blob: d3185ef6fa581d8fdc71bcdbcdb6184774094876 [file] [log] [blame]
From fc61c02abaabe9c9bb88b9be58db9f6d2b2128c0 Mon Sep 17 00:00:00 2001
From: Jacob Pan <jacob.jun.pan@linux.intel.com>
Date: Thu, 2 Jan 2020 08:18:07 +0800
Subject: [PATCH] iommu/vt-d: Fix off-by-one in PASID allocation
commit 39d630e332144028f56abba83d94291978e72df1 upstream.
PASID allocator uses IDR which is exclusive for the end of the
allocation range. There is no need to decrement pasid_max.
Fixes: af39507305fb ("iommu/vt-d: Apply global PASID in SVA")
Reported-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 12afcc0048f7..1212cd01533f 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -317,7 +317,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_
/* Do not use PASID 0 in caching mode (virtualised IOMMU) */
ret = intel_pasid_alloc_id(svm,
!!cap_caching_mode(iommu->cap),
- pasid_max - 1, GFP_KERNEL);
+ pasid_max, GFP_KERNEL);
if (ret < 0) {
kfree(svm);
kfree(sdev);
--
2.7.4