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* Merge tag 'kvm-arm-for-3.18-take-2' of ↵Linus Torvalds2014-10-18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm Pull second batch of changes for KVM/{arm,arm64} from Marc Zyngier: "The most obvious thing is the sizeable MMU changes to support 48bit VAs on arm64. Summary: - support for 48bit IPA and VA (EL2) - a number of fixes for devices mapped into guests - yet another VGIC fix for BE - a fix for CPU hotplug - a few compile fixes (disabled VGIC, strict mm checks)" [ I'm pulling directly from Marc at the request of Paolo Bonzini, whose backpack was stolen at Düsseldorf airport and will do new keys and rebuild his web of trust. - Linus ] * tag 'kvm-arm-for-3.18-take-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm: arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regs arm: kvm: STRICT_MM_TYPECHECKS fix for user_mem_abort arm/arm64: KVM: Ensure memslots are within KVM_PHYS_SIZE arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 arm/arm64: KVM: map MMIO regions at creation time arm64: kvm: define PAGE_S2_DEVICE as read-only by default ARM: kvm: define PAGE_S2_DEVICE as read-only by default arm/arm64: KVM: add 'writable' parameter to kvm_phys_addr_ioremap arm/arm64: KVM: fix potential NULL dereference in user_mem_abort() arm/arm64: KVM: use __GFP_ZERO not memset() to get zeroed pages ARM: KVM: fix vgic-disabled build arm: kvm: fix CPU hotplug
| * arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regsChristoffer Dall2014-10-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The EIRSR and ELRSR registers are 32-bit registers on GICv2, and we store these as an array of two such registers on the vgic vcpu struct. However, we access them as a single 64-bit value or as a bitmap pointer in the generic vgic code, which breaks BE support. Instead, store them as u64 values on the vgic structure and do the word-swapping in the assembly code, which already handles the byte order for BE systems. Tested-by: Victor Kamensky <victor.kamensky@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * arm/arm64: KVM: add 'writable' parameter to kvm_phys_addr_ioremapArd Biesheuvel2014-10-10
| | | | | | | | | | | | | | | | | | | | | | | | Add support for read-only MMIO passthrough mappings by adding a 'writable' parameter to kvm_phys_addr_ioremap. For the moment, mappings will be read-write even if 'writable' is false, but once the definition of PAGE_S2_DEVICE gets changed, those mappings will be created read-only. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* | Merge tag 'iommu-updates-v3.18' of ↵Linus Torvalds2014-10-15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: "This pull-request includes: - change in the IOMMU-API to convert the former iommu_domain_capable function to just iommu_capable - various fixes in handling RMRR ranges for the VT-d driver (one fix requires a device driver core change which was acked by Greg KH) - the AMD IOMMU driver now assigns and deassigns complete alias groups to fix issues with devices using the wrong PCI request-id - MMU-401 support for the ARM SMMU driver - multi-master IOMMU group support for the ARM SMMU driver - various other small fixes all over the place" * tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits) iommu/vt-d: Work around broken RMRR firmware entries iommu/vt-d: Store bus information in RMRR PCI device path iommu/vt-d: Only remove domain when device is removed driver core: Add BUS_NOTIFY_REMOVED_DEVICE event iommu/amd: Fix devid mapping for ivrs_ioapic override iommu/irq_remapping: Fix the regression of hpet irq remapping iommu: Fix bus notifier breakage iommu/amd: Split init_iommu_group() from iommu_init_device() iommu: Rework iommu_group_get_for_pci_dev() iommu: Make of_device_id array const amd_iommu: do not dereference a NULL pointer address. iommu/omap: Remove omap_iommu unused owner field iommu: Remove iommu_domain_has_cap() API function IB/usnic: Convert to use new iommu_capable() API function vfio: Convert to use new iommu_capable() API function kvm: iommu: Convert to use new iommu_capable() API function iommu/tegra: Convert to iommu_capable() API function iommu/msm: Convert to iommu_capable() API function iommu/vt-d: Convert to iommu_capable() API function iommu/fsl: Convert to iommu_capable() API function ...
