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2014-08-06avr32: Use get_signal() signal_setup_done()Richard Weinberger
Use the more generic functions get_signal() signal_setup_done() for signal delivery. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
2014-08-06arm64: Use get_signal() signal_setup_done()Richard Weinberger
Use the more generic functions get_signal() signal_setup_done() for signal delivery. Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-06arc: Use get_signal() signal_setup_done()Richard Weinberger
Use the more generic functions get_signal() signal_setup_done() for signal delivery. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2014-08-06s390/locking: Reenable optimistic spinningChristian Borntraeger
commit 4badad352a6bb202ec68afa7a574c0bb961e5ebc (locking/mutex: Disable optimistic spinning on some architectures) fenced spinning for architectures without proper cmpxchg. There is no need to disable mutex spinning on s390, though: The instructions CS,CSG and friends provide the proper guarantees. (We dont implement cmpxchg with locks). Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-08-05sparc64: Fix up merge thinko.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparcDavid S. Miller
Conflicts: arch/sparc/mm/init_64.c Conflict was simple non-overlapping additions. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-05Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer and time updates from Thomas Gleixner: "A rather large update of timers, timekeeping & co - Core timekeeping code is year-2038 safe now for 32bit machines. Now we just need to fix all in kernel users and the gazillion of user space interfaces which rely on timespec/timeval :) - Better cache layout for the timekeeping internal data structures. - Proper nanosecond based interfaces for in kernel users. - Tree wide cleanup of code which wants nanoseconds but does hoops and loops to convert back and forth from timespecs. Some of it definitely belongs into the ugly code museum. - Consolidation of the timekeeping interface zoo. - A fast NMI safe accessor to clock monotonic for tracing. This is a long standing request to support correlated user/kernel space traces. With proper NTP frequency correction it's also suitable for correlation of traces accross separate machines. - Checkpoint/restart support for timerfd. - A few NOHZ[_FULL] improvements in the [hr]timer code. - Code move from kernel to kernel/time of all time* related code. - New clocksource/event drivers from the ARM universe. I'm really impressed that despite an architected timer in the newer chips SoC manufacturers insist on inventing new and differently broken SoC specific timers. [ Ed. "Impressed"? I don't think that word means what you think it means ] - Another round of code move from arch to drivers. Looks like most of the legacy mess in ARM regarding timers is sorted out except for a few obnoxious strongholds. - The usual updates and fixlets all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits) timekeeping: Fixup typo in update_vsyscall_old definition clocksource: document some basic timekeeping concepts timekeeping: Use cached ntp_tick_length when accumulating error timekeeping: Rework frequency adjustments to work better w/ nohz timekeeping: Minor fixup for timespec64->timespec assignment ftrace: Provide trace clocks monotonic timekeeping: Provide fast and NMI safe access to CLOCK_MONOTONIC seqcount: Add raw_write_seqcount_latch() seqcount: Provide raw_read_seqcount() timekeeping: Use tk_read_base as argument for timekeeping_get_ns() timekeeping: Create struct tk_read_base and use it in struct timekeeper timekeeping: Restructure the timekeeper some more clocksource: Get rid of cycle_last clocksource: Move cycle_last validation to core code clocksource: Make delta calculation a function wireless: ath9k: Get rid of timespec conversions drm: vmwgfx: Use nsec based interfaces drm: i915: Use nsec based interfaces timekeeping: Provide ktime_get_raw() hangcheck-timer: Use ktime_get_ns() ...
2014-08-05Merge branch 'irq-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Nothing spectacular from the irq department this time: - overhaul of the crossbar chip driver - overhaul of the spear shirq chip driver - support for the atmel-aic chip - code move from arch to drivers - the usual tiny fixlets - two reverts worth to mention which undo the too simple attempt of supporting wakeup interrupts on shared interrupt lines" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits) Revert "irq: Warn when shared interrupts do not match on NO_SUSPEND" Revert "PM / sleep / irq: Do not suspend wakeup interrupts" irq: Warn when shared interrupts do not match on NO_SUSPEND irqchip: atmel-aic: Define irq fixups for atmel SoCs irqchip: atmel-aic: Implement RTC irq fixup irqchip: atmel-aic: Add irq fixup infrastructure irqchip: atmel-aic: Add atmel AIC/AIC5 drivers irqchip: atmel-aic: Move binding doc to interrupt-controller directory genirq: generic chip: Export irq_map_generic_chip function PM / sleep / irq: Do not suspend wakeup interrupts irqchip: or1k-pic: Migrate from arch/openrisc/ irqchip: crossbar: Allow for quirky hardware with direct hardwiring of GIC documentation: dt: omap: crossbar: Add description for interrupt consumer irqchip: crossbar: Introduce centralized check for crossbar write irqchip: crossbar: Introduce ti, max-crossbar-sources to identify valid crossbar mapping irqchip: crossbar: Add kerneldoc for crossbar_domain_unmap callback irqchip: crossbar: Set cb pointer to null in case of error irqchip: crossbar: Change the goto naming irqchip: crossbar: Return proper error value irqchip: crossbar: Fix kerneldoc warning ...
