From 4df4eab168c1c4058603be55a3169d4a45779cc0 Mon Sep 17 00:00:00 2001
From: Joerg Roedel <jroedel@suse.de>
Date: Tue, 25 Aug 2015 10:54:28 +0200
Subject: [PATCH] iommu/vt-d: Really use upper context table when necessary
There is a bug in iommu_context_addr() which will always use
the lower context table, even when the upper context table
needs to be used. Fix this issue.
Fixes: 03ecc32c5274 ("iommu/vt-d: support extended root and context entries")
Reported-by: Xiao, Nan <nan.xiao@hp.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/intel-iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index a85077d4335b5..63daf1ba04b7e 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -803,6 +803,7 @@ static inline struct context_entry *iommu_context_addr(struct intel_iommu *iommu
struct context_entry *context;
u64 *entry;
+ entry = &root->lo;
if (ecs_enabled(iommu)) {
if (devfn >= 0x80) {
devfn -= 0x80;
@@ -810,7 +811,6 @@ static inline struct context_entry *iommu_context_addr(struct intel_iommu *iommu
}
devfn *= 2;
}
- entry = &root->lo;
if (*entry & 1)
context = phys_to_virt(*entry & VTD_PAGE_MASK);
else {