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* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2015-02-131-0/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM update from Paolo Bonzini: "Fairly small update, but there are some interesting new features. Common: Optional support for adding a small amount of polling on each HLT instruction executed in the guest (or equivalent for other architectures). This can improve latency up to 50% on some scenarios (e.g. O_DSYNC writes or TCP_RR netperf tests). This also has to be enabled manually for now, but the plan is to auto-tune this in the future. ARM/ARM64: The highlights are support for GICv3 emulation and dirty page tracking s390: Several optimizations and bugfixes. Also a first: a feature exposed by KVM (UUID and long guest name in /proc/sysinfo) before it is available in IBM's hypervisor! :) MIPS: Bugfixes. x86: Support for PML (page modification logging, a new feature in Broadwell Xeons that speeds up dirty page tracking), nested virtualization improvements (nested APICv---a nice optimization), usual round of emulation fixes. There is also a new option to reduce latency of the TSC deadline timer in the guest; this needs to be tuned manually. Some commits are common between this pull and Catalin's; I see you have already included his tree. Powerpc: Nothing yet. The KVM/PPC changes will come in through the PPC maintainers, because I haven't received them yet and I might end up being offline for some part of next week" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits) KVM: ia64: drop kvm.h from installed user headers KVM: x86: fix build with !CONFIG_SMP KVM: x86: emulate: correct page fault error code for NoWrite instructions KVM: Disable compat ioctl for s390 KVM: s390: add cpu model support KVM: s390: use facilities and cpu_id per KVM KVM: s390/CPACF: Choose crypto control block format s390/kernel: Update /proc/sysinfo file with Extended Name and UUID KVM: s390: reenable LPP facility KVM: s390: floating irqs: fix user triggerable endless loop kvm: add halt_poll_ns module parameter kvm: remove KVM_MMIO_SIZE KVM: MIPS: Don't leak FPU/DSP to guest KVM: MIPS: Disable HTW while in guest KVM: nVMX: Enable nested posted interrupt processing KVM: nVMX: Enable nested virtual interrupt delivery KVM: nVMX: Enable nested apic register virtualization KVM: nVMX: Make nested control MSRs per-cpu KVM: nVMX: Enable nested virtualize x2apic mode KVM: nVMX: Prepare for using hardware MSR bitmap ...
| * kvm: add halt_poll_ns module parameterPaolo Bonzini2015-02-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a new module parameter for the KVM module; when it is present, KVM attempts a bit of polling on every HLT before scheduling itself out via kvm_vcpu_block. This parameter helps a lot for latency-bound workloads---in particular I tested it with O_DSYNC writes with a battery-backed disk in the host. In this case, writes are fast (because the data doesn't have to go all the way to the platters) but they cannot be merged by either the host or the guest. KVM's performance here is usually around 30% of bare metal, or 50% if you use cache=directsync or cache=writethrough (these parameters avoid that the guest sends pointless flush requests, and at the same time they are not slow because of the battery-backed cache). The bad performance happens because on every halt the host CPU decides to halt itself too. When the interrupt comes, the vCPU thread is then migrated to a new physical CPU, and in general the latency is horrible because the vCPU thread has to be scheduled back in. With this patch performance reaches 60-65% of bare metal and, more important, 99% of what you get if you use idle=poll in the guest. This means that the tunable gets rid of this particular bottleneck, and more work can be done to improve performance in the kernel or QEMU. Of course there is some price to pay; every time an otherwise idle vCPUs is interrupted by an interrupt, it will poll unnecessarily and thus impose a little load on the host. The above results were obtained with a mostly random value of the parameter (500000), and the load was around 1.5-2.5% CPU usage on one of the host's core for each idle guest vCPU. The patch also adds a new stat, /sys/kernel/debug/kvm/halt_successful_poll, that can be used to tune the parameter. It counts how many HLT instructions received an interrupt during the polling period; each successful poll avoids that Linux schedules the VCPU thread out and back in, and may also avoid a likely trip to C1 and back for the physical CPU. While the VM is idle, a Linux 4 VCPU VM halts around 10 times per second. Of these halts, almost all are failed polls. During the benchmark, instead, basically all halts end within the polling period, except a more or less constant stream of 50 per second coming from vCPUs that are not running the benchmark. The wasted time is thus very low. Things may be slightly different for Windows VMs, which have a ~10 ms timer tick. The effect is also visible on Marcelo's recently-introduced latency test for the TSC deadline timer. Though of course a non-RT kernel has awful latency bounds, the latency of the timer is around 8000-10000 clock cycles compared to 20000-120000 without setting halt_poll_ns. For the TSC deadline timer, thus, the effect is both a smaller average latency and a smaller variance. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * arm/arm64: KVM: make the maximum number of vCPUs a per-VM valueAndre Przywara2015-01-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently the maximum number of vCPUs supported is a global value limited by the used GIC model. GICv3 will lift this limit, but we still need to observe it for guests using GICv2. So the maximum number of vCPUs is per-VM value, depending on the GIC model the guest uses. Store and check the value in struct kvm_arch, but keep it down to 8 for now. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * arm/arm64: KVM: rework MPIDR assignment and add accessorsAndre Przywara2015-01-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The virtual MPIDR registers (containing topology information) for the guest are currently mapped linearily to the vcpu_id. Improve this mapping for arm64 by using three levels to not artificially limit the number of vCPUs. To help this, change and rename the kvm_vcpu_get_mpidr() function to mask off the non-affinity bits in the MPIDR register. Also add an accessor to later allow easier access to a vCPU with a given MPIDR. Use this new accessor in the PSCI emulation. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * KVM: arm64: ARMv8 header changes for page loggingMario Smarduch2015-01-161-0/+1
| | | | | | | | | | | | | | | | | | This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
* | arm/arm64: KVM: Use set/way op trapping to track the state of the cachesMarc Zyngier2015-01-291-3/+0
|/ | | | | | | | | | | | | | | | | | Trying to emulate the behaviour of set/way cache ops is fairly pointless, as there are too many ways we can end-up missing stuff. Also, there is some system caches out there that simply ignore set/way operations. So instead of trying to implement them, let's convert it to VA ops, and use them as a way to re-enable the trapping of VM ops. That way, we can detect the point when the MMU/caches are turned off, and do a full VM flush (which is what the guest was trying to do anyway). This allows a 32bit zImage to boot on the APM thingy, and will probably help bootloaders in general. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* arm/arm64: KVM: Turn off vcpus on PSCI shutdown/rebootChristoffer Dall2014-12-131-0/+1
| | | | | | | | | | | | When a vcpu calls SYSTEM_OFF or SYSTEM_RESET with PSCI v0.2, the vcpus should really be turned off for the VM adhering to the suggestions in the PSCI spec, and it's the sane thing to do. Also, clarify the behavior and expectations for exits to user space with the KVM_EXIT_SYSTEM_EVENT case. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* arm/arm64: KVM: Clarify KVM_ARM_VCPU_INIT ABIChristoffer Dall2014-12-131-2/+0
| | | | | | | | | | | | | | | | | It is not clear that this ioctl can be called multiple times for a given vcpu. Userspace already does this, so clarify the ABI. Also specify that userspace is expected to always make secondary and subsequent calls to the ioctl with the same parameters for the VCPU as the initial call (which userspace also already does). Add code to check that userspace doesn't violate that ABI in the future, and move the kvm_vcpu_set_target() function which is currently duplicated between the 32-bit and 64-bit versions in guest.c to a common static function in arm.c, shared between both architectures. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* Merge tag 'kvm-arm-for-3.18' of ↵Paolo Bonzini2014-09-271-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next Changes for KVM for arm/arm64 for 3.18 This includes a bunch of changes: - Support read-only memory slots on arm/arm64 - Various changes to fix Sparse warnings - Correctly detect write vs. read Stage-2 faults - Various VGIC cleanups and fixes - Dynamic VGIC data strcuture sizing - Fix SGI set_clear_pend offset bug - Fix VTTBR_BADDR Mask - Correctly report the FSC on Stage-2 faults Conflicts: virt/kvm/eventfd.c [duplicate, different patch where the kvm-arm version broke x86. The kvm tree instead has the right one]
| * Merge remote-tracking branch 'kvm/next' into queueChristoffer Dall2014-09-181-4/+8
| |\ | | | | | | | | | | | | | | | Conflicts: arch/arm64/include/asm/kvm_host.h virt/kvm/arm/vgic.c