2014-08-05x86: MCE: Add raw_lock conversion againThomas Gleixner
Commit ea431643d6c3 ("x86/mce: Fix CMCI preemption bugs") breaks RT by the completely unrelated conversion of the cmci_discover_lock to a regular (non raw) spinlock. This lock was annotated in commit 59d958d2c7de ("locking, x86: mce: Annotate cmci_discover_lock as raw") with a proper explanation why. The argument for converting the lock back to a regular spinlock was: - it does percpu ops without disabling preemption. Preemption is not disabled due to the mistaken use of a raw spinlock. Which is complete nonsense. The raw_spinlock is disabling preemption in the same way as a regular spinlock. In mainline spinlock maps to raw_spinlock, in RT spinlock becomes a "sleeping" lock. raw_spinlock has on RT exactly the same semantics as in mainline. And because this lock is taken in non preemptible context it must be raw on RT. Undo the locking brainfart. Reported-by: Clark Williams <williams@redhat.com> Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-05Merge tag 'spi-v3.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi Pull spi updates from Mark Brown: "A quiet release, more bug fixes than anything else. A few things do stand out though: - updates to several drivers to move towards the standard GPIO chip select handling in the core. - DMA support for the SH MSIOF driver. - support for Rockchip SPI controllers (their first mainline submission)" * tag 'spi-v3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (64 commits) spi: davinci: use spi_device.cs_gpio to store gpio cs per spi device spi: davinci: add support to configure gpio cs through dt spi/pl022: Explicitly truncate large bitmask spi/atmel: Fix pointer to int conversion warnings on 64 bit builds spi: davinci: fix to support more than 2 chip selects spi: topcliff-pch: don't hardcode PCI slot to get DMA device spi: orion: fix incorrect handling of cell-index DT property spi: orion: Fix error return code in orion_spi_probe() spi/rockchip: fix error return code in rockchip_spi_probe() spi/rockchip: remove redundant dev_err call in rockchip_spi_probe() spi/rockchip: remove duplicated include from spi-rockchip.c ARM: dts: fix the chip select gpios definition in the SPI nodes spi: s3c64xx: Update binding documentation spi: s3c64xx: use the generic SPI "cs-gpios" property spi: s3c64xx: Revert "spi: s3c64xx: Added provision for dedicated cs pin" spi: atmel: Use dmaengine_prep_slave_sg() API spi: topcliff-pch: Update error messages for dmaengine_prep_slave_sg() API spi: sh-msiof: Use correct device for DMA mapping with IOMMU spi: sh-msiof: Handle dmaengine_prep_slave_single() failures gracefully spi: rspi: Handle dmaengine_prep_slave_sg() failures gracefully ...
2014-08-05Merge tag 'iommu-updates-v3.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull iommu updates from Joerg Roedel: "This time with: - support for the generic PCI device alias code in x86 IOMMU drivers - a new sysfs interface for IOMMUs - preparations for hotplug support in the Intel IOMMU driver - change the AMD IOMMUv2 driver to not hold references to core data structures like mm_struct or task_struct. Rely on mmu_notifers instead. - removal of the OMAP IOVMM interface, all users of it are converted to DMA-API now - make the struct iommu_ops const everywhere - initial PCI support for the ARM SMMU driver - there is now a generic device tree binding documented for ARM IOMMUs - various fixes and cleanups all over the place Also included are some changes to the OMAP code, which are acked by the maintainer" * tag 'iommu-updates-v3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (67 commits) devicetree: Add generic IOMMU device tree bindings iommu/vt-d: Fix race setting IRQ CPU affinity while freeing IRQ iommu/amd: Fix 2 typos in comments iommu/amd: Fix device_state reference counting iommu/amd: Remove change_pte mmu_notifier call-back iommu/amd: Don't set pasid_state->mm to NULL in unbind_pasid iommu/exynos: Select ARM_DMA_USE_IOMMU iommu/vt-d: Exclude devices using RMRRs from IOMMU API domains iommu/omap: Remove platform data da_start and da_end fields ARM: omap: Don't set iommu pdata da_start and da_end fields iommu/omap: Remove virtual memory manager iommu/vt-d: Fix issue in computing domain's iommu_snooping flag iommu/vt-d: Introduce helper function iova_size() to improve code readability iommu/vt-d: Introduce helper domain_pfn_within_range() to simplify code iommu/vt-d: Simplify intel_unmap_sg() and kill duplicated code iommu/vt-d: Change iommu_enable/disable_translation to return void iommu/vt-d: Simplify include/linux/dmar.h iommu/vt-d: Avoid freeing virtual machine domain in free_dmar_iommu() iommu/vt-d: Fix possible invalid memory access caused by free_dmar_iommu() iommu/vt-d: Allocate dynamic domain id for virtual domains only ...