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| *---. \ Merge branches 'arm/exynos', 'arm/omap', 'arm/smmu', 'x86/vt-d', 'x86/amd' ↵Joerg Roedel2014-10-02
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and 'core' into next Conflicts: drivers/iommu/arm-smmu.c
| | | | * | kvm: iommu: Convert to use new iommu_capable() API functionJoerg Roedel2014-09-25
| | | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
* | | | | Merge tag 'pci-v3.18-changes' of ↵Linus Torvalds2014-10-09
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "The interesting things here are: - Turn on Config Request Retry Status Software Visibility. This caused hangs last time, but we included a fix this time. - Rework PCI device configuration to use _HPP/_HPX more aggressively - Allow PCI devices to be put into D3cold during system suspend - Add arm64 PCI support - Add APM X-Gene host bridge driver - Add TI Keystone host bridge driver - Add Xilinx AXI host bridge driver More detailed summary: Enumeration - Check Vendor ID only for Config Request Retry Status (Rajat Jain) - Enable Config Request Retry Status when supported (Rajat Jain) - Add generic domain handling (Catalin Marinas) - Generate uppercase hex for modalias interface class (Ricardo Ribalda Delgado) Resource management - Add missing MEM_64 mask in pci_assign_unassigned_bridge_resources() (Yinghai Lu) - Increase IBM ipr SAS Crocodile BARs to at least system page size (Douglas Lehr) PCI device hotplug - Prevent NULL dereference during pciehp probe (Andreas Noever) - Move _HPP & _HPX handling into core (Bjorn Helgaas) - Apply _HPP to PCIe devices as well as PCI (Bjorn Helgaas) - Apply _HPP/_HPX to display devices (Bjorn Helgaas) - Preserve SERR & PARITY settings when applying _HPP/_HPX (Bjorn Helgaas) - Preserve MPS and MRRS settings when applying _HPP/_HPX (Bjorn Helgaas) - Apply _HPP/_HPX to all devices, not just hot-added ones (Bjorn Helgaas) - Fix wait time in pciehp timeout message (Yinghai Lu) - Add more pciehp Slot Control debug output (Yinghai Lu) - Stop disabling pciehp notifications during init (Yinghai Lu) MSI - Remove arch_msi_check_device() (Alexander Gordeev) - Rename pci_msi_check_device() to pci_msi_supported() (Alexander Gordeev) - Move D0 check into pci_msi_check_device() (Alexander Gordeev) - Remove unused kobject from struct msi_desc (Yijing Wang) - Remove "pos" from the struct msi_desc msi_attrib (Yijing Wang) - Add "msi_bus" sysfs MSI/MSI-X control for endpoints (Yijing Wang) - Use __get_cached_msi_msg() instead of get_cached_msi_msg() (Yijing Wang) - Use __read_msi_msg() instead of read_msi_msg() (Yijing Wang) - Use __write_msi_msg() instead of write_msi_msg() (Yijing Wang) Power management - Drop unused runtime PM support code for PCIe ports (Rafael J. Wysocki) - Allow PCI devices to be put into D3cold during system suspend (Rafael J. Wysocki) AER - Add additional AER error strings (Gong Chen) - Make <linux/aer.h> standalone includable (Thierry Reding) Virtualization - Add ACS quirk for Solarflare SFC9120 & SFC9140 (Alex Williamson) - Add ACS quirk for Intel 10G NICs (Alex Williamson) - Add ACS quirk for AMD A88X southbridge (Marti Raudsepp) - Remove unused pci_find_upstream_pcie_bridge(), pci_get_dma_source() (Alex Williamson) - Add device flag helpers (Ethan Zhao) - Assume all Mellanox devices have broken INTx masking (Gavin Shan) Generic host bridge