[ 3.5.y.z extended stable ] Patch "iommu/amd: Initialize device table after dma_ops" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    iommu/amd: Initialize device table after dma_ops

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 97f6ea84526b1a7324d4c11f58988ddf4f7ad134 Mon Sep 17 00:00:00 2001
From: Joerg Roedel <joro at 8bytes.org>
Date: Wed, 6 Feb 2013 12:55:23 +0100
Subject: [PATCH] iommu/amd: Initialize device table after dma_ops

commit f528d980c17b8714aedc918ba86e058af914d66b upstream.

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.

Signed-off-by: Joerg Roedel <joro at 8bytes.org>
Signed-off-by: Shuah Khan <shuah.khan at hp.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/iommu/amd_iommu_init.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index eadc6b5..9e5096a 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1572,9 +1572,6 @@ int __init amd_iommu_init_hardware(void)
 	if (amd_iommu_pd_alloc_bitmap == NULL)
 		goto free;

-	/* init the device table */
-	init_device_table();
-
 	/*
 	 * let all alias entries point to itself
 	 */
@@ -1655,6 +1652,7 @@ out:
  */
 static int __init amd_iommu_init(void)
 {
+	struct amd_iommu *iommu;
 	int ret = 0;

 	ret = amd_iommu_init_hardware();
@@ -1673,6 +1671,12 @@ static int __init amd_iommu_init(void)
 	if (ret)
 		goto free;

+	/* init the device table */
+	init_device_table();
+
+	for_each_iommu(iommu)
+		iommu_flush_all_caches(iommu);
+
 	amd_iommu_init_api();

 	x86_platform.iommu_shutdown = disable_iommus;
--
1.8.1.2