diff options
Diffstat (limited to 'virt')
-rw-r--r-- | virt/kvm/arm/vgic/vgic-its.c | 109 | ||||
-rw-r--r-- | virt/kvm/arm/vgic/vgic-mmio.c | 32 | ||||
-rw-r--r-- | virt/kvm/arm/vgic/vgic-v3.c | 5 |
3 files changed, 93 insertions, 53 deletions
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index 571b64a01c50..8d1da1af4b09 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -360,29 +360,6 @@ static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu) return ret; } -static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu, - struct vgic_its *its, - gpa_t addr, unsigned int len) -{ - u32 reg = 0; - - mutex_lock(&its->cmd_lock); - if (its->creadr == its->cwriter) - reg |= GITS_CTLR_QUIESCENT; - if (its->enabled) - reg |= GITS_CTLR_ENABLE; - mutex_unlock(&its->cmd_lock); - - return reg; -} - -static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its, - gpa_t addr, unsigned int len, - unsigned long val) -{ - its->enabled = !!(val & GITS_CTLR_ENABLE); -} - static unsigned long vgic_mmio_read_its_typer(struct kvm *kvm, struct vgic_its *its, gpa_t addr, unsigned int len) @@ -1161,33 +1138,16 @@ static void vgic_mmio_write_its_cbaser(struct kvm *kvm, struct vgic_its *its, #define ITS_CMD_SIZE 32 #define ITS_CMD_OFFSET(reg) ((reg) & GENMASK(19, 5)) -/* - * By writing to CWRITER the guest announces new commands to be processed. - * To avoid any races in the first place, we take the its_cmd lock, which - * protects our ring buffer variables, so that there is only one user - * per ITS handling commands at a given time. - */ -static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, - gpa_t addr, unsigned int len, - unsigned long val) +/* Must be called with the cmd_lock held. */ +static void vgic_its_process_commands(struct kvm *kvm, struct vgic_its *its) { gpa_t cbaser; u64 cmd_buf[4]; - u32 reg; - if (!its) - return; - - mutex_lock(&its->cmd_lock); - - reg = update_64bit_reg(its->cwriter, addr & 7, len, val); - reg = ITS_CMD_OFFSET(reg); - if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { - mutex_unlock(&its->cmd_lock); + /* Commands are only processed when the ITS is enabled. */ + if (!its->enabled) return; - } - its->cwriter = reg; cbaser = CBASER_ADDRESS(its->cbaser); while (its->cwriter != its->creadr) { @@ -1207,6 +1167,34 @@ static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, if (its->creadr == ITS_CMD_BUFFER_SIZE(its->cbaser)) its->creadr = 0; } +} + +/* + * By writing to CWRITER the guest announces new commands to be processed. + * To avoid any races in the first place, we take the its_cmd lock, which + * protects our ring buffer variables, so that there is only one user + * per ITS handling commands at a given time. + */ +static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its, + gpa_t addr, unsigned int len, + unsigned long val) +{ + u64 reg; + + if (!its) + return; + + mutex_lock(&its->cmd_lock); + + reg = update_64bit_reg(its->cwriter, addr & 7, len, val); + reg = ITS_CMD_OFFSET(reg); + if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) { + mutex_unlock(&its->cmd_lock); + return; + } + its->cwriter = reg; + + vgic_its_process_commands(kvm, its); mutex_unlock(&its->cmd_lock); } @@ -1287,6 +1275,39 @@ static void vgic_mmio_write_its_baser(struct kvm *kvm, *regptr = reg; } +static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu, + struct vgic_its *its, + gpa_t addr, unsigned int len) +{ + u32 reg = 0; + + mutex_lock(&its->cmd_lock); + if (its->creadr == its->cwriter) + reg |= GITS_CTLR_QUIESCENT; + if (its->enabled) + reg |= GITS_CTLR_ENABLE; + mutex_unlock(&its->cmd_lock); + + return reg; +} + +static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its, + gpa_t addr, unsigned int len, + unsigned long val) +{ + mutex_lock(&its->cmd_lock); + + its->enabled = !!(val & GITS_CTLR_ENABLE); + + /* + * Try to process any pending commands. This function bails out early + * if the ITS is disabled or no commands have been queued. + */ + vgic_its_process_commands(kvm, its); + + mutex_unlock(&its->cmd_lock); +} + #define REGISTER_ITS_DESC(off, rd, wr, length, acc) \ { \ .reg_offset = off, \ diff --git a/virt/kvm/arm/vgic/vgic-mmio.c b/virt/kvm/arm/vgic/vgic-mmio.c index 3654b4c835ef..2a5db1352722 100644 --- a/virt/kvm/arm/vgic/vgic-mmio.c +++ b/virt/kvm/arm/vgic/vgic-mmio.c @@ -180,21 +180,37 @@ unsigned long vgic_mmio_read_active(struct kvm_vcpu *vcpu, static void vgic_mmio_change_active(struct kvm_vcpu *vcpu, struct vgic_irq *irq, bool new_active_state) { + struct kvm_vcpu *requester_vcpu; spin_lock(&irq->irq_lock); + + /* + * The vcpu parameter here can mean multiple things depending on how + * this function is called; when handling a trap from the kernel it + * depends on the GIC version, and these functions are also called as + * part of save/restore from userspace. + * + * Therefore, we have to figure out the requester in a reliable way. + * + * When accessing VGIC state from user space, the requester_vcpu is + * NULL, which is fine, because we guarantee that no VCPUs are running + * when accessing VGIC state from user space so irq->vcpu->cpu is + * always -1. + */ + requester_vcpu = kvm_arm_get_running_vcpu(); + /* * If this virtual IRQ was written into a list register, we * have to make sure the CPU that runs the VCPU thread has - * synced back LR state to the struct vgic_irq. We can only - * know this for sure, when either this irq is not assigned to - * anyone's AP list anymore, or the VCPU thread is not - * running on any CPUs. + * synced back the LR state to the struct vgic_irq. * - * In the opposite case, we know the VCPU thread may be on its - * way back from the guest and still has to sync back this - * IRQ, so we release and re-acquire the spin_lock to let the - * other thread sync back the IRQ. + * As long as the conditions below are true, we know the VCPU thread + * may be on its way back from the guest (we kicked the VCPU thread in + * vgic_change_active_prepare) and still has to sync back this IRQ, + * so we release and re-acquire the spin_lock to let the other thread + * sync back the IRQ. */ while (irq->vcpu && /* IRQ may have state in an LR somewhere */ + irq->vcpu != requester_vcpu && /* Current thread is not the VCPU thread */ irq->vcpu->cpu != -1) /* VCPU thread is running */ cond_resched_lock(&irq->irq_lock); diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index edc6ee2dc852..be0f4c3e0142 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -229,10 +229,13 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu) /* * If we are emulating a GICv3, we do it in an non-GICv2-compatible * way, so we force SRE to 1 to demonstrate this to the guest. + * Also, we don't support any form of IRQ/FIQ bypass. * This goes with the spec allowing the value to be RAO/WI. */ if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) { - vgic_v3->vgic_sre = ICC_SRE_EL1_SRE; + vgic_v3->vgic_sre = (ICC_SRE_EL1_DIB | + ICC_SRE_EL1_DFB | + ICC_SRE_EL1_SRE); vcpu->arch.vgic_cpu.pendbaser = INITIAL_PENDBASER_VALUE; } else { vgic_v3->vgic_sre = 0; |