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2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 67 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141333.953658117@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19KVM: arm/arm64: vgic-its: Take the srcu lock when writing to guest memoryMarc Zyngier
When halting a guest, QEMU flushes the virtual ITS caches, which amounts to writing to the various tables that the guest has allocated. When doing this, we fail to take the srcu lock, and the kernel shouts loudly if running a lockdep kernel: [ 69.680416] ============================= [ 69.680819] WARNING: suspicious RCU usage [ 69.681526] 5.1.0-rc1-00008-g600025238f51-dirty #18 Not tainted [ 69.682096] ----------------------------- [ 69.682501] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage! [ 69.683225] [ 69.683225] other info that might help us debug this: [ 69.683225] [ 69.683975] [ 69.683975] rcu_scheduler_active = 2, debug_locks = 1 [ 69.684598] 6 locks held by qemu-system-aar/4097: [ 69.685059] #0: 0000000034196013 (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0 [ 69.686087] #1: 00000000f2ed935e (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0 [ 69.686919] #2: 000000005e71ea54 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.687698] #3: 00000000c17e548d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.688475] #4: 00000000ba386017 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.689978] #5: 00000000c2c3c335 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0 [ 69.690729] [ 69.690729] stack backtrace: [ 69.691151] CPU: 2 PID: 4097 Comm: qemu-system-aar Not tainted 5.1.0-rc1-00008-g600025238f51-dirty #18 [ 69.691984] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019 [ 69.692831] Call trace: [ 69.694072] lockdep_rcu_suspicious+0xcc/0x110 [ 69.694490] gfn_to_memslot+0x174/0x190 [ 69.694853] kvm_write_guest+0x50/0xb0 [ 69.695209] vgic_its_save_tables_v0+0x248/0x330 [ 69.695639] vgic_its_set_attr+0x298/0x3a0 [ 69.696024] kvm_device_ioctl_attr+0x9c/0xd8 [ 69.696424] kvm_device_ioctl+0x8c/0xf8 [ 69.696788] do_vfs_ioctl+0xc8/0x960 [ 69.697128] ksys_ioctl+0x8c/0xa0 [ 69.697445] __arm64_sys_ioctl+0x28/0x38 [ 69.697817] el0_svc_common+0xd8/0x138 [ 69.698173] el0_svc_handler+0x38/0x78 [ 69.698528] el0_svc+0x8/0xc The fix is to obviously take the srcu lock, just like we do on the read side of things since bf308242ab98. One wonders why this wasn't fixed at the same time, but hey... Fixes: bf308242ab98 ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-19KVM: arm/arm64: Factor out VMID into struct kvm_vmidChristoffer Dall
In preparation for nested virtualization where we are going to have more than a single VMID per VM, let's factor out the VMID data into a separate VMID data structure and change the VMID allocator to operate on this new structure instead of using a struct kvm. This also means that udate_vttbr now becomes update_vmid, and that the vttbr itself is generated on the fly based on the stage 2 page table base address and the vmid. We cache the physical address of the pgd when allocating the pgd to avoid doing the calculation on every entry to the guest and to avoid calling into potentially non-hyp-mapped code from hyp/EL2. If we wanted to merge the VMID allocator with the arm64 ASID allocator at some point in the future, it should actually become easier to do that after this patch. Note that to avoid mapping the kvm_vmid_bits variable into hyp, we simply forego the masking of the vmid value in kvm_get_vttbr and rely on update_vmid to always assign a valid vmid value (within the supported range). Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> [maz: minor cleanups] Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-18KVM: arm64: Add support for creating PUD hugepages at stage 2Punit Agrawal
KVM only supports PMD hugepages at stage 2. Now that the various page handling routines are updated, extend the stage 2 fault handling to map in PUD hugepages. Addition of PUD hugepage support enables additional page sizes (e.g., 1G with 4K granule) which can be useful on cores that support mapping larger block sizes in the TLB entries. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [ Replace BUG() => WARN_ON(1) for arm32 PUD helpers ] Signed-off-by: Suzuki Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-18KVM: arm64: Update age handlers to support PUD hugepagesPunit Agrawal
