Merge tag 'x86_mm_for_6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 LAM (Linear Address Masking) support from Dave Hansen:
 "Add support for the new Linear Address Masking CPU feature.

  This is similar to ARM's Top Byte Ignore and allows userspace to store
  metadata in some bits of pointers without masking it out before use"

* tag 'x86_mm_for_6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/iommu/sva: Do not allow to set FORCE_TAGGED_SVA bit from outside
  x86/mm/iommu/sva: Fix error code for LAM enabling failure due to SVA
  selftests/x86/lam: Add test cases for LAM vs thread creation
  selftests/x86/lam: Add ARCH_FORCE_TAGGED_SVA test cases for linear-address masking
  selftests/x86/lam: Add inherit test cases for linear-address masking
  selftests/x86/lam: Add io_uring test cases for linear-address masking
  selftests/x86/lam: Add mmap and SYSCALL test cases for linear-address masking
  selftests/x86/lam: Add malloc and tag-bits test cases for linear-address masking
  x86/mm/iommu/sva: Make LAM and SVA mutually exclusive
  iommu/sva: Replace pasid_valid() helper with mm_valid_pasid()
  mm: Expose untagging mask in /proc/$PID/status
  x86/mm: Provide arch_prctl() interface for LAM
  x86/mm: Reduce untagged_addr() overhead for systems without LAM
  x86/uaccess: Provide untagged_addr() and remove tags before address check
  mm: Introduce untagged_addr_remote()
  x86/mm: Handle LAM on context switch
  x86: CPUID and CR3/CR4 flags for Linear Address Masking
  x86: Allow atomic MM_CONTEXT flags setting
  x86/mm: Rework address range check in get_user() and put_user()

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
index 24bf9b2b58aa..dd76a1a09cf7 100644
--- a/drivers/iommu/iommu-sva.c
+++ b/drivers/iommu/iommu-sva.c
@@ -2,6 +2,7 @@
 /*
  * Helpers for IOMMU drivers implementing SVA
  */
+#include <linux/mmu_context.h>
 #include <linux/mutex.h>
 #include <linux/sched/mm.h>
 #include <linux/iommu.h>
@@ -32,16 +33,19 @@ int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max)
 	    min == 0 || max < min)
 		return -EINVAL;
 
+	if (!arch_pgtable_dma_compat(mm))
+		return -EBUSY;
+
 	mutex_lock(&iommu_sva_lock);
 	/* Is a PASID already associated with this mm? */
-	if (pasid_valid(mm->pasid)) {
+	if (mm_valid_pasid(mm)) {
 		if (mm->pasid < min || mm->pasid >= max)
 			ret = -EOVERFLOW;
 		goto out;
 	}
 
 	pasid = ioasid_alloc(&iommu_sva_pasid, min, max, mm);
-	if (!pasid_valid(pasid))
+	if (pasid == INVALID_IOASID)
 		ret = -ENOMEM;
 	else
 		mm_pasid_set(mm, pasid);