| * | KVM: ARM/arm64: fix broken __percpu annotationWill Deacon2014-08-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Running sparse results in a bunch of noisy address space mismatches thanks to the broken __percpu annotation on kvm_get_running_vcpus. This function returns a pcpu pointer to a pointer, not a pointer to a pcpu pointer. This patch fixes the annotation, which kills the warnings from sparse. Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | KVM: ARM/arm64: fix non-const declaration of function returning constWill Deacon2014-08-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sparse kicks up about a type mismatch for kvm_target_cpu: arch/arm64/kvm/guest.c:271:25: error: symbol 'kvm_target_cpu' redeclared with different type (originally declared at ./arch/arm64/include/asm/kvm_host.h:45) - different modifiers so fix this by adding the missing const attribute to the function declaration. Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* | | kvm: Add arch specific mmu notifier for page invalidationTang Chen2014-09-241-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This will be used to let the guest run while the APIC access page is not pinned. Because subsequent patches will fill in the function for x86, place the (still empty) x86 implementation in the x86.c file instead of adding an inline function in kvm_host.h. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | | kvm: Fix page ageing bugsAndres Lagar-Cavilla2014-09-241-1/+2
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. We were calling clear_flush_young_notify in unmap_one, but we are within an mmu notifier invalidate range scope. The spte exists no more (due to range_start) and the accessed bit info has already been propagated (due to kvm_pfn_set_accessed). Simply call clear_flush_young. 2. We clear_flush_young on a primary MMU PMD, but this may be mapped as a collection of PTEs by the secondary MMU (e.g. during log-dirty). This required expanding the interface of the clear_flush_young mmu notifier, so a lot of code has been trivially touched. 3. In the absence of shadow_accessed_mask (e.g. EPT A bit), we emulate the access bit by blowing the spte. This requires proper synchronizing with MMU notifier consumers, like every other removal of spte's does. Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: remove garbage arg to *hardware_{en,dis}ableRadim Krčmář2014-08-291-1/+1
| | | | | | | | | | | | | | | | | | | | In the beggining was on_each_cpu(), which required an unused argument to kvm_arch_ops.hardware_{en,dis}able, but this was soon forgotten. Remove unnecessary arguments that stem from this. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: static inline empty kvm_arch functionsRadim Krčmář2014-08-291-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using static inline is going to save few bytes and cycles. For example on powerpc, the difference is 700 B after stripping. (5 kB before) This patch also deals with two overlooked empty functions: kvm_arch_flush_shadow was not removed from arch/mips/kvm/mips.c 2df72e9bc KVM: split kvm_arch_flush_shadow and kvm_arch_sched_in never made it into arch/ia64/kvm/kvm-ia64.c. e790d9ef6 KVM: add kvm_arch_sched_in Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: forward declare structs in kvm_types.hPaolo Bonzini2014-08-291-4/+2
|/ | | | | | | | | | Opaque KVM structs are useful for prototypes in asm/kvm_host.h, to avoid "'struct foo' declared inside parameter list" warnings (and consequent breakage due to conflicting types). Move them from individual files to a generic place in linux/kvm_types.h. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* arm64: KVM: fix 64bit CP15 VM access for 32bit guestsMarc Zyngier2014-08-011-2/+4
| | | | | | | | | | | | | | | | | | | | | Commit f0a3eaff71b8 (ARM64: KVM: fix big endian issue in access_vm_reg for 32bit guest) changed the way we handle CP15 VM accesses, so that all 64bit accesses are done via vcpu_sys_reg. This looks like a good idea as it solves indianness issues in an elegant way, except for one small detail: the register index is doesn't refer to the same array! We end up corrupting some random data structure instead. Fix this by reverting to the original code, except for the introduction of a vcpu_cp15_64_high macro that deals with the endianness thing. Tested on Juno with 32bit SMP guests. Cc: Victor Kamensky <victor.kamensky@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* arm64: KVM: common infrastructure for handling AArch32 CP14/CP15Marc Zyngier2014-07-111-4/+9
| | | | | | | | | | As we're about to trap a bunch of CP14 registers, let's rework the CP15 handling so it can be generalized and work with multiple tables. Reviewed-by: Anup Patel <anup.patel@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: add trap handlers for AArch64 debug registersMarc Zyngier2014-07-111-0/+3
| | | | | | | | | | | Add handlers for all the AArch64 debug registers that are accessible from EL0 or EL1. The trapping code keeps track of the state of the debug registers, allowing for the switch code to implement a lazy switching strategy. Reviewed-by: Anup Patel <anup.patel@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM64: KVM: fix big endian issue in access_vm_reg for 32bit guestVictor Kamensky2014-07-111-0/+6