2014-08-05x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stubMatt Fleming
Without CONFIG_RELOCATABLE the early boot code will decompress the kernel to LOAD_PHYSICAL_ADDR. While this may have been fine in the BIOS days, that isn't going to fly with UEFI since parts of the firmware code/data may be located at LOAD_PHYSICAL_ADDR. Straying outside of the bounds of the regions we've explicitly requested from the firmware will cause all sorts of trouble. Bruno reports that his machine resets while trying to decompress the kernel image. We already go to great pains to ensure the kernel is loaded into a suitably aligned buffer, it's just that the address isn't necessarily LOAD_PHYSICAL_ADDR, because we can't guarantee that address isn't in-use by the firmware. Explicitly enforce CONFIG_RELOCATABLE for the EFI boot stub, so that we can load the kernel at any address with the correct alignment. Reported-by: Bruno Prémont <bonbons@linux-vserver.org> Tested-by: Bruno Prémont <bonbons@linux-vserver.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-08-05random: introduce getrandom(2) system callTheodore Ts'o
The getrandom(2) system call was requested by the LibreSSL Portable developers. It is analoguous to the getentropy(2) system call in OpenBSD. The rationale of this system call is to provide resiliance against file descriptor exhaustion attacks, where the attacker consumes all available file descriptors, forcing the use of the fallback code where /dev/[u]random is not available. Since the fallback code is often not well-tested, it is better to eliminate this potential failure mode entirely. The other feature provided by this new system call is the ability to request randomness from the /dev/urandom entropy pool, but to block until at least 128 bits of entropy has been accumulated in the /dev/urandom entropy pool. Historically, the emphasis in the /dev/urandom development has been to ensure that urandom pool is initialized as quickly as possible after system boot, and preferably before the init scripts start execution. This is because changing /dev/urandom reads to block represents an interface change that could potentially break userspace which is not acceptable. In practice, on most x86 desktop and server systems, in general the entropy pool can be initialized before it is needed (and in modern kernels, we will printk a warning message if not). However, on an embedded system, this may not be the case. And so with this new interface, we can provide the functionality of blocking until the urandom pool has been initialized. Any userspace program which uses this new functionality must take care to assure that if it is used during the boot process, that it will not cause the init scripts or other portions of the system startup to hang indefinitely. SYNOPSIS #include <linux/random.h> int getrandom(void *buf, size_t buflen, unsigned int flags); DESCRIPTION The system call getrandom() fills the buffer pointed to by buf with up to buflen random bytes which can be used to seed user space random number generators (i.e., DRBG's) or for other cryptographic uses. It should not be used for Monte Carlo simulations or other programs/algorithms which are doing probabilistic sampling. If the GRND_RANDOM flags bit is set, then draw from the /dev/random pool instead of the /dev/urandom pool. The /dev/random pool is limited based on the entropy that can be obtained from environmental noise, so if there is insufficient entropy, the requested number of bytes may not be returned. If there is no entropy available at all, getrandom(2) will either block, or return an error with errno set to EAGAIN if the GRND_NONBLOCK bit is set in flags. If the GRND_RANDOM bit is not set, then the /dev/urandom pool will be used. Unlike using read(2) to fetch data from /dev/urandom, if the urandom pool has not been sufficiently initialized, getrandom(2) will block (or return -1 with the errno set to EAGAIN if the GRND_NONBLOCK bit is set in flags). The getentropy(2) system call in OpenBSD can be emulated using the following function: int getentropy(void *buf, size_t buflen) { int ret; if (buflen > 256) goto failure; ret = getrandom(buf, buflen, 0); if (ret < 0) return ret; if (ret == buflen) return 0; failure: errno = EIO; return -1; } RETURN VALUE On success, the number of bytes that was filled in the buf is returned. This may not be all the bytes requested by the caller via buflen if insufficient entropy was present in the /dev/random pool, or if the system call was interrupted by a signal. On error, -1 is returned, and errno is set appropriately. ERRORS EINVAL An invalid flag was passed to getrandom(2) EFAULT buf is outside the accessible address space. EAGAIN The requested entropy was not available, and getentropy(2) would have blocked if the GRND_NONBLOCK flag was not set. EINTR While blocked waiting for entropy, the call was interrupted by a signal handler; see the description of how interrupted read(2) calls on "slow" devices are handled with and without the SA_RESTART flag in the signal(7) man page. NOTES For small requests (buflen <= 256) getrandom(2) will not return EINTR when reading from the urandom pool once the entropy pool has been initialized, and it will