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2013-09-03Merge tag 'pm+acpi-3.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: 1) ACPI-based PCI hotplug (ACPIPHP) subsystem rework and introduction of Intel Thunderbolt support on systems that use ACPI for signalling Thunderbolt hotplug events. This also should make ACPIPHP work in some cases in which it was known to have problems. From Rafael J Wysocki, Mika Westerberg and Kirill A Shutemov. 2) ACPI core code cleanups and dock station support cleanups from Jiang Liu and Rafael J Wysocki. 3) Fixes for locking problems related to ACPI device hotplug from Rafael J Wysocki. 4) ACPICA update to version 20130725 includig fixes, cleanups, support for more than 256 GPEs per GPE block and a change to make the ACPI PM Timer optional (we've seen systems without the PM Timer in the field already). One of the fixes, related to the DeRefOf operator, is necessary to prevent some Windows 8 oriented AML from causing problems to happen. From Bob Moore, Lv Zheng, and Jung-uk Kim. 5) Removal of the old and long deprecated /proc/acpi/event interface and related driver changes from Thomas Renninger. 6) ACPI and Xen changes to make the reduced hardware sleep work with the latter from Ben Guthro. 7) ACPI video driver cleanups and a blacklist of systems that should not tell the BIOS that they are compatible with Windows 8 (or ACPI backlight and possibly other things will not work on them). From Felipe Contreras. 8) Assorted ACPI fixes and cleanups from Aaron Lu, Hanjun Guo, Kuppuswamy Sathyanarayanan, Lan Tianyu, Sachin Kamat, Tang Chen, Toshi Kani, and Wei Yongjun. 9) cpufreq ondemand governor target frequency selection change to reduce oscillations between min and max frequencies (essentially, it causes the governor to choose target frequencies proportional to load) from Stratos Karafotis. 10) cpufreq fixes allowing sysfs attributes file permissions to be preserved over suspend/resume cycles Srivatsa S Bhat. 11) Removal of Device Tree parsing for CPU device nodes from multiple cpufreq drivers that required some changes related to of_get_cpu_node() to be made in a few architectures and in the driver core. From Sudeep KarkadaNagesha. 12) cpufreq core fixes and cleanups related to mutual exclusion and driver module references from Viresh Kumar, Lukasz Majewski and Rafael J Wysocki. 13) Assorted cpufreq fixes and cleanups from Amit Daniel Kachhap, Bartlomiej Zolnierkiewicz, Hanjun Guo, Jingoo Han, Joseph Lo, Julia Lawall, Li Zhong, Mark Brown, Sascha Hauer, Stephen Boyd, Stratos Karafotis, and Viresh Kumar. 14) Fixes to prevent race conditions in coupled cpuidle from happening from Colin Cross. 15) cpuidle core fixes and cleanups from Daniel Lezcano and Tuukka Tikkanen. 16) Assorted cpuidle fixes and cleanups from Daniel Lezcano, Geert Uytterhoeven, Jingoo Han, Julia Lawall, Linus Walleij, and Sahara. 17) System sleep tracing changes from Todd E Brandt and Shuah Khan. 18) PNP subsystem conversion to using struct dev_pm_ops for power management from Shuah Khan. * tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (217 commits) cpufreq: Don't use smp_processor_id() in preemptible context cpuidle: coupled: fix race condition between pokes and safe state cpuidle: coupled: abort idle if pokes are pending cpuidle: coupled: disable interrupts after entering safe state ACPI / hotplug: Remove containers synchronously driver core / ACPI: Avoid device hot remove locking issues cpufreq: governor: Fix typos in comments cpufreq: governors: Remove duplicate check of target freq in supported range cpufreq: Fix timer/workqueue corruption due to double queueing ACPI / EC: Add ASUSTEK L4R to quirk list in order to validate ECDT ACPI / thermal: Add check of "_TZD" availability and evaluating result cpufreq: imx6q: Fix clock enable balance ACPI: blacklist win8 OSI for buggy laptops cpufreq: tegra: fix the wrong clock name cpuidle: Change struct menu_device field types cpuidle: Add a comment warning about possible overflow cpuidle: Fix variable domains in get_typical_interval() cpuidle: Fix menu_device->intervals type cpuidle: CodingStyle: Break up multiple assignments on single line cpuidle: Check called function parameter in get_typical_interval() ...
2013-09-03Merge tag 'driver-core-3.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches from Greg KH: "Here's the big driver core pull request for 3.12-rc1. Lots of tiny changes here fixing up the way sysfs attributes are created, to try to make drivers simpler, and fix a whole class race conditions with creations of device attributes after the device was announced to userspace. All the various pieces are acked by the different subsystem maintainers" * tag 'driver-core-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (119 commits) firmware loader: fix pending_fw_head list corruption drivers/base/memory.c: introduce help macro to_memory_block dynamic debug: line queries failing due to uninitialized local variable sysfs: sysfs_create_groups returns a value. debugfs: provide debugfs_create_x64() when disabled rbd: convert bus code to use bus_groups firmware: dcdbas: use binary attribute groups sysfs: add sysfs_create/remove_groups for when SYSFS is not enabled driver core: add #include <linux/sysfs.h> to core files. HID: convert bus code to use dev_groups Input: serio: convert bus code to use drv_groups Input: gameport: convert bus code to use drv_groups driver core: firmware: use __ATTR_RW() driver core: core: use DEVICE_ATTR_RO driver core: bus: use DRIVER_ATTR_WO() driver core: create write-only attribute macros for devices and drivers sysfs: create __ATTR_WO() driver-core: platform: convert bus code to use dev_groups workqueue: convert bus code to use dev_groups MEI: convert bus code to use dev_groups ...
2013-09-03x86: add early quirk for reserving Intel graphics stolen memory v5Jesse Barnes
Systems with Intel graphics controllers set aside memory exclusively for gfx driver use. This memory is not always marked in the E820 as reserved or as RAM, and so is subject to overlap from E820 manipulation later in the boot process. On some systems, MMIO space is allocated on top, despite the efforts of the "RAM buffer" approach, which simply rounds memory boundaries up to 64M to try to catch space that may decode as RAM and so is not suitable for MMIO. v2: use read_pci_config for 32 bit reads instead of adding a new one (Chris) add gen6 stolen size function (Chris) v3: use a function pointer (Chris) drop gen2 bits (Daniel) v4: call e820_sanitize_map after adding the region v5: fixup comments (Peter) simplify loop (Chris) Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66726 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66844 Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-03Merge branch 'lockref' (locked reference counts)Linus Torvalds
Merge lockref infrastructure code by me and Waiman Long. I already merged some of the preparatory patches that didn't actually do any semantic changes earlier, but this merges the actual _reason_ for those preparatory patches. The "lockref" structure is a combination "spinlock and reference count" that allows optimized reference count accesses. In particular, it guarantees that the reference count will be updated AS IF the spinlock was held, but using atomic accesses that cover both the reference count and the spinlock words, we can often do the update without actually having to take the lock. This allows us to avoid the nastiest cases of spinlock contention on large machines under heavy pathname lookup loads. When updating the dentry reference counts on a large system, we'll still end up with the cache line bouncing around, but that's much less noticeable than actually having to spin waiting for the lock. * lockref: lockref: implement lockless reference count updates using cmpxchg() lockref: uninline lockref helper functions vfs: reimplement d_rcu_to_refcount() using lockref_get_or_lock() vfs: use lockref_get_not_zero() for optimistic lockless dget_parent() lockref: add 'lockref_get_or_lock() helper
2013-09-02lockref: implement lockless reference count updates using cmpxchg()Linus Torvalds
Instead of taking the spinlock, the lockless versions atomically check that the lock is not taken, and do the reference count update using a cmpxchg() loop. This is semantically identical to doing the reference count update protected by the lock, but avoids the "wait for lock" contention that you get when accesses to the reference count are contended. Note that a "lockref" is absolutely _not_ equivalent to an atomic_t. Even when the lockref reference counts are updated atomically with cmpxchg, the fact that they also verify the state of the spinlock means that the lockless updates can never happen while somebody else holds the spinlock. So while "lockref_put_or_lock()" looks a lot like just another name for "atomic_dec_and_lock()", and both optimize to lockless updates, they are fundamentally different: the decrement done by atomic_dec_and_lock() is truly independent of any lock (as long as it doesn't decrement to zero), so a locked region can still see the count change. The lockref structure, in contrast, really is a *locked* reference count. If you hold the spinlock, the reference count will be stable and you can modify the reference count without using atomics, because even the lockless updates will see and respect the state of the lock. In order to enable the cmpxchg lockless code, the architecture needs to do three things: (1) Make sure that the "arch_spinlock_t" and an "unsigned int" can fit in an aligned u64, and have a "cmpxchg()" implementation that works on such a u64 data type. (2) define a helper function to test for a spinlock being unlocked ("arch_spin_value_unlocked()") (3) select the "ARCH_USE_CMPXCHG_LOCKREF" config variable in its Kconfig file. This enables it for x86-64 (but not 32-bit, we'd need to make sure cmpxchg() turns into the proper cmpxchg8b in order to enable it for 32-bit mode). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-02Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot fix from Peter Anvin: "A single very small boot fix for very large memory systems (> 0.5T)" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Fix boot crash with DEBUG_PAGE_ALLOC=y and more than 512G RAM
2013-09-02perf: Convert kmalloc_node(...GFP_ZERO...) to kzalloc_node()Joe Perches
Use the convenience function instead of __GFP_ZERO. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/f58599ae1a8d7b32d37e9cf283e95fba6452f7f6.1377809875.git.joe@perches.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-02perf/x86: Add Silvermont (22nm Atom) supportYan, Zheng
Compared to old atom, Silvermont has offcore and has more events that support PEBS. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1374138144-17278-2-git-send-email-zheng.z.yan@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-02perf/x86: use INTEL_UEVENT_EXTRA_REG to define MSR_OFFCORE_RSP_XYan, Zheng
Silvermont (22nm Atom) has two offcore response configuration MSRs, unlike other Intel CPU, its event code for MSR_OFFCORE_RSP_1 is 0x02b7. To avoid complicating intel_fixup_er(), use INTEL_UEVENT_EXTRA_REG to define MSR_OFFCORE_RSP_X. So intel_fixup_er() can find the event code for OFFCORE_RSP_N by x86_pmu.extra_regs[N].event. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1374138144-17278-1-git-send-email-zheng.z.yan@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-01Introduce [compat_]save_altstack_ex() to unbreak x86 SMAPAl Viro
For performance reasons, when SMAP is in use, SMAP is left open for an entire put_user_try { ... } put_user_catch(); block, however, calling __put_user() in the middle of that block will close SMAP as the STAC..CLAC constructs intentionally do not nest. Furthermore, using __put_user() rather than put_user_ex() here is bad for performance. Thus, introduce new [compat_]save_altstack_ex() helpers that replace __[compat_]save_altstack() for x86, being currently the only architecture which supports put_user_try { ... } put_user_catch(). Reported-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.8+ Link: http://lkml.kernel.org/n/tip-es5p6y64if71k8p5u08agv9n@git.kernel.org
