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2016-04-08Merge tag 'kvm-arm-for-4.6-rc4' of ↵Radim Krčmář3-8/+7
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm KVM/ARM Fixes for v4.6-rc4 Addresses: - Wrong indentation in the PMU code from the merge window - A long-time bug occuring with running ntpd on the host, candidate for stable - Properly handle (and warn about) the unsupported configuration of running on systems with less than 40 bits of PA space - More fixes to the PM and hotplug notifier stuff from the merge window
2016-04-06arm64: KVM: Warn when PARange is less than 40 bitsMarc Zyngier3-8/+7
We always thought that 40bits of PA range would be the minimum people would actually build. Anything less is terrifyingly small. Turns out that we were both right and wrong. Nobody has ever built such a system, but the ARM Foundation Model has a PARange set to 36bits. Just because we can. Oh well. Now, the KVM API explicitely says that we offer a 40bit PA space to the VM, so we shouldn't run KVM on the Foundation Model at all. That being said, this patch offers a less agressive alternative, and loudly warns about the configuration being unsupported. You'll still be able to run VMs (at your own risks, though). This is just a workaround until we have a proper userspace API where we report the PARange to userspace. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2-1/+6
Pull KVM fixes from Paolo Bonzini: "Miscellaneous bugfixes. The ARM and s390 fixes are for new regressions from the merge window, others are usual stable material" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: compiler-gcc: disable -ftracer for __noclone functions kvm: x86: make lapic hrtimer pinned s390/mm/kvm: fix mis-merge in gmap handling kvm: set page dirty only if page has been writable KVM: x86: reduce default value of halt_poll_ns parameter KVM: Hyper-V: do not do hypercall userspace exits if SynIC is disabled KVM: x86: Inject pending interrupt even if pending nmi exist arm64: KVM: Register CPU notifiers when the kernel runs at HYP arm64: kvm: 4.6-rc1: Fix VTCR_EL2 VS setting
2016-03-30arm64: kvm: 4.6-rc1: Fix VTCR_EL2 VS settingSuzuki K Poulose2-1/+6
When we detect support for 16bit VMID in ID_AA64MMFR1, we set the VTCR_EL2_VS field to 1 to make use of 16bit vmids. But, with commit 3a3604bc5eb4 ("arm64: KVM: Switch to C-based stage2 init") this is broken and we corrupt VTCR_EL2:T0SZ instead of updating the VS field. VTCR_EL2_VS was actually defined to the field shift (19) and not the real value for VS. This patch fixes the issue. Fixes: commit 3a3604bc5eb4 ("arm64: KVM: Switch to C-based stage2 init") Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-03-29arm64: perf: Move PMU register related defines to asm/perf_event.hShannon Zhao4-70/+47
To use the ARMv8 PMU related register defines from the KVM code, we move the relevant definitions to asm/perf_event.h header file and rename them with prefix ARMV8_PMU_. This allows us to get rid of kvm_perf_event.h. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-29arm64: opcodes.h: Add arm big-endian config options before including arm headerJames Morse1-0/+4
arm and arm64 use different config options to specify big endian. This needs taking into account when including code/headers between the two architectures. A case in point is PAN, which uses the __instr_arm() macro to output instructions. The macro comes from opcodes.h, which lives under arch/arm. On a big-endian build the mismatched config options mean the instruction isn't byte swapped correctly, resulting in undefined instruction exceptions during boot: | alternatives: patching kernel code | kdevtmpfs[87]: undefined instruction: pc=ffffffc0004505b4 | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c | Internal error: Oops - undefined instruction: 0 [#1] SMP | Modules linked in: | CPU: 0 PID: 87 Comm: kdevtmpfs Not tainted 4.1.16+ #5 | Hardware name: Hisilicon PhosphorHi1382 EVB (DT) | task: ffffffc336591700 ti: ffffffc3365a4000 task.ti: ffffffc3365a4000 | PC is at dump_instr+0x68/0x100 | LR is at do_undefinstr+0x1d4/0x2a4 | pc : [<ffffffc00076231c>] lr : [<ffffffc0000811d4>] pstate: 604001c5 | sp : ffffffc3365a6450 Cc: <stable@vger.kernel.org> #4.3.x- Reported-by: Hanjun Guo <guohanjun@huawei.com> Tested-by: Xuefeng Wang <wxf.wang@hisilicon.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-25arch, ftrace: for KASAN put hard/soft IRQ entries into separate sectionsAlexander Potapenko1-1/+1
