Merge tag 'iommu-fixes-v4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

torvalds · torvalds · commit 19eab220e7a0 · 2016-03-03T11:32:13.000-08:00
Pull IOMMU fixes from Joerg Roedel:
 "One fix for Intel VT-d:

   - Use BUS_NOTIFY_REMOVED_DEVICE notifier to unbind a device from its
     domain _after_ it has been unbound from its driver.  This fixes a
     BUG_ON being triggered in the PCI hotplug path.

  And three for AMD IOMMU:

   - Add a workaround for a hardware issue with ATS in use

   - Fix ATS enable/disable balance when a device is removed

   - Fix a boot warning being triggered when the system has IOMMU
     performance counters and PCI device 00:00.0 is not covered by the
     IOMMU"

* tag 'iommu-fixes-v4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Use BUS_NOTIFY_REMOVED_DEVICE in hotplug path
  iommu/amd: Detach device from domain before removal
  iommu/amd: Apply workaround for ATS write permission check
  iommu/amd: Fix boot warning when device 00:00.0 is not iommu covered
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
@@ -114,6 +114,7 @@ struct kmem_cache *amd_iommu_irq_cache;
 
 static void update_domain(struct protection_domain *domain);
 static int protection_domain_init(struct protection_domain *domain);
+static void detach_device(struct device *dev);
 
 /*
  * For dynamic growth the aperture size is split into ranges of 128MB of
@@ -384,6 +385,9 @@ static void iommu_uninit_device(struct device *dev)
 	if (!dev_data)
 		return;
 
+	if (dev_data->domain)
+		detach_device(dev);
+
 	iommu_device_unlink(amd_iommu_rlookup_table[dev_data->devid]->iommu_dev,
 			    dev);
 
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
@@ -228,6 +228,10 @@ static int amd_iommu_enable_interrupts(void);
 static int __init iommu_go_to_state(enum iommu_init_state state);
 static void init_device_table_dma(void);
 
+static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
+				    u8 bank, u8 cntr, u8 fxn,
+				    u64 *value, bool is_write);
+
 static inline void update_last_devid(u16 devid)
 {
 	if (devid > amd_iommu_last_bdf)
@@ -1015,6 +1019,34 @@ static void amd_iommu_erratum_746_workaround(struct amd_iommu *iommu)
 	pci_write_config_dword(iommu->dev, 0xf0, 0x90);
 }
 
+/*
+ * Family15h Model 30h-3fh (IOMMU Mishandles ATS Write Permission)
+ * Workaround:
+ *     BIOS should enable ATS write permission check by setting
+ *     L2_DEBUG_3[AtsIgnoreIWDis](D0F2xF4_x47[0]) = 1b
+ */
+static void amd_iommu_ats_write_check_workaround(struct amd_iommu *iommu)
+{
+	u32 value;
+
+	if ((boot_cpu_data.x86 != 0x15) ||
+	    (boot_cpu_data.x86_model < 0x30) ||
+	    (boot_cpu_data.x86_model > 0x3f))
+		return;
+
+	/* Test L2_DEBUG_3[AtsIgnoreIWDis] == 1 */
+	value = iommu_read_l2(iommu, 0x47);
+
+	if (value & BIT(0))
+		return;
+
+	/* Set L2_DEBUG_3[AtsIgnoreIWDis] = 1 */
+	iommu_write_l2(iommu, 0x47, value | BIT(0));
+
+	pr_info("AMD-Vi: Applying ATS write check workaround for IOMMU at %s\n",
+		dev_name(&iommu->dev->dev));
+}
+
 /*
  * This function clues the initialization function for one IOMMU
  * together and also allocates the command buffer and programs the
@@ -1142,8 +1174,8 @@ static void init_iommu_perf_ctr(struct amd_iommu *iommu)
 	amd_iommu_pc_present = true;
 