2013-09-01x86, smap: Handle csum_partial_copy_*_user()H. Peter Anvin
Add SMAP annotations to csum_partial_copy_to/from_user(). These functions legitimately access user space and thus need to set the AC flag. TODO: add explicit checks that the side with the kernel space pointer really points into kernel space. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/n/tip-2aps0u00eer658fd5xyanan7@git.kernel.org Cc: <stable@vger.kernel.org> # v3.7+
2013-08-29x86, doc: Update uaccess.h comment to reflect clang changesH. Peter Anvin
Update comment in uaccess.h to reflect the changes for clang support: gcc only cares about the base register (most architectures don't encode the size of the operation in the operands like x86 does, and so it is treated effectively like a register number), whereas clang tries to enforce the size -- but not for register pairs. Link: http://lkml.kernel.org/r/1377803585-5913-3-git-send-email-dl9pf@gmx.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jan-Simon Möller <dl9pf@gmx.de>
2013-08-29x86, asm: Fix a compilation issue with clangJan-Simon Möller
Clang does not support the "shortcut" we're taking here for gcc (see below). The patch uses the macro _ASM_DX to do the job. From arch/x86/include/asm/uaccess.h: /* * Careful: we have to cast the result to the type of the pointer * for sign reasons. * * The use of %edx as the register specifier is a bit of a * simplification, as gcc only cares about it as the starting point * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits * (%ecx being the next register in gcc's x86 register sequence), and * %rdx on 64 bits. */ [ hpa: I consider this a compatibility bug in clang as this reflects a bit of a misunderstanding about how register strings are used by gcc, but the workaround is straightforward and there is no particular reason to not do it. ] Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> Link: http://lkml.kernel.org/r/1377803585-5913-3-git-send-email-dl9pf@gmx.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-29x86, asm: Extend definitions of _ASM_* with a raw formatJan-Simon Möller
The __ASM_* macros (e.g. __ASM_DX) are used to return the proper register name (e.g. edx for 32bit / rdx for 64bit). We want to use this also in arch/x86/include/asm/uaccess.h / get_user() . For this to work, we need a raw form as both gcc and clang choke on the whitespace in a register asm() statement, and the __ASM_FORM macro surrounds the argument with blanks. A new macro, __ASM_FORM_RAW was added and we change __ASM_REG to use the new RAW form. Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> Link: http://lkml.kernel.org/r/1377803585-5913-2-git-send-email-dl9pf@gmx.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-29gpio: (gpio-pca953x) move header to linux/platform_data/Vivien Didelot
This patch moves the pca953x.h header from include/linux/i2c to include/linux/platform_data and updates existing support accordingly. Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-29Merge branch 'linus' into perf/coreIngo Molnar
Pick up the latest upstream fixes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-29KVM: MMU: remove unused parameterXiao Guangrong
vcpu in page_fault_can_be_fast() is not used so remove it Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-28Merge tag 'v3.11-rc7' into devicetree/nextGrant Likely
Linux 3.11-rc7
2013-08-28KVM: x86: update masterclock when kvmclock_offset is calculated (v2)Marcelo Tosatti
The offset to add to the hosts monotonic time, kvmclock_offset, is calculated against the monotonic time at KVM_SET_CLOCK ioctl time. Request a master clock update at this time, to reduce a potentially unbounded difference between the values of the masterclock and the clock value used to calculate kvmclock_offset. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-28KVM: x86: add comments where MMIO does not return to the emulatorPaolo Bonzini
Support for single-step in the emulator (new in 3.12) does not work for MMIO or PIO writes, because they are completed without returning to the emulator. This is not worse than what we had in 3.11; still, add comments so that the issue is not forgotten. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-28KVM: vmx: count exits to userspace during invalid guest emulationPaolo Bonzini
These will happen due to MMIO. Suggested-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-27drivers: dma-contiguous: clean source code and prepare for device treeMarek Szyprowski
This patch cleans the initialization of dma contiguous framework. The all-in-one dma_declare_contiguous() function is now separated into dma_contiguous_reserve_area() which only steals the the memory from memblock allocator and dma_contiguous_add_device() function, which assigns given device to the specified reserved memory area. This improves the flexibility in defining contiguous memory areas and assigning device to them, because now it is possible to assign more than one device to the given contiguous memory area. Such split in initialization procedure is also required for upcoming device tree support. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Tomasz Figa <t.figa@samsung.com>
2013-08-27Merge branch 'pm-cpufreq'Rafael J. Wysocki
* pm-cpufreq: (60 commits) cpufreq: pmac32-cpufreq: remove device tree parsing for cpu nodes cpufreq: pmac64-cpufreq: remove device tree parsing for cpu nodes cpufreq: maple-cpufreq: remove device tree parsing for cpu nodes cpufreq: arm_big_little: remove device tree parsing for cpu nodes cpufreq: kirkwood-cpufreq: remove device tree parsing for cpu nodes cpufreq: spear-cpufreq: remove device tree parsing for cpu nodes cpufreq: highbank-cpufreq: remove device tree parsing for cpu nodes cpufreq: cpufreq-cpu0: remove device tree parsing for cpu nodes cpufreq: imx6q-cpufreq: remove device tree parsing for cpu nodes drivers/bus: arm-cci: avoid parsing DT for cpu device nodes ARM: mvebu: remove device tree parsing for cpu nodes ARM: topology: remove hwid/MPIDR dependency from cpu_capacity of/device: add helper to get cpu device node from logical cpu index driver/core: cpu: initialize of_node in cpu's device struture ARM: DT/kernel: define ARM specific arch_match_cpu_phys_id of: move of_get_cpu_node implementation to DT core library powerpc: refactor of_get_cpu_node to support other architectures openrisc: remove undefined of_get_cpu_node declaration microblaze: remove undefined of_get_cpu_node declaration cpufreq: fix bad unlock balance on !CONFIG_SMP ...