KASAN needs to know whether the allocation happens in an IRQ handler. This lets us strip everything below the IRQ entry point to reduce the number of unique stack traces needed to be stored. Move the definition of __irq_entry to <linux/interrupt.h> so that the users don't need to pull in <linux/ftrace.h>. Also introduce the __softirq_entry macro which is similar to __irq_entry, but puts the corresponding functions to the .softirqentry.text section. Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-24Merge tag 'arm64-upstream' of ↵Linus Torvalds1-7/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull second set of arm64 updates from Catalin Marinas: - KASLR bug fixes: use callee-saved register, boot-time I-cache maintenance - inv_entry asm macro fix (EL0 check typo) - pr_notice("Virtual kernel memory layout...") splitting - Clean-ups: use p?d_set_huge consistently, allow preemption around copy_to_user_page, remove unused __local_flush_icache_all() * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: mm: allow preemption in copy_to_user_page arm64: consistently use p?d_set_huge arm64: kaslr: use callee saved register to preserve SCTLR across C call arm64: Split pr_notice("Virtual kernel memory layout...") into multiple pr_cont() arm64: drop unused __local_flush_icache_all() arm64: fix KASLR boot-time I-cache maintenance arm64/kernel: fix incorrect EL0 check in inv_entry macro
2016-03-21arm64: drop unused __local_flush_icache_all()Kefeng Wang1-7/+0
After commit 65da0a8e34a8 ("arm64: use non-global mappings for UEFI runtime regions"), nobody use __local_flush_icache_all() anymore, so drop it. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-03-21arm64: KVM: Turn kvm_ksym_ref into a NOP on VHEMarc Zyngier1-1/+7
When running with VHE, there is no need to translate kernel pointers to the EL2 memory space, since we're already there (and we have a much saner memory map to start with). Unfortunately, kvm_ksym_ref is getting in the way, and the first call into the "hypervisor" section is going to end up in fireworks, since we're now branching into nowhereland. Meh. A potential solution is to test if VHE is engaged or not, and only perform the translation in the negative case. With this in place, VHE is able to run again. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-03-20Merge tag 'armsoc-arm64' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC 64-bit changes from Arnd Bergmann: "Here's our branch of ARM64 contents for this merge window, now containing all ARM64 changes other than device tree files. - Various new platforms get added: * Allwinner A64 SoC * Annapurna Labs Alpine SoCs * Broadcom Vulcan * Marvell Armada 3700 SoCs * Amlogic S905 - Various defconfig changes to enable platform specific drivers This branch includes the clk git tree to resolve a build-time dependency" * tag 'armsoc-arm64' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (48 commits) arm64: defconfig: Increase MMC_BLOCK_MINORS to 16 arm64: defconfig: Add Qualcomm sdhci and restart functionality ARM64: Enable Amlogic Meson GXBaby platform arm64: defconfig: Enable Samsung MFD and related configs arm64: alpine: select the Alpine MSI controller driver arm64: defconfig: enable the Alpine family arm64: add Alpine SoC family arm64: defconfig: Enable exynos thermal config arm64: add defconfig options for Allwinner SoCs arm64: defconfig: Enable DesignWare APB GPIO controller arm64: defconfig: Add Renesas R-Car Gen3 USB 2.0 phy driver support arm64: EXYNOS: Consolidate ARCH_EXYNOS7 symbol into ARCH_EXYNOS clk: samsung: Don't build ARMv8 clock drivers on ARMv7 MAINTAINERS: Add entry for Broadcom Vulcan SoC arm64: cputype info for Broadcom Vulcan arm64: Broadcom Vulcan support arm64: defconfig: Add Broadcom Vulcan to defconfig arm64: update ARCH_MVEBU for Marvell Armada 7K/8K support Documentation: arm: add Marvell Armada 7K and 8K families Documentation: arm: add link to Armada 38x Functional Spec ...
