arm/arm64: KVM: vgic: Fix SGI writes to GICD_I{CS}PENDR0

Writes to GICD_ISPENDR0 and GICD_ICPENDR0 ignore all settings of the
pending state for SGIs.  Make sure the implementation handles this
correctly.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 435d8e7ad13721d722ebf839110327876f7cc51c..0039ae266a7b44d6bc256eb552e865234c33ccd1 100644 (file)
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -454,7 +454,7 @@ static bool handle_mmio_set_pending_reg(struct kvm_vcpu *vcpu,
                                        struct kvm_exit_mmio *mmio,
                                        phys_addr_t offset)
 {
-       u32 *reg;
+       u32 *reg, orig;
        u32 level_mask;
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
 
@@ -463,6 +463,7 @@ static bool handle_mmio_set_pending_reg(struct kvm_vcpu *vcpu,
 
        /* Mark both level and edge triggered irqs as pending */
        reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu->vcpu_id, offset);
+       orig = *reg;
        vgic_reg_access(mmio, reg, offset,
                        ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
 
@@ -474,6 +475,12 @@ static bool handle_mmio_set_pending_reg(struct kvm_vcpu *vcpu,
                                ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
                *reg &= level_mask;
 
+               /* Ignore writes to SGIs */
+               if (offset < 2) {
+                       *reg &= ~0xffff;
+                       *reg |= orig & 0xffff;
+               }
+
                vgic_update_state(vcpu->kvm);
                return true;
        }
@@ -486,10 +493,11 @@ static bool handle_mmio_clear_pending_reg(struct kvm_vcpu *vcpu,
                                          phys_addr_t offset)
 {
        u32 *level_active;
-       u32 *reg;
+       u32 *reg, orig;
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
 
        reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu->vcpu_id, offset);
+       orig = *reg;
        vgic_reg_access(mmio, reg, offset,
                        ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
        if (mmio->is_write) {
@@ -500,6 +508,12 @@ static bool handle_mmio_clear_pending_reg(struct kvm_vcpu *vcpu,
                                          vcpu->vcpu_id, offset);
                *reg |= *level_active;
 
+               /* Ignore writes to SGIs */
+               if (offset < 2) {
+                       *reg &= ~0xffff;
+                       *reg |= orig & 0xffff;
+               }
+
                /* Clear soft-pending flags */
                reg = vgic_bitmap_get_reg(&dist->irq_soft_pend,
                                          vcpu->vcpu_id, offset);