context") Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140211150116.GO27965@twins.programming.kicks-ass.netSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 09 2月, 2014 12 次提交
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由 Don Zickus 提交于
A bunch of unknown NMIs have popped up on a Pentium4 recently when booting into a kdump kernel. This was exposed because the watchdog timer went from 60 seconds down to 10 seconds (increasing the ability to reproduce this problem). What is happening is on boot up of the second kernel (the kdump one), the previous nmi_watchdogs were enabled on thread 0 and thread 1. The second kernel only initializes one cpu but the perf counter on thread 1 still counts. Normally in a kdump scenario, the other cpus are blocking in an NMI loop, but more importantly their local apics have the performance counters disabled (iow LVTPC is masked). So any counters that fire are masked and never get through to the second kernel. However, on a P4 the local apic is shared by both threads and thread1's PMI (despite being configured to only interrupt thread1) will generate an NMI on thread0. Because thread0 knows nothing about this NMI, it is seen as an unknown NMI. This would be fine because it is a kdump kernel, strange things happen what is the big deal about a single unknown NMI. Unfortunately, the P4 comes with another quirk: clearing the overflow bit to prevent a stream of NMIs. This is the problem. The kdump kernel can not execute because of the endless NMIs that happen. To solve this, I instrumented the p4 perf init code, to walk all the counters and zero them out (just like a normal reset would). Now when the counters go off, they do not generate anything and no unknown NMIs are seen. I tested this on a P4 we have in our lab. After two or three crashes, I could normally reproduce the problem. Now after 10 crashes, everything continues to boot correctly. Signed-off-by: NDon Zickus <dzickus@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140120154115.GZ25953@redhat.com [ Fixed a stylistic detail. ] Signed-off-by: NIngo Molnar <mingo@kernel.org>
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由 Don Zickus 提交于
On a P4 box stressing perf with: ./perf record -o perf.data ./perf stat -v ./perf bench all it was noticed that a slew of unknown NMIs would pop out rather quickly. Painfully debugging this ancient platform, led me to notice cross cpu counter corruption. The P4 machine is special in that it has 18 counters, half are used for cpu0 and the other half is for cpu1 (or all 18 if hyperthreading is disabled). But the splitting of the counters has to be actively managed by the software. In this particular bug, one of the cpu0 specific counters was being used by cpu1 and caused all sorts of random unknown nmis. I am not entirely sure on the corruption path, but what happens is: o perf schedules a group with p4_pmu_schedule_events() o inside p4_pmu_schedule_events(), it notices an hwc pointer is being reused but for a different cpu, so it 'swaps' the config bits and returns the updated 'assign' array with a _new_ index. o perf schedules another group with p4_pmu_schedule_events() o inside p4_pmu_schedule_events(), it notices an hwc pointer is being reused (the same one as above) but for the _same_ cpu [BUG!!], so it updates the 'assign' array to use the _old_ (wrong cpu) index because the _new_ index is in an earlier part of the 'assign' array (and hasn't been committed yet). o perf commits the transaction using the wrong index and corrupts the other cpu The [BUG!!] is because the 'hwc->config' is updated but not the 'hwc->idx'. So the check for 'p4_should_swap_ts()' is correct the first time around but incorrect the second time around (because hwc->config was updated in between). I think the spirit of perf was to not modify anything until all the transactions had a chance to 'test' if they would succeed, and if so, commit atomically. However, P4 breaks this spirit by touching the hwc->config element. So my fix is to continue the un-perf like breakage, by assigning hwc->idx to -1 on swap to tell follow up group scheduling to find a new index. Of course if the transaction fails rolling this back will be difficult, but that is not different than how the current code works. :-) And I wasn't sure how much effort to cleanup the code I should do for a platform that is almost 10 years old by now. Hence the lazy fix. Signed-off-by: NDon Zickus <dzickus@redhat.com> Acked-by: NCyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1391024270-19469-1-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Peter Zijlstra 提交于