return all of the bytes that have been requested. This is the recommended way to use getrandom(2), and is designed for compatibility with OpenBSD's getentropy() system call. However, if you are using GRND_RANDOM, then getrandom(2) may block until the entropy accounting determines that sufficient environmental noise has been gathered such that getrandom(2) will be operating as a NRBG instead of a DRBG for those people who are working in the NIST SP 800-90 regime. Since it may block for a long time, these guarantees do *not* apply. The user may want to interrupt a hanging process using a signal, so blocking until all of the requested bytes are returned would be unfriendly. For this reason, the user of getrandom(2) MUST always check the return value, in case it returns some error, or if fewer bytes than requested was returned. In the case of !GRND_RANDOM and small request, the latter should never happen, but the careful userspace code (and all crypto code should be careful) should check for this anyway! Finally, unless you are doing long-term key generation (and perhaps not even then), you probably shouldn't be using GRND_RANDOM. The cryptographic algorithms used for /dev/urandom are quite conservative, and so should be sufficient for all purposes. The disadvantage of GRND_RANDOM is that it can block, and the increased complexity required to deal with partially fulfilled getrandom(2) requests. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Zach Brown <zab@zabbo.net>
2014-08-05Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: "Included in this update: - perf updates from Will Deacon: The main changes are callchain stability fixes from Jean Pihet and event mapping and PMU name rework from Mark Rutland The latter is preparatory work for enabling some code re-use with arm64 in the future. - updates for nommu from Uwe Kleine-König: Two different fixes for the same problem making some ARM nommu configurations not boot since 3.6-rc1. The problem is that user_addr_max returned the biggest available RAM address which makes some copy_from_user variants fail to read from XIP memory. - deprecate legacy OMAP DMA API, in preparation for it's removal. The popular drivers have been converted over, leaving a very small number of rarely used drivers, which hopefully can be converted during the next cycle with a bit more visibility (and hopefully people popping out of the woodwork to help test) - more tweaks for BE systems, particularly with the kernel image format. In connection with this, I've cleaned up the way we generate the linker script for the decompressor. - removal of hard-coded assumptions of the kernel stack size, making everywhere depend on the value of THREAD_SIZE_ORDER. - MCPM updates from Nicolas Pitre. - Make it easier for proper CPU part number checks (which should always include the vendor field). - Assembly code optimisation - use the "bx" instruction when returning from a function on ARMv6+ rather than "mov pc, reg". - Save the last kernel misaligned fault location and report it via the procfs alignment file. - Clean up the way we create the initial stack frame, which is a repeated pattern in several different locations. - Support for 8-byte get_user(), needed for some DRM implementations. - mcs locking from Will Deacon. - Save and restore a few more Cortex-A9 registers (for errata workarounds) - Fix various aspects of the SWP emulation, and the ELF hwcap for the SWP instruction. - Update LPAE logic for pte_write and pmd_write to make it more correct. - Support for Broadcom Brahma15 CPU cores. - ARM assembly crypto updates from Ard Biesheuvel" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (53 commits) ARM: add comments to the early page table remap code ARM: 8122/1: smp_scu: enable SCU standby support ARM: 8121/1: smp_scu: use macro for SCU enable bit ARM: 8120/1: crypto: sha512: add ARM NEON implementation ARM: 8119/1: crypto: sha1: add ARM NEON implementation ARM: 8118/1: crypto: sha1/make use of common SHA-1 structures ARM: 8113/1: remove remaining definitions of PLAT_PHYS_OFFSET from <mach/memory.h> ARM: 8111/1: Enable erratum 798181 for Broadcom Brahma-B15 ARM: 8110/1: do CPU-specific init for Broadcom Brahma15 cores ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear ARM: hwcap: disable HWCAP_SWP if the CPU advertises it has exclusives ARM: SWP emulation: only initialise on ARMv7 CPUs ARM: SWP emulation: always enable when SMP is enabled ARM: 8103/1: save/restore Cortex-A9 CP15 registers on suspend/resume ARM: 8098/1: mcs lock: implement wfe-based polling for MCS locking ARM: 8091/2: add get_user() support for 8 byte types ARM: 8097/1: unistd.h: relocate comments back to place ARM: 8096/1: Describe required sort order for textofs-y (TEXT_OFFSET) ARM: 8090/1: add revision info for PL310 errata 588369 and 727915 ...
2014-08-05Merge branch 'for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu Pull m68knommu fixes from Greg Ungerer: "Just a couple of small fixes. Fix definition of page_to_phys() and remove unecesary prototype of kobjsize()" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68knommu: Remove unnecessary prototype for kobjsize() m68knommu: Correct page_to_phys when PAGE_OFFSET is non-zero.
