Commit 91bc81b9 authored by Jacob Pan's avatar Jacob Pan Committed by Greg Kroah-Hartman

iommu/vt-d: Fix pasid table size encoding

commit 65ca7f5f upstream.

Different encodings are used to represent supported PASID bits
and number of PASID table entries.
The current code assigns ecap_pss directly to extended context
table entry PTS which is wrong and could result in writing
non-zero bits to the reserved fields. IOMMU fault reason
11 will be reported when reserved bits are nonzero.
This patch converts ecap_pss to extend context entry pts encoding
based on VT-d spec. Chapter 9.4 as follows:
 - number of PASID bits = ecap_pss + 1
 - number of PASID table entries = 2^(pts + 5)
Software assigned limit of pasid_max value is also respected to
match the allocation limitation of PASID table.

cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: default avatarJacob Pan <jacob.jun.pan@linux.intel.com>
Tested-by: default avatarMika Kuoppala <mika.kuoppala@intel.com>
Fixes: 2f26e0a9 ('iommu/vt-d: Add basic SVM PASID support')
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent dc78a9e1
......@@ -5020,6 +5020,25 @@ static void intel_iommu_remove_device(struct device *dev)
}
#ifdef CONFIG_INTEL_IOMMU_SVM
#define MAX_NR_PASID_BITS (20)
static inline unsigned long intel_iommu_get_pts(struct intel_iommu *iommu)
{
/*
* Convert ecap_pss to extend context entry pts encoding, also
* respect the soft pasid_max value set by the iommu.
* - number of PASID bits = ecap_pss + 1
* - number of PASID table entries = 2^(pts + 5)
* Therefore, pts = ecap_pss - 4
* e.g. KBL ecap_pss = 0x13, PASID has 20 bits, pts = 15
*/
if (ecap_pss(iommu->ecap) < 5)
return 0;
/* pasid_max is encoded as actual number of entries not the bits */
return find_first_bit((unsigned long *)&iommu->pasid_max,
MAX_NR_PASID_BITS) - 5;
}
int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sdev)
{
struct device_domain_info *info;
......@@ -5052,7 +5071,9 @@ int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sd
if (!(ctx_lo & CONTEXT_PASIDE)) {
context[1].hi = (u64)virt_to_phys(iommu->pasid_state_table);
context[1].lo = (u64)virt_to_phys(iommu->pasid_table) | ecap_pss(iommu->ecap);
context[1].lo = (u64)virt_to_phys(iommu->pasid_table) |
intel_iommu_get_pts(iommu);
wmb();
/* CONTEXT_TT_MULTI_LEVEL and CONTEXT_TT_DEV_IOTLB are both
* extended to permit requests-with-PASID if the PASIDE bit
......
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