Calling printk() from NMI context is bad (TM), so move it to IRQ context. In doing so we slightly change (probably wreck) the debugfs nmi_longest_ns thingy, in that it doesn't update to reflect the longest, nor does writing to it reset the count. Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Cc: Don Zickus <dzickus@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Link: http://lkml.kernel.org/n/tip-rdw0au56a5ymis1u8p48c12d@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Peter Zijlstra 提交于
Calling printk() from NMI context is bad (TM), so move it to IRQ context. This also avoids the problem where the printk() time is measured by the generic NMI duration goo and triggers a second warning. Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Cc: Don Zickus <dzickus@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Link: http://lkml.kernel.org/n/tip-75dv35xf6dhhmeb7nq6fua31@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Ingo Molnar 提交于
Refresh the branch to a v3.14-rc base before queueing up new devel patches. Signed-off-by: NIngo Molnar <mingo@kernel.org>
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由 Peter Zijlstra 提交于
The current code forgets to change the CR4 state on the current CPU. Use on_each_cpu() instead of smp_call_function(). Reported-by: NMark Davies <junk@eslaf.co.uk> Suggested-by: NMark Davies <junk@eslaf.co.uk> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Cc: fweisbec@gmail.com Link: http://lkml.kernel.org/n/tip-69efsat90ibhnd577zy3z9gh@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Peter Zijlstra 提交于
PPro machines can die hard when PCE gets enabled due to a CPU erratum. The safe way it so disable it by default and keep it disabled. See erratum 26 in: http://download.intel.com/design/archives/processors/pro/docs/24268935.pdfReported-and-Tested-by: NMark Davies <junk@eslaf.co.uk> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vince@deater.net> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140206170815.GW2936@laptop.programming.kicks-ass.netSigned-off-by: NIngo Molnar <mingo@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl由 Linus Torvalds 提交于
Pull pinctrl fixes from Linus Walleij: "First round of pin control fixes for v3.14: - Protect pinctrl_list_add() with the proper mutex. This was identified by RedHat. Caused nasty locking warnings was rootcased by Stanislaw Gruszka. - Avoid adding dangerous debugfs files when either half of the subsystem is unused: pinmux or pinconf. - Various fixes to various drivers: locking, hardware particulars, DT parsing, error codes" * tag 'pinctrl-v3.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: pinctrl: tegra: return correct error type pinctrl: do not init debugfs entries for unimplemented functionalities pinctrl: protect pinctrl_list add pinctrl: sirf: correct the pin index of ac97_pins group pinctrl: imx27: fix offset calculation in imx_read_2bit pinctrl: vt8500: Change devicetree data parsing pinctrl: imx27: fix wrong offset to ICONFB pinctrl: at91: use locked variant of irq_set_handler
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip由 Linus Torvalds 提交于
Pull irq fix from Thomas Gleixner: "Add a missing Kconfig dependency" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Generic irq chip requires IRQ_DOMAIN
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip由 Linus Torvalds 提交于