2014-08-05KVM: nVMX: fix "acknowledge interrupt on exit" when APICv is in useWanpeng Li
After commit 77b0f5d (KVM: nVMX: Ack and write vector info to intr_info if L1 asks us to), "Acknowledge interrupt on exit" behavior can be emulated. To do so, KVM will ask the APIC for the interrupt vector if during a nested vmexit if VM_EXIT_ACK_INTR_ON_EXIT is set. With APICv, kvm_get_apic_interrupt would return -1 and give the following WARNING: Call Trace: [<ffffffff81493563>] dump_stack+0x49/0x5e [<ffffffff8103f0eb>] warn_slowpath_common+0x7c/0x96 [<ffffffffa059709a>] ? nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffff8103f11a>] warn_slowpath_null+0x15/0x17 [<ffffffffa059709a>] nested_vmx_vmexit+0xa4/0x233 [kvm_intel] [<ffffffffa0594295>] ? nested_vmx_exit_handled+0x6a/0x39e [kvm_intel] [<ffffffffa0537931>] ? kvm_apic_has_interrupt+0x80/0xd5 [kvm] [<ffffffffa05972ec>] vmx_check_nested_events+0xc3/0xd3 [kvm_intel] [<ffffffffa051ebe9>] inject_pending_event+0xd0/0x16e [kvm] [<ffffffffa051efa0>] vcpu_enter_guest+0x319/0x704 [kvm] To fix this, we cannot rely on the processor's virtual interrupt delivery, because "acknowledge interrupt on exit" must only update the virtual ISR/PPR/IRR registers (and SVI, which is just a cache of the virtual ISR) but it should not deliver the interrupt through the IDT. Thus, KVM has to deliver the interrupt "by hand", similar to the treatment of EOI in commit fc57ac2c9ca8 (KVM: lapic: sync highest ISR to hardware apic on EOI, 2014-05-14). The patch modifies kvm_cpu_get_interrupt to always acknowledge an interrupt; there are only two callers, and the other is not affected because it is never reached with kvm_apic_vid_enabled() == true. Then it modifies apic_set_isr and apic_clear_irr to update SVI and RVI in addition to the registers. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Suggested-by: "Zhang, Yang Z" <yang.z.zhang@intel.com> Tested-by: Liu, RongrongX <rongrongx.liu@intel.com> Tested-by: Felipe Reyes <freyes@suse.com> Fixes: 77b0f5d67ff2781f36831cba79674c3e97bd7acf Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-05KVM: nVMX: Fix nested vmexit ack intr before load vmcs01Wanpeng Li
An external interrupt will cause a vmexit with reason "external interrupt" when L2 is running. L1 will pick up the interrupt through vmcs12 if L1 set the ack interrupt bit. Commit 77b0f5d (KVM: nVMX: Ack and write vector info to intr_info if L1 asks us to) retrieves the interrupt that belongs to L1 before vmcs01 is loaded. This will lead to problems in the next patch, which would write to SVI of vmcs02 instead of vmcs01 (SVI of vmcs02 doesn't make sense because L2 runs without APICv). Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Liu, RongrongX <rongrongx.liu@intel.com> Tested-by: Felipe Reyes <freyes@suse.com> Fixes: 77b0f5d67ff2781f36831cba79674c3e97bd7acf Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> [Move tracepoint as well. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-05KVM: PPC: Enable IRQFD support for the XICS interrupt controllerPaul Mackerras
This makes it possible to use IRQFDs on platforms that use the XICS interrupt controller. To do this we implement kvm_irq_map_gsi() and kvm_irq_map_chip_pin() in book3s_xics.c, so as to provide a 1-1 mapping between global interrupt numbers and XICS interrupt source numbers. For now, all interrupts are mapped as "IRQCHIP" interrupts, and no MSI support is provided. This means that kvm_set_irq can now get called with level == 0 or 1 as well as the powerpc-specific values KVM_INTERRUPT_SET, KVM_INTERRUPT_UNSET and KVM_INTERRUPT_SET_LEVEL. We change ics_deliver_irq() to accept all those values, and remove its report_status argument, as it is always false, given that we don't support KVM_IRQ_LINE_STATUS. This also adds support for interrupt ack notifiers to the XICS code so that the IRQFD resampler functionality can be supported. Signed-off-by: Paul Mackerras <paulus@samba.org> Tested-by: Eric Auger <eric.auger@linaro.org> Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-05KVM: Give IRQFD its own separate enabling Kconfig optionPaul Mackerras
Currently, the IRQFD code is conditional on CONFIG_HAVE_KVM_IRQ_ROUTING. So that we can have the IRQFD code compiled in without having the IRQ routing code, this creates a new CONFIG_HAVE_KVM_IRQFD, makes the IRQFD code conditional on it instead of CONFIG_HAVE_KVM_IRQ_ROUTING, and makes all the platforms that currently select HAVE_KVM_IRQ_ROUTING also select HAVE_KVM_IRQFD. Signed-off-by: Paul Mackerras <paulus@samba.org> Tested-by: Eric Auger <eric.auger@linaro.org> Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-05KVM: irqchip: Provide and use accessors for irq routing tablePaul Mackerras
This provides accessor functions for the KVM interrupt mappings, in order to reduce the amount of code that accesses the fields of the kvm_irq_routing_table struct, and restrict that code to one file, virt/kvm/irqchip.c. The new functions are kvm_irq_map_gsi(), which maps from a global interrupt number to a set of IRQ routing entries, and kvm_irq_map_chip_pin, which maps from IRQ chip and pin numbers to a global interrupt number. This also moves the update of kvm_irq_routing_table::chip[][] into irqchip.c, out of the various kvm_set_routing_entry implementations. That means that none of the kvm_set_routing_entry implementations need the kvm_irq_routing_table argument anymore, so this removes it. This does not change any locking or data lifetime rules. Signed-off-by: Paul Mackerras <paulus@samba.org> Tested-by: Eric Auger <eric.auger@linaro.org> Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-05KVM: PPC: drop duplicate tracepointPaolo Bonzini
