Merge tag 'iommu-updates-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:

 - SMMU Updates from Will Deacon:

     - SMMUv3:
        - Support stalling faults for platform devices
        - Decrease defaults sizes for the event and PRI queues
     - SMMUv2:
        - Support for a new '->probe_finalize' hook, needed by Nvidia
        - Even more Qualcomm compatible strings
        - Avoid Adreno TTBR1 quirk for DB820C platform

 - Intel VT-d updates from Lu Baolu:

     - Convert Intel IOMMU to use sva_lib helpers in iommu core
     - ftrace and debugfs supports for page fault handling
     - Support asynchronous nested capabilities
     - Various misc cleanups

 - Support for new VIOT ACPI table to make the VirtIO IOMMU
   available on x86

 - Add the amd_iommu=force_enable command line option to enable
   the IOMMU on platforms where they are known to cause problems

 - Support for version 2 of the Rockchip IOMMU

 - Various smaller fixes, cleanups and refactorings

* tag 'iommu-updates-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (66 commits)
  iommu/virtio: Enable x86 support
  iommu/dma: Pass address limit rather than size to iommu_setup_dma_ops()
  ACPI: Add driver for the VIOT table
  ACPI: Move IOMMU setup code out of IORT
  ACPI: arm64: Move DMA setup operations out of IORT
  iommu/vt-d: Fix dereference of pointer info before it is null checked
  iommu: Update "iommu.strict" documentation
  iommu/arm-smmu: Check smmu->impl pointer before dereferencing
  iommu/arm-smmu-v3: Remove unnecessary oom message
  iommu/arm-smmu: Fix arm_smmu_device refcount leak in address translation
  iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails
  iommu/vt-d: Fix linker error on 32-bit
  iommu/vt-d: No need to typecast
  iommu/vt-d: Define counter explicitly as unsigned int
  iommu/vt-d: Remove unnecessary braces
  iommu/vt-d: Removed unused iommu_count in dmar domain
  iommu/vt-d: Use bitfields for DMAR capabilities
  iommu/vt-d: Use DEVICE_ATTR_RO macro
  iommu/vt-d: Fix out-bounds-warning in intel/svm.c
  iommu/vt-d: Add PRQ handling latency sampling
  ...

1 files changed, 8 insertions, 1 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 13f13fdd4731..0081d83457e8 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -301,6 +301,9 @@
 					  allowed anymore to lift isolation
 					  requirements as needed. This option
 					  does not override iommu=pt
+			force_enable - Force enable the IOMMU on platforms known
+				       to be buggy with IOMMU enabled. Use this
+				       option with care.
 
 	amd_iommu_dump=	[HW,X86-64]
 			Enable AMD IOMMU driver option to dump the ACPI table
@@ -2031,7 +2034,7 @@
 			  forcing Dual Address Cycle for PCI cards supporting
 			  greater than 32-bit addressing.
 
-	iommu.strict=	[ARM64] Configure TLB invalidation behaviour
+	iommu.strict=	[ARM64, X86] Configure TLB invalidation behaviour
 			Format: { "0" | "1" }
 			0 - Lazy mode.
 			  Request that DMA unmap operations use deferred
@@ -2042,6 +2045,10 @@
 			1 - Strict mode (default).
 			  DMA unmap operations invalidate IOMMU hardware TLBs
 			  synchronously.
+			Note: on x86, the default behaviour depends on the
+			equivalent driver-specific parameters, but a strict
+			mode explicitly specified by either method takes
+			precedence.
 
 	iommu.passthrough=
 			[ARM64, X86] Configure DMA to bypass the IOMMU by default.