[PATCH 2/2] iommu/vt-d: tylersburg isoch identity map check is done too late.

From: Ashok Raj
Date: Thu Jan 26 2017 - 16:53:33 EST


The check to set identity map for tylersburg is done too late. It needs
to be done before the check for identity_map domain is done.

To: Joerg Roedel <joro@xxxxxxxxxx>
To: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Cc: Ashok Raj <ashok.raj@xxxxxxxxx>

Signed-off-by: Ashok Raj <ashok.raj@xxxxxxxxx>
Reported-by: Yunhong Jiang <yunhong.jiang@xxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 8a18525..23eead3 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3325,13 +3325,14 @@ static int __init init_dmars(void)
iommu_identity_mapping |= IDENTMAP_GFX;
#endif

+ check_tylersburg_isoch();
+
if (iommu_identity_mapping) {
ret = si_domain_init(hw_pass_through);
if (ret)
goto free_iommu;
}

- check_tylersburg_isoch();

/*
* If we copied translations from a previous kernel in the kdump
--
2.7.4