 	/* Check if the performance counters can be written to */
-	if ((0 != amd_iommu_pc_get_set_reg_val(0, 0, 0, 0, &val, true)) ||
-	    (0 != amd_iommu_pc_get_set_reg_val(0, 0, 0, 0, &val2, false)) ||
+	if ((0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val, true)) ||
+	    (0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val2, false)) ||
 	    (val != val2)) {
 		pr_err("AMD-Vi: Unable to write to IOMMU perf counter.\n");
 		amd_iommu_pc_present = false;
@@ -1284,6 +1316,7 @@ static int iommu_init_pci(struct amd_iommu *iommu)
 	}
 
 	amd_iommu_erratum_746_workaround(iommu);
+	amd_iommu_ats_write_check_workaround(iommu);
 
 	iommu->iommu_dev = iommu_device_create(&iommu->dev->dev, iommu,
 					       amd_iommu_groups, "ivhd%d",
@@ -2283,22 +2316,15 @@ u8 amd_iommu_pc_get_max_counters(u16 devid)
 }
 EXPORT_SYMBOL(amd_iommu_pc_get_max_counters);
 
-int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
+				    u8 bank, u8 cntr, u8 fxn,
 				    u64 *value, bool is_write)
 {
-	struct amd_iommu *iommu;
 	u32 offset;
 	u32 max_offset_lim;
 
-	/* Make sure the IOMMU PC resource is available */
-	if (!amd_iommu_pc_present)
-		return -ENODEV;
-
-	/* Locate the iommu associated with the device ID */
-	iommu = amd_iommu_rlookup_table[devid];
-
 	/* Check for valid iommu and pc register indexing */
-	if (WARN_ON((iommu == NULL) || (fxn > 0x28) || (fxn & 7)))
+	if (WARN_ON((fxn > 0x28) || (fxn & 7)))
 		return -ENODEV;
 
 	offset = (u32)(((0x40|bank) << 12) | (cntr << 8) | fxn);
@@ -2322,3 +2348,16 @@ int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
 	return 0;
 }
 EXPORT_SYMBOL(amd_iommu_pc_get_set_reg_val);
+
+int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+				    u64 *value, bool is_write)
+{
+	struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
+
+	/* Make sure the IOMMU PC resource is available */
+	if (!amd_iommu_pc_present || iommu == NULL)
+		return -ENODEV;
+
+	return iommu_pc_get_set_reg_val(iommu, bank, cntr, fxn,
+					value, is_write);
+}
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
@@ -329,7 +329,8 @@ static int dmar_pci_bus_notifier(struct notifier_block *nb,
 	/* Only care about add/remove events for physical functions */
 	if (pdev->is_virtfn)
 		return NOTIFY_DONE;
-	if (action != BUS_NOTIFY_ADD_DEVICE && action != BUS_NOTIFY_DEL_DEVICE)
+	if (action != BUS_NOTIFY_ADD_DEVICE &&
+	    action != BUS_NOTIFY_REMOVED_DEVICE)
 		return NOTIFY_DONE;
 
 	info = dmar_alloc_pci_notify_info(pdev, action);
@@ -339,7 +340,7 @@ static int dmar_pci_bus_notifier(struct notifier_block *nb,
 	down_write(&dmar_global_lock);
 	if (action == BUS_NOTIFY_ADD_DEVICE)
 		dmar_pci_bus_add_dev(info);
-	else if (action == BUS_NOTIFY_DEL_DEVICE)
+	else if (action == BUS_NOTIFY_REMOVED_DEVICE)
 		dmar_pci_bus_del_dev(info);
 	up_write(&dmar_global_lock);
 
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
@@ -4367,7 +4367,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 				rmrru->devices_cnt);
 			if(ret < 0)
 				return ret;
-		} else if (info->event == BUS_NOTIFY_DEL_DEVICE) {
+		} else if (info->event == BUS_NOTIFY_REMOVED_DEVICE) {
 			dmar_remove_dev_scope(info, rmrr->segment,
 				rmrru->devices, rmrru->devices_cnt);
 		}
@@ -4387,7 +4387,7 @@ int dmar_iommu_notify_scope_dev(struct dmar_pci_notify_info *info)
 				break;
 			else if(ret < 0)
 				return ret;
-		} else if (info->event == BUS_NOTIFY_DEL_DEVICE) {
+		} else if (info->event == BUS_NOTIFY_REMOVED_DEVICE) {
 			if (dmar_remove_dev_scope(info, atsr->segment,
 					atsru->devices, atsru->devices_cnt))
 				break;