2016-03-17Merge tag 'arm64-upstream' of ↵Linus Torvalds37-286/+715
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Here are the main arm64 updates for 4.6. There are some relatively intrusive changes to support KASLR, the reworking of the kernel virtual memory layout and initial page table creation. Summary: - Initial page table creation reworked to avoid breaking large block mappings (huge pages) into smaller ones. The ARM architecture requires break-before-make in such cases to avoid TLB conflicts but that's not always possible on live page tables - Kernel virtual memory layout: the kernel image is no longer linked to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of the vmalloc space, allowing the kernel to be loaded (nearly) anywhere in physical RAM - Kernel ASLR: position independent kernel Image and modules being randomly mapped in the vmalloc space with the randomness is provided by UEFI (efi_get_random_bytes() patches merged via the arm64 tree, acked by Matt Fleming) - Implement relative exception tables for arm64, required by KASLR (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but actual x86 conversion to deferred to 4.7 because of the merge dependencies) - Support for the User Access Override feature of ARMv8.2: this allows uaccess functions (get_user etc.) to be implemented using LDTR/STTR instructions. Such instructions, when run by the kernel, perform unprivileged accesses adding an extra level of protection. The set_fs() macro is used to "upgrade" such instruction to privileged accesses via the UAO bit - Half-precision floating point support (part of ARMv8.2) - Optimisations for CPUs with or without a hardware prefetcher (using run-time code patching) - copy_page performance improvement to deal with 128 bytes at a time - Sanity checks on the CPU capabilities (via CPUID) to prevent incompatible secondary CPUs from being brought up (e.g. weird big.LITTLE configurations) - valid_user_regs() reworked for better sanity check of the sigcontext information (restored pstate information) - ACPI parking protocol implementation - CONFIG_DEBUG_RODATA enabled by default - VDSO code marked as read-only - DEBUG_PAGEALLOC support - ARCH_HAS_UBSAN_SANITIZE_ALL enabled - Erratum workaround Cavium ThunderX SoC - set_pte_at() fix for PROT_NONE mappings - Code clean-ups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits) arm64: kasan: Fix zero shadow mapping overriding kernel image shadow arm64: kasan: Use actual memory node when populating the kernel image shadow arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission arm64: Fix misspellings in comments. arm64: efi: add missing frame pointer assignment arm64: make mrs_s prefixing implicit in read_cpuid arm64: enable CONFIG_DEBUG_RODATA by default arm64: Rework valid_user_regs arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly arm64: KVM: Move kvm_call_hyp back to its original localtion arm64: mm: treat memstart_addr as a signed quantity arm64: mm: list kernel sections in order arm64: lse: deal with clobbered IP registers after branch via PLT arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR arm64: kconfig: add submenu for 8.2 architectural features arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot arm64: Add support for Half precision floating point arm64: Remove fixmap include fragility arm64: Add workaround for Cavium erratum 27456 arm64: mm: Mark .rodata as RO ...
2016-03-16Merge tag 'pci-v4.6-changes' of ↵Linus Torvalds2-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "PCI changes for v4.6: Enumeration: - Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas) - Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas Resource management: - Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas) - Don't assign or reassign immutable resources (Bjorn Helgaas) - Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas) - Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas) - Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas) - ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas) - ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas) - MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas) - Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas) - Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas) - rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi) - designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi) Virtualization: - Wait for up to 1000ms after FLR reset (Alex Williamson) - Support SR-IOV on any function type (Kelly Zytaruk) - Add ACS quirk for all Cavium devices (Manish Jaggi) AER: - Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas) - Restore pci_ops pointer while calling original pci_ops (David Daney) - Fix aer_inject error codes (Jean Delvare) - Use dev_warn() in aer_inject (Jean Delvare) - Log actual error causes in aer_inject (Jean Delvare) - Log aer_inject error injections (Jean Delvare) VPD: - Prevent VPD access for buggy devices (Babu Moger) - Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas) - Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas) - Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas) - Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas) - Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas) - Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas) - Update VPD definitions (Hannes Reinecke) - Allow access to VPD attributes with size 0 (Hannes Reinecke) - Determine actual VPD size on first access (Hannes Reinecke) Generic host bridge driver: - Move structure definitions to separate header file (David Daney) - Add pci_host_common_probe(), based on gen_pci_probe() (David Daney) - Expose pci_host_common_probe() for use by other drivers (David Daney) Altera host bridge driver: - Fix altera_pcie_link_is_up() (Ley Foon Tan) Cavium ThunderX host bridge driver: - Add PCIe host driver for ThunderX processors (David Daney) - Add driver for ThunderX-pass{1,2} on-chip devices (David Daney) Freescale i.MX6 host bridge driver: - Add DT bindings to configure PHY Tx driver settings (Justin Waters) - Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach) - Move PHY reset into imx6_pcie_establish_link() (Lucas Stach) - Remove broken Gen2 workaround (Lucas Stach) - Move link up check into imx6_pcie_wait_for_link() (Lucas Stach) Freescale Layerscape host bridge driver: - Add "fsl,ls2085a-pcie" compatible ID (Yang Shi) Intel VMD host bridge driver: - Attach VMD resources to parent domain's resource tree (Jon Derrick) - Set bus resource start to 0 (Keith Busch) Microsoft Hyper-V host bridge driver: - Add fwnode_handle to x86 pci_sysdata (Jake Oshins) - Look up IRQ domain by fwnode_handle (Jake Oshins) - Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins) NVIDIA Tegra host bridge driver: - Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding) - Implement ->{add,remove}_bus() callbacks (Thierry Reding) - Remove unused struct tegra_pcie.num_ports field (Thierry Reding) - Track bus -> CPU mapping (Thierry Reding) - Remove misleading PHYS_OFFSET (Thierry Reding) Renesas R-Car host bridge driver: - Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman) Synopsys DesignWare host bridge driver: - ARC: Add PCI support (Joao Pinto) - Add generic dw_pcie_wait_for_link() (Joao Pinto) - Add default link up check if sub-driver doesn't override (Joao Pinto) - Add driver for prototyping kits based on ARC SDP (Joao Pinto) TI Keystone host bridge driver: - Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin) Xilinx AXI host bridge driver: - Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada) - Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada) - Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada) - Update Zynq binding with Microblaze node (Bharat Kumar Gogada) - microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada) Xilinx NWL host bridge driver: - Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada) Miscellaneous: - Check device_attach() return value always (Bjorn Helgaas) - Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas) - Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas) - ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas) - Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas) - Remove includes of asm/pci-bridge.h (Bjorn Helgaas) - Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas) - unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas) - Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler) - Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas) - Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa) - frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig) - Move pci_dma_* helpers to common code (Christoph Hellwig) - Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus) - Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson) - Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)" * tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits) PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition PCI: designware: Add driver for prototyping kits based on ARC SDP PCI: designware: Add default link up check if sub-driver doesn't override PCI: designware: Add generic dw_pcie_wait_for_link() PCI: Cleanup pci/pcie/Kconfig whitespace PCI: Simplify pci_create_attr() control flow PCI: Don't leak memory if sysfs_create_bin_file() fails PCI: Simplify sysfs ROM cleanup PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource MIPS: Loongson 3: Use temporary struct resource * to avoid repetition ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource ia64/PCI: Use ioremap() instead of open-coded equivalent ia64/PCI: Use temporary struct resource * to avoid repetition PCI: Clean up pci_map_rom() whitespace PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices PCI: thunder: Add PCIe host driver for ThunderX processors PCI: generic: Expose pci_host_common_probe() for use by other drivers PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe() ...
2016-03-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds11-12/+343
Pull KVM updates from Paolo Bonzini: "One of the largest releases for KVM... Hardly any generic changes, but lots of architecture-specific updates. ARM: - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems - PMU support for guests - 32bit world switch rewritten in C - various optimizations to the vgic save/restore code. PPC: - enabled KVM-VFIO integration ("VFIO device") - optimizations to speed up IPIs between vcpus - in-kernel handling of IOMMU hypercalls - support for dynamic DMA windows (DDW). s390: - provide the floating point registers via sync regs; - separated instruction vs. data accesses - dirty log improvements for huge guests - bugfixes and documentation improvements. x86: - Hyper-V VMBus hypercall userspace exit - alternative implementation of lowest-priority interrupts using vector hashing (for better VT-d posted interrupt support) - fixed guest debugging with nested virtualizations - improved interrupt tracking in the in-kernel IOAPIC - generic infrastructure for tracking writes to guest memory - currently its only use is to speedup the legacy shadow paging (pre-EPT) case, but in the future it will be used for virtual GPUs as well - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits) KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch KVM: x86: disable MPX if host did not enable MPX XSAVE features arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit arm64: KVM: vgic-v3: Reset LRs at boot time arm64: KVM: vgic-v3: Do not save an LR known to be empty arm64: KVM: vgic-v3: Save maintenance interrupt state only if required arm64: KVM: vgic-v3: Avoid accessing ICH registers KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit KVM: arm/arm64: vgic-v2: Reset LRs at boot time KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers KVM: s390: allocate only one DMA page per VM KVM: s390: enable STFLE interpretation only if enabled for the guest KVM: s390: wake up when the VCPU cpu timer expires KVM: s390: step the VCPU timer while in enabled wait KVM: s390: protect VCPU cpu timer with a seqcount KVM: s390: step VCPU cpu timer during kvm_run ioctl ...
2016-03-14Merge branch 'mm-readonly-for-linus' of ↵Linus Torvalds1-4/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull read-only kernel memory updates from Ingo Molnar: "This tree adds two (security related) enhancements to the kernel's handling of read-only kernel memory: - extend read-only kernel memory to a new class of formerly writable kernel data: 'post-init read-only memory' via the __ro_after_init attribute, and mark the ARM and x86 vDSO as such read-only memory. This kind of attribute can be used for data that requires a once per bootup initialization sequence, but is otherwise never modified after that point. This feature was based on the work by PaX Team and Brad Spengler. (by Kees Cook, the ARM vDSO bits by David Brown.) - make CONFIG_DEBUG_RODATA always enabled on x86 and remove the Kconfig option. This simplifies the kernel and also signals that read-only memory is the default model and a first-class citizen. (Kees Cook)" * 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ARM/vdso: Mark the vDSO code read-only after init x86/vdso: Mark the vDSO code read-only after init lkdtm: Verify that '__ro_after_init' works correctly arch: Introduce post-init read-only memory x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings asm-generic: Consolidate mark_rodata_ro()
2016-03-11arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permissionCatalin Marinas1-1/+2
The set_pte_at() function must update the hardware PTE_RDONLY bit depending on the state of the PTE_WRITE and PTE_DIRTY bits of the given entry value. However, it currently only performs this for pte_valid() entries, ignoring PTE_PROT_NONE. The side-effect is that PROT_NONE mappings would not have the PTE_RDONLY bit set. Without CONFIG_ARM64_HW_AFDBM, this is not an issue since such PROT_NONE pages are not accessible anyway. With commit 2f4b829c625e ("arm64: Add support for hardware updates of the access and dirty pte bits"), the ptep_set_wrprotect() function was re-written to cope with automatic hardware updates of the dirty state. As an optimisation, only PTE_RDONLY is checked to assess the "dirty" status. Since set_pte_at() does not set this bit for PROT_NONE mappings, such pages may be considered "dirty" as a result of ptep_set_wrprotect(). This patch updates the pte_valid() check to pte_present() in set_pte_at(). It also adds PTE_PROT_NONE to the swap entry bits comment. Fixes: 2f4b829c625e ("arm64: Add support for hardware updates of the access and dirty pte bits") Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> Tested-by: Ganapatrao Kulkarni <gkulkarni@cavium.com> Cc: <stable@vger.kernel.org>
2016-03-09arm64: account for sparsemem section alignment when choosing vmemmap offsetArd Biesheuvel1-2/+3
