[Xen-devel] [PATCH] x86/vtd: fix IOMMU share PT destruction path

[Wei Liu <wei.liu2@xxxxxxxxxx>]

Commit 2916951c1 ("mm / iommu: include need_iommu() test in
iommu_use_hap_pt()") included need_iommu() in iommu_use_hap_pt and
91d4eca7add (" mm / iommu: split need_iommu() into has_iommu_pt() and
need_iommu_pt_sync()") made things finer grain by spliting need_iommu
into three states.

The destruction path can't use iommu_use_hap_pt because at the point
platform op is called, IOMMU is already switched to disabled state and
the shared PT test would always be false.

Signed-off-by: Wei Liu <wei.liu2@xxxxxxxxxx>
---
 xen/drivers/passthrough/vtd/iommu.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/xen/drivers/passthrough/vtd/iommu.c 
b/xen/drivers/passthrough/vtd/iommu.c
index f94b522c73..d66d9e8ad0 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1752,7 +1752,13 @@ static void iommu_domain_teardown(struct domain *d)
         xfree(mrmrr);
     }
 
-    if ( iommu_use_hap_pt(d) )
+    ASSERT(hap_enabled(d));
+
+    /*
+     * We can't use iommu_use_hap_pt here because the IOMMU state is already
+     * changed to IOMMU_STATUS_disabled at this point.
+     */
+    if ( iommu_hap_pt_share )
         return;
 
     spin_lock(&hd->arch.mapping_lock);
-- 
2.11.0


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel