From 1fcf7ce0c60213994269fb59569ec161eb6e08d6 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Mon, 5 Aug 2013 15:04:46 +0100 Subject: arm: kvm: implement CPU PM notifier Upon CPU shutdown and consequent warm-reboot, the hypervisor CPU state must be re-initialized. This patch implements a CPU PM notifier that upon warm-boot calls a KVM hook to reinitialize properly the hypervisor state so that the CPU can be safely resumed. Acked-by: Marc Zyngier Acked-by: Christoffer Dall Signed-off-by: Lorenzo Pieralisi --- arch/arm/kvm/arm.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 2a700e00528d..b18165ca1d38 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -17,6 +17,7 @@ */ #include +#include #include #include #include @@ -853,6 +854,33 @@ static struct notifier_block hyp_init_cpu_nb = { .notifier_call = hyp_init_cpu_notify, }; +#ifdef CONFIG_CPU_PM +static int hyp_init_cpu_pm_notifier(struct notifier_block *self, + unsigned long cmd, + void *v) +{ + if (cmd == CPU_PM_EXIT) { + cpu_init_hyp_mode(NULL); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static struct notifier_block hyp_init_cpu_pm_nb = { + .notifier_call = hyp_init_cpu_pm_notifier, +}; + +static void __init hyp_cpu_pm_init(void) +{ + cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); +} +#else +static inline void hyp_cpu_pm_init(void) +{ +} +#endif + /** * Inits Hyp-mode on all online CPUs */ @@ -1013,6 +1041,8 @@ int kvm_arch_init(void *opaque) goto out_err; } + hyp_cpu_pm_init(); + kvm_coproc_table_init(); return 0; out_err: -- cgit v1.2.3 From 478a8237f656d86d25b3e4e4bf3c48f590156294 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 19 Nov 2013 17:43:19 -0800 Subject: arm: KVM: Don't return PSCI_INVAL if waitqueue is inactive The current KVM implementation of PSCI returns INVALID_PARAMETERS if the waitqueue for the corresponding CPU is not active. This does not seem correct, since KVM should not care what the specific thread is doing, for example, user space may not have called KVM_RUN on this VCPU yet or the thread may be busy looping to user space because it received a signal; this is really up to the user space implementation. Instead we should check specifically that the CPU is marked as being turned off, regardless of the VCPU thread state, and if it is, we shall simply clear the pause flag on the CPU and wake up the thread if it happens to be blocked for us. Further, the implementation seems to be racy when executing multiple VCPU threads. There really isn't a reasonable user space programming scheme to ensure all secondary CPUs have reached kvm_vcpu_first_run_init before turning on the boot CPU. Therefore, set the pause flag on the vcpu at VCPU init time (which can reasonably be expected to be completed for all CPUs by user space before running any VCPUs) and clear both this flag and the feature (in case the feature can somehow get set again in the future) and ping the waitqueue on turning on a VCPU using PSCI. Reported-by: Peter Maydell Signed-off-by: Christoffer Dall --- arch/arm/kvm/arm.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 2a700e00528d..151eb9160482 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -478,15 +478,6 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) return ret; } - /* - * Handle the "start in power-off" case by calling into the - * PSCI code. - */ - if (test_and_clear_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) { - *vcpu_reg(vcpu, 0) = KVM_PSCI_FN_CPU_OFF; - kvm_psci_call(vcpu); - } - return 0; } @@ -700,6 +691,24 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, return -EINVAL; } +static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, + struct kvm_vcpu_init *init) +{ + int ret; + + ret = kvm_vcpu_set_target(vcpu, init); + if (ret) + return ret; + + /* + * Handle the "start in power-off" case by marking the VCPU as paused. + */ + if (__test_and_clear_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) + vcpu->arch.pause = true; + + return 0; +} + long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -713,8 +722,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp, if (copy_from_user(&init, argp, sizeof(init))) return -EFAULT; - return kvm_vcpu_set_target(vcpu, &init); - + return kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); } case KVM_SET_ONE_REG: case KVM_GET_ONE_REG: { -- cgit v1.2.3 From a1a64387adeeba7a34ce06f2774e81f496ee803b Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Sat, 16 Nov 2013 10:51:25 -0800 Subject: arm/arm64: KVM: arch_timer: Initialize cntvoff at kvm_init Initialize the cntvoff at kvm_init_vm time, not before running the VCPUs at the first time because that will overwrite any potentially restored values from user space. Cc: Andre Przywara Acked-by: Marc Zynger Signed-off-by: Christoffer Dall --- arch/arm/kvm/arm.