Commit dfd55ad85e4a ("arm64: vmemmap: use virtual projection of linear region") fixed an issue where the struct page array would overflow into the adjacent virtual memory region if system RAM was placed so high up in physical memory that its addresses were not representable in the build time configured virtual address size. However, the fix failed to take into account that the vmemmap region needs to be relatively aligned with respect to the sparsemem section size, so that a sequence of page structs corresponding with a sparsemem section in the linear region appears naturally aligned in the vmemmap region. So round up vmemmap to sparsemem section size. Since this essentially moves the projection of the linear region up in memory, also revert the reduction of the size of the vmemmap region. Cc: <stable@vger.kernel.org> Fixes: dfd55ad85e4a ("arm64: vmemmap: use virtual projection of linear region") Tested-by: Mark Langsdorf <mlangsdo@redhat.com> Tested-by: David Daney <david.daney@cavium.com> Tested-by: Robert Richter <rrichter@cavium.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-09arm64: KVM: vgic-v3: Reset LRs at boot timeMarc Zyngier1-0/+1
In order to let the GICv3 code be more lazy in the way it accesses the LRs, it is necessary to start with a clean slate. Let's reset the LRs on each CPU when the vgic is probed (which includes a round trip to EL2...). Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-03-07PCI: Move pci_dma_* helpers to common codeChristoph Hellwig1-1/+0
For a long time all architectures implement the pci_dma_* functions using the generic DMA API, and they all use the same header to do so. Move this header, pci-dma-compat.h, to include/linux and include it from the generic pci.h instead of having each arch duplicate this include. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-03-04arm64: Fix misspellings in comments.Adam Buchbinder3-4/+4
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-03-04arm64: make mrs_s prefixing implicit in read_cpuidMark Rutland2-5/+5
Commit 0f54b14e76f5302a ("arm64: cpufeature: Change read_cpuid() to use sysreg's mrs_s macro") changed read_cpuid to require a SYS_ prefix on register names, to allow manual assembly of registers unknown by the toolchain, using tables in sysreg.h. This interacts poorly with commit 42b55734030c1f72 ("efi/arm64: Check for h/w support before booting a >4 KB granular kernel"), which is curretly queued via the tip tree, and uses read_cpuid without a SYS_ prefix. Due to this, a build of next-20160304 fails if EFI and 64K pages are selected. To avoid this issue when trees are merged, move the required SYS_ prefixing into read_cpuid, and revert all of the updated callsites to pass plain register names. This effectively reverts the bulk of commit 0f54b14e76f5302a. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-03-02arm64: Rework valid_user_regsMark Rutland1-29/+4
We validate pstate using PSR_MODE32_BIT, which is part of the user-provided pstate (and cannot be trusted). Also, we conflate validation of AArch32 and AArch64 pstate values, making the code difficult to reason about. Instead, validate the pstate value based on the associated task. The task may or may not be current (e.g. when using ptrace), so this must be passed explicitly by callers. To avoid circular header dependencies via sched.h, is_compat_task is pulled out of asm/ptrace.h. To make the code possible to reason about, the AArch64 and AArch32 validation is split into separate functions. Software must respect the RES0 policy for SPSR bits, and thus the kernel mirrors the hardware policy (RAZ/WI) for bits as-yet unallocated. When these acquire an architected meaning writes may be permitted (potentially with additional validation). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Dave Martin <dave.martin@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-03-01arm64: KVM: Move kvm_call_hyp back to its original localtionMarc Zyngier1-2/+2
In order to reduce the risk of a bad merge, let's move the new kvm_call_hyp back to its original location in the file. This has zero impact from a code point of view. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-29arm64: KVM: Add a new vcpu device control group for PMUv3Shannon Zhao2-0/+11
To configure the virtual PMUv3 overflow interrupt number, we use the vcpu kvm_device ioctl, encapsulating the KVM_ARM_VCPU_PMU_V3_IRQ attribute within the KVM_ARM_VCPU_PMU_V3_CTRL group. After configuring the PMUv3, call the vcpu ioctl with attribute KVM_ARM_VCPU_PMU_V3_INIT to initialize the PMUv3. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Acked-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add a new feature bit for PMUv3Shannon Zhao2-1/+2