Commit 29577fc00ba4 ("KVM: PPC: HV: Remove generic instruction emulation") caused a build failure with allyesconfig: arch/powerpc/kvm/kvm-pr.o:(__tracepoints+0xa8): multiple definition of `__tracepoint_kvm_ppc_instr' arch/powerpc/kvm/kvm.o:(__tracepoints+0x1c0): first defined here due to a duplicate definition of the tracepoint in trace.h and trace_pr.h. Because the tracepoint is still used by Book3S HV code, and because the PR code does include trace.h, just remove the duplicate definition from trace_pr.h, and export it from kvm.o. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-05Merge branch 'devel-stable' into for-nextRussell King
Conflicts: arch/arm/kernel/perf_event_cpu.c
2014-08-05Merge branch 'swp' (early part) into for-nextRussell King
2014-08-05Merge branches 'fixes' and 'misc' into for-nextRussell King
Conflicts: arch/arm/kernel/iwmmxt.S arch/arm/mm/cache-l2x0.c arch/arm/mm/mmu.c
2014-08-05powerpc/eeh: Add missing #ifdef CONFIG_IOMMU_APIBenjamin Herrenschmidt
Some new functions are exposed for use by the IOMMU code but won't build when CONFIG_IOMMU_API isn't set, so shield them appropriately. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvmPaolo Bonzini
Patch queue for ppc - 2014-08-01 Highlights in this release include: - BookE: Rework instruction fetch, not racy anymore now - BookE HV: Fix ONE_REG accessors for some in-hardware registers - Book3S: Good number of LE host fixes, enable HV on LE - Book3S: Some misc bug fixes - Book3S HV: Add in-guest debug support - Book3S HV: Preload cache lines on context switch - Remove 440 support Alexander Graf (31): KVM: PPC: Book3s PR: Disable AIL mode with OPAL KVM: PPC: Book3s HV: Fix tlbie compile error KVM: PPC: Book3S PR: Handle hyp doorbell exits KVM: PPC: Book3S PR: Fix ABIv2 on LE KVM: PPC: Book3S PR: Fix sparse endian checks PPC: Add asm helpers for BE 32bit load/store KVM: PPC: Book3S HV: Make HTAB code LE host aware KVM: PPC: Book3S HV: Access guest VPA in BE KVM: PPC: Book3S HV: Access host lppaca and shadow slb in BE KVM: PPC: Book3S HV: Access XICS in BE KVM: PPC: Book3S HV: Fix ABIv2 on LE KVM: PPC: Book3S HV: Enable for little endian hosts KVM: PPC: Book3S: Move vcore definition to end of kvm_arch struct KVM: PPC: Deflect page write faults properly in kvmppc_st KVM: PPC: Book3S: Stop PTE lookup on write errors KVM: PPC: Book3S: Add hack for split real mode KVM: PPC: Book3S: Make magic page properly 4k mappable KVM: PPC: Remove 440 support KVM: Rename and add argument to check_extension KVM: Allow KVM_CHECK_EXTENSION on the vm fd KVM: PPC: Book3S: Provide different CAPs based on HV or PR mode KVM: PPC: Implement kvmppc_xlate for all targets KVM: PPC: Move kvmppc_ld/st to common code KVM: PPC: Remove kvmppc_bad_hva() KVM: PPC: Use kvm_read_guest in kvmppc_ld KVM: PPC: Handle magic page in kvmppc_ld/st KVM: PPC: Separate loadstore emulation from priv emulation KVM: PPC: Expose helper functions for data/inst faults KVM: PPC: Remove DCR handling KVM: PPC: HV: Remove generic instruction emulation KVM: PPC: PR: Handle FSCR feature deselects Alexey Kardashevskiy (1): KVM: PPC: Book3S: Fix LPCR one_reg interface Aneesh Kumar K.V (4): KVM: PPC: BOOK3S: PR: Fix PURR and SPURR emulation KVM: PPC: BOOK3S: PR: Emulate virtual timebase register KVM: PPC: BOOK3S: PR: Emulate instruction counter KVM: PPC: BOOK3S: HV: Update compute_tlbie_rb to handle 16MB base page Anton Blanchard (2): KVM: PPC: Book3S HV: Fix ABIv2 indirect branch issue KVM: PPC: Assembly functions exported to modules need _GLOBAL_TOC() Bharat Bhushan (10): kvm: ppc: bookehv: Added wrapper macros for shadow registers kvm: ppc: booke: Use the shared struct helpers of SRR0 and SRR1 kvm: ppc: booke: Use the shared struct helpers of SPRN_DEAR kvm: ppc: booke: Add shared struct helpers of SPRN_ESR kvm: ppc: booke: Use the shared struct helpers for SPRN_SPRG0-7 kvm: ppc: Add SPRN_EPR get helper function kvm: ppc: bookehv: Save restore SPRN_SPRG9 on guest entry exit KVM: PPC: Booke-hv: Add one reg interface for SPRG9 KVM: PPC: Remove comment saying SPRG1 is used for vcpu pointer KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr Michael Neuling (1): KVM: PPC: Book3S HV: Add H_SET_MODE hcall handling Mihai Caraman (8): KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule KVM: PPC: e500: Fix default tlb for victim hint KVM: PPC: e500: Emulate power management control SPR KVM: PPC: e500mc: Revert "add load inst fixup" KVM: PPC: Book3e: Add TLBSEL/TSIZE defines for MAS0/1 KVM: PPC: Book3s: Remove kvmppc_read_inst() function KVM: PPC: Allow kvmppc_get_last_inst() to fail KVM: PPC: Bookehv: Get vcpu's last instruction for emulation Paul Mackerras (4): KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling KVM: PPC: Book3S: Allow only implemented hcalls to be enabled or disabled KVM: PPC: Book3S PR: Take SRCU read lock around RTAS kvm_read_guest() call KVM: PPC: Book3S: Make kvmppc_ld return a more accurate error indication Stewart Smith (2): Split out struct kvmppc_vcore creation to separate function Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8 Conflicts: Documentation/virtual/kvm/api.txt
2014-08-05Merge tag 'kvm-arm-for-3.17' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm KVM/ARM New features for 3.17 include: - Fixes and code refactoring for stage2 kvm MMU unmap_range - Support unmapping IPAs on deleting memslots for arm and arm64 - Support MMIO mappings in stage2 faults - KVM VGIC v2 emulation on GICv3 hardware - Big-Endian support for arm/arm64 (guest and host) - Debug Architecture support for arm64 (arm32 is on Christoffer's todo list) Conflicts: virt/kvm/arm/vgic.c [last minute cherry-pick from 3.17 to 3.16]