Pull x86 fixes from Peter Anvin: "Quite a varied little collection of fixes. Most of them are relatively small or isolated; the biggest one is Mel Gorman's fixes for TLB range flushing. A couple of AMD-related fixes (including not crashing when given an invalid microcode image) and fix a crash when compiled with gcov" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode, AMD: Unify valid container checks x86, hweight: Fix BUG when booting with CONFIG_GCOV_PROFILE_ALL=y x86/efi: Allow mapping BGRT on x86-32 x86: Fix the initialization of physnode_map x86, cpu hotplug: Fix stack frame warning in check_irq_vectors_for_cpu_disable() x86/intel/mid: Fix X86_INTEL_MID dependencies arch/x86/mm/srat: Skip NUMA_NO_NODE while parsing SLIT mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridge x86: mm: change tlb_flushall_shift for IvyBridge x86/mm: Eliminate redundant page table walk during TLB range flushing x86/mm: Clean up inconsistencies when flushing TLB ranges mm, x86: Account for TLB flushes only when debugging x86/AMD/NB: Fix amd_set_subcaches() parameter type x86/quirks: Add workaround for AMD F16h Erratum792 x86, doc, kconfig: Fix dud URL for Microcode data
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git://github.com/kleikamp/linux-shaggy由 Linus Torvalds 提交于
Pull jfs fix from David Kleikamp: "Fix regression" * tag 'jfs-3.14-rc2' of git://github.com/kleikamp/linux-shaggy: jfs: fix generic posix ACL regression
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由 Dave Kleikamp 提交于
I missed a couple errors in reviewing the patches converting jfs to use the generic posix ACL function. Setting ACL's currently fails with -EOPNOTSUPP. Signed-off-by: NDave Kleikamp <dave.kleikamp@oracle.com> Reported-by: NMichael L. Semon <mlsemon35@gmail.com> Reviewed-by: NChristoph Hellwig <hch@lst.de>
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- 08 2月, 2014 15 次提交
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由 Richard Weinberger 提交于
On archs like S390 or um this driver cannot build nor work. Make it depend on HAS_IOMEM to bypass build failures. drivers/built-in.o: In function `dw_wdt_drv_probe': drivers/watchdog/dw_wdt.c:302: undefined reference to `devm_ioremap_resource' Signed-off-by: NRichard Weinberger <richard@nod.at> Signed-off-by: NWim Van Sebroeck <wim@iguana.be>
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由 Linus Torvalds 提交于
Merge tag 'driver-core-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fix from Greg KH: "Here is a single kernfs fix to resolve a much-reported lockdep issue with the removal of entries in sysfs" * tag 'driver-core-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag
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git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client由 Linus Torvalds 提交于
Pull ceph fixes from Sage Weil: "There is an RBD fix for a crash due to the immutable bio changes, an error path fix, and a locking fix in the recent redirect support" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: libceph: do not dereference a NULL bio pointer libceph: take map_sem for read in handle_reply() libceph: factor out logic from ceph_osdc_start_request() libceph: fix error handling in ceph_osdc_init()
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux由 Linus Torvalds 提交于
Pull arm64 fixes from Catalin Marinas: - Relax VDSO alignment requirements so that the kernel-picked one (4K) does not conflict with the dynamic linker's one (64K) - VDSO gettimeofday fix - Barrier fixes for atomic operations and cache flushing - TLB invalidation when overriding early page mappings during boot - Wired up new 32-bit arm (compat) syscalls - LSM_MMAP_MIN_ADDR when COMPAT is enabled - defconfig update - Clean-up (comments, pgd_alloc). * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: defconfig: Expand default enabled features arm64: asm: remove redundant "cc" clobbers arm64: atomics: fix use of acquire + release for full barrier semantics arm64: barriers: allow dsb macro to take option parameter security: select correct default LSM_MMAP_MIN_ADDR on arm on arm64 arm64: compat: Wire up new AArch32 syscalls arm64: vdso: update wtm fields for CLOCK_MONOTONIC_COARSE arm64: vdso: fix coarse clock handling arm64: simplify pgd_alloc arm64: fix typo: s/SERRROR/SERROR/ arm64: Invalidate the TLB when replacing pmd entries during boot arm64: Align CMA sizes to PAGE_SIZE arm64: add DSB after icache flush in __flush_icache_all() arm64: vdso: prevent ld from aligning PT_LOAD segments to 64k
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git://git.linux-mips.org/pub/scm/ralf/upstream-linus由 Linus Torvalds 提交于