In preparation for creating larger hugepages at Stage 2, add support to the age handling notifiers for PUD hugepages when encountered. Provide trivial helpers for arm32 to allow sharing code. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [ Replaced BUG() => WARN_ON(1) for arm32 PUD helpers ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-18KVM: arm64: Support handling access faults for PUD hugepagesPunit Agrawal
In preparation for creating larger hugepages at Stage 2, extend the access fault handling at Stage 2 to support PUD hugepages when encountered. Provide trivial helpers for arm32 to allow sharing of code. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [ Replaced BUG() => WARN_ON(1) in PUD helpers ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-18KVM: arm64: Support PUD hugepage in stage2_is_exec()Punit Agrawal
In preparation for creating PUD hugepages at stage 2, add support for detecting execute permissions on PUD page table entries. Faults due to lack of execute permissions on page table entries is used to perform i-cache invalidation on first execute. Provide trivial implementations of arm32 helpers to allow sharing of code. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [ Replaced BUG() => WARN_ON(1) in arm32 PUD helpers ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-18KVM: arm64: Support dirty page tracking for PUD hugepagesPunit Agrawal
In preparation for creating PUD hugepages at stage 2, add support for write protecting PUD hugepages when they are encountered. Write protecting guest tables is used to track dirty pages when migrating VMs. Also, provide trivial implementations of required kvm_s2pud_* helpers to allow sharing of code with arm32. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> [ Replaced BUG() => WARN_ON() in arm32 pud helpers ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-18KVM: arm/arm64: Introduce helpers to manipulate page table entriesPunit Agrawal
Introduce helpers to abstract architectural handling of the conversion of pfn to page table entries and marking a PMD page table entry as a block entry. The helpers are introduced in preparation for supporting PUD hugepages at stage 2 - which are supported on arm64 but do not exist on arm. Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-10-25Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Radim Krčmář: "ARM: - Improved guest IPA space support (32 to 52 bits) - RAS event delivery for 32bit - PMU fixes - Guest entry hardening - Various cleanups - Port of dirty_log_test selftest PPC: - Nested HV KVM support for radix guests on POWER9. The performance is much better than with PR KVM. Migration and arbitrary level of nesting is supported. - Disable nested HV-KVM on early POWER9 chips that need a particular hardware bug workaround - One VM per core mode to prevent potential data leaks - PCI pass-through optimization - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base s390: - Initial version of AP crypto virtualization via vfio-mdev - Improvement for vfio-ap - Set the host program identifier - Optimize page table locking x86: - Enable nested virtualization by default - Implement Hyper-V IPI hypercalls - Improve #PF and #DB handling - Allow guests to use Enlightened VMCS - Add migration selftests for VMCS and Enlightened VMCS - Allow coalesced PIO accesses - Add an option to perform nested VMCS host state consistency check through hardware - Automatic tuning of lapic_timer_advance_ns - Many fixes, minor improvements, and cleanups" * tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned Revert "kvm: x86: optimize dr6 restore" KVM: PPC: Optimize clearing TCEs for sparse tables x86/kvm/nVMX: tweak shadow fields selftests/kvm: add missing executables to .gitignore KVM: arm64: Safety check PSTATE when entering guest and handle IL KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips arm/arm64: KVM: Enable 32 bits kvm vcpu events support arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension() KVM: arm64: Fix caching of host MDCR_EL2 value KVM: VMX: enable nested virtualization by default KVM/x86: Use 32bit xor to clear registers in svm.c kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD kvm: vmx: Defer setting of DR6 until #DB delivery kvm: x86: Defer setting of CR2 until #PF delivery kvm: x86: Add payload operands to kvm_multiple_exception kvm: x86: Add exception payload fields to kvm_vcpu_events kvm: x86: Add has_payload and payload to kvm_queued_exception KVM: Documentation: Fix omission in struct kvm_vcpu_events KVM: selftests: add Enlightened VMCS test ...
2018-10-03kvm: arm64: Set a limit on the IPA sizeSuzuki K Poulose
So far we have restricted the IPA size of the VM to the default value (40bits). Now that we can manage the IPA size per VM and support dynamic stage2 page tables, we can allow VMs to have larger IPA. This patch introduces a the maximum IPA size supported on the host. This is decided by the following factors : 1) Maximum PARange supported by the CPUs - This can be inferred from the system wide safe value. 2) Maximum PA size supported by the host kernel (48 vs 52) 3) Number of levels in the host page table (as we base our stage2 tables on the host table helpers). Since the stage2 page table code is dependent on the stage1 page table, we always ensure that : Number of Levels at Stage1 >= Number of Levels at Stage2 So we limit the IPA to make sure that the above condition is satisfied. This will affect the following combinations of VA_BITS and IPA for different page sizes. Host configuration | Unsupported IPA ranges 39bit VA, 4K | [44, 48] 36bit VA, 16K | [41, 48] 42bit VA, 64K | [47, 52] Supporting the above combinations need independent stage2 page table manipulation code, which would need substantial changes. We could purse the solution independently and switch the page table code once we have it ready. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Christoffer Dall <cdall@kernel.org> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-10-01kvm: arm/arm64: Prepare for VM specific stage2 translationsSuzuki K Poulose
Right now the stage2 page table for a VM is hard coded, assuming an IPA of 40bits. As we are about to add support for per VM IPA, prepare the stage2 page table helpers to accept the kvm instance to make the right decision for the VM. No functional changes. Adds stage2_pgd_size(kvm) to replace S2_PGD_SIZE. Also, moves some of the definitions in arm32 to align with the arm64. Also drop the _AC() specifier constants wherever possible. Cc: Christoffer Dall <cdall@kernel.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-09-18arm64: KVM: Enable Common Not Private translationsVladimir Murzin
We rely on cpufeature framework to detect and enable CNP so for KVM we need to patch hyp to set CNP bit just before TTBR0_EL2 gets written. For the guest we encode CNP bit while building vttbr, so we don't need to bother with that in a world switch. Reviewed-by: James Morse <james.morse@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-07-09KVM: arm/arm64: Stop using the kernel's {pmd,pud,pgd}_populate helpersMarc Zyngier
The {pmd,pud,pgd}_populate accessors usage have always been a bit weird in KVM. We don't have a struct mm to pass (and neither does the kernel most of the time, but still...), and the 32bit code has all kind of cache maintenance that doesn't make sense on ARMv7+ when MP extensions are mandatory (which is the case when the VEs are present). Let's bite the bullet and provide our own implementations. The only bit of architectural code left has to do with building the table entry itself (arm64 having up to 52bit PA, arm lacking PUD level). Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-07-09KVM: arm/arm64: Consolidate page-table accessorsMarc Zyngier
The arm and arm64 KVM page tables accessors are pointlessly different between the two architectures, and likely both wrong one way or another: arm64 lacks a dsb(), and arm doesn't use WRITE_ONCE. Let's unify them. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-06-08Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Apart from the core arm64 and perf changes, the Spectre v4 mitigation touches the arm KVM code and the ACPI PPTT support touches drivers/ (acpi and cacheinfo). I should have the maintainers' acks in place. Summary: - Spectre v4 mitigation (Speculative Store Bypass Disable) support for arm64 using SMC firmware call to set a hardware chicken bit - ACPI PPTT (Processor Properties Topology Table) parsing support and enable the feature for arm64 - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The primary motivation is Scalable Vector Extensions which requires more space on the signal frame than the currently defined MINSIGSTKSZ - ARM perf patches: allow building arm-cci as module, demote dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous cleanups - cmpwait() WFE optimisation to avoid some spurious wakeups - L1_CACHE_BYTES reverted back to 64 (for performance reasons that have to do with some network allocations) while keeping ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual hardware Cache Writeback Granule - Turn LSE atomics on by default in Kconfig - Kernel fault reporting tidying - Some #include and miscellaneous cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits) arm64: Fix syscall restarting around signal suppressed by tracer arm64: topology: Avoid checking numa mask for scheduler MC selection ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled arm64: cpu_errata: include required headers arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file arm64: signal: Report signal frame size to userspace via auxv arm64/sve: Thin out initialisation sanity-checks for sve_max_vl arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests arm64: KVM: Add ARCH_WORKAROUND_2 support for guests arm64: KVM: Add HYP per-cpu accessors arm64: ssbd: Add prctl interface for per-thread mitigation arm64: ssbd: Introduce thread flag to control userspace mitigation arm64: ssbd: Restore mitigation status on CPU resume arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation arm64: ssbd: Add global mitigation state accessor arm64: Add 'ssbd' command-line option arm64: Add ARCH_WORKAROUND_2 probing arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2 arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1 ...