2013-08-27Merge branch 'acpi-assorted'Rafael J. Wysocki
* acpi-assorted: ACPI / osl: Kill macro INVALID_TABLE(). earlycpio.c: Fix the confusing comment of find_cpio_data(). ACPI / x86: Print Hot-Pluggable Field in SRAT. ACPI / thermal: Use THERMAL_TRIPS_NONE macro to replace number ACPI / thermal: Remove unused macros in the driver/acpi/thermal.c ACPI / thermal: Remove the unused lock of struct acpi_thermal ACPI / osl: Fix osi_setup_entries[] __initdata attribute location ACPI / numa: Fix __init attribute location in slit_valid() ACPI / dock: Fix __init attribute location in find_dock_and_bay() ACPI / Sleep: Fix incorrect placement of __initdata ACPI / processor: Fix incorrect placement of __initdata ACPI / EC: Fix incorrect placement of __initdata ACPI / scan: Drop unnecessary label from acpi_create_platform_device() ACPI: Move acpi_bus_get_device() from bus.c to scan.c ACPI / scan: Allow platform device creation without any IO resources ACPI: Cleanup sparse warning on acpi_os_initialize1() platform / thinkpad: Remove deprecated hotkey_report_mode parameter ACPI: Remove the old /proc/acpi/event interface
2013-08-27Merge branch 'acpi-sleep'Rafael J. Wysocki
* acpi-sleep: x86 / tboot / ACPI: Fail extended mode reduced hardware sleep xen / ACPI: notify xen when reduced hardware sleep is available ACPI / sleep: Introduce acpi_os_prepare_extended_sleep() for extended sleep path
2013-08-27Merge branch 'acpi-pci-hotplug'Rafael J. Wysocki
* acpi-pci-hotplug: (34 commits) ACPI / PM: Hold acpi_scan_lock over system PM transitions ACPI / hotplug / PCI: Fix NULL pointer dereference in cleanup_bridge() PCI / ACPI: Use dev_dbg() instead of dev_info() in acpi_pci_set_power_state() ACPI / hotplug / PCI: Get rid of check_sub_bridges() ACPI / hotplug / PCI: Clean up bridge_mutex usage ACPI / hotplug / PCI: Redefine enable_device() and disable_device() ACPI / hotplug / PCI: Sanitize acpiphp_get_(latch)|(adapter)_status() ACPI / hotplug / PCI: Get rid of unused constants in acpiphp.h ACPI / hotplug / PCI: Check for new devices on enabled slots ACPI / hotplug / PCI: Allow slots without new devices to be rescanned ACPI / hotplug / PCI: Do not check SLOT_ENABLED in enable_device() ACPI / hotplug / PCI: Do not exectute _PS0 and _PS3 directly ACPI / hotplug / PCI: Do not queue up event handling work items in vain ACPI / hotplug / PCI: Consolidate slot disabling and ejecting ACPI / hotplug / PCI: Drop redundant checks from check_hotplug_bridge() ACPI / hotplug / PCI: Rework namespace scanning and trimming routines ACPI / hotplug / PCI: Store parent in functions and bus in slots ACPI / hotplug / PCI: Drop handle field from struct acpiphp_bridge ACPI / hotplug / PCI: Drop handle field from struct acpiphp_func ACPI / hotplug / PCI: Embed function struct into struct acpiphp_context ...
