diff options
-rw-r--r-- | include/linux/kvm_host.h | 4 | ||||
-rw-r--r-- | virt/kvm/coalesced_mmio.c | 19 | ||||
-rw-r--r-- | virt/kvm/kvm_main.c | 10 |
3 files changed, 24 insertions, 9 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7f2e2a09ebbd..a2278b9ff57d 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -190,8 +190,8 @@ int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr, int len, void *val); int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, int len, 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 kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, + struct kvm_io_device *dev); struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr); diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c index e2c197fd4f9d..6edfcf1f3bd6 100644 --- a/virt/kvm/coalesced_mmio.c +++ b/virt/kvm/coalesced_mmio.c @@ -174,21 +174,36 @@ int kvm_vm_ioctl_unregister_coalesced_mmio(struct kvm *kvm, struct kvm_coalesced_mmio_zone *zone) { struct kvm_coalesced_mmio_dev *dev, *tmp; + int r; if (zone->pio != 1 && zone->pio != 0) return -EINVAL; mutex_lock(&kvm->slots_lock); - list_for_each_entry_safe(dev, tmp, &kvm->coalesced_zones, list) + list_for_each_entry_safe(dev, tmp, &kvm->coalesced_zones, list) { if (zone->pio == dev->zone.pio && coalesced_mmio_in_range(dev, zone->addr, zone->size)) { - kvm_io_bus_unregister_dev(kvm, + r = kvm_io_bus_unregister_dev(kvm, zone->pio ? KVM_PIO_BUS : KVM_MMIO_BUS, &dev->dev); kvm_iodevice_destructor(&dev->dev); + + /* + * On failure, unregister destroys all devices on the + * bus _except_ the target device, i.e. coalesced_zones + * has been modified. No need to restart the walk as + * there aren't any zones left. + */ + if (r) + break; } + } mutex_unlock(&kvm->slots_lock); + /* + * Ignore the result of kvm_io_bus_unregister_dev(), from userspace's + * perspective, the coalesced MMIO is most definitely unregistered. + */ return 0; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1b643003f0bc..78bf3f549214 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4342,15 +4342,15 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, } /* Caller must hold slots_lock. */ -void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, - struct kvm_io_device *dev) +int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, + struct kvm_io_device *dev) { int i, j; struct kvm_io_bus *new_bus, *bus; bus = kvm_get_bus(kvm, bus_idx); if (!bus) - return; + return 0; for (i = 0; i < bus->dev_count; i++) if (bus->range[i].dev == dev) { @@ -4358,7 +4358,7 @@ void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, } if (i == bus->dev_count) - return; + return 0; new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1), GFP_KERNEL_ACCOUNT); @@ -4383,7 +4383,7 @@ void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, } kfree(bus); - return; + return new_bus ? 0 : -ENOMEM; } struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, |