driver - Fix ioport_map() for !CONFIG_GENERIC_IOMAP (Liviu Dudau) - Add pci_register_io_range() and pci_pio_to_address() (Liviu Dudau) - Define PCI_IOBASE as the base of virtual PCI IO space (Liviu Dudau) - Fix the conversion of IO ranges into IO resources (Liviu Dudau) - Add pci_get_new_domain_nr() and of_get_pci_domain_nr() (Liviu Dudau) - Add support for parsing PCI host bridge resources from DT (Liviu Dudau) - Add pci_remap_iospace() to map bus I/O resources (Liviu Dudau) - Add arm64 architectural support for PCI (Liviu Dudau) APM X-Gene - Add APM X-Gene PCIe driver (Tanmay Inamdar) - Add arm64 DT APM X-Gene PCIe device tree nodes (Tanmay Inamdar) Freescale i.MX6 - Probe in module_init(), not fs_initcall() (Lucas Stach) - Delay enabling reference clock for SS until it stabilizes (Tim Harvey) Marvell MVEBU - Fix uninitialized variable in mvebu_get_tgt_attr() (Thomas Petazzoni) NVIDIA Tegra - Make sure the PCIe PLL is really reset (Eric Yuen) - Add error path tegra_msi_teardown_irq() cleanup (Jisheng Zhang) - Fix extended configuration space mapping (Peter Daifuku) - Implement resource hierarchy (Thierry Reding) - Clear CLKREQ# enable on port disable (Thierry Reding) - Add Tegra124 support (Thierry Reding) ST Microelectronics SPEAr13xx - Pass config resource through reg property (Pratyush Anand) Synopsys DesignWare - Use NULL instead of false (Fabio Estevam) - Parse bus-range property from devicetree (Lucas Stach) - Use pci_create_root_bus() instead of pci_scan_root_bus() (Lucas Stach) - Remove pci_assign_unassigned_resources() (Lucas Stach) - Check private_data validity in single place (Lucas Stach) - Setup and clear exactly one MSI at a time (Lucas Stach) - Remove open-coded bitmap operations (Lucas Stach) - Fix configuration base address when using 'reg' (Minghuan Lian) - Fix IO resource end address calculation (Minghuan Lian) - Rename get_msi_data() to get_msi_addr() (Minghuan Lian) - Add get_msi_data() to pcie_host_ops (Minghuan Lian) - Add support for v3.65 hardware (Murali Karicheri) - Fold struct pcie_port_info into struct pcie_port (Pratyush Anand) TI Keystone - Add TI Keystone PCIe driver (Murali Karicheri) - Limit MRSS for all downstream devices (Murali Karicheri) - Assume controller is already in RC mode (Murali Karicheri) - Set device ID based on SoC to support multiple ports (Murali Karicheri) Xilinx AXI - Add Xilinx AXI PCIe driver (Srikanth Thokala) - Fix xilinx_pcie_assign_msi() return value test (Dan Carpenter) Miscellaneous - Clean up whitespace (Quentin Lambert) - Remove assignments from "if" conditions (Quentin Lambert) - Move PCI_VENDOR_ID_VMWARE to pci_ids.h (Francesco Ruggeri) - x86: Mark DMI tables as initialization data (Mathias Krause) - x86: Move __init annotation to the correct place (Mathias Krause) - x86: Mark constants of pci_mmcfg_nvidia_mcp55() as __initconst (Mathias Krause) - x86: Constify pci_mmcfg_probes[] array (Mathias Krause) - x86: Mark PCI BIOS initialization code as such (Mathias Krause) - Parenthesize PCI_DEVID and PCI_VPD_LRDT_ID parameters (Megan Kamiya) - Remove unnecessary variable in pci_add_dynid() (Tobias Klauser)" * tag 'pci-v3.18-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (109 commits) arm64: dts: Add APM X-Gene PCIe device tree nodes PCI: Add ACS quirk for AMD A88X southbridge devices PCI: xgene: Add APM X-Gene PCIe driver PCI: designware: Remove