From c718ca0e99401d80d2480c08e1b02cf5f7cd7033 Mon Sep 17 00:00:00 2001 From: Raghavendra Rao Ananta Date: Wed, 19 Jul 2023 17:54:00 +0000 Subject: [PATCH] KVM: arm64: Fix hardware enable/disable flows for pKVM When running in protected mode, the hyp stub is disabled after pKVM is initialized, meaning the host cannot enable/disable the hyp at runtime. As such, kvm_arm_hardware_enabled is always 1 after initialization, and kvm_arch_hardware_enable() never enables the vgic maintenance irq or timer irqs. Unconditionally enable/disable the vgic + timer irqs in the respective calls, instead relying on the percpu bookkeeping in the generic code to keep track of which cpus have the interrupts unmasked. Fixes: 466d27e48d7c ("KVM: arm64: Simplify the CPUHP logic") Reported-by: Oliver Upton Suggested-by: Oliver Upton Signed-off-by: Raghavendra Rao Ananta Link: https://lore.kernel.org/r/20230719175400.647154-1-rananta@google.com Acked-by: Marc Zyngier Signed-off-by: Oliver Upton --- arch/arm64/kvm/arm.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 72dc53a7..d854056 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1874,8 +1874,6 @@ static void _kvm_arch_hardware_enable(void *discard) int kvm_arch_hardware_enable(void) { - int was_enabled; - /* * Most calls to this function are made with migration * disabled, but not with preemption disabled. The former is @@ -1884,13 +1882,10 @@ int kvm_arch_hardware_enable(void) */ preempt_disable(); - was_enabled = __this_cpu_read(kvm_arm_hardware_enabled); _kvm_arch_hardware_enable(NULL); - if (!was_enabled) { - kvm_vgic_cpu_up(); - kvm_timer_cpu_up(); - } + kvm_vgic_cpu_up(); + kvm_timer_cpu_up(); preempt_enable(); @@ -1907,10 +1902,8 @@ static void _kvm_arch_hardware_disable(void *discard) void kvm_arch_hardware_disable(void) { - if (__this_cpu_read(kvm_arm_hardware_enabled)) { - kvm_timer_cpu_down(); - kvm_vgic_cpu_down(); - } + kvm_timer_cpu_down(); + kvm_vgic_cpu_down(); if (!is_protected_kvm_enabled()) _kvm_arch_hardware_disable(NULL); -- 2.7.4