2013-08-26Merge branch 'pci/yijing-mps-v8' into nextBjorn Helgaas
* pci/yijing-mps-v8: PCI: Warn if unsafe MPS settings detected PCI: Fix MPS peer-to-peer DMA comment syntax PCI: Don't restrict MPS for slots below Root Ports PCI: Simplify MPS test for Downstream Port PCI: Remove unnecessary check for pcie_get_mps() failure PCI: Simplify pcie_bus_configure_settings() interface PCI: Drop "PCI-E" prefix from Max Payload Size message
2013-08-26x86/ioapic: Check attr against the previous setting when programmed more ↵Liu Ping Fan
than once When programming ioapic pinX more than once, current code does not check whether the later attr (trigger & polarity) is the same as the former or not. This causes broken semantics which can be observed in a qemu q35 machine, where ioapic's ioredtbl[x] can never be set as low-active, even if the hpet driver registered it. And hpet driver may share a high-level active IRQ line with other devices. So in qemu, when hpet-dev asserts low-level as kernel expects, the kernel has no response. With this patch, we can observe an ioredtbl[x] set as low-active for hpet. Fix it by reporting -EBUSY to the caller, when attr is different. Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com> Cc: Kevin Hao <haokexin@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1377248327-19633-1-git-send-email-pingfank@linux.vnet.ibm.com [ Made small readability edits to both the changelog and the code. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-26kvm hypervisor: Simplify kvm_for_each_vcpu with kvm_irq_delivery_to_apicRaghavendra K T
Note that we are using APIC_DM_REMRD which has reserved usage. In future if APIC_DM_REMRD usage is standardized, then we should find some other way or go back to old method. Suggested-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Acked-by: Gleb Natapov <gleb@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-26kvm hypervisor : Add a hypercall to KVM hypervisor to support pv-ticketlocksSrivatsa Vaddagiri
kvm_hc_kick_cpu allows the calling vcpu to kick another vcpu out of halt state. the presence of these hypercalls is indicated to guest via kvm_feature_pv_unhalt. Fold pv_unhalt flag into GET_MP_STATE ioctl to aid migration During migration, any vcpu that got kicked but did not become runnable (still in halted state) should be runnable after migration. Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com> [Raghu: Apic related changes, folding pvunhalted into vcpu_runnable Added flags for future use (suggested by Gleb)] [ Raghu: fold pv_unhalt flag as suggested by Eric Northup] Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Acked-by: Gleb Natapov <gleb@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-26kvm uapi: Add KICK_CPU and PV_UNHALT definition to uapiRaghavendra K T
this is needed by both guest and host. Originally-from: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Acked-by: Gleb Natapov <gleb@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-23Merge back earlier 'pm-cpufreq' material.Rafael J. Wysocki
2013-08-22Kconfig: Remove hotplug enable hints in CONFIG_KEXEC help textsGeert Uytterhoeven
commit 40b313608ad4ea655addd2ec6cdd106477ae8e15 ("Finally eradicate CONFIG_HOTPLUG") removed remaining references to CONFIG_HOTPLUG, but missed a few plain English references in the CONFIG_KEXEC help texts. Remove them, too. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22x86 get_unmapped_area: Access mmap_legacy_base through mm_struct memberRadu Caragea
This is the updated version of df54d6fa5427 ("x86 get_unmapped_area(): use proper mmap base for bottom-up direction") that only randomizes the mmap base address once. Signed-off-by: Radu Caragea <sinaelgl@gmail.com> Reported-and-tested-by: Jeff Shorey <shoreyjeff@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michel Lespinasse <walken@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Adrian Sendroiu <molecula2788@gmail.com> Cc: Greg KH <greg@kroah.com> Cc: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-22Revert "x86 get_unmapped_area(): use proper mmap base for bottom-up direction"Linus Torvalds
This reverts commit df54d6fa54275ce59660453e29d1228c2b45a826. The commit isn't necessarily wrong, but because it recalculates the random mmap_base every time, it seems to confuse user memory allocators that expect contiguous mmap allocations even when the mmap address isn't specified. In particular, the MATLAB Java runtime seems to be unhappy. See https://bugzilla.kernel.org/show_bug.cgi?id=60774 So we'll want to apply the random offset only once, and Radu has a patch for that. Revert this older commit in order to apply the other one. Reported-by: Jeff Shorey <shoreyjeff@gmail.com> Cc: Radu Caragea <sinaelgl@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-22PCI: Simplify pcie_bus_configure_settings() interfaceBjorn Helgaas
Based on a patch by Jon Mason (see URL below). All users of pcie_bus_configure_settings() pass arguments of the form "bus, bus->self->pcie_mpss". The "mpss" argument is redundant since we can easily look it up internally. In addition, all callers check "bus->self" for NULL, which we can also do internally. This patch simplifies the interface and the callers. No functional change. Reference: http://lkml.kernel.org/r/1317048850-30728-2-git-send-email-mason@myri.com Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-08-22x86/asmlinkage: Fix warning in xen asmlinkage changeAndi Kleen