open-coded bitmap operations PCI/MSI: Remove unnecessary temporary variable PCI/MSI: Use __write_msi_msg() instead of write_msi_msg() MSI/powerpc: Use __read_msi_msg() instead of read_msi_msg() PCI/MSI: Use __get_cached_msi_msg() instead of get_cached_msi_msg() PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpoints PCI/MSI: Remove "pos" from the struct msi_desc msi_attrib PCI/MSI: Remove unused kobject from struct msi_desc PCI/MSI: Rename pci_msi_check_device() to pci_msi_supported() PCI/MSI: Move D0 check into pci_msi_check_device() PCI/MSI: Remove arch_msi_check_device() irqchip: armada-370-xp: Remove arch_msi_check_device() PCI/MSI/PPC: Remove arch_msi_check_device() arm64: Add architectural support for PCI PCI: Add pci_remap_iospace() to map bus I/O resources of/pci: Add support for parsing PCI host bridge resources from DT of/pci: Add pci_get_new_domain_nr() and of_get_pci_domain_nr() ... Conflicts: arch/arm64/boot/dts/apm-storm.dtsi
| * | | | | KVM: Use PCI device flag helper functionsEthan Zhao2014-09-16
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use PCI device flag helper functions when assigning or releasing device. No functional change. Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
* | | | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2014-10-08
|\ \ \ \ \ | |_|/ / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "Fixes and features for 3.18. Apart from the usual cleanups, here is the summary of new features: - s390 moves closer towards host large page support - PowerPC has improved support for debugging (both inside the guest and via gdbstub) and support for e6500 processors - ARM/ARM64 support read-only memory (which is necessary to put firmware in emulated NOR flash) - x86 has the usual emulator fixes and nested virtualization improvements (including improved Windows support on Intel and Jailhouse hypervisor support on AMD), adaptive PLE which helps overcommitting of huge guests. Also included are some patches that make KVM more friendly to memory hot-unplug, and fixes for rare caching bugs. Two patches have trivial mm/ parts that were acked by Rik and Andrew. Note: I will soon switch to a subkey for signing purposes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (157 commits) kvm: do not handle APIC access page if in-kernel irqchip is not in use KVM: s390: count vcpu wakeups in stat.halt_wakeup KVM: s390/facilities: allow TOD-CLOCK steering facility bit KVM: PPC: BOOK3S: HV: CMA: Reserve cma region only in hypervisor mode arm/arm64: KVM: Report correct FSC for unsupported fault types arm/arm64: KVM: Fix VTTBR_BADDR_MASK and pgd alloc kvm: Fix kvm_get_page_retry_io __gup retval check arm/arm64: KVM: Fix set_clear_sgi_pend_reg offset kvm: x86: Unpin and remove kvm_arch->apic_access_page kvm: vmx: Implement set_apic_access_page_addr kvm: x86: Add request bit to reload APIC access page address kvm: Add arch specific mmu notifier for page invalidation kvm: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make it non-static kvm: Fix page ageing bugs kvm/x86/mmu: Pass gfn and level to rmapp callback. x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only kvm: x86: use macros to compute bank MSRs KVM: x86: Remove debug assertion of non-PAE reserved bits kvm: don't take vcpu mutex for obviously invalid vcpu ioctls kvm: Faults which trigger IO release the mmap_sem ...