Pull MIPS updates from Ralf Baechle: "hree minor patches. All have sat in -next for a few days" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: fpu.h: Fix build when CONFIG_BUG is not set MIPS: Wire up sched_setattr/sched_getattr syscalls MIPS: Alchemy: Fix DB1100 GPIO registration
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git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media由 Linus Torvalds 提交于
Pull media fixes from Mauro Carvalho Chehab: "A series of small fixes. Mostly driver ones. There is one core regression fix on a patch that was meant to fix some race issues on vb2, but that actually caused more harm than good. So, we're just reverting it for now" * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: [media] adv7842: Composite free-run platfrom-data fix [media] v4l2-dv-timings: fix GTF calculation [media] hdpvr: Fix memory leak in debug [media] af9035: add ID [2040:f900] Hauppauge WinTV-MiniStick 2 [media] mxl111sf: Fix compile when CONFIG_DVB_USB_MXL111SF is unset [media] mxl111sf: Fix unintentional garbage stack read [media] cx24117: use a valid dev pointer for dev_err printout [media] cx24117: remove dead code in always 'false' if statement [media] update Michael Krufky's email address [media] vb2: Check if there are buffers before streamon [media] Revert "[media] videobuf_vm_{open,close} race fixes" [media] go7007-loader: fix usb_dev leak [media] media: bt8xx: add missing put_device call [media] exynos4-is: Compile in fimc-lite runtime PM callbacks conditionally [media] exynos4-is: Compile in fimc runtime PM callbacks conditionally [media] exynos4-is: Fix error paths in probe() for !pm_runtime_enabled() [media] s5p-jpeg: Fix wrong NV12 format parameters [media] s5k5baf: allow to handle arbitrary long i2c sequences
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git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging由 Linus Torvalds 提交于
Pull hwmon fixes from Guenter Roeck: "Fix PMBus driver problem with some multi-page voltage sensors and fix da9055 interrupt initialization" * tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: hwmon: (da9055) Remove use of regmap_irq_get_virq() hwmon: (pmbus) Support per-page exponent in linear mode
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm由 Linus Torvalds 提交于
Pull ACPI and power management fixes from Rafael Wysocki: "These include a fix for a recent ACPI hotplug regression, four concurrency related fixes and one PCI device removal fix for ACPI-based PCI hotplug (ACPIPHP), intel_pstate fix that should go into stable, three simple ACPI cleanups and a new entry for the ACPI video blacklist. Specifics: - Fix for a recent ACPI hotplug regression causing a NULL pointer dereference to occur while handling ACPI eject notifications for already ejected devices. From Toshi Kani. - Four concurrency-related fixes for ACPIPHP. Two of them add missing locking and the other two fix race conditions related to reference counting. - ACPIPHP fix to avoid NULL pointer dereferences during device removal involving Virtual Funcions. - intel_pstate fix to make it compute the percentage of time the CPU is busy properly. From Dirk Brandewie. - Removal of two unnecessary NULL pointer checks in ACPI code and a fix for sscanf() format string from Dan Carpenter and Luis G.F. - New ACPI video blacklist entry for HP EliteBook Revolve 810 from Mika Westerberg" * tag 'pm+acpi-3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI / hotplug: Fix panic on eject to ejected device ACPI / battery: Fix incorrect sscanf() string in acpi_battery_init_alarm() ACPI / proc: remove unneeded NULL check ACPI / utils: remove a pointless NULL check ACPI / video: Add HP EliteBook Revolve 810 to the blacklist intel_pstate: Take core C0 time into account for core busy calculation ACPI / hotplug / PCI: Fix bridge removal race vs dock events ACPI / hotplug / PCI: Fix bridge removal race in handle_hotplug_event() ACPI / hotplug / PCI: Scan root bus under the PCI rescan-remove lock ACPI / hotplug / PCI: Move PCI rescan-remove locking to hotplug_event() ACPI / hotplug / PCI: Remove entries from bus->devices in reverse order
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由 Ilya Dryomov 提交于