2018-06-06Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM updates from Russell King: - Initial round of Spectre variant 1 and variant 2 fixes for 32-bit ARM - Clang support improvements - nommu updates for v8 MPU - enable ARM_MODULE_PLTS by default to avoid problems loading modules with larger kernels - vmlinux.lds and dma-mapping cleanups * 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (31 commits) ARM: spectre-v1: fix syscall entry ARM: spectre-v1: add array_index_mask_nospec() implementation ARM: spectre-v1: add speculation barrier (csdb) macros ARM: KVM: report support for SMCCC_ARCH_WORKAROUND_1 ARM: KVM: Add SMCCC_ARCH_WORKAROUND_1 fast handling ARM: spectre-v2: KVM: invalidate icache on guest exit for Brahma B15 ARM: KVM: invalidate icache on guest exit for Cortex-A15 ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17 ARM: spectre-v2: warn about incorrect context switching functions ARM: spectre-v2: add firmware based hardening ARM: spectre-v2: harden user aborts in kernel space ARM: spectre-v2: add Cortex A8 and A15 validation of the IBE bit ARM: spectre-v2: harden branch predictor on context switches ARM: spectre: add Kconfig symbol for CPUs vulnerable to Spectre ARM: bugs: add support for per-processor bug checking ARM: bugs: hook processor bug checking into SMP and suspend paths ARM: bugs: prepare processor bug infrastructure ARM: add more CPU part numbers for Cortex and Brahma B15 CPUs ARM: 8774/1: remove no-op macro VMLINUX_SYMBOL() ARM: 8773/1: amba: Export amba_bustype ...
2018-06-05Merge branches 'fixes', 'misc' and 'spectre' into for-linusRussell King
2018-05-31arm64: KVM: Add ARCH_WORKAROUND_2 support for guestsMarc Zyngier
In order to offer ARCH_WORKAROUND_2 support to guests, we need a bit of infrastructure. Let's add a flag indicating whether or not the guest uses SSBD mitigation. Depending on the state of this flag, allow KVM to disable ARCH_WORKAROUND_2 before entering the guest, and enable it when exiting it. Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31ARM: spectre-v2: KVM: invalidate icache on guest exit for Brahma B15Russell King
Include Brahma B15 in the Spectre v2 KVM workarounds. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2018-05-31ARM: KVM: invalidate icache on guest exit for Cortex-A15Marc Zyngier
In order to avoid aliasing attacks against the branch predictor on Cortex-A15, let's invalidate the BTB on guest exit, which can only be done by invalidating the icache (with ACTLR[0] being set). We use the same hack as for A12/A17 to perform the vector decoding. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
2018-05-31ARM: KVM: invalidate BTB on guest exit for Cortex-A12/A17Marc Zyngier
In order to avoid aliasing attacks against the branch predictor, let's invalidate the BTB on guest exit. This is made complicated by the fact that we cannot take a branch before invalidating the BTB. We only apply this to A12 and A17, which are the only two ARM cores on which this useful. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Boot-tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Tony Lindgren <tony@atomide.com>
2018-05-15KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lockAndre Przywara
kvm_read_guest() will eventually look up in kvm_memslots(), which requires either to hold the kvm->slots_lock or to be inside a kvm->srcu critical section. In contrast to x86 and s390 we don't take the SRCU lock on every guest exit, so we have to do it individually for each kvm_read_guest() call. Provide a wrapper which does that and use that everywhere. Note that ending the SRCU critical section before returning from the kvm_read_guest() wrapper is safe, because the data has been *copied*, so we don't need to rely on valid references to the memslot anymore. Cc: Stable <stable@vger.kernel.org> # 4.8+ Reported-by: Jan Glauber <jan.glauber@caviumnetworks.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-19arm/arm64: KVM: Introduce EL2-specific executable mappingsMarc Zyngier
Until now, all EL2 executable mappings were derived from their EL1 VA. Since we want to decouple the vectors mapping from the rest of the hypervisor, we need to be able to map some text somewhere else. The "idmap" region (for lack of a better name) is ideally suited for this, as we have a huge range that hardly has anything in it. Let's extend the IO allocator to also deal with executable mappings, thus providing the required feature. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move HYP IO VAs to the "idmap" rangeMarc Zyngier