| * | | | Merge tag 'kvm-arm-for-3.18' of ↵Paolo Bonzini2014-09-27
| |\ \ \ \ | | | |_|/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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]
| | * | | arm/arm64: KVM: Fix set_clear_sgi_pend_reg offsetChristoffer Dall2014-09-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sgi values calculated in read_set_clear_sgi_pend_reg() and write_set_clear_sgi_pend_reg() were horribly incorrectly multiplied by 4 with catastrophic results in that subfunctions ended up overwriting memory not allocated for the expected purpose. This showed up as bugs in kfree() and the kernel complaining a lot of you turn on memory debugging. This addresses: http://marc.info/?l=kvm&m=141164910007868&w=2 Reported-by: Shannon Zhao <zhaoshenglong@huawei.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: vgic: make number of irqs a configurable attributeMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to make the number of interrupts configurable, use the new fancy device management API to add KVM_DEV_ARM_VGIC_GRP_NR_IRQS as a VGIC configurable attribute. Userspace can now specify the exact size of the GIC (by increments of 32 interrupts). Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | arm/arm64: KVM: vgic: delay vgic allocation until init timeMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is now quite easy to delay the allocation of the vgic tables until we actually require it to be up and running (when the first vcpu is kicking around, or someones tries to access the GIC registers). This allow us to allocate memory for the exact number of CPUs we have. As nobody configures the number of interrupts just yet, use a fallback to VGIC_NR_IRQS_LEGACY. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | arm/arm64: KVM: vgic: kill VGIC_NR_IRQSMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nuke VGIC_NR_IRQS entierly, now that the distributor instance contains the number of IRQ allocated to this GIC. Also add VGIC_NR_IRQS_LEGACY to preserve the current API. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | arm/arm64: KVM: vgic: handle out-of-range MMIO accessesMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we can (almost) dynamically size the number of interrupts, we're facing an interesting issue: We have to evaluate at runtime whether or not an access hits a valid register, based on the sizing of this particular instance of the distributor. Furthermore, the GIC spec says that accessing a reserved register is RAZ/WI. For this, add a new field to our range structure, indicating the number of bits a single interrupts uses. That allows us to find out whether or not the access is in range. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | arm/arm64: KVM: vgic: kill VGIC_MAX_CPUSMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now have the information about the number of CPU interfaces in the distributor itself. Let's get rid of VGIC_MAX_CPUS, and just rely on KVM_MAX_VCPUS where we don't have the choice. Yet. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | arm/arm64: KVM: vgic: Parametrize VGIC_NR_SHARED_IRQSMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having a dynamic number of supported interrupts means that we cannot relly on VGIC_NR_SHARED_IRQS being fixed anymore. Instead, make it take the distributor structure as a parameter, so it can return the right value. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | arm/arm64: KVM: vgic: switch to dynamic allocationMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So far, all the VGIC data structures are statically defined by the *maximum* number of vcpus and interrupts it supports. It means that we always have to oversize it to cater for the worse case. Start by changing the data structures to be dynamically sizeable, and allocate them at runtime. The sizes are still very static though. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | KVM: ARM: vgic: plug irq injection raceMarc Zyngier2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As it stands, nothing prevents userspace from injecting an interrupt before the guest's GIC is actually initialized. This goes unnoticed so far (as everything is pretty much statically allocated), but ends up exploding in a spectacular way once we switch to a more dynamic allocation (the GIC data structure isn't there yet). The fix is to test for the "ready" flag in the VGIC distributor before trying to inject the interrupt. Note that in order to avoid breaking userspace, we have to ignore what is essentially an error. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: vgic: Clarify and correct vgic documentationChristoffer Dall2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The VGIC virtual distributor implementation documentation was written a very long time ago, before the true nature of the beast had been partially absorbed into my bloodstream. Clarify the docs. Plus, it fixes an actual bug. ICFRn, pfff. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: vgic: Fix SGI writes to GICD_I{CS}PENDR0Christoffer Dall2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Writes to GICD_ISPENDR0 and GICD_ICPENDR0 ignore all settings of the pending state for SGIs. Make sure the implementation handles this correctly. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: vgic: Improve handling of GICD_I{CS}PENDRnChristoffer Dall2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Writes to GICD_ISPENDRn and GICD_ICPENDRn are currently not handled correctly for level-triggered interrupts. The spec states that for level-triggered interrupts, writes to the GICD_ISPENDRn activate the output of a flip-flop which is in turn or'ed with the actual input interrupt signal. Correspondingly, writes to GICD_ICPENDRn simply deactivates the output of that flip-flop, but does not (of course) affect the external input signal. Reads from GICC_IAR will also deactivate the flip-flop output. This requires us to track the state of the level-input separately from the state in the flip-flop. We therefore introduce two new variables on the distributor struct to track these two states. Astute readers may notice that this is introducing more state than required (because an OR of the two states gives you the pending state), but the remaining vgic code uses the pending bitmap for optimized operations to figure out, at the end of the day, if an interrupt is pending or not on the distributor side. Refactoring the code to consider the two state variables all the places where we currently access the precomputed pending value, did not look pretty. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: vgic: Clear queued flags on unqueueChristoffer Dall2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we unqueue a level-triggered interrupt completely, and the LR does not stick around in the active state (and will therefore no longer generate a maintenance interrupt), then we should clear the queued flag so that the vgic can actually queue this level-triggered interrupt at a later time and deal with its pending state then. Note: This should actually be properly fixed to handle the active state on the distributor. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: Rename irq_active to irq_queuedChristoffer Dall2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a special bitmap on the distributor struct to keep track of when level-triggered interrupts are queued on the list registers. This was named irq_active, which is confusing, because the active state of an interrupt as per the GIC spec is a different thing, not specifically related to edge-triggered/level-triggered configurations but rather indicates an interrupt which has been ack'ed but not yet eoi'ed. Rename the bitmap and the corresponding accessor functions to irq_queued to clarify what this is actually used for. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | arm/arm64: KVM: Rename irq_state to irq_pendingChristoffer Dall2014-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The irq_state field on the distributor struct is ambiguous in its meaning; the comment says it's the level of the input put, but that doesn't make much sense for edge-triggered interrupts. The code actually uses this state variable to check if the interrupt is in the pending state on the distributor so clarify the comment and rename the actual variable and accessor methods. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| | * | | Merge remote-tracking branch 'kvm/next' into queueChristoffer Dall2014-09-18
| | |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/arm64/include/asm/kvm_host.h virt/kvm/arm/vgic.c
| | * | | | KVM: EVENTFD: remove inclusion of irq.hEric Auger2014-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No more needed. irq.h would be void on ARM. Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
| | * | | | KVM: vgic: declare probe function pointer as constWill Deacon2014-08-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We extract the vgic probe function from the of_device_id data pointer, which is const. Kill the sparse warning by ensuring that the local function pointer is also marked as const. 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: vgic: return int instead of bool when checking I/O rangesWill Deacon2014-08-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vgic_ioaddr_overlap claims to return a bool, but in reality it returns an int. Shut sparse up by fixing the type signature. 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: Introduce gfn_to_hva_memslot_protChristoffer Dall2014-08-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To support read-only memory regions on arm and arm64, we have a need to resolve a gfn to an hva given a pointer to a memslot to avoid looping through the memslots twice and to reuse the hva error checking of gfn_to_hva_prot(), add a new gfn_to_hva_memslot_prot() function and refactor gfn_to_hva_prot() to use this function. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
