Merge tag 'v4.13-rc1' into fixes

The fixes branch is based off a random pre-rc1 commit, because we had
some fixes that needed to go in before rc1 was released.

However we now need to fix some code that went in after that point, but
before rc1, so merge rc1 to get that code into fixes so we can fix it!

1 files changed, 35 insertions, 9 deletions

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 5a11328f4d98..5cc597b383c7 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -29,6 +29,7 @@
 #include <linux/export.h>
 #include <linux/iommu.h>
 #include <linux/kmemleak.h>
+#include <linux/crash_dump.h>
 #include <asm/pci-direct.h>
 #include <asm/iommu.h>
 #include <asm/gart.h>
@@ -236,6 +237,7 @@ enum iommu_init_state {
 	IOMMU_INITIALIZED,
 	IOMMU_NOT_FOUND,
 	IOMMU_INIT_ERROR,
+	IOMMU_CMDLINE_DISABLED,
 };
 
 /* Early ioapic and hpet maps from kernel command line */
@@ -588,6 +590,8 @@ void amd_iommu_reset_cmd_buffer(struct amd_iommu *iommu)
 
 	writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
 	writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
+	iommu->cmd_buf_head = 0;
+	iommu->cmd_buf_tail = 0;
 
 	iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
 }
@@ -1898,6 +1902,14 @@ static void init_device_table_dma(void)
 	for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) {
 		set_dev_entry_bit(devid, DEV_ENTRY_VALID);
 		set_dev_entry_bit(devid, DEV_ENTRY_TRANSLATION);
+		/*
+		 * In kdump kernels in-flight DMA from the old kernel might
+		 * cause IO_PAGE_FAULTs. There are no reports that a kdump
+		 * actually failed because of that, so just disable fault
+		 * reporting in the hardware to get rid of the messages
+		 */
+		if (is_kdump_kernel())
+			set_dev_entry_bit(devid, DEV_ENTRY_NO_PAGE_FAULT);
 	}
 }
 
@@ -2097,23 +2109,27 @@ static struct syscore_ops amd_iommu_syscore_ops = {
 	.resume = amd_iommu_resume,
 };
 
-static void __init free_on_init_error(void)
+static void __init free_iommu_resources(void)
 {
 	kmemleak_free(irq_lookup_table);
 	free_pages((unsigned long)irq_lookup_table,
 		   get_order(rlookup_table_size));
+	irq_lookup_table = NULL;
 
 	kmem_cache_destroy(amd_iommu_irq_cache);
 	amd_iommu_irq_cache = NULL;
 
 	free_pages((unsigned long)amd_iommu_rlookup_table,
 		   get_order(rlookup_table_size));
+	amd_iommu_rlookup_table = NULL;
 
 	free_pages((unsigned long)amd_iommu_alias_table,
 		   get_order(alias_table_size));
+	amd_iommu_alias_table = NULL;
 
 	free_pages((unsigned long)amd_iommu_dev_table,
 		   get_order(dev_table_size));
+	amd_iommu_dev_table = NULL;
 
 	free_iommu_all();
 
@@ -2183,6 +2199,7 @@ static void __init free_dma_resources(void)
 {
 	free_pages((unsigned long)amd_iommu_pd_alloc_bitmap,
 		   get_order(MAX_DOMAIN_ID/8));
+	amd_iommu_pd_alloc_bitmap = NULL;
 
 	free_unity_maps();
 }
@@ -2307,6 +2324,9 @@ static int __init early_amd_iommu_init(void)
 	if (ret)
 		goto out;
 
+	/* Disable any previously enabled IOMMUs */
+	disable_iommus();
+
 	if (amd_iommu_irq_remap)
 		amd_iommu_irq_remap = check_ioapic_information();
 
@@ -2410,6 +2430,13 @@ static int __init state_next(void)
 	case IOMMU_IVRS_DETECTED:
 		ret = early_amd_iommu_init();
 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
+		if (init_state == IOMMU_ACPI_FINISHED && amd_iommu_disabled) {
+			pr_info("AMD-Vi: AMD IOMMU disabled on kernel command-line\n");
+			free_dma_resources();
+			free_iommu_resources();
+			init_state = IOMMU_CMDLINE_DISABLED;
+			ret = -EINVAL;
+		}
 		break;
 	case IOMMU_ACPI_FINISHED:
 		early_enable_iommus();
@@ -2438,6 +2465,7 @@ static int __init state_next(void)
 		break;
 	case IOMMU_NOT_FOUND:
 	case IOMMU_INIT_ERROR:
+	case IOMMU_CMDLINE_DISABLED:
 		/* Error states => do nothing */
 		ret = -EINVAL;
 		break;
@@ -2451,13 +2479,14 @@ static int __init state_next(void)
 
 static int __init iommu_go_to_state(enum iommu_init_state state)
 {
-	int ret = 0;
+	int ret = -EINVAL;
 
 	while (init_state != state) {
-		ret = state_next();
-		if (init_state == IOMMU_NOT_FOUND ||
-		    init_state == IOMMU_INIT_ERROR)
+		if (init_state == IOMMU_NOT_FOUND         ||
+		    init_state == IOMMU_INIT_ERROR        ||
+		    init_state == IOMMU_CMDLINE_DISABLED)
 			break;
+		ret = state_next();
 	}
 
 	return ret;
@@ -2522,7 +2551,7 @@ static int __init amd_iommu_init(void)
 		free_dma_resources();
 		if (!irq_remapping_enabled) {
 			disable_iommus();
-			free_on_init_error();
+			free_iommu_resources();
 		} else {
 			struct amd_iommu *iommu;
 
@@ -2549,9 +2578,6 @@ int __init amd_iommu_detect(void)
 	if (no_iommu || (iommu_detected && !gart_iommu_aperture))
 		return -ENODEV;
 
-	if (amd_iommu_disabled)
-		return -ENODEV;
-
 	ret = iommu_go_to_state(IOMMU_IVRS_DETECTED);
 	if (ret)
 		return ret;