When dma_ops are initialized the unity mappings are created. The
init_device_table_dma() function makes sure DMA from all devices is
blocked by default. This opens a short window in time where DMA to
unity mapped regions is blocked by the IOMMU. Make sure this does not
happen by initializing the device table after dma_ops.

Back-port upstream commit: f528d980c17b8714aedc918ba86e058af914d66b

Signed-off-by: Joerg Roedel <j...@8bytes.org>
Signed-off-by: Shuah Khan <shuah.k...@hp.com>
CC: sta...@vger.kernel.org 3.0
---
 arch/x86/kernel/amd_iommu_init.c |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 33df6e8..d86aa3f 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -1363,6 +1363,7 @@ static struct syscore_ops amd_iommu_syscore_ops = {
  */
 static int __init amd_iommu_init(void)
 {
+       struct amd_iommu *iommu;
        int i, ret = 0;
 
        /*
@@ -1411,9 +1412,6 @@ static int __init amd_iommu_init(void)
        if (amd_iommu_pd_alloc_bitmap == NULL)
                goto free;
 
-       /* init the device table */
-       init_device_table();
-
        /*
         * let all alias entries point to itself
         */
@@ -1463,6 +1461,12 @@ static int __init amd_iommu_init(void)
        if (ret)
                goto free_disable;
 
+       /* init the device table */
+       init_device_table();
+
+       for_each_iommu(iommu)
+               iommu_flush_all_caches(iommu);
+
        amd_iommu_init_api();
 
        amd_iommu_init_notifier();
-- 
1.7.9.5



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