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-rw-r--r--drivers/iommu/dmar.c25
-rw-r--r--drivers/iommu/intel-iommu.c53
-rw-r--r--include/linux/dmar.h8
3 files changed, 84 insertions, 2 deletions
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index d9c748b6f9e4..1edf2a251336 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -2042,3 +2042,28 @@ int dmar_device_remove(acpi_handle handle)
{
return dmar_device_hotplug(handle, false);
}
+
+/*
+ * dmar_platform_optin - Is %DMA_CTRL_PLATFORM_OPT_IN_FLAG set in DMAR table
+ *
+ * Returns true if the platform has %DMA_CTRL_PLATFORM_OPT_IN_FLAG set in
+ * the ACPI DMAR table. This means that the platform boot firmware has made
+ * sure no device can issue DMA outside of RMRR regions.
+ */
+bool dmar_platform_optin(void)
+{
+ struct acpi_table_dmar *dmar;
+ acpi_status status;
+ bool ret;
+
+ status = acpi_get_table(ACPI_SIG_DMAR, 0,
+ (struct acpi_table_header **)&dmar);
+ if (ACPI_FAILURE(status))
+ return false;
+
+ ret = !!(dmar->flags & DMAR_PLATFORM_OPT_IN);
+ acpi_put_table((struct acpi_table_header *)dmar);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dmar_platform_optin);
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 41a4b8808802..30e8584137f5 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -184,6 +184,7 @@ static int rwbf_quirk;
*/
static int force_on = 0;
int intel_iommu_tboot_noforce;
+static int no_platform_optin;
#define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry))
@@ -503,6 +504,7 @@ static int __init intel_iommu_setup(char *str)
pr_info("IOMMU enabled\n");
} else if (!strncmp(str, "off", 3)) {
dmar_disabled = 1;
+ no_platform_optin = 1;
pr_info("IOMMU disabled\n");
} else if (!strncmp(str, "igfx_off", 8)) {
dmar_map_gfx = 0;
@@ -2895,6 +2897,13 @@ static int iommu_should_identity_map(struct device *dev, int startup)
if (device_is_rmrr_locked(dev))
return 0;
+ /*
+ * Prevent any device marked as untrusted from getting
+ * placed into the statically identity mapping domain.
+ */
+ if (pdev->untrusted)
+ return 0;
+
if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
return 1;
@@ -4728,14 +4737,54 @@ const struct attribute_group *intel_iommu_groups[] = {
NULL,
};
+static int __init platform_optin_force_iommu(void)
+{
+ struct pci_dev *pdev = NULL;
+ bool has_untrusted_dev = false;
+
+ if (!dmar_platform_optin() || no_platform_optin)
+ return 0;
+
+ for_each_pci_dev(pdev) {
+ if (pdev->untrusted) {
+ has_untrusted_dev = true;
+ break;
+ }
+ }
+
+ if (!has_untrusted_dev)
+ return 0;
+
+ if (no_iommu || dmar_disabled)
+ pr_info("Intel-IOMMU force enabled due to platform opt in\n");
+
+ /*
+ * If Intel-IOMMU is disabled by default, we will apply identity
+ * map for all devices except those marked as being untrusted.
+ */
+ if (dmar_disabled)
+ iommu_identity_mapping |= IDENTMAP_ALL;
+
+ dmar_disabled = 0;
+#if defined(CONFIG_X86) && defined(CONFIG_SWIOTLB)
+ swiotlb = 0;
+#endif
+ no_iommu = 0;
+
+ return 1;
+}
+
int __init intel_iommu_init(void)
{
int ret = -ENODEV;
struct dmar_drhd_unit *drhd;
struct intel_iommu *iommu;
- /* VT-d is required for a TXT/tboot launch, so enforce that */
- force_on = tboot_force_iommu();
+ /*
+ * Intel IOMMU is required for a TXT/tboot launch or platform
+ * opt in, so enforce that.
+ */
+ force_on = tboot_force_iommu() || platform_optin_force_iommu();
if (iommu_init_mempool()) {
if (force_on)
diff --git a/include/linux/dmar.h b/include/linux/dmar.h
index 843a41ba7e28..f8af1d770520 100644
--- a/include/linux/dmar.h
+++ b/include/linux/dmar.h
@@ -39,6 +39,7 @@ struct acpi_dmar_header;
/* DMAR Flags */
#define DMAR_INTR_REMAP 0x1
#define DMAR_X2APIC_OPT_OUT 0x2
+#define DMAR_PLATFORM_OPT_IN 0x4
struct intel_iommu;
@@ -170,6 +171,8 @@ static inline int dmar_ir_hotplug(struct dmar_drhd_unit *dmaru, bool insert)
{ return 0; }
#endif /* CONFIG_IRQ_REMAP */
+extern bool dmar_platform_optin(void);
+
#else /* CONFIG_DMAR_TABLE */
static inline int dmar_device_add(void *handle)
@@ -182,6 +185,11 @@ static inline int dmar_device_remove(void *handle)
return 0;
}
+static inline bool dmar_platform_optin(void)
+{
+ return false;
+}
+
#endif /* CONFIG_DMAR_TABLE */
struct irte {