We so far mapped our HYP IO (which is essentially the GICv2 control registers) using the same method as for memory. It recently appeared that is a bit unsafe: We compute the HYP VA using the kern_hyp_va helper, but that helper is only designed to deal with kernel VAs coming from the linear map, and not from the vmalloc region... This could in turn cause some bad aliasing between the two, amplified by the upcoming VA randomisation. A solution is to come up with our very own basic VA allocator for MMIO. Since half of the HYP address space only contains a single page (the idmap), we have plenty to borrow from. Let's use the idmap as a base, and allocate downwards from it. GICv2 now lives on the other side of the great VA barrier. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Keep GICv2 HYP VAs in kvm_vgic_global_stateMarc Zyngier
As we're about to change the way we map devices at HYP, we need to move away from kern_hyp_va on an IO address. One way of achieving this is to store the VAs in kvm_vgic_global_state, and use that directly from the HYP code. This requires a small change to create_hyp_io_mappings so that it can also return a HYP VA. We take this opportunity to nuke the vctrl_base field in the emulated distributor, as it is not used anymore. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Move ioremap calls to create_hyp_io_mappingsMarc Zyngier
Both HYP io mappings call ioremap, followed by create_hyp_io_mappings. Let's move the ioremap call into create_hyp_io_mappings itself, which simplifies the code a bit and allows for further refactoring. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Do not use kern_hyp_va() with kvm_vgic_global_stateMarc Zyngier
kvm_vgic_global_state is part of the read-only section, and is usually accessed using a PC-relative address generation (adrp + add). It is thus useless to use kern_hyp_va() on it, and actively problematic if kern_hyp_va() becomes non-idempotent. On the other hand, there is no way that the compiler is going to guarantee that such access is always PC relative. So let's bite the bullet and provide our own accessor. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-02-10Merge tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Radim Krčmář: "ARM: - icache invalidation optimizations, improving VM startup time - support for forwarded level-triggered interrupts, improving performance for timers and passthrough platform devices - a small fix for power-management notifiers, and some cosmetic changes PPC: - add MMIO emulation for vector loads and stores - allow HPT guests to run on a radix host on POWER9 v2.2 CPUs without requiring the complex thread synchronization of older CPU versions - improve the handling of escalation interrupts with the XIVE interrupt controller - support decrement register migration - various cleanups and bugfixes. s390: - Cornelia Huck passed maintainership to Janosch Frank - exitless interrupts for emulated devices - cleanup of cpuflag handling - kvm_stat counter improvements - VSIE improvements - mm cleanup x86: - hypervisor part of SEV - UMIP, RDPID, and MSR_SMI_COUNT emulation - paravirtualized TLB shootdown using the new KVM_VCPU_PREEMPTED bit - allow guests to see TOPOEXT, GFNI, VAES, VPCLMULQDQ, and more AVX512 features - show vcpu id in its anonymous inode name - many fixes and cleanups - per-VCPU MSR bitmaps (already merged through x86/pti branch) - stable KVM clock when nesting on Hyper-V (merged through x86/hyperv)" * tag 'kvm-4.16-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (197 commits) KVM: PPC: Book3S: Add MMIO emulation for VMX instructions KVM: PPC: Book3S HV: Branch inside feature section KVM: PPC: Book3S HV: Make HPT resizing work on POWER9 KVM: PPC: Book3S HV: Fix handling of secondary HPTEG in HPT resizing code KVM: PPC: Book3S PR: Fix broken select due to misspelling KVM: x86: don't forget vcpu_put() in kvm_arch_vcpu_ioctl_set_sregs() KVM: PPC: Book3S PR: Fix svcpu copying with preemption enabled KVM: PPC: Book3S HV: Drop locks before reading guest memory kvm: x86: remove efer_reload entry in kvm_vcpu_stat KVM: x86: AMD Processor Topology Information x86/kvm/vmx: do not use vm-exit instruction length for fast MMIO when running nested kvm: embed vcpu id to dentry of vcpu anon inode kvm: Map PFN-type memory regions as writable (if possible) x86/kvm: Make it compile on 32bit and with HYPYERVISOR_GUEST=n KVM: arm/arm64: Fixup userspace irqchip static key optimization KVM: arm/arm64: Fix userspace_irqchip_in_use counting KVM: arm/arm64: Fix incorrect timer_is_pending logic MAINTAINERS: update KVM/s390 maintainers MAINTAINERS: add Halil as additional vfio-ccw maintainer MAINTAINERS: add David as a reviewer for KVM/s390 ...