Current code uses asmlinkage for functions without arguments. This adds an implicit regparm(0) which creates a warning when assigning the function to pointers. Use __visible for the functions without arguments. This avoids having to add regparm(0) to function pointers. Since they have no arguments it does not make any difference. Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1377115662-4865-1-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-21Merge tag 'stable/for-linus-3.11-rc6-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull Xen bug-fixes from Konrad Rzeszutek Wilk: - On ARM did not have balanced calls to get/put_cpu. - Fix to make tboot + Xen + Linux correctly. - Fix events VCPU binding issues. - Fix a vCPU online race where IPIs are sent to not-yet-online vCPU. * tag 'stable/for-linus-3.11-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/smp: initialize IPI vectors before marking CPU online xen/events: mask events when changing their VCPU binding xen/events: initialize local per-cpu mask for all possible events x86/xen: do not identity map UNUSABLE regions in the machine E820 xen/arm: missing put_cpu in xen_percpu_init
2013-08-21Merge tag 'tegra-for-3.12-soc' of ↵Kevin Hilman
git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/soc From: Stephen Warren: ARM: tegra: core SoC enhancements for 3.12 This branch includes a number of enhancements to core SoC support for Tegra devices. The major new features are: * Adds a new CPU-power-gated cpuidle state for Tegra114. * Adds initial system suspend support for Tegra114, initially supporting just CPU-power-gating during suspend. * Adds "LP1" suspend mode support for all of Tegra20/30/114. This mode both gates CPU power, and places the DRAM into self-refresh mode. * A new DT-driven PCIe driver to Tegra20/30. The driver is also moved from arch/arm/mach-tegra/ to drivers/pci/host/. The PCIe driver work depends on the following tag from Thomas Petazzoni: git://git.infradead.org/linux-mvebu.git mis-3.12.2 ... which is merged into the middle of this pull request. * tag 'tegra-for-3.12-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: (33 commits) ARM: tegra: disable LP2 cpuidle state if PCIe is enabled MAINTAINERS: Add myself as Tegra PCIe maintainer PCI: tegra: set up PADS_REFCLK_CFG1 PCI: tegra: Add Tegra 30 PCIe support PCI: tegra: Move PCIe driver to drivers/pci/host PCI: msi: add default MSI operations for !HAVE_GENERIC_HARDIRQS platforms ARM: tegra: add LP1 suspend support for Tegra114 ARM: tegra: add LP1 suspend support for Tegra20 ARM: tegra: add LP1 suspend support for Tegra30 ARM: tegra: add common LP1 suspend support clk: tegra114: add LP1 suspend/resume support ARM: tegra: config the polarity of the request of sys clock ARM: tegra: add common resume handling code for LP1 resuming ARM: pci: add ->add_bus() and ->remove_bus() hooks to hw_pci of: pci: add registry of MSI chips PCI: Introduce new MSI chip infrastructure PCI: remove ARCH_SUPPORTS_MSI kconfig option PCI: use weak functions for MSI arch-specific functions ARM: tegra: unify Tegra's Kconfig a bit more ARM: tegra: remove the limitation that Tegra114 can't support suspend ... Signed-off-by: Kevin Hilman <khilman@linaro.org>
2013-08-21crypto: xor - Check for osxsave as well as avx in crypto/xorJohn Haxby
This affects xen pv guests with sufficiently old versions of xen and sufficiently new hardware. On such a system, a guest with a btrfs root won't even boot. Signed-off-by: John Haxby <john.haxby@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-08-21crypto: camellia-x86-64 - replace commas by semicolons and adjust code alignmentJulia Lawall
Adjust alignment and replace commas by semicolons in automatically generated code. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-08-20xen/pvhvm: Initialize xen panic handler for PVHVM guestsVaughan Cao
kernel use callback linked in panic_notifier_list to notice others when panic happens. NORET_TYPE void panic(const char * fmt, ...){ ... atomic_notifier_call_chain(&panic_notifier_list, 0, buf); } When Xen becomes aware of this, it will call xen_reboot(SHUTDOWN_crash) to send out an event with reason code - SHUTDOWN_crash. xen_panic_handler_init() is defined to register on panic_notifier_list but we only call it in xen_arch_setup which only be called by PV, this patch is necessary for PVHVM. Without this patch, setting 'on_crash=coredump-restart' in PVHVM guest config file won't lead a vmcore to be generate when the guest panics. It can be reproduced with 'echo c > /proc/sysrq-trigger'. Signed-off-by: Vaughan Cao <vaughan.cao@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Joe Jin <joe.jin@oracle.com>
2013-08-20xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mappingStefano Stabellini
GNTTABOP_unmap_grant_ref unmaps a grant and replaces it with a 0 mapping instead of reinstating the original mapping. Doing so separately would be racy. To unmap a grant and reinstate the original mapping atomically we use GNTTABOP_unmap_and_replace. GNTTABOP_unmap_and_replace doesn't work with GNTMAP_contains_pte, so don't use it for kmaps. GNTTABOP_unmap_and_replace zeroes the mapping passed in new_addr so we have to reinstate it, however that is a per-cpu mapping only used for balloon scratch pages, so we can be sure that it's not going to be accessed while the mapping is not valid. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: alex@alex.org.uk CC: dcrisan@flexiant.com [v1: Konrad fixed up the conflicts] Conflicts: arch/x86/xen/p2m.c
2013-08-20xen/smp: initialize IPI vectors before marking CPU onlineChuck Anderson
