[PATCH 2/4] iommu/vt-d: Report out when IOMMU features have inconsistencies

From: Kyung Min Park
Date: Tue Sep 22 2020 - 17:25:52 EST

Next message: Andrew Lunn: "Re: [RFC][Patch v1 1/3] sched/isolation: API to get num of hosekeeping CPUs"
Previous message: kernel test robot: "[tip:x86/fpu] BUILD SUCCESS 1ef5423a55c2ac6f1361811efe75b6e46d1023ed"
In reply to: Kyung Min Park: "[PATCH 0/4] Audit Capability and Extended Capability among IOMMUs"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

IOMMU features as below can have incompatibilities among IOMMUs.
Audit IOMMU Capability/Extended Capability and check if the IOMMUs have
the consistent value for features as below. Report out when features as
below have incompatibility among IOMMUs.

Report out features when below features are mismatched:
- First Level 5 Level Paging Support (FL5LP)
- First Level 1 GByte Page Support (FL1GP)
- Read Draining (DRD)
- Write Draining (DWD)
- Page Selective Invalidation (PSI)
- Caching Mode (CM)
- Protected High/Low-Memory Region (PHMR/PLMR)
- Scalable Mode Page Walk Coherency (SMPWC)
- First Level Translation Support (FLTS)
- Second Level Translation Support (SLTS)
- Second Level Accessed/Dirty Support (SLADS)
- Virtual Command Support (VCS)
- Scalable Mode Translation Support (SMTS)
- Device TLB Invalidation Throttle (DIT)
- Page Drain Support (PDS)
- Nested Translation Support (NEST)
- Snoop Control (SC)
- Pass Through (PT)
- Device TLB Support (DT)
- Queued Invalidation (QI)
- Page walk Coherency (C)

Signed-off-by: Kyung Min Park <kyung.min.park@xxxxxxxxx>
---
drivers/iommu/intel/audit.c | 48 +++++++++++++++++++++++++++++++++++++
drivers/iommu/intel/audit.h | 43 +++++++++++++++++++++++++++++++++
include/linux/intel-iommu.h | 2 ++
3 files changed, 93 insertions(+)

diff --git a/drivers/iommu/intel/audit.c b/drivers/iommu/intel/audit.c
index 2893170f5b6c..f783acabb402 100644
--- a/drivers/iommu/intel/audit.c
+++ b/drivers/iommu/intel/audit.c
@@ -13,6 +13,8 @@
#include "audit.h"

static bool svm_sanity_check = true;
+/* global variables that hold feature consistency and minimum features */
+static u64 intel_iommu_cap_sanity = ~0ULL;
static u64 intel_iommu_ecap_sanity = ~0ULL;

static void set_cap_audit_svm_sanity(bool svm_sanity)
@@ -30,12 +32,58 @@ static inline void check_dmar_capabilities(struct intel_iommu *a,
{
if (MINIMAL_SVM_ECAP & (a->ecap ^ b->ecap))
set_cap_audit_svm_sanity(false);
+
+ CHECK_FEATURE_MISMATCH(a, b, cap, 5lp_support, CAP_FL5LP_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, fl1gp_support, CAP_FL1GP_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, read_drain, CAP_RD_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, write_drain, CAP_WD_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, pgsel_inv, CAP_PSI_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, caching_mode, CAP_CM_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, phmr, CAP_PHMR_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, cap, plmr, CAP_PLMR_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, smpwc, ECAP_SMPWC_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, flts, ECAP_FLTS_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, slts, ECAP_SLTS_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, slads, ECAP_SLADS_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, vcs, ECAP_VCS_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, smts, ECAP_SMTS_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, pds, ECAP_PDS_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, dit, ECAP_DIT_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, nest, ECAP_NEST_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, sc_support, ECAP_SC_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, pass_through, ECAP_PT_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, dev_iotlb_support, ECAP_DT_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, qis, ECAP_QI_MASK);
+ CHECK_FEATURE_MISMATCH(a, b, ecap, coherent, ECAP_C_MASK);
}

static int audit_iommu_capabilities_hotplug(struct intel_iommu *hot_iommu)
{
bool mismatch = false;

+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, 5lp_support, CAP_FL5LP_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, fl1gp_support, CAP_FL1GP_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, read_drain, CAP_RD_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, write_drain, CAP_WD_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, pgsel_inv, CAP_PSI_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, caching_mode, CAP_CM_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, phmr, CAP_PHMR_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, cap, plmr, CAP_PLMR_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, smpwc, ECAP_SMPWC_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, flts, ECAP_FLTS_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, slts, ECAP_SLTS_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, slads, ECAP_SLADS_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, vcs, ECAP_VCS_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, smts, ECAP_SMTS_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, pds, ECAP_PDS_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, dit, ECAP_DIT_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, nest, ECAP_NEST_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, sc_support, ECAP_SC_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, pass_through, ECAP_PT_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, dev_iotlb_support, ECAP_DT_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, qis, ECAP_QI_MASK);
+ CHECK_FEATURE_MISMATCH_HOTPLUG(hot_iommu, ecap, coherent, ECAP_C_MASK);
+
if (!IS_ENABLED(CONFIG_INTEL_IOMMU_SVM))
goto out;

diff --git a/drivers/iommu/intel/audit.h b/drivers/iommu/intel/audit.h
index 887900d9517d..e3a370405f82 100644
--- a/drivers/iommu/intel/audit.h
+++ b/drivers/iommu/intel/audit.h
@@ -7,19 +7,62 @@
* Author: Kyung Min Park <kyung.min.park@xxxxxxxxx>
*/