2014-08-05powerpc: Reduce scariness of interrupt frames in stack tracesPaul Mackerras
Some people see things like "Exception: 501" in stack traces in dmesg and assume that means that something has gone badly wrong, when in fact "Exception: 501" just means a device interrupt was taken. This changes "Exception" to "interrupt" to make it clearer that we are just recording the fact of a change in control flow rather than some error condition. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc: start loop at section start of start in vmemmap_populated()Li Zhong
vmemmap_populated() checks whether the [start, start + page_size) has valid pfn numbers, to know whether a vmemmap mapping has been created that includes this range. Some range before end might not be checked by this loop: sec11start......start11..sec11end/sec12start..end....start12..sec12end as the above, for start11(section 11), it checks [sec11start, sec11end), and loop ends as the next start(start12) is bigger than end. However, [sec11end/sec12start, end) is not checked here. So before the loop, adjust the start to be the start of the section, so we don't miss ranges like the above. After we adjust start to be the start of the section, it also means it's aligned with vmemmap as of the sizeof struct page, so we could use page_to_pfn directly in the loop. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc: implement vmemmap_free()Li Zhong
vmemmap_free() does the opposite of vmemap_populate(). This patch also puts vmemmap_free() and vmemmap_list_free() into CONFIG_MEMMORY_HOTPLUG. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc: implement vmemmap_remove_mapping() for BOOK3SLi Zhong
This is to be called in vmemmap_free(), leave the implementation on BOOK3E empty as before. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc: implement vmemmap_list_free()Li Zhong
This patch implements vmemmap_list_free() for vmemmap_free(). The freed entries will be removed from vmemmap_list, and form a freed list, with next as the header. The next position in the last allocated page is kept at the list tail. When allocation, if there are freed entries left, get it from the freed list; if no freed entries left, get it like before from the last allocated pages. With this change, realmode_pfn_to_page() also needs to be changed to walk all the entries in the vmemmap_list, as the virt_addr of the entries might not be stored in order anymore. It helps to reuse the memory when continuous doing memory hot-plug/remove operations, but didn't reclaim the pages already allocated, so the memory usage will only increase, but won't exceed the value for the largest memory configuration. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc: Fail remap_4k_pfn() if PFN doesn't fit inside PTEMadhusudanan Kandasamy
remap_4k_pfn() silently truncates upper bits of input 4K PFN if it cannot be contained in PTE. This leads invalid memory mapping and could result in a system crash when the memory is accessed. This patch fails remap_4k_pfn() and returns -EINVAL if the input 4K PFN cannot be contained in PTE. V3 : Added parentheses to protect 'pfn' and entire macro as suggested by Brian. V2 : Rewritten to avoid helper function as suggested by Stephen Rothwell. Signed-off-by: Madhusudanan Kandasamy <kmadhu@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/book3s: Fix endianess issue for HMI handling on napping cpus.Mahesh Salgaonkar
(NOTE: This patch depends on upstream HMI handling patchset at https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-July/119731.html) The current HMI handling on napping cpus does not take care of endianess issue. On LE host kernel when we wake up from nap due to HMI interrupt we would checkstop while jumping into opal call. There is a similar issue in case of fast sleep wakeup where the code invokes opal_resync_tb opal call without handling LE issue. This patch fixes that as well. With this patch applied, HMIs handling on LE host kernel works fine. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/book3s: handle HMIs for cpus in nap mode.Mahesh Salgaonkar
HMIs are thread specific and can come while thread is in sleep/nap mode. Hence with SMT=off mode we can receive HMIs on sleeping threads. For interrupt received in nap mode, cpu wakes up at system reset vector, clears the interrupt and go back to nap mode again. But HMIs are sticky and they keep happening until we clear reason bits from HMER. Hence add a special check for HMI in reset vector (through power7_wakeup_* functions) and invoke opal call to handle HMI. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Invoke opal call to handle hmi.Mahesh Salgaonkar
When we hit the HMI in Linux, invoke opal call to handle/recover from HMI errors in real mode and then in virtual mode during check_irq_replay() invoke opal_poll_events()/opal_do_notifier() to retrieve HMI event from OPAL and act accordingly. Now that we are ready to handle HMI interrupt directly in linux, remove the HMI interrupt registration with firmware. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/book3s: Add basic infrastructure to handle HMI in Linux.Mahesh Salgaonkar