An older PVHVM guest (v3.0 based) crashed during vCPU hot-plug with: kernel BUG at drivers/xen/events.c:1328! RCU has detected that a CPU has not entered a quiescent state within the grace period. It needs to send the CPU a reschedule IPI if it is not offline. rcu_implicit_offline_qs() does this check: /* * If the CPU is offline, it is in a quiescent state. We can * trust its state not to change because interrupts are disabled. */ if (cpu_is_offline(rdp->cpu)) { rdp->offline_fqs++; return 1; } Else the CPU is online. Send it a reschedule IPI. The CPU is in the middle of being hot-plugged and has been marked online (!cpu_is_offline()). See start_secondary(): set_cpu_online(smp_processor_id(), true); ... per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE; start_secondary() then waits for the CPU bringing up the hot-plugged CPU to mark it as active: /* * Wait until the cpu which brought this one up marked it * online before enabling interrupts. If we don't do that then * we can end up waking up the softirq thread before this cpu * reached the active state, which makes the scheduler unhappy * and schedule the softirq thread on the wrong cpu. This is * only observable with forced threaded interrupts, but in * theory it could also happen w/o them. It's just way harder * to achieve. */ while (!cpumask_test_cpu(smp_processor_id(), cpu_active_mask)) cpu_relax(); /* enable local interrupts */ local_irq_enable(); The CPU being hot-plugged will be marked active after it has been fully initialized by the CPU managing the hot-plug. In the Xen PVHVM case xen_smp_intr_init() is called to set up the hot-plugged vCPU's XEN_RESCHEDULE_VECTOR. The hot-plugging CPU is marked online, not marked active and does not have its IPI vectors set up. rcu_implicit_offline_qs() sees the hot-plugging cpu is !cpu_is_offline() and tries to send it a reschedule IPI: This will lead to: kernel BUG at drivers/xen/events.c:1328! xen_send_IPI_one() xen_smp_send_reschedule() rcu_implicit_offline_qs() rcu_implicit_dynticks_qs() force_qs_rnp() force_quiescent_state() __rcu_process_callbacks() rcu_process_callbacks() __do_softirq() call_softirq() do_softirq() irq_exit() xen_evtchn_do_upcall() because xen_send_IPI_one() will attempt to use an uninitialized IRQ for the XEN_RESCHEDULE_VECTOR. There is at least one other place that has caused the same crash: xen_smp_send_reschedule() wake_up_idle_cpu() add_timer_on() clocksource_watchdog() call_timer_fn() run_timer_softirq() __do_softirq() call_softirq() do_softirq() irq_exit() xen_evtchn_do_upcall() xen_hvm_callback_vector() clocksource_watchdog() uses cpu_online_mask to pick the next CPU to handle a watchdog timer: /* * Cycle through CPUs to check if the CPUs stay synchronized * to each other. */ next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask); if (next_cpu >= nr_cpu_ids) next_cpu = cpumask_first(cpu_online_mask); watchdog_timer.expires += WATCHDOG_INTERVAL; add_timer_on(&watchdog_timer, next_cpu); This resulted in an attempt to send an IPI to a hot-plugging CPU that had not initialized its reschedule vector. One option would be to make the RCU code check to not check for CPU offline but for CPU active. As becoming active is done after a CPU is online (in older kernels). But Srivatsa pointed out that "the cpu_active vs cpu_online ordering has been completely reworked - in the online path, cpu_active is set *before* cpu_online, and also, in the cpu offline path, the cpu_active bit is reset in the CPU_DYING notification instead of CPU_DOWN_PREPARE." Drilling in this the bring-up path: "[brought up CPU].. send out a CPU_STARTING notification, and in response to that, the scheduler sets the CPU in the cpu_active_mask. Again, this mask is better left to the scheduler alone, since it has the intelligence to use it judiciously." The conclusion was that: " 1. At the IPI sender side: It is incorrect to send an IPI to an offline CPU (cpu not present in the cpu_online_mask). There are numerous places where we check this and warn/complain. 2. At the IPI receiver side: It is incorrect to let the world know of our presence (by setting ourselves in global bitmasks) until our initialization steps are complete to such an extent that we can handle the consequences (such as receiving interrupts without crashing the sender etc.) " (from Srivatsa) As the native code enables the interrupts at some point we need to be able to service them. In other words a CPU must have valid IPI vectors if it has been marked online. It doesn't need to handle the IPI (interrupts may be disabled) but needs to have valid IPI vectors because another CPU may find it in cpu_online_mask and attempt to send it an IPI. This patch will change the order of the Xen vCPU bring-up functions so that Xen vectors have been set up before start_secondary() is called. It also will not continue to bring up a Xen vCPU if xen_smp_intr_init() fails to initialize it. Orabug 13823853 Signed-off-by Chuck Anderson <chuck.anderson@oracle.com> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-08-20x86/xen: during early setup, only 1:1 map the ISA regionDavid Vrabel
During early setup, when the reserved regions and MMIO holes are being setup as 1:1 in the p2m, clear any mappings instead of making them 1:1 (execept for the ISA region which is expected to be mapped). This fixes a regression introduced in 3.5 by 83d51ab473dd (xen/setup: update VA mapping when releasing memory during setup) which caused hosts with tboot to fail to boot. tboot marks a region in the e820 map as unusable and the dom0 kernel would attempt to map this region and Xen does not permit unusable regions to be mapped by guests. (XEN) 0000000000000000 - 0000000000060000 (usable) (XEN) 0000000000060000 - 0000000000068000 (reserved) (XEN) 0000000000068000 - 000000000009e000 (usable) (XEN) 0000000000100000 - 0000000000800000 (usable) (XEN) 0000000000800000 - 0000000000972000 (unusable) tboot marked this region as unusable. (XEN) 0000000000972000 - 00000000cf200000 (usable) (XEN) 00000000cf200000 - 00000000cf38f000 (reserved) (XEN) 00000000cf38f000 - 00000000cf3ce000 (ACPI data) (XEN) 00000000cf3ce000 - 00000000d0000000 (reserved) (XEN) 00000000e0000000 - 00000000f0000000 (reserved) (XEN) 00000000fe000000 - 0000000100000000 (reserved) (XEN) 0000000100000000 - 0000000630000000 (usable) Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-08-20x86/xen: disable premption when enabling local irqsDavid Vrabel
