wireguard-linux/arch/arm64/include/asm/kvm_hyp.h, branch jd/orphan-parallel

KVM: arm64: nVHE: Handle hyp panics

2020-09-15T17:39:03Z

Restore the host context when panicking from hyp to give the best chance of the panic being clean. The host requires that registers be preserved such as x18 for the shadow callstack. If the panic is caused by an exception from EL1, the host context is still valid so the panic can return straight back to the host. If the panic comes from EL2 then it's most likely that the hyp context is active and the host context needs to be restored. There are windows before and after the host context is saved and restored that restoration is attempted incorrectly and the panic won't be clean. Signed-off-by: Andrew Scull Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200915104643.2543892-14-ascull@google.com

KVM: arm64: Introduce hyp context

2020-09-15T17:39:02Z

During __guest_enter, save and restore from a new hyp context rather than the host context. This is preparation for separation of the hyp and host context in nVHE. Signed-off-by: Andrew Scull Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200915104643.2543892-9-ascull@google.com

KVM: arm64: Save chosen hyp vector to a percpu variable

2020-09-15T17:39:02Z

Introduce a percpu variable to hold the address of the selected hyp vector that will be used with guests. This avoids the selection process each time a guest is being entered and can be used by nVHE when a separate vector is introduced for the host. Signed-off-by: Andrew Scull Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200915104643.2543892-6-ascull@google.com

KVM: arm64: Remove hyp_panic arguments

2020-09-15T17:39:01Z

hyp_panic is able to find all the context it needs from within itself so remove the argument. The __hyp_panic wrapper becomes redundant so is also removed. Signed-off-by: Andrew Scull Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200915104643.2543892-3-ascull@google.com

KVM: arm64: Remove __hyp_text macro, use build rules instead

2020-07-05T17:38:45Z

With nVHE code now fully separated from the rest of the kernel, the effects of the __hyp_text macro (which had to be applied on all nVHE code) can be achieved with build rules instead. The macro used to: (a) move code to .hyp.text ELF section, now done by renaming .text using `objcopy`, and (b) `notrace` and `__noscs` would negate effects of CC_FLAGS_FTRACE and CC_FLAGS_SCS, respectivelly, now those flags are erased from KBUILD_CFLAGS (same way as in EFI stub). Note that by removing __hyp_text from code shared with VHE, all VHE code is now compiled into .text and without `notrace` and `__noscs`. Use of '.pushsection .hyp.text' removed from assembly files as this is now also covered by the build rules. For MAINTAINERS: if needed to re-run, uses of macro were removed with the following command. Formatting was fixed up manually. find arch/arm64/kvm/hyp -type f -name '*.c' -o -name '*.h' \ -exec sed -i 's/ __hyp_text//g' {} + Signed-off-by: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200625131420.71444-15-dbrazdil@google.com

KVM: arm64: Duplicate hyp/timer-sr.c for VHE/nVHE

2020-07-05T17:38:38Z

timer-sr.c contains a HVC handler for setting CNTVOFF_EL2 and two helper functions for controlling access to physical counter. The former is used by both VHE/nVHE and is duplicated, the latter are used only by nVHE and moved to nvhe/timer-sr.c. Signed-off-by: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200625131420.71444-13-dbrazdil@google.com

KVM: arm64: Split hyp/sysreg-sr.c to VHE/nVHE

2020-07-05T17:38:29Z

sysreg-sr.c contains KVM's code for saving/restoring system registers, with some code shared between VHE/nVHE. These common routines are moved to a header file, VHE-specific code is moved to vhe/sysreg-sr.c and nVHE-specific code to nvhe/sysreg-sr.c. Signed-off-by: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200625131420.71444-12-dbrazdil@google.com

KVM: arm64: Split hyp/switch.c to VHE/nVHE

2020-07-05T17:38:21Z

switch.c implements context-switching for KVM, with large parts shared between VHE/nVHE. These common routines are moved to a header file, VHE-specific code is moved to vhe/switch.c and nVHE-specific code is moved to nvhe/switch.c. Previously __kvm_vcpu_run needed a different symbol name for VHE/nVHE. This is cleaned up and the caller in arm.c simplified. Signed-off-by: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200625131420.71444-10-dbrazdil@google.com

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2020-06-03T22:13:47Z

Pull kvm updates from Paolo Bonzini: "ARM: - Move the arch-specific code into arch/arm64/kvm - Start the post-32bit cleanup - Cherry-pick a few non-invasive pre-NV patches x86: - Rework of TLB flushing - Rework of event injection, especially with respect to nested virtualization - Nested AMD event injection facelift, building on the rework of generic code and fixing a lot of corner cases - Nested AMD live migration support - Optimization for TSC deadline MSR writes and IPIs - Various cleanups - Asynchronous page fault cleanups (from tglx, common topic branch with tip tree) - Interrupt-based delivery of asynchronous "page ready" events (host side) - Hyper-V MSRs and hypercalls for guest debugging - VMX preemption timer fixes s390: - Cleanups Generic: - switch vCPU thread wakeup from swait to rcuwait The other architectures, and the guest side of the asynchronous page fault work, will come next week" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits) KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test KVM: check userspace_addr for all memslots KVM: selftests: update hyperv_cpuid with SynDBG tests x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls x86/kvm/hyper-v: enable hypercalls regardless of hypercall page x86/kvm/hyper-v: Add support for synthetic debugger interface x86/hyper-v: Add synthetic debugger definitions KVM: selftests: VMX preemption timer migration test KVM: nVMX: Fix VMX preemption timer migration x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit KVM: x86/pmu: Support full width counting KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT KVM: x86: acknowledgment mechanism for async pf page ready notifications KVM: x86: interrupt based APF 'page ready' event delivery KVM: introduce kvm_read_guest_offset_cached() KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present() KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously" KVM: VMX: Replace zero-length array with flexible-array ...

Merge branch 'for-next/scs' into for-next/core

2020-05-28T17:03:40Z

Support for Clang's Shadow Call Stack in the kernel (Sami Tolvanen and Will Deacon) * for-next/scs: arm64: entry-ftrace.S: Update comment to indicate that x18 is live scs: Move DEFINE_SCS macro into core code scs: Remove references to asm/scs.h from core code scs: Move scs_overflow_check() out of architecture code arm64: scs: Use 'scs_sp' register alias for x18 scs: Move accounting into alloc/free functions arm64: scs: Store absolute SCS stack pointer value in thread_info efi/libstub: Disable Shadow Call Stack arm64: scs: Add shadow stacks for SDEI arm64: Implement Shadow Call Stack arm64: Disable SCS for hypervisor code arm64: vdso: Disable Shadow Call Stack arm64: efi: Restore register x18 if it was corrupted arm64: Preserve register x18 when CPU is suspended arm64: Reserve register x18 from general allocation with SCS scs: Disable when function graph tracing is enabled scs: Add support for stack usage debugging scs: Add page accounting for shadow call stack allocations scs: Add support for Clang's Shadow Call Stack (SCS)