2018-01-08arm64: KVM: Use per-CPU vector when BP hardening is enabledMarc Zyngier
Now that we have per-CPU vectors, let's plug then in the KVM/arm64 code. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-08KVM: arm/arm64: Drop vcpu parameter from guest cache maintenance operartionsMarc Zyngier
The vcpu parameter isn't used for anything, and gets in the way of further cleanups. Let's get rid of it. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08KVM: arm/arm64: Preserve Exec permission across R/W permission faultsMarc Zyngier
So far, we loose the Exec property whenever we take permission faults, as we always reconstruct the PTE/PMD from scratch. This can be counter productive as we can end-up with the following fault sequence: X -> RO -> ROX -> RW -> RWX Instead, we can lookup the existing PTE/PMD and clear the XN bit in the new entry if it was already cleared in the old one, leadig to a much nicer fault sequence: X -> ROX -> RWX Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08KVM: arm/arm64: Limit icache invalidation to prefetch abortsMarc Zyngier
We've so far eagerly invalidated the icache, no matter how the page was faulted in (data or prefetch abort). But we can easily track execution by setting the XN bits in the S2 page tables, get the prefetch abort at HYP and perform the icache invalidation at that time only. As for most VMs, the instruction working set is pretty small compared to the data set, this is likely to save some traffic (specially as the invalidation is broadcast). Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08arm: KVM: Add optimized PIPT icache flushingMarc Zyngier
Calling __cpuc_coherent_user_range to invalidate the icache on a PIPT icache machine has some pointless overhead, as it starts by cleaning the dcache to the PoU, while we're guaranteed to have already cleaned it to the PoC. As KVM is the only user of such a feature, let's implement some ad-hoc cache flushing in kvm_mmu.h. Should it become useful to other subsystems, it can be moved to a more global location. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-08KVM: arm/arm64: Split dcache/icache flushingMarc Zyngier
As we're about to introduce opportunistic invalidation of the icache, let's split dcache and icache flushing. Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-22arm64: allow ID map to be extended to 52 bitsKristina Martsenko
Currently, when using VA_BITS < 48, if the ID map text happens to be placed in physical memory above VA_BITS, we increase the VA size (up to 48) and create a new table level, in order to map in the ID map text. This is okay because the system always supports 48 bits of VA. This patch extends the code such that if the system supports 52 bits of VA, and the ID map text is placed that high up, then we increase the VA size accordingly, up to 52. One difference from the current implementation is that so far the condition of VA_BITS < 48 has meant that the top level table is always "full", with the maximum number of entries, and an extra table level is always needed. Now, when VA_BITS = 48 (and using 64k pages), the top level table is not full, and we simply need to increase the number of entries in it, instead of creating a new table level. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()] [catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22arm64: handle 52-bit addresses in TTBRKristina Martsenko
The top 4 bits of a 52-bit physical address are positioned at bits 2..5 in the TTBR registers. Introduce a couple of macros to move the bits there, and change all TTBR writers to use them. Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with 52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a system without 52-bit PA can only use up to 48-bit PAs. A later patch in this series will add a kconfig dependency to ensure PAN is configured. In addition, when using 52-bit PA there is a special alignment requirement on the top-level table. We don't currently have any VA_BITS configuration that would violate the requirement, but one could be added in the future, so add a compile-time BUG_ON to check for it. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-09arm/arm64: KVM: Remove kvm_get_idmap_startMarc Zyngier
With __cpu_reset_hyp_mode having become fairly dumb, there is no need for kvm_get_idmap_start anymore. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-01-30arm/arm64: KVM: Stop propagating cacheability status of a faulted pageMarc Zyngier
Now that we unconditionally flush newly mapped pages to the PoC, there is no need to care about the "uncached" status of individual pages - they must all be visible all the way down. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-30arm/arm64: KVM: Enforce unconditional flush to PoC when mapping to stage-2Marc Zyngier
When we fault in a page, we flush it to the PoC (Point of Coherency) if the faulting vcpu has its own caches off, so that it can observe the page we just brought it. But if the vcpu has its caches on, we skip that step. Bad things happen when *another* vcpu tries to access that page with its own caches disabled. At that point, there is no garantee that the data has made it to the PoC, and we access stale data. The obvious fix is to always flush to PoC when a page is faulted in, no matter what the state of the vcpu is. Cc: stable@vger.kernel.org Fixes: 2d58b733c876 ("arm64: KVM: force cache clean on page fault when caches are off") Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-09-08arm/kvm: excise redundant cache maintenanceMark Rutland
