From: Ankit Soni <Ankit.Soni@amd.com>
Date: Mon, 13 Apr 2026 14:45:19 +0000 (+0000)
Subject: iommu_pt: support small VA for AMDv1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5240dab55b51c5f14448643ad044a5643f5b569b;p=thirdparty%2Fkernel%2Flinux.git

iommu_pt: support small VA for AMDv1

When hardware/VM request a small VA limit, the generic page-table code
clears PT_FEAT_DYNAMIC_TOP. This later causes domain initialization to
fail with -EOPNOTSUPP.

Remove the clearing so init succeeds when the VA fits in the starting
level and no top-level growth is needed.

Signed-off-by: Ankit Soni <Ankit.Soni@amd.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---

diff --git a/drivers/iommu/generic_pt/iommu_pt.h b/drivers/iommu/generic_pt/iommu_pt.h
index 1765986e24e82..512c03f72d921 100644
--- a/drivers/iommu/generic_pt/iommu_pt.h
+++ b/drivers/iommu/generic_pt/iommu_pt.h
@@ -1149,10 +1149,6 @@ static int pt_init_common(struct pt_common *common)
 	if (PT_WARN_ON(top_range.top_level > PT_MAX_TOP_LEVEL))
 		return -EINVAL;
 
-	if (top_range.top_level == PT_MAX_TOP_LEVEL ||
-	    common->max_vasz_lg2 == top_range.max_vasz_lg2)
-		common->features &= ~BIT(PT_FEAT_DYNAMIC_TOP);
-
 	if (top_range.max_vasz_lg2 == PT_VADDR_MAX_LG2)
 		common->features |= BIT(PT_FEAT_FULL_VA);