Commit f38a5181 ("ceph: Convert to immutable biovecs") introduced a NULL pointer dereference, which broke rbd in -rc1. Fix it. Cc: Kent Overstreet <kmo@daterainc.com> Signed-off-by: NIlya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: NSage Weil <sage@inktank.com>
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由 H. Peter Anvin 提交于
* Avoid WARN_ON() when mapping BGRT on Baytrail (EFI 32-bit). Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
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由 Ilya Dryomov 提交于
Handling redirect replies requires both map_sem and request_mutex. Taking map_sem unconditionally near the top of handle_reply() avoids possible race conditions that arise from releasing request_mutex to be able to acquire map_sem in redirect reply case. (Lock ordering is: map_sem, request_mutex, crush_mutex.) Signed-off-by: NIlya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: NSage Weil <sage@inktank.com>
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由 Ilya Dryomov 提交于
Factor out logic from ceph_osdc_start_request() into a new helper, __ceph_osdc_start_request(). ceph_osdc_start_request() now amounts to taking locks and calling __ceph_osdc_start_request(). Signed-off-by: NIlya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: NSage Weil <sage@inktank.com>
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由 Mark Rutland 提交于
FPGA implementations of the Cortex-A57 and Cortex-A53 are now available in the form of the SMM-A57 and SMM-A53 Soft Macrocell Models (SMMs) for Versatile Express. As these attach to a Motherboard Express V2M-P1 it would be useful to have support for some V2M-P1 peripherals enabled by default. Additionally a couple of of features have been introduced since the last defconfig update (CMA, jump labels) that would be good to have enabled by default to ensure they are build and boot tested. This patch updates the arm64 defconfig to enable support for these devices and features. The arm64 Kconfig is modified to select HAVE_PATA_PLATFORM, which is required to enable support for the CompactFlash controller on the V2M-P1. A few options which don't need to appear in defconfig are trimmed: * BLK_DEV - selected by default * EXPERIMENTAL - otherwise gone from the kernel * MII - selected by drivers which require it * USB_SUPPORT - selected by default Signed-off-by: NMark Rutland <mark.rutland@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
cbnz/tbnz don't update the condition flags, so remove the "cc" clobbers from inline asm blocks that only use these instructions to implement conditional branches. Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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由 Will Deacon 提交于
Linux requires a number of atomic operations to provide full barrier semantics, that is no memory accesses after the operation can be observed before any accesses up to and including the operation in program order. On arm64, these operations have been incorrectly implemented as follows: // A, B, C are independent memory locations <Access [A]> // atomic_op (B) 1: ldaxr x0, [B] // Exclusive load with acquire <op(B)> stlxr w1, x0, [B] // Exclusive store with release cbnz w1, 1b <Access [C]> The assumption here being that two half barriers are equivalent to a full barrier, so the only permitted ordering would be A -> B -> C (where B is the atomic operation involving both a load and a store). Unfortunately, this is not the case by the letter of the architecture and, in fact, the accesses to A and C are permitted to pass their nearest half barrier resulting in orderings such as Bl -> A -> C -> Bs or Bl -> C -> A -> Bs (where Bl is the load-acquire on B and Bs is the store-release on B). This is a clear violation of the full barrier requirement. The simple way to fix this is to implement the same algorithm as ARMv7 using explicit barriers: <Access [A]> // atomic_op (B) dmb ish // Full barrier 1: ldxr x0, [B] // Exclusive load <op(B)> stxr w1, x0, [B] // Exclusive store cbnz w1, 1b dmb ish // Full barrier <Access [C]> but this has the undesirable effect of introducing *two* full barrier instructions. A better approach is actually the following, non-intuitive sequence: <Access [A]> // atomic_op (B) 1: ldxr x0, [B] // Exclusive