kernel/arch/arm64/kvm/arch_timer.c, branch linux-6.2.y

Merge branch kvm-arm64/burn-the-flags into kvmarm-master/next

2022-06-29T09:30:10Z

* kvm-arm64/burn-the-flags: : . : Rework the per-vcpu flags to make them more manageable, : splitting them in different sets that have specific : uses: : : - configuration flags : - input to the world-switch : - state bookkeeping for the kernel itself : : The FP tracking is also simplified and tracked outside : of the flags as a separate state. : . KVM: arm64: Move the handling of !FP outside of the fast path KVM: arm64: Document why pause cannot be turned into a flag KVM: arm64: Reduce the size of the vcpu flag members KVM: arm64: Add build-time sanity checks for flags KVM: arm64: Warn when PENDING_EXCEPTION and INCREMENT_PC are set together KVM: arm64: Convert vcpu sysregs_loaded_on_cpu to a state flag KVM: arm64: Kill unused vcpu flags field KVM: arm64: Move vcpu WFIT flag to the state flag set KVM: arm64: Move vcpu ON_UNSUPPORTED_CPU flag to the state flag set KVM: arm64: Move vcpu SVE/SME flags to the state flag set KVM: arm64: Move vcpu debug/SPE/TRBE flags to the input flag set KVM: arm64: Move vcpu PC/Exception flags to the input flag set KVM: arm64: Move vcpu configuration flags into their own set KVM: arm64: Add three sets of flags to the vcpu state KVM: arm64: Add helpers to manipulate vcpu flags among a set KVM: arm64: Move FP state ownership from flag to a tristate KVM: arm64: Drop FP_FOREIGN_STATE from the hypervisor code Signed-off-by: Marc Zyngier

KVM: arm64: Move vcpu WFIT flag to the state flag set

2022-06-29T09:23:23Z

The host kernel uses the WFIT flag to remember that a vcpu has used this instruction and wake it up as required. Move it to the state set, as nothing in the hypervisor uses this information. Reviewed-by: Fuad Tabba Reviewed-by: Reiji Watanabe Signed-off-by: Marc Zyngier

KVM: arm64: Warn if accessing timer pending state outside of vcpu context

2022-06-08T09:16:23Z

A recurrent bug in the KVM/arm64 code base consists in trying to access the timer pending state outside of the vcpu context, which makes zero sense (the pending state only exists when the vcpu is loaded). In order to avoid more embarassing crashes and catch the offenders red-handed, add a warning to kvm_arch_timer_get_input_level() and return the state as non-pending. This avoids taking the system down, and still helps tracking down silly bugs. Reviewed-by: Eric Auger Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220607131427.1164881-4-maz@kernel.org

KVM: arm64: Handle blocking WFIT instruction

2022-04-20T12:24:45Z

When trapping a blocking WFIT instruction, take it into account when computing the deadline of the background timer. The state is tracked with a new vcpu flag, and is gated by a new CPU capability, which isn't currently enabled. Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220419182755.601427-6-maz@kernel.org

KVM: arm64: Introduce kvm_counter_compute_delta() helper

2022-04-20T12:24:44Z

Refactor kvm_timer_compute_delta() and extract a helper that compute the delta (in ns) between a given timer and an arbitrary value. No functional change expected. Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220419182755.601427-5-maz@kernel.org

KVM: arm64: Simplify kvm_cpu_has_pending_timer()

2022-04-20T12:24:44Z

kvm_cpu_has_pending_timer() ends up checking all the possible timers for a wake-up cause. However, we already check for pending interrupts whenever we try to wake-up a vcpu, including the timer interrupts. Obviously, doing the same work twice is once too many. Reduce this helper to almost nothing, but keep it around, as we are going to make use of it soon. Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220419182755.601427-4-maz@kernel.org

KVM: Add helpers to wake/query blocking vCPU

2021-12-08T09:24:54Z

Add helpers to wake and query a blocking vCPU. In addition to providing nice names, the helpers reduce the probability of KVM neglecting to use kvm_arch_vcpu_get_wait(). No functional change intended. Signed-off-by: Sean Christopherson Message-Id: <20211009021236.4122790-20-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: Rename kvm_vcpu_block() => kvm_vcpu_halt()

2021-12-08T09:24:51Z

Rename kvm_vcpu_block() to kvm_vcpu_halt() in preparation for splitting the actual "block" sequences into a separate helper (to be named kvm_vcpu_block()). x86 will use the standalone block-only path to handle non-halt cases where the vCPU is not runnable. Rename block_ns to halt_ns to match the new function name. No functional change intended. Reviewed-by: David Matlack Reviewed-by: Christian Borntraeger Signed-off-by: Sean Christopherson Message-Id: <20211009021236.4122790-14-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: Use 'unsigned long' as kvm_for_each_vcpu()'s index

2021-12-08T09:24:15Z

Everywhere we use kvm_for_each_vpcu(), we use an int as the vcpu index. Unfortunately, we're about to move rework the iterator, which requires this to be upgrade to an unsigned long. Let's bite the bullet and repaint all of it in one go. Signed-off-by: Marc Zyngier Message-Id: <20211116160403.4074052-7-maz@kernel.org> Signed-off-by: Paolo Bonzini

KVM: arm64: timer: Add support for SW-based deactivation

2021-06-01T09:46:00Z

In order to deal with the lack of active state, we need to use the mask/unmask primitives (after all, the active state is just an additional mask on top of the normal one). To avoid adding a bunch of ugly conditionals in the timer and vgic code, let's use a timer-specific irqdomain to deal with the state conversion. Yes, this is an unexpected use of irqdomains, but there is no reason not to be just as creative as the designers of the HW... This involves overloading the vcpu_affinity, set_irqchip_state and eoi callbacks so that the rest of the KVM code can continue ignoring the oddities of the underlying platform. Signed-off-by: Marc Zyngier