To support guest PMUv3, use one bit of the VCPU INIT feature array. Initialize the PMU when initialzing the vcpu with that bit and PMU overflow interrupt set. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Acked-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMUSERENR registerShannon Zhao3-0/+11
This register resets as unknown in 64bit mode while it resets as zero in 32bit mode. Here we choose to reset it as zero for consistency. PMUSERENR_EL0 holds some bits which decide whether PMU registers can be accessed from EL0. Add some check helpers to handle the access from EL0. When these bits are zero, only reading PMUSERENR will trap to EL2 and writing PMUSERENR or reading/writing other PMU registers will trap to EL1 other than EL2 when HCR.TGE==0. To current KVM configuration (HCR.TGE==0) there is no way to get these traps. Here we write 0xf to physical PMUSERENR register on VM entry, so that it will trap PMU access from EL0 to EL2. Within the register access handler we check the real value of guest PMUSERENR register to decide whether this access is allowed. If not allowed, return false to inject UND to guest. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add helper to handle PMCR register bitsShannon Zhao1-1/+3
According to ARMv8 spec, when writing 1 to PMCR.E, all counters are enabled by PMCNTENSET, while writing 0 to PMCR.E, all counters are disabled. When writing 1 to PMCR.P, reset all event counters, not including PMCCNTR, to zero. When writing 1 to PMCR.C, reset PMCCNTR to zero. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMSWINC registerShannon Zhao2-0/+3
Add access handler which emulates writing and reading PMSWINC register and add support for creating software increment event. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR registerShannon Zhao1-0/+1
Since the reset value of PMOVSSET and PMOVSCLR is UNKNOWN, use reset_unknown for its reset handler. Add a handler to emulate writing PMOVSSET or PMOVSCLR register. When writing non-zero value to PMOVSSET, the counter and its interrupt is enabled, kick this vcpu to sync PMU interrupt. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMINTENSET and PMINTENCLR registerShannon Zhao1-0/+1
Since the reset value of PMINTENSET and PMINTENCLR is UNKNOWN, use reset_unknown for its reset handler. Add a handler to emulate writing PMINTENSET or PMINTENCLR register. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for event type registerShannon Zhao1-0/+3
These kind of registers include PMEVTYPERn, PMCCFILTR and PMXEVTYPER which is mapped to PMEVTYPERn or PMCCFILTR. The access handler translates all aarch32 register offsets to aarch64 ones and uses vcpu_sys_reg() to access their values to avoid taking care of big endian. When writing to these registers, create a perf_event for the selected event type. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMCNTENSET and PMCNTENCLR registerShannon Zhao1-0/+1
Since the reset value of PMCNTENSET and PMCNTENCLR is UNKNOWN, use reset_unknown for its reset handler. Add a handler to emulate writing PMCNTENSET or PMCNTENCLR register. When writing to PMCNTENSET, call perf_event_enable to enable the perf event. When writing to PMCNTENCLR, call perf_event_disable to disable the perf event. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for event counter registerShannon Zhao1-0/+3
These kind of registers include PMEVCNTRn, PMCCNTR and PMXEVCNTR which is mapped to PMEVCNTRn. The access handler translates all aarch32 register offsets to aarch64 ones and uses vcpu_sys_reg() to access their values to avoid taking care of big endian. When reading these registers, return the sum of register value and the value perf event counts. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMSELR registerShannon Zhao1-0/+1
Since the reset value of PMSELR_EL0 is UNKNOWN, use reset_unknown for its reset handler. When reading PMSELR, return the PMSELR.SEL field to guest. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add access handler for PMCR registerShannon Zhao1-0/+3
Add reset handler which gets host value of PMCR_EL0 and make writable bits architecturally UNKNOWN except PMCR.E which is zero. Add an access handler for PMCR. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Define PMU data structure for each vcpuShannon Zhao1-0/+2
Here we plan to support virtual PMU for guest by full software emulation, so define some basic structs and functions preparing for futher steps. Define struct kvm_pmc for performance monitor counter and struct kvm_pmu for performance monitor unit for each vcpu. According to ARMv8 spec, the PMU contains at most 32(ARMV8_PMU_MAX_COUNTERS) counters. Since this only supports ARM64 (or PMUv3), add a separate config symbol for it. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Add temporary kvm_perf_event.hMarc Zyngier2-0/+56