load <op(B)> stlxr w1, x0, [B] // Exclusive store with release cbnz w1, 1b dmb ish // Full barrier <Access [C]> The simple observations here are: - The dmb ensures that no subsequent accesses (e.g. the access to C) can enter or pass the atomic sequence. - The dmb also ensures that no prior accesses (e.g. the access to A) can pass the atomic sequence. - Therefore, no prior access can pass a subsequent access, or vice-versa (i.e. A is strictly ordered before C). - The stlxr ensures that no prior access can pass the store component of the atomic operation. The only tricky part remaining is the ordering between the ldxr and the access to A, since the absence of the first dmb means that we're now permitting re-ordering between the ldxr and any prior accesses. From an (arbitrary) observer's point of view, there are two scenarios: 1. We have observed the ldxr. This means that if we perform a store to [B], the ldxr will still return older data. If we can observe the ldxr, then we can potentially observe the permitted re-ordering with the access to A, which is clearly an issue when compared to the dmb variant of the code. Thankfully, the exclusive monitor will save us here since it will be cleared as a result of the store and the ldxr will retry. Notice that any use of a later memory observation to imply observation of the ldxr will also imply observation of the access to A, since the stlxr/dmb ensure strict ordering. 2. We have not observed the ldxr. This means we can perform a store and influence the later ldxr. However, that doesn't actually tell us anything about the access to [A], so we've not lost anything here either when compared to the dmb variant. This patch implements this solution for our barriered atomic operations, ensuring that we satisfy the full barrier requirements where they are needed. Cc: <stable@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: NWill Deacon <will.deacon@arm.com> Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
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- 07 2月, 2014 9 次提交
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由 Adam Thomson 提交于
Remove use of regmap_irq_get_virq() in driver probe which was conflicting with use of platform_get_irq_byname(). platform_get_irq_byname() already returns the VIRQ number due to MFD core translation so using regmap_irq_get_virq() on that returned value results in an incorrect IRQ being requested. The driver probes then fail because of this. Signed-off-by: NAdam Thomson <Adam.Thomson.Opensource@diasemi.com> Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
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由 Rafael J. Wysocki 提交于
* acpi-cleanup: ACPI / battery: Fix incorrect sscanf() string in acpi_battery_init_alarm() ACPI / proc: remove unneeded NULL check ACPI / utils: remove a pointless NULL check * acpi-video: ACPI / video: Add HP EliteBook Revolve 810 to the blacklist
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由 Rafael J. Wysocki 提交于
* pm-cpufreq: intel_pstate: Take core C0 time into account for core busy calculation
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由 Rafael J. Wysocki 提交于
* acpi-pci-hotplug: ACPI / hotplug / PCI: Fix bridge removal race vs dock events ACPI / hotplug / PCI: Fix bridge removal race in handle_hotplug_event() ACPI / hotplug / PCI: Scan root bus under the PCI rescan-remove lock ACPI / hotplug / PCI: Move PCI rescan-remove locking to hotplug_event() ACPI / hotplug / PCI: Remove entries from bus->devices in reverse order * acpi-hotplug: ACPI / hotplug: Fix panic on eject to ejected device
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由 Linus Torvalds 提交于
Merge a bunch of fixes from Andrew Morton: "Commit 579f8290 ("swap: add a simple detector for inappropriate swapin readahead") is a feature. No probs if you decide to defer it until the next merge window. It has been sitting in my tree for over a year because of my dislike of all the magic numbers, but recent discussion with Hugh has made me give up" * emailed patches fron Andrew Morton <akpm@linux-foundation.org>: mm: __set_page_dirty uses spin_lock_irqsave instead of spin_lock_irq arch/x86/mm/numa.c: fix array index overflow when synchronizing nid to memblock.reserved. arch/x86/mm/numa.c: initialize numa_kernel_nodes in numa_clear_kernel_node_hotplug() mm: __set_page_dirty_nobuffers() uses spin_lock_irqsave() instead of spin_lock_irq() mm/swap: fix race on swap_info reuse between swapoff and swapon swap: add a simple detector for inappropriate swapin readahead ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters Documentation/kernel-parameters.txt: fix memmap= language