If CONFIG_PREEMPT is enabled then xen_enable_irq() (and xen_restore_fl()) could be preempted and rescheduled on a different VCPU in between the clear of the mask and the check for pending events. This may result in events being lost as the upcall will check for pending events on the wrong VCPU. Fix this by disabling preemption around the unmask and check for events. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-08-20x86/xen: do not identity map UNUSABLE regions in the machine E820David Vrabel
If there are UNUSABLE regions in the machine memory map, dom0 will attempt to map them 1:1 which is not permitted by Xen and the kernel will crash. There isn't anything interesting in the UNUSABLE region that the dom0 kernel needs access to so we can avoid making the 1:1 mapping and treat it as RAM. We only do this for dom0, as that is where tboot case shows up. A PV domU could have an UNUSABLE region in its pseudo-physical map and would need to be handled in another patch. This fixes a boot failure on hosts with tboot. tboot marks a region in the e820 map as unusable and the dom0 kernel would attempt to map this region and Xen does not permit unusable regions to be mapped by guests. (XEN) 0000000000000000 - 0000000000060000 (usable) (XEN) 0000000000060000 - 0000000000068000 (reserved) (XEN) 0000000000068000 - 000000000009e000 (usable) (XEN) 0000000000100000 - 0000000000800000 (usable) (XEN) 0000000000800000 - 0000000000972000 (unusable) tboot marked this region as unusable. (XEN) 0000000000972000 - 00000000cf200000 (usable) (XEN) 00000000cf200000 - 00000000cf38f000 (reserved) (XEN) 00000000cf38f000 - 00000000cf3ce000 (ACPI data) (XEN) 00000000cf3ce000 - 00000000d0000000 (reserved) (XEN) 00000000e0000000 - 00000000f0000000 (reserved) (XEN) 00000000fe000000 - 0000000100000000 (reserved) (XEN) 0000000100000000 - 0000000630000000 (usable) Signed-off-by: David Vrabel <david.vrabel@citrix.com> [v1: Altered the patch and description with domU's with UNUSABLE regions] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-08-20x86/mm: Fix boot crash with DEBUG_PAGE_ALLOC=y and more than 512G RAMYinghai Lu
Dave Hansen reported that systems between 500G and 600G RAM crash early if DEBUG_PAGEALLOC is selected. > [ 0.000000] init_memory_mapping: [mem 0x00000000-0x000fffff] > [ 0.000000] [mem 0x00000000-0x000fffff] page 4k > [ 0.000000] BRK [0x02086000, 0x02086fff] PGTABLE > [ 0.000000] BRK [0x02087000, 0x02087fff] PGTABLE > [ 0.000000] BRK [0x02088000, 0x02088fff] PGTABLE > [ 0.000000] init_memory_mapping: [mem 0xe80ee00000-0xe80effffff] > [ 0.000000] [mem 0xe80ee00000-0xe80effffff] page 4k > [ 0.000000] BRK [0x02089000, 0x02089fff] PGTABLE > [ 0.000000] BRK [0x0208a000, 0x0208afff] PGTABLE > [ 0.000000] Kernel panic - not syncing: alloc_low_page: ran out of memory It turns out that we missed increasing needed pages in BRK to mapping initial 2M and [0,1M) when we switched to use the #PF handler to set memory mappings: > commit 8170e6bed465b4b0c7687f93e9948aca4358a33b > Author: H. Peter Anvin <hpa@zytor.com> > Date: Thu Jan 24 12:19:52 2013 -0800 > > x86, 64bit: Use a #PF handler to materialize early mappings on demand Before that, we had the maping from [0,512M) in head_64.S, and we can spare two pages [0-1M). After that change, we can not reuse pages anymore. When we have more than 512M ram, we need an extra page for pgd page with [512G, 1024g). Increase pages in BRK for page table to solve the boot crash. Reported-by: Dave Hansen <dave.hansen@intel.com> Bisected-by: Dave Hansen <dave.hansen@intel.com> Tested-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: <stable@vger.kernel.org> # v3.9 and later Link: http://lkml.kernel.org/r/1376351004-4015-1-git-send-email-yinghai@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-20x86/ioapic/kcrash: Prevent crash_kexec() from deadlocking on ioapic_lockYoshihiro YUNOMAE
Prevent crash_kexec() from deadlocking on ioapic_lock. When crash_kexec() is executed on a CPU, the CPU will take ioapic_lock in disable_IO_APIC(). So if the cpu gets an NMI while locking ioapic_lock, a deadlock will happen. In this patch, ioapic_lock is zapped/initialized before disable_IO_APIC(). You can reproduce this deadlock the following way: 1. Add mdelay(1000) after raw_spin_lock_irqsave() in native_ioapic_set_affinity()@arch/x86/kernel/apic/io_apic.c Although the deadlock can occur without this modification, it will increase the potential of the deadlock problem. 2. Build and install the kernel 3. Set up the OS which will run panic() and kexec when NMI is injected # echo "kernel.unknown_nmi_panic=1" >> /etc/sysctl.conf # vim /etc/default/grub add "nmi_watchdog=0 crashkernel=256M" in GRUB_CMDLINE_LINUX line # grub2-mkconfig 4. Reboot the OS 5. Run following command for each vcpu on the guest # while true; do echo <CPU num> > /proc/irq/<IO-APIC-edge or IO-APIC-fasteoi>/smp_affinitity; done; By running this command, cpus will get ioapic_lock for setting affinity. 6. Inject NMI (push a dump button or execute 'virsh inject-nmi <domain>' if you use VM). After injecting NMI, panic() is called in an nmi-handler context. Then, kexec will normally run in panic(), but the operation will be stopped by deadlock on ioapic_lock in crash_kexec()->machine_crash_shutdown()-> native_machine_crash_shutdown()->disable_IO_APIC()->clear_IO_APIC()-> clear_IO_APIC_pin()->ioapic_read_entry(). Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/20130820070107.28245.83806.stgit@yunodevel Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-19Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Two AMD microcode loader fixes and an OLPC firmware support fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode, AMD: Fix early microcode loading x86, microcode, AMD: Make cpu_has_amd_erratum() use the correct struct cpuinfo_x86 x86: Don't clear olpc_ofw_header when sentinel is detected