linux-dev/arch/arm64/kvm/arch_timer.c, branch linus/master

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

KVM: arm64: timer: Refactor IRQ configuration

2021-06-01T09:46:00Z

As we are about to add some more things to the timer IRQ configuration, move this code out of the main timer init code into its own set of functions. No functional changes. Signed-off-by: Marc Zyngier

KVM: arm64: vgic: move irq->get_input_level into an ops structure

2021-06-01T09:45:59Z

We already have the option to attach a callback to an interrupt to retrieve its pending state. As we are planning to expand this facility, move this callback into its own data structure. This will limit the size of individual interrupts as the ops structures can be shared across multiple interrupts. Signed-off-by: Marc Zyngier