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由 KOSAKI Motohiro 提交于
To use spin_{un}lock_irq is dangerous if caller disabled interrupt. During aio buffer migration, we have a possibility to see the following call stack. aio_migratepage [disable interrupt] migrate_page_copy clear_page_dirty_for_io set_page_dirty __set_page_dirty_buffers __set_page_dirty spin_lock_irq This mean, current aio migration is a deadlockable. spin_lock_irqsave is a safer alternative and we should use it. Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reported-by: David Rientjes rientjes@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tang Chen 提交于
The following path will cause array out of bound. memblock_add_region() will always set nid in memblock.reserved to MAX_NUMNODES. In numa_register_memblks(), after we set all nid to correct valus in memblock.reserved, we called setup_node_data(), and used memblock_alloc_nid() to allocate memory, with nid set to MAX_NUMNODES. The nodemask_t type can be seen as a bit array. And the index is 0 ~ MAX_NUMNODES-1. After that, when we call node_set() in numa_clear_kernel_node_hotplug(), the nodemask_t got an index of value MAX_NUMNODES, which is out of [0 ~ MAX_NUMNODES-1]. See below: numa_init() |---> numa_register_memblks() | |---> memblock_set_node(memory) set correct nid in memblock.memory | |---> memblock_set_node(reserved) set correct nid in memblock.reserved | |...... | |---> setup_node_data() | |---> memblock_alloc_nid() here, nid is set to MAX_NUMNODES (1024) |...... |---> numa_clear_kernel_node_hotplug() |---> node_set() here, we have an index 1024, and overflowed This patch moves nid setting to numa_clear_kernel_node_hotplug() to fix this problem. Reported-by: NDave Jones <davej@redhat.com> Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com> Tested-by: NGu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: NDave Jones <davej@redhat.com> Cc: David Rientjes <rientjes@google.com> Tested-by: NDave Jones <davej@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tang Chen 提交于
On-stack variable numa_kernel_nodes in numa_clear_kernel_node_hotplug() was not initialized. So we need to initialize it. [akpm@linux-foundation.org: use NODE_MASK_NONE, per David] Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com> Tested-by: NGu Zheng <guz.fnst@cn.fujitsu.com> Reported-by: NDave Jones <davej@redhat.com> Reported-by: NDavid Rientjes <rientjes@google.com> Tested-by: NDave Jones <davej@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KOSAKI Motohiro 提交于
During aio stress test, we observed the following lockdep warning. This mean AIO+numa_balancing is currently deadlockable. The problem is, aio_migratepage disable interrupt, but __set_page_dirty_nobuffers unintentionally enable it again. Generally, all helper function should use spin_lock_irqsave() instead of spin_lock_irq() because they don't know caller at all. other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&ctx->completion_lock)->rlock); <Interrupt> lock(&(&ctx->completion_lock)->rlock); *** DEADLOCK *** dump_stack+0x19/0x1b print_usage_bug+0x1f7/0x208 mark_lock+0x21d/0x2a0 mark_held_locks+0xb9/0x140 trace_hardirqs_on_caller+0x105/0x1d0 trace_hardirqs_on+0xd/0x10 _raw_spin_unlock_irq+0x2c/0x50 __set_page_dirty_nobuffers+0x8c/0xf0 migrate_page_copy+0x434/0x540 aio_migratepage+0xb1/0x140 move_to_new_page+0x7d/0x230 migrate_pages+0x5e5/0x700 migrate_misplaced_page+0xbc/0xf0 do_numa_page+0x102/0x190 handle_pte_fault+0x241/0x970 handle_mm_fault+0x265/0x370 __do_page_fault+0x172/0x5a0 do_page_fault+0x1a/0x70 page_fault+0x28/0x30 Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <jweiner@redhat.com> Acked-by: NDavid Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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