In order to merge the KVM/ARM PMU patches without creating a conflict mess, let's have a temporary include file that won't conflict with anything. Subsequent patches will clean that up. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Move __cpu_init_stage2 after kvm_call_hypMarc Zyngier1-5/+7
In order to ease the merge with the rest of the arm64 tree, move the definition of __cpu_init_stage2() after what will be the new kvm_call_hyp. Hopefully the resolution of the merge conflict will be obvious. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.hMarc Zyngier1-0/+180
In order to be able to move code outside of kvm/hyp, we need to make the global hyp.h file accessible from a standard location. include/asm/kvm_hyp.h seems good enough. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: hw_breakpoint: Allow EL2 breakpoints if running in HYPMarc Zyngier1-5/+13
With VHE, we place kernel {watch,break}-points at EL2 to get things like kgdb and "perf -e mem:..." working. This requires a bit of repainting in the low-level encore/decode, but is otherwise pretty simple. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: VHE: Implement VHE activate/deactivate_trapsMarc Zyngier2-1/+5
Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: VHE: Make __fpsimd_enabled VHE awareMarc Zyngier1-0/+3
As non-VHE and VHE have different ways to express the trapping of FPSIMD registers to EL2, make __fpsimd_enabled a patchable predicate and provide a VHE implementation. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: VHE: Patch out kern_hyp_vaMarc Zyngier1-1/+11
The kern_hyp_va macro is pretty meaninless with VHE, as there is only one mapping - the kernel one. In order to keep the code readable and efficient, use runtime patching to replace the 'and' instruction used to compute the VA with a 'nop'. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: Add ARM64_HAS_VIRT_HOST_EXTN featureMarc Zyngier1-1/+5
Add a new ARM64_HAS_VIRT_HOST_EXTN features to indicate that the CPU has the ARMv8.1 VHE capability. This will be used to trigger kernel patching in KVM. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm/arm64: Add new is_kernel_in_hyp_mode predicateMarc Zyngier1-0/+10
With ARMv8.1 VHE extension, it will be possible to run the kernel at EL2 (aka HYP mode). In order for the kernel to easily find out where it is running, add a new predicate that returns whether or not the kernel is in HYP mode. For completeness, the 32bit code also get such a predicate (always returning false) so that code common to both architecture (timers, KVM) can use it transparently. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: KVM: Switch to C-based stage2 initMarc Zyngier2-0/+4
There is no real need to leave the stage2 initialization as part of the early HYP bootstrap, and we can easily postpone it to the point where we can safely run C code. This will help VHE, which doesn't need any of this bootstrap. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm/arm64: KVM: Handle out-of-RAM cache maintenance as a NOPMarc Zyngier1-0/+5
So far, our handling of cache maintenance by VA has been pretty simple: Either the access is in the guest RAM and generates a S2 fault, which results in the page being mapped RW, or we go down the io_mem_abort() path, and nuke the guest. The first one is fine, but the second one is extremely weird. Treating the CM as an I/O is wrong, and nothing in the ARM ARM indicates that we should generate a fault for something that cannot end-up in the cache anyway (even if the guest maps it, it will keep on faulting at stage-2 for emulation). So let's just skip this instruction, and let the guest get away with it. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29ARM: KVM: Remove __kvm_hyp_code_start/__kvm_hyp_code_endMarc Zyngier1-3/+0
Now that we've unified the way we refer to the HYP text between arm and arm64, drop __kvm_hyp_code_start/end, and just use the __hyp_text_start/end symbols. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm/arm64: KVM: Add hook for C-based stage2 initMarc Zyngier1-0/+4
As we're about to move the stage2 init to C code, introduce some C hooks that will later be populated with arch-specific implementations. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29arm64: mm: treat memstart_addr as a signed quantityArd Biesheuvel1-1/+1
Commit c031a4213c11 ("arm64: kaslr: randomize the linear region") implements randomization of the linear region, by subtracting a random multiple of PUD_SIZE from memstart_addr. This causes the virtual mapping of system RAM to move upwards in the linear region, and at the same time causes memstart_addr to assume a value which may be negative if the offset of system RAM in the physical space is smaller than its offset relative to PAGE_OFFSET in the virtual space. Since memstart_addr is effectively an offset now, redefine its type as s64 so that expressions involving shifting or division preserve its sign. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>