[PATCH 4.4 070/138] iommu/amd: Update Alias-DTE in update_device_table()

From: Greg Kroah-Hartman
Date: Thu Aug 18 2016 - 10:03:55 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Joerg Roedel <jroedel@xxxxxxx>

commit 3254de6bf74fe94c197c9f819fe62a3a3c36f073 upstream.

Not doing so might cause IO-Page-Faults when a device uses
an alias request-id and the alias-dte is left in a lower
page-mode which does not cover the address allocated from
the iova-allocator.

Fixes: 492667dacc0a ('x86/amd-iommu: Remove amd_iommu_pd_table')
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/iommu/amd_iommu.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2324,8 +2324,15 @@ static void update_device_table(struct p
{
struct iommu_dev_data *dev_data;

- list_for_each_entry(dev_data, &domain->dev_list, list)
+ list_for_each_entry(dev_data, &domain->dev_list, list) {
set_dte_entry(dev_data->devid, domain, dev_data->ats.enabled);
+
+ if (dev_data->devid == dev_data->alias)
+ continue;
+
+ /* There is an alias, update device table entry for it */
+ set_dte_entry(dev_data->alias, domain, dev_data->ats.enabled);
+ }
}

static void update_domain(struct protection_domain *domain)