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 2a700e00528d..13205bd9b359 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -137,6 +137,8 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) if (ret) goto out_free_stage2_pgd; + kvm_timer_init(kvm); + /* Mark the initial VMID generation invalid */ kvm->arch.vmid_gen = 0; -- cgit v1.2.3 From e1ba0207a1b3714bb3f000e506285ae5123cdfa7 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Mon, 23 Sep 2013 14:55:55 -0700 Subject: ARM: KVM: Allow creating the VGIC after VCPUs Rework the VGIC initialization slightly to allow initialization of the vgic cpu-specific state even if the irqchip (the VGIC) hasn't been created by user space yet. This is safe, because the vgic data structures are already allocated when the CPU is allocated if VGIC support is compiled into the kernel. Further, the init process does not depend on any other information and the sacrifice is a slight performance degradation for creating VMs in the no-VGIC case. The reason is that the new device control API doesn't mandate creating the VGIC before creating the VCPU and it is unreasonable to require user space to create the VGIC before creating the VCPUs. At the same time move the irqchip_in_kernel check out of kvm_vcpu_first_run_init and into the init function to make the per-vcpu and global init functions symmetric and add comments on the exported functions making it a bit easier to understand the init flow by only looking at vgic.c. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/arm.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 13205bd9b359..c9fe9d71be73 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -464,6 +464,8 @@ static void update_vttbr(struct kvm *kvm) static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) { + int ret; + if (likely(vcpu->arch.has_run_once)) return 0; @@ -473,9 +475,8 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) * Initialize the VGIC before running a vcpu the first time on * this VM. */ - if (irqchip_in_kernel(vcpu->kvm) && - unlikely(!vgic_initialized(vcpu->kvm))) { - int ret = kvm_vgic_init(vcpu->kvm); + if (unlikely(!vgic_initialized(vcpu->kvm))) { + ret = kvm_vgic_init(vcpu->kvm); if (ret) return ret; } -- cgit v1.2.3 From 7330672befe6269e575f79b924a7068b26c144b4 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Fri, 25 Oct 2013 17:29:18 +0100 Subject: KVM: arm-vgic: Support KVM_CREATE_DEVICE for VGIC Support creating the ARM VGIC device through the KVM_CREATE_DEVICE ioctl, which can then later be leveraged to use the KVM_{GET/SET}_DEVICE_ATTR, which is useful both for setting addresses in a more generic API than the ARM-specific one and is useful for save/restore of VGIC state. Adds KVM_CAP_DEVICE_CTRL to ARM capabilities. Note that we change the check for creating a VGIC from bailing out if any VCPUs were created, to bailing out if any VCPUs were ever run. This is an important distinction that shouldn't break anything, but allows creating the VGIC after the VCPUs have been created. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/arm.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index c9fe9d71be73..cc7c41af9c38 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -190,6 +190,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_IRQCHIP: r = vgic_present; break; + case KVM_CAP_DEVICE_CTRL: case KVM_CAP_USER_MEMORY: case KVM_CAP_SYNC_MMU: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: -- cgit v1.2.3 From ce01e4e8874d410738f4b4733b26642d6611a331 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Mon, 23 Sep 2013 14:55:56 -0700 Subject: KVM: arm-vgic: Set base addr through device API Support setting the distributor and cpu interface base addresses in the VM physical address space through the KVM_{SET,GET}_DEVICE_ATTR API in addition to the ARM specific API. This has the added benefit of being able to share more code in user space and do things in a uniform manner. Also deprecate the older API at the same time, but backwards compatibility will be maintained. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/arm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index cc7c41af9c38..f290b2250ed5 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -776,7 +776,7 @@ static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, case KVM_ARM_DEVICE_VGIC_V2: if (!vgic_present) return -ENXIO; - return kvm_vgic_set_addr(kvm, type, dev_addr->addr); + return kvm_vgic_addr(kvm, type, &dev_addr->addr, true); default: return -ENODEV; } -- cgit v1.2.3 From e9b152cb957cb194437f37e79f0f3c9d34fe53d6 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Wed, 11 Dec 2013 20:29:11 -0800 Subject: arm/arm64: kvm: Set vcpu->cpu to -1 on vcpu_put The arch-generic KVM code expects the cpu field of a vcpu to be -1 if the vcpu is no longer assigned to a cpu. This is used for the optimized make_all_cpus_request path and will be used by the vgic code to check that no vcpus are running. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/arm.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/arm/kvm/arm.c') diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index f290b2250ed5..b92ff6d3e34b 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -342,6 +342,13 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { + /* + * The arch-generic KVM code expects the cpu field of a vcpu to be -1 + * if the vcpu is no longer assigned to a cpu. This is used for the + * optimized make_all_cpus_request path. + */ + vcpu->cpu = -1; + kvm_arm_set_running_vcpu(NULL); } -- cgit v1.2.3