| | | | | | | | | | | | Fix issue with 32bit guests running on top of BE KVM host. Indexes of high and low words of 64bit cp15 register are swapped in case of big endian code, since 64bit cp15 state is restored or saved with double word write or read instruction. Define helper macro to access low words of 64bit cp15 register. Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: vgic: enable GICv2 emulation on top on GICv3 hardwareMarc Zyngier2014-07-111-0/+7
| | | | | | | Add the last missing bits that enable GICv2 emulation on top of GICv3 hardware. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: split GICv2 world switch from hyp codeMarc Zyngier2014-07-111-0/+21
| | | | | | | | | | | Move the GICv2 world switch code into its own file, and add the necessary indirection to the arm64 switch code. Also introduce a new type field to the vgic_params structure. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM/ARM64: KVM: Add base for PSCI v0.2 emulationAnup Patel2014-04-301-1/+1
| | | | | | | | | | | | | | | | | | | Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to VCPUs. This patch extends current in-kernel PSCI emulation to provide PSCI v0.2 interface to VCPUs. By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for keeping the ABI backward-compatible. To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU init using KVM_ARM_VCPU_INIT ioctl. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* arm64: KVM: Add Kconfig option for max VCPUs per-GuestAnup Patel2013-12-281-1/+6
| | | | | | | | | | | | | | | | Current max VCPUs per-Guest is set to 4 which is preventing us from creating a Guest (or VM) with 8 VCPUs on Host (e.g. X-Gene Storm SOC) with 8 Host CPUs. The correct value of max VCPUs per-Guest should be same as the max CPUs supported by GICv2 which is 8 but, increasing value of max VCPUs per-Guest can make things slower hence we add Kconfig option to let KVM users select appropriate max VCPUs per-Guest. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* Merge tag 'kvm-arm-for-3.13-1' of ↵Gleb Natapov2013-10-161-0/+1
|\ | | | | | | | | | | git://git.linaro.org/people/cdall/linux-kvm-arm into next Updates for KVM/ARM including cpu=host and Cortex-A7 support
| * ARM64: KVM: Implement kvm_vcpu_preferred_target() functionAnup Patel2013-10-021-0/+1
| | | | | | | | | | | | | | | | | | | | This patch implements kvm_vcpu_preferred_target() function for KVM ARM64 which will help us implement KVM_ARM_PREFERRED_TARGET ioctl for user space. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* | KVM: arm64: Get rid of KVM_HPAGE definesChristoffer Dall2013-10-141-5/+0
|/ | | | | | | | Now when the main kvm code relying on these defines has been moved to the x86 specific part of the world, we can get rid of these. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* arm64: KVM: use 'int' instead of 'u32' for variable 'target' in kvm_host.h.Chen Gang2013-08-091-1/+1
| | | | | | | | | | | | | | | 'target' will be set to '-1' in kvm_arch_vcpu_init(), and it need check 'target' whether less than zero or not in kvm_vcpu_initialized(). So need define target as 'int' instead of 'u32', just like ARM has done. The related warning: arch/arm64/kvm/../../../arch/arm/kvm/arm.c:497:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] Signed-off-by: Chen Gang <gang.chen@asianux.com> [Marc: reformated the Subject line to fit the series] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: enable initialization of a 32bit vcpuMarc Zyngier2013-06-121-1/+1
| | | | | | | | | | | | Wire the init of a 32bit vcpu by allowing 32bit modes in pstate, and providing sensible defaults out of reset state. This feature is of course conditioned by the presence of 32bit capability on the physical CPU, and is checked by the KVM_CAP_ARM_EL1_32BIT capability. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: define 32bit specific registersMarc Zyngier2013-06-121-1/+4
| | | | | | | | | | | | | | Define the 32bit specific registers (SPSRs, cp15...). Most CPU registers are directly mapped to a 64bit register (r0->x0...). Only the SPSRs have separate registers. cp15 registers are also mapped into their 64bit counterpart in most cases. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: PSCI implementationMarc Zyngier2013-06-121-1/+1
| | | | | | | | Wire the PSCI backend into the exit handling code. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: hypervisor initialization codeMarc Zyngier2013-06-071-0/+13
| | | | | | | Provide EL2 with page tables and stack, and set the vectors to point to the full blown world-switch code. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* arm64: KVM: kvm_arch and kvm_vcpu_arch definitionsMarc Zyngier2013-06-071-0/+186
Provide the architecture dependent structures for VM and vcpu abstractions. Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>