iommu/amd: Reserve exclusion range in iova-domain

BugLink: https://bugs.launchpad.net/bugs/1823037
If a device has an exclusion range specified in the IVRS
table, this region needs to be reserved in the iova-domain
of that device. This hasn't happened until now and can cause
data corruption on data transfered with these devices.

Treat exclusion ranges as reserved regions in the iommu-core
to fix the problem.

Fixes: be2a022c0dd0 ('x86, AMD IOMMU: add functions to parse IOMMU memory mapping requirements for devices')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Gary R Hook <gary.hook@amd.com>
(cherry picked from commit 8aafaaf2212192012f5bae305bb31cdf7681d777 )
Signed-off-by: Jeffrey Lane <jeffrey.lane@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 3e7efe466856246112ed55e35cd09d7957a08e95..8ddc2f1c56566175533d6639a75e8677ce03d3d7 100644 (file)
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3102,21 +3102,24 @@ static void amd_iommu_get_resv_regions(struct device *dev,
                return;
 
        list_for_each_entry(entry, &amd_iommu_unity_map, list) {
+               int type, prot = 0;
                size_t length;
-               int prot = 0;
 
                if (devid < entry->devid_start || devid > entry->devid_end)
                        continue;
 
+               type   = IOMMU_RESV_DIRECT;
                length = entry->address_end - entry->address_start;
                if (entry->prot & IOMMU_PROT_IR)
                        prot |= IOMMU_READ;
                if (entry->prot & IOMMU_PROT_IW)
                        prot |= IOMMU_WRITE;
+               if (entry->prot & IOMMU_UNITY_MAP_FLAG_EXCL_RANGE)
+                       /* Exclusion range */
+                       type = IOMMU_RESV_RESERVED;
 
                region = iommu_alloc_resv_region(entry->address_start,
-                                                length, prot,
-                                                IOMMU_RESV_DIRECT);
+                                                length, prot, type);
                if (!region) {
                        pr_err("Out of memory allocating dm-regions for %s\n",
                                dev_name(dev));

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 1652c7ecb3390c57614117dbd564baaa80d4e470..c304ca07047c13e91aa2086783bba3bdac5a002e 100644 (file)
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1999,6 +1999,9 @@ static int __init init_unity_map_range(struct ivmd_header *m)
        if (e == NULL)
                return -ENOMEM;
 
+       if (m->flags & IVMD_FLAG_EXCL_RANGE)
+               init_exclusion_range(m);
+
        switch (m->type) {
        default:
                kfree(e);
@@ -2045,9 +2048,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
 
        while (p < end) {
                m = (struct ivmd_header *)p;
-               if (m->flags & IVMD_FLAG_EXCL_RANGE)
-                       init_exclusion_range(m);
-               else if (m->flags & IVMD_FLAG_UNITY_MAP)
+               if (m->flags & (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))
                        init_unity_map_range(m);
 
                p += m->length;

diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index dd11091cfdb3359f3e9d8be83912b397aca5ec4d..0b73d0508a3d699467fb9c4d43602291d6b76165 100644 (file)
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -370,6 +370,8 @@
 #define IOMMU_PROT_IR 0x01
 #define IOMMU_PROT_IW 0x02
 
+#define IOMMU_UNITY_MAP_FLAG_EXCL_RANGE        (1 << 2)
+
 /* IOMMU capabilities */
 #define IOMMU_CAP_IOTLB   24
 #define IOMMU_CAP_NPCACHE 26