summaryrefslogtreecommitdiffstats
path: root/drivers/iommu/amd/iommu.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/iommu/amd/iommu.c')
-rw-r--r--drivers/iommu/amd/iommu.c26
1 files changed, 21 insertions, 5 deletions
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index ba9f3dbc5b94..07ae8b93887e 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2659,7 +2659,12 @@ static int amd_iommu_def_domain_type(struct device *dev)
if (!dev_data)
return 0;
- if (dev_data->iommu_v2)
+ /*
+ * Do not identity map IOMMUv2 capable devices when memory encryption is
+ * active, because some of those devices (AMD GPUs) don't have the
+ * encryption bit in their DMA-mask and require remapping.
+ */
+ if (!mem_encrypt_active() && dev_data->iommu_v2)
return IOMMU_DOMAIN_IDENTITY;
return 0;
@@ -3292,6 +3297,7 @@ out:
static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte,
struct amd_ir_data *data)
{
+ bool ret;
struct irq_remap_table *table;
struct amd_iommu *iommu;
unsigned long flags;
@@ -3309,10 +3315,18 @@ static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte,
entry = (struct irte_ga *)table->table;
entry = &entry[index];
- entry->lo.fields_remap.valid = 0;
- entry->hi.val = irte->hi.val;
- entry->lo.val = irte->lo.val;
- entry->lo.fields_remap.valid = 1;
+
+ ret = cmpxchg_double(&entry->lo.val, &entry->hi.val,
+ entry->lo.val, entry->hi.val,
+ irte->lo.val, irte->hi.val);
+ /*
+ * We use cmpxchg16 to atomically update the 128-bit IRTE,
+ * and it cannot be updated by the hardware or other processors
+ * behind us, so the return value of cmpxchg16 should be the
+ * same as the old value.
+ */
+ WARN_ON(!ret);
+
if (data)
data->ref = entry;
@@ -3850,6 +3864,7 @@ int amd_iommu_deactivate_guest_mode(void *data)
struct amd_ir_data *ir_data = (struct amd_ir_data *)data;
struct irte_ga *entry = (struct irte_ga *) ir_data->entry;
struct irq_cfg *cfg = ir_data->cfg;
+ u64 valid = entry->lo.fields_remap.valid;
if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) ||
!entry || !entry->lo.fields_vapic.guest_mode)
@@ -3858,6 +3873,7 @@ int amd_iommu_deactivate_guest_mode(void *data)
entry->lo.val = 0;
entry->hi.val = 0;
+ entry->lo.fields_remap.valid = valid;
entry->lo.fields_remap.dm = apic->irq_dest_mode;
entry->lo.fields_remap.int_type = apic->irq_delivery_mode;
entry->hi.fields.vector = cfg->vector;