| * | | | | kvm: Fix kvm_get_page_retry_io __gup retval checkAndres Lagar-Cavilla2014-09-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Confusion around -EBUSY and zero (inside a BUG_ON no less). Reported-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | kvm: Add arch specific mmu notifier for page invalidationTang Chen2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Rename make_all_cpus_request() to kvm_make_all_cpus_request() and make ↵Tang Chen2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | it non-static Different architectures need different requests, and in fact we will use this function in architecture-specific code later. This will be outside kvm_main.c, so make it non-static and rename it to kvm_make_all_cpus_request(). Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | kvm: Fix page ageing bugsAndres Lagar-Cavilla2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: don't take vcpu mutex for obviously invalid vcpu ioctlsDavid Matlack2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vcpu ioctls can hang the calling thread if issued while a vcpu is running. However, invalid ioctls can happen when userspace tries to probe the kind of file descriptors (e.g. isatty() calls ioctl(TCGETS)); in that case, we know the ioctl is going to be rejected as invalid anyway and we can fail before trying to take the vcpu mutex. This patch does not change functionality, it just makes invalid ioctls fail faster. Cc: stable@vger.kernel.org Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | kvm: Faults which trigger IO release the mmap_semAndres Lagar-Cavilla2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When KVM handles a tdp fault it uses FOLL_NOWAIT. If the guest memory has been swapped out or is behind a filemap, this will trigger async readahead and return immediately. The rationale is that KVM will kick back the guest with an "async page fault" and allow for some other guest process to take over. If async PFs are enabled the fault is retried asap from an async workqueue. If not, it's retried immediately in the same code path. In either case the retry will not relinquish the mmap semaphore and will block on the IO. This is a bad thing, as other mmap semaphore users now stall as a function of swap or filemap latency. This patch ensures both the regular and async PF path re-enter the fault allowing for the mmap semaphore to be relinquished in the case of IO wait. Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Andres Lagar-Cavilla <andreslc@google.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | kvm-vfio: do not use module_initPaolo Bonzini2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | /me got confused between the kernel and QEMU. In the kernel, you can only have one module_init function, and it will prevent unloading the module unless you also have the corresponding module_exit function. So, commit 80ce1639727e (KVM: VFIO: register kvm_device_ops dynamically, 2014-09-02) broke unloading of the kvm module, by adding a module_init function and no module_exit. Repair it by making kvm_vfio_ops_init weak, and checking it in kvm_init. Cc: Will Deacon <will.deacon@arm.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: Alex Williamson <Alex.Williamson@redhat.com> Fixes: 80ce1639727e9d38729c34f162378508c307ca25 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | | KVM: EVENTFD: Remove inclusion of irq.hChristoffer Dall2014-09-24
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c77dcac (KVM: Move more code under CONFIG_HAVE_KVM_IRQFD) added functionality that depends on definitions in ioapic.h when __KVM_HAVE_IOAPIC is defined. At the same time, kvm-arm commit 0ba0951 (KVM: EVENTFD: remove inclusion of irq.h) removed the inclusion of irq.h, an architecture-specific header that is not present on ARM but which happened to include ioapic.h on x86. Include ioapic.h directly in eventfd.c if __KVM_HAVE_IOAPIC is defined. This fixes x86 and lets ARM use eventfd.c. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: VFIO: register kvm_device_ops dynamicallyWill Deacon2014-09-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we have a dynamic means to register kvm_device_ops, use that for the VFIO kvm device, instead of relying on the static table. This is achieved by a module_init call to register the ops with KVM. Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Alex Williamson <Alex.Williamson@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: s390: register flic ops dynamicallyCornelia Huck2014-09-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using the new kvm_register_device_ops() interface makes us get rid of an #ifdef in common code. Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: ARM: vgic: register kvm_device_ops dynamicallyWill Deacon2014-09-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we have a dynamic means to register kvm_device_ops, use that for the ARM VGIC, instead of relying on the static table. Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: device: add simple registration mechanism for kvm_device_opsWill Deacon2014-09-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvm_ioctl_create_device currently has knowledge of all the device types and their associated ops. This is fairly inflexible when adding support for new in-kernel device emulations, so move what we currently have out into a table, which can support dynamic registration of ops by new drivers for virtual hardware. Cc: Alex Williamson <Alex.Williamson@redhat.com> Cc: Alex Graf <agraf@suse.de> Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | kvm: ioapic: conditionally delay irq delivery duringeoi broadcastZhang Haoyu2014-09-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we call ioapic_service() immediately when we find the irq is still active during eoi broadcast. But for real hardware, there's some delay between the EOI writing and irq delivery. If we do not emulate this behavior, and re-inject the interrupt immediately after the guest sends an EOI and re-enables interrupts, a guest might spend all its time in the ISR if it has a broken handler for a level-triggered interrupt. Such livelock actually happens with Windows guests when resuming from hibernation. As there's no way to recognize the broken handle from new raised ones, this patch delays an interrupt if 10.000 consecutive EOIs found that the interrupt was still high. The guest can then make a little forward progress, until a proper IRQ handler is set or until some detection routine in the guest (such as Linux's note_interrupt()) recognizes the situation. Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Zhang Haoyu <zhanghy@sangfor.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: remove redundant assignments in __kvm_set_memory_regionChristian Borntraeger2014-09-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __kvm_set_memory_region sets r to EINVAL very early. Doing it again is not necessary. The same is true later on, where r is assigned -ENOMEM twice. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: remove redundant assigment of return value in kvm_dev_ioctlChristian Borntraeger2014-09-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The first statement of kvm_dev_ioctl is long r = -EINVAL; No need to reassign the same value. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: remove redundant check of in_spin_loopChristian Borntraeger2014-09-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The expression `vcpu->spin_loop.in_spin_loop' is always true, because it is evaluated only when the condition `!vcpu->spin_loop.in_spin_loop' is false. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | kvm: fix potentially corrupt mmio cacheDavid Matlack2014-09-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vcpu exits and memslot mutations can run concurrently as long as the vcpu does not aquire the slots mutex. Thus it is theoretically possible for memslots to change underneath a vcpu that is handling an exit. If we increment the memslot generation number again after synchronize_srcu_expedited(), vcpus can safely cache memslot generation without maintaining a single rcu_dereference through an entire vm exit. And much of the x86/kvm code does not maintain a single rcu_dereference of the current memslots during each exit. We can prevent the following case: vcpu (CPU 0) | thread (CPU 1) --------------------------------------------+-------------------------- 1 vm exit | 2 srcu_read_unlock(&kvm->srcu) | 3 decide to cache something based on | old memslots | 4 | change memslots | (increments generation) 5 | synchronize_srcu(&kvm->srcu); 6 retrieve generation # from new memslots | 7 tag cache with new memslot generation | 8 srcu_read_unlock(&kvm->srcu) | ... | <action based on cache occurs even | though the caching decision was based | on the old memslots> | ... | <action *continues* to occur until next | memslot generation change, which may | be never> | | By incrementing the generation after synchronizing with kvm->srcu readers, we ensure that the generation retrieved in (6) will become invalid soon after (8). Keeping the existing increment is not strictly necessary, but we do keep it and just move it for consistency from update_memslots to install_new_memslots. It invalidates old cached MMIOs immediately, instead of having to wait for the end of synchronize_srcu_expedited, which makes the code more clearly correct in case CPU 1 is preempted right after synchronize_srcu() returns. To avoid halving the generation space in SPTEs, always presume that the low bit of the generation is zero when reconstructing a generation number out of an SPTE. This effectively disables MMIO caching in SPTEs during the call to synchronize_srcu_expedited. Using the low bit this way is somewhat like a seqcount---where the protected thing is a cache, and instead of retrying we can simply punt if we observe the low bit to be 1. Cc: stable@vger.kernel.org Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: do not bias the generation number in kvm_current_mmio_generationPaolo Bonzini2014-09-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The next patch will give a meaning (a la seqcount) to the low bit of the generation number. Ensure that it matches between kvm->memslots->generation and kvm_current_mmio_generation(). Cc: stable@vger.kernel.org Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | | KVM: remove garbage arg to *hardware_{en,dis}ableRadim Krčmář2014-08-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Unconditionally export KVM_CAP_READONLY_MEMChristoffer Dall2014-08-29
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The idea between capabilities and the KVM_CHECK_EXTENSION ioctl is that userspace can, at run-time, determine if a feature is supported or not. This allows KVM to being supporting a new feature with a new kernel version without any need to update user space. Unfortunately, since the definition of KVM_CAP_READONLY_MEM was guarded by #ifdef __KVM_HAVE_READONLY_MEM, such discovery still required a user space update. Therefore, unconditionally export KVM_CAP_READONLY_MEM and change the in-kernel conditional to rely on __KVM_HAVE_READONLY_MEM. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>