Handle Hypervisor Maintenance Interrupt (HMI) in Linux. This patch implements basic infrastructure to handle HMI in Linux host. The design is to invoke opal handle hmi in real mode for recovery and set irq_pending when we hit HMI. During check_irq_replay pull opal hmi event and print hmi info on console. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/iommu: Fix comments with it_page_shiftAlexey Kardashevskiy
There is a couple of commented debug prints which still use IOMMU_PAGE_SHIFT() which is not defined for POWERPC anymore, replace them with it_page_shift. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Handle compound PE in config accessorsGavin Shan
The PCI config accessors check for PE frozen state and clear it if EEH isn't functional. The patch handles compound PE in config accessors if PHB supports it. For consistency, all PEs will be put into frozen state if any one in compound group gets frozen by hardware. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Handle compound PE for EEHGavin Shan
The patch handles compound PE for EEH backend. If one specific PE in compound group has been frozen, we enforces to freeze all PEs in the group. If we're enable DMA or MMIO for one PE in compound group, DMA or MMIO of all PEs in the group will be enabled. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Handle compound PEGavin Shan
The patch introduces 3 PHB callbacks: compound PE state retrieval, force freezing and unfreezing compound PE. The PCI config accessors and PowerNV EEH backend can use them in subsequent patches. We don't export the capability of compound PE to EEH core, which helps avoiding more complexity to EEH core. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Split ioda_eeh_get_state()Gavin Shan
Function ioda_eeh_get_state() is used to fetch EEH state for PHB or PE. We're going to support compound PE and the function becomes more complicated with that. The patch splits the function into two functions for PHB and PE cases separately to improve readability. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Allow to freeze PEGavin Shan
The patch synchronizes header file with firmware to have new OPAL API opal_pci_eeh_freeze_set(), which is used to freeze the specified PE in order to support "compound" PE. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/powernv: Enable M64 aperatus for PHB3Guo Chao
This patch enables M64 aperatus for PHB3. We already had platform hook (ppc_md.pcibios_window_alignment) to affect the PCI resource assignment done in PCI core so that each PE's M32 resource was built on basis of M32 segment size. Similarly, we're using that for M64 assignment on basis of M64 segment size. * We're using last M64 BAR to cover M64 aperatus, and it's shared by all 256 PEs. * We don't support P7IOC yet. However, some function callbacks are added to (struct pnv_phb) so that we can reuse them on P7IOC in future. * PE, corresponding to PCI bus with large M64 BAR device attached, might span multiple M64 segments. We introduce "compound" PE to cover the case. The compound PE is a list of PEs and the master PE is used as before. The slave PEs are just for MMIO isolation. Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Aux PE data for error logGavin Shan
The patch allows PE (struct eeh_pe) instance to have auxillary data, whose size is configurable on basis of platform. For PowerNV, the auxillary data will be used to cache PHB diag-data for that PE (frozen PE or fenced PHB). In turn, we can retrieve the diag-data at any later points. It's useful for the case of VFIO PCI devices where the error log should be cached, and then be retrieved by the guest at later point. Also, it can avoid PHB diag-data overwritting if another frozen PE reported and the previous diag-data isn't fetched by guest. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Make diag-data not endian dependentGavin Shan
It's followup of commit ddf0322a ("powerpc/powernv: Fix endianness problems in EEH"). The patch helps to get non-endian-dependent diag-data. Cc: Guo Chao <yan@linux.vnet.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Replace pr_warning() with pr_warn()Gavin Shan
pr_warn() is equal to pr_warning(), but the former is a bit more formal according to commit fc62f2f ("kernel.h: add pr_warn for symmetry to dev_warn, netdev_warn"). The patch replaces pr_warning() with pr_warn(). Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Reduce lines of log dumpGavin Shan
The patch prints 4 PCIE or AER config registers each line, which is part of the EEH log so that it looks a bit more compact. Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Selectively enable IO for error logGavin Shan
According to the experiment I did, PCI config access is blocked on P7IOC frozen PE by hardware, but PHB3 doesn't do that. That means we always get 0xFF's while dumping PCI config space of the frozen PE on P7IOC. We don't have the problem on PHB3. So we have to enable I/O prioir to collecting error log. Otherwise, meaningless 0xFF's are always returned. The patch fixes it by EEH flag (EEH_ENABLE_IO_FOR_LOG), which is selectively set to indicate the case for: P7IOC on PowerNV platform, pSeries platform. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Refactor EEH flag accessorsGavin Shan
There are multiple global EEH flags. Almost each flag has its own accessor, which doesn't make sense. The patch refactors EEH flag accessors so that they look unified: eeh_add_flag(): Add EEH flag eeh_clear_flag(): Clear EEH flag eeh_has_flag(): Check if one specific flag has been set eeh_enabled(): Check if EEH functionality has been enabled Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>