+/*
+ * Capability Register Mask
+ */
+#define CAP_FL5LP_MASK BIT(60)
+#define CAP_FL1GP_MASK BIT(56)
+#define CAP_RD_MASK BIT(55)
+#define CAP_WD_MASK BIT(54)
+#define CAP_PSI_MASK BIT(39)
+#define CAP_CM_MASK BIT(7)
+#define CAP_PHMR_MASK BIT(6)
+#define CAP_PLMR_MASK BIT(5)
+
/*
* Extended Capability Register Mask
*/
+#define ECAP_SMPWC_MASK BIT(48)
#define ECAP_FLTS_MASK BIT(47)
+#define ECAP_SLTS_MASK BIT(46)
+#define ECAP_SLADS_MASK BIT(45)
+#define ECAP_VCS_MASK BIT(44)
+#define ECAP_SMTS_MASK BIT(43)
+#define ECAP_PDS_MASK BIT(42)
+#define ECAP_DIT_MASK BIT(41)
#define ECAP_PASID_MASK BIT(40)
#define ECAP_EAFS_MASK BIT(34)
#define ECAP_SRS_MASK BIT(31)
#define ECAP_ERS_MASK BIT(30)
#define ECAP_PRS_MASK BIT(29)
+#define ECAP_NEST_MASK BIT(26)
+#define ECAP_SC_MASK BIT(7)
+#define ECAP_PT_MASK BIT(6)
+#define ECAP_DT_MASK BIT(2)
+#define ECAP_QI_MASK BIT(1)
+#define ECAP_C_MASK BIT(0)

#define MINIMAL_SVM_ECAP (ECAP_FLTS_MASK | ECAP_PASID_MASK | ECAP_EAFS_MASK | \
ECAP_SRS_MASK | ECAP_ERS_MASK | ECAP_PRS_MASK)

+#define DO_CHECK_FEATURE_MISMATCH(a, b, cap, feature, MASK) \
+do { \
+ if (cap##_##feature(a) != cap##_##feature(b)) { \
+ intel_iommu_##cap##_sanity &= ~(MASK); \
+ pr_info("IOMMU feature %s inconsistent.", #feature); \
+ } \
+} while (0)
+
+#define CHECK_FEATURE_MISMATCH(a, b, cap, feature, MASK) \
+ DO_CHECK_FEATURE_MISMATCH((a)->cap, (b)->cap, cap, feature, MASK)
+
+#define CHECK_FEATURE_MISMATCH_HOTPLUG(b, cap, feature, MASK) \
+do { \
+ if (cap##_##feature(intel_iommu_##cap##_sanity)) \
+ DO_CHECK_FEATURE_MISMATCH(intel_iommu_##cap##_sanity, \
+ (b)->cap, cap, feature, MASK); \
+} while (0)
+
enum cap_audit_type {
CAP_AUDIT_STATIC_DMAR,
CAP_AUDIT_HOTPLUG_DMAR,
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index b1ed2f25f7c0..6744f00a144a 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -171,8 +171,10 @@
#define ecap_smpwc(e) (((e) >> 48) & 0x1)
#define ecap_flts(e) (((e) >> 47) & 0x1)
#define ecap_slts(e) (((e) >> 46) & 0x1)
+#define ecap_slads(e) (((e) >> 45) & 0x1)
#define ecap_vcs(e) (((e) >> 44) & 0x1)
#define ecap_smts(e) (((e) >> 43) & 0x1)
+#define ecap_pds(e) (((e) >> 42) & 0x1)
#define ecap_dit(e) ((e >> 41) & 0x1)
#define ecap_pasid(e) ((e >> 40) & 0x1)
#define ecap_pss(e) ((e >> 35) & 0x1f)
--
2.17.1

Next message: Andrew Lunn: "Re: [RFC][Patch v1 1/3] sched/isolation: API to get num of hosekeeping CPUs"
Previous message: kernel test robot: "[tip:x86/fpu] BUILD SUCCESS 1ef5423a55c2ac6f1361811efe75b6e46d1023ed"
In reply to: Kyung Min Park: "[PATCH 0/4] Audit Capability and Extended Capability among IOMMUs"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]