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-rw-r--r--virt/kvm/arm/vgic/vgic-its.c109
-rw-r--r--virt/kvm/arm/vgic/vgic-mmio.c32
-rw-r--r--virt/kvm/arm/vgic/vgic-v3.c5
-rw-r--r--virt/kvm/eventfd.c3
-rw-r--r--virt/kvm/kvm_main.c44
5 files changed, 126 insertions, 67 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;
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index a29786dd9522..4d28a9ddbee0 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -870,7 +870,8 @@ kvm_deassign_ioeventfd_idx(struct kvm *kvm, enum kvm_bus bus_idx,
continue;
kvm_io_bus_unregister_dev(kvm, bus_idx, &p->dev);
- kvm->buses[bus_idx]->ioeventfd_count--;
+ if (kvm->buses[bus_idx])
+ kvm->buses[bus_idx]->ioeventfd_count--;
ioeventfd_release(p);
ret = 0;
break;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index a17d78759727..88257b311cb5 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -727,8 +727,11 @@ static void kvm_destroy_vm(struct kvm *kvm)
list_del(&kvm->vm_list);
spin_unlock(&kvm_lock);
kvm_free_irq_routing(kvm);
- for (i = 0; i < KVM_NR_BUSES; i++)
- kvm_io_bus_destroy(kvm->buses[i]);
+ for (i = 0; i < KVM_NR_BUSES; i++) {
+ if (kvm->buses[i])
+ kvm_io_bus_destroy(kvm->buses[i]);
+ kvm->buses[i] = NULL;
+ }
kvm_coalesced_mmio_free(kvm);
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
@@ -1062,7 +1065,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
* changes) is disallowed above, so any other attribute changes getting
* here can be skipped.
*/
- if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
+ if (as_id == 0 && (change == KVM_MR_CREATE || change == KVM_MR_MOVE)) {
r = kvm_iommu_map_pages(kvm, &new);
return r;
}
@@ -3474,6 +3477,8 @@ int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
};
bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
+ if (!bus)
+ return -ENOMEM;
r = __kvm_io_bus_write(vcpu, bus, &range, val);
return r < 0 ? r : 0;
}
@@ -3491,6 +3496,8 @@ int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
};
bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
+ if (!bus)
+ return -ENOMEM;
/* First try the device referenced by cookie. */
if ((cookie >= 0) && (cookie < bus->dev_count) &&
@@ -3541,6 +3548,8 @@ int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
};
bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
+ if (!bus)
+ return -ENOMEM;
r = __kvm_io_bus_read(vcpu, bus, &range, val);
return r < 0 ? r : 0;
}
@@ -3553,6 +3562,9 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
struct kvm_io_bus *new_bus, *bus;
bus = kvm->buses[bus_idx];
+ if (!bus)
+ return -ENOMEM;
+
/* exclude ioeventfd which is limited by maximum fd */
if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
return -ENOSPC;
@@ -3572,37 +3584,41 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
}
/* Caller must hold slots_lock. */
-int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
- struct kvm_io_device *dev)
+void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
+ struct kvm_io_device *dev)
{
- int i, r;
+ int i;
struct kvm_io_bus *new_bus, *bus;
bus = kvm->buses[bus_idx];
- r = -ENOENT;
+ if (!bus)
+ return;
+
for (i = 0; i < bus->dev_count; i++)
if (bus->range[i].dev == dev) {
- r = 0;
break;
}
- if (r)
- return r;
+ if (i == bus->dev_count)
+ return;
new_bus = kmalloc(sizeof(*bus) + ((bus->dev_count - 1) *
sizeof(struct kvm_io_range)), GFP_KERNEL);
- if (!new_bus)
- return -ENOMEM;
+ if (!new_bus) {
+ pr_err("kvm: failed to shrink bus, removing it completely\n");
+ goto broken;
+ }
memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
new_bus->dev_count--;
memcpy(new_bus->range + i, bus->range + i + 1,
(new_bus->dev_count - i) * sizeof(struct kvm_io_range));
+broken:
rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
synchronize_srcu_expedited(&kvm->srcu);
kfree(bus);
- return r;
+ return;
}
struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx,
@@ -3615,6 +3631,8 @@ struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx,
srcu_idx = srcu_read_lock(&kvm->srcu);
bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
+ if (!bus)
+ goto out_unlock;
dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1);
if (dev_idx < 0)
generated by cgit (git 2.34.1) at 2024-05-28 12:24:30 +0000