Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'vfio-v4.14-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Base MSI remapping on either IOMMU domain or IRQ domain support
(Robin Murphy)
- Prioritize hardware MSI regions over software defined regions (Robin
Murphy)
- Fix no-iommu reference counting (Eric Auger)
- Stall removing last device from group for container cleanup (Alex
Williamson)
- Constify amba_id (Arvind Yadav)
* tag 'vfio-v4.14-rc1' of git://github.com/awilliam/linux-vfio:
vfio: platform: constify amba_id
vfio: Stall vfio_del_group_dev() for container group detach
vfio: fix noiommu vfio_iommu_group_get reference count
vfio/type1: Give hardware MSI regions precedence
vfio/type1: Cope with hardware MSI reserved regions
+36
-7
+1
-1
drivers/vfio/platform/vfio_amba.c
+1
-1
drivers/vfio/platform/vfio_amba.c
+23
-2
drivers/vfio/vfio.c
+23
-2
drivers/vfio/vfio.c
···
85
85
struct list_head unbound_list;
86
86
struct mutex unbound_lock;
87
87
atomic_t opened;
88
+
wait_queue_head_t container_q;
88
89
bool noiommu;
89
90
struct kvm *kvm;
90
91
struct blocking_notifier_head notifier;
···
139
138
iommu_group_set_name(group, "vfio-noiommu");
140
139
iommu_group_set_iommudata(group, &noiommu, NULL);
141
140
ret = iommu_group_add_device(group, dev);
142
-
iommu_group_put(group);
143
-
if (ret)
141
+
if (ret) {
142
+
iommu_group_put(group);
144
143
return NULL;
144
+
}
145
145
146
146
/*
147
147
* Where to taint? At this point we've added an IOMMU group for a
···
339
337
mutex_init(&group->unbound_lock);
340
338
atomic_set(&group->container_users, 0);
341
339
atomic_set(&group->opened, 0);
340
+
init_waitqueue_head(&group->container_q);
342
341
group->iommu_group = iommu_group;
343
342
#ifdef CONFIG_VFIO_NOIOMMU
344
343
group->noiommu = (iommu_group_get_iommudata(iommu_group) == &noiommu);
···
996
993
}
997
994
} while (ret <= 0);
998
995
996
+
/*
997
+
* In order to support multiple devices per group, devices can be
998
+
* plucked from the group while other devices in the group are still
999
+
* in use. The container persists with this group and those remaining
1000
+
* devices still attached. If the user creates an isolation violation
1001
+
* by binding this device to another driver while the group is still in
1002
+
* use, that's their fault. However, in the case of removing the last,
1003
+
* or potentially the only, device in the group there can be no other
1004
+
* in-use devices in the group. The user has done their due diligence
1005
+
* and we should lay no claims to those devices. In order to do that,
1006
+
* we need to make sure the group is detached from the container.
1007
+
* Without this stall, we're potentially racing with a user process
1008
+
* that may attempt to immediately bind this device to another driver.
1009
+
*/
1010
+
if (list_empty(&group->device_list))
1011
+
wait_event(group->container_q, !group->container);
1012
+
999
1013
vfio_group_put(group);
1000
1014
1001
1015
return device_data;
···
1318
1298
group->iommu_group);
1319
1299
1320
1300
group->container = NULL;
1301
+
wake_up(&group->container_q);
1321
1302
list_del(&group->container_next);
1322
1303
1323
1304
/* Detaching the last group deprivileges a container, remove iommu */
+12
-4
drivers/vfio/vfio_iommu_type1.c
+12
-4
drivers/vfio/vfio_iommu_type1.c
···
1169
1169
INIT_LIST_HEAD(&group_resv_regions);
1170
1170
iommu_get_group_resv_regions(group, &group_resv_regions);
1171
1171
list_for_each_entry(region, &group_resv_regions, list) {
1172
+
/*
1173
+
* The presence of any 'real' MSI regions should take
1174
+
* precedence over the software-managed one if the
1175
+
* IOMMU driver happens to advertise both types.
1176
+
*/
1177
+
if (region->type == IOMMU_RESV_MSI) {
1178
+
ret = false;
1179
+
break;
1180
+
}
1181
+
1172
1182
if (region->type == IOMMU_RESV_SW_MSI) {
1173
1183
*base = region->start;
1174
1184
ret = true;
1175
-
goto out;
1176
1185
}
1177
1186
}
1178
-
out:
1179
1187
list_for_each_entry_safe(region, next, &group_resv_regions, list)
1180
1188
kfree(region);
1181
1189
return ret;
···
1273
1265
INIT_LIST_HEAD(&domain->group_list);
1274
1266
list_add(&group->next, &domain->group_list);
1275
1267
1276
-
msi_remap = resv_msi ? irq_domain_check_msi_remap() :
1277
-
iommu_capable(bus, IOMMU_CAP_INTR_REMAP);
1268
+
msi_remap = irq_domain_check_msi_remap() ||
1269
+
iommu_capable(bus, IOMMU_CAP_INTR_REMAP);
1278
1270
1279
1271
if (!allow_unsafe_interrupts && !msi_remap) {
1280
1272
pr_warn("%s: No interrupt remapping support. Use the module param \"allow_unsafe_interrupts\" to enable VFIO IOMMU support on this platform\n",