When modifying Stage-2 page tables, we perform cache maintenance to account for non-coherent page table walks. However, this is unnecessary, as page table walks are guaranteed to be coherent in the presence of the virtualization extensions. Per ARM DDI 0406C.c, section B1.7 ("The Virtualization Extensions"), the virtualization extensions mandate the multiprocessing extensions. Per ARM DDI 0406C.c, section B3.10.1 ("General TLB maintenance requirements"), as described in the sub-section titled "TLB maintenance operations and the memory order model", this maintenance is not required in the presence of the multiprocessing extensions. Hence, we need not perform this cache maintenance when modifying Stage-2 entries. This patch removes the logic for performing the redundant maintenance. To ensure visibility and ordering of updates, a dsb(ishst) that was otherwise implicit in the maintenance is folded into kvm_set_pmd() and kvm_set_pte(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03arm/arm64: Get rid of KERN_TO_HYPMarc Zyngier
We have both KERN_TO_HYP and kern_hyp_va, which do the exact same thing. Let's standardize on the latter. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03arm/arm64: KVM: Prune unused #definesMarc Zyngier
We can now remove a number of dead #defines, thanks to the trampoline code being gone. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03arm/arm64: KVM: Kill free_boot_hyp_pgdMarc Zyngier
There is no way to free the boot PGD, because it doesn't exist anymore as a standalone entity. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-07-03arm/arm64: KVM: Drop boot_pgdMarc Zyngier
Since we now only have one set of page tables, the concept of boot_pgd is useless and can be removed. We still keep it as an element of the "extended idmap" thing. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-29arm/arm64: KVM: Add a protection parameter to create_hyp_mappingsMarc Zyngier
Currently, create_hyp_mappings applies a "one size fits all" page protection (PAGE_HYP). As we're heading towards separate protections for different sections, let's make this protection a parameter, and let the callers pass their prefered protection (PAGE_HYP for everyone for the time being). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-19Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "Small release overall. x86: - miscellaneous fixes - AVIC support (local APIC virtualization, AMD version) s390: - polling for interrupts after a VCPU goes to halted state is now enabled for s390 - use hardware provided information about facility bits that do not need any hypervisor activity, and other fixes for cpu models and facilities - improve perf output - floating interrupt controller improvements. MIPS: - miscellaneous fixes PPC: - bugfixes only ARM: - 16K page size support - generic firmware probing layer for timer and GIC Christoffer Dall (KVM-ARM maintainer) says: "There are a few changes in this pull request touching things outside KVM, but they should all carry the necessary acks and it made the merge process much easier to do it this way." though actually the irqchip maintainers' acks didn't make it into the patches. Marc Zyngier, who is both irqchip and KVM-ARM maintainer, later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more formally and for documentation purposes')" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits) KVM: MTRR: remove MSR 0x2f8 KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same svm: Manage vcpu load/unload when enable AVIC svm: Do not intercept CR8 when enable AVIC svm: Do not expose x2APIC when enable AVIC KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore svm: Add VMEXIT handlers for AVIC svm: Add interrupt injection via AVIC KVM: x86: Detect and Initialize AVIC support svm: Introduce new AVIC VMCB registers KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg KVM: x86: Misc LAPIC changes to expose helper functions KVM: shrink halt polling even more for invalid wakeups KVM: s390: set halt polling to 80 microseconds KVM: halt_polling: provide a way to qualify wakeups during poll KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts kvm: Conditionally register IRQ bypass consumer ...
2016-05-09kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tablesCatalin Marinas
The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 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: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-28arm64: kvm: allows kvm cpu hotplugAKASHI Takahiro
The current kvm implementation on arm64 does cpu-specific initialization at system boot, and has no way to gracefully shutdown a core in terms of kvm. This prevents kexec from rebooting the system at EL2. This patch adds a cpu tear-down function and also puts an existing cpu-init code into a separate function, kvm_arch_hardware_disable() and kvm_arch_hardware_enable() respectively. We don't need the arm64 specific cpu hotplug hook any more. Since this patch modifies common code between arm and arm64, one stub definition, __cpu_reset_hyp_mode(), is added on arm side to avoid compilation errors. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> [Rebase, added separate VHE init/exit path, changed resets use of kvm_call_hyp() to the __version, en/disabled hardware in init_subsystems(), added icache maintenance to __kvm_hyp_reset() and removed lr restore, removed guest-enter after teardown handling] Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-21kvm-arm: Cleanup stage2 pgd handlingSuzuki K Poulose
Now that we don't have any fake page table levels for arm64, cleanup the common code to get rid of the dead code. Cc: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>