Merge tag 'iommu-fixes-v4.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu fixes from Joerg Roedel:
"Two late fixes for the AMD IOMMU driver:
- add an additional check to the io page-fault handler to avoid a
BUG_ON being hit in handle_mm_fault()
- fix a problem with devices writing to the system management area
and were blocked by the IOMMU because the driver wrongly cleared
out the DTE flags allowing that access"
* tag 'iommu-fixes-v4.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Don't clear DTE flags when modifying it
iommu/amd: Fix BUG when faulting a PROT_NONE VMA
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 08d2775..532e2a2 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1974,8 +1974,8 @@
static void clear_dte_entry(u16 devid)
{
/* remove entry from the device table seen by the hardware */
- amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;
- amd_iommu_dev_table[devid].data[1] = 0;
+ amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;
+ amd_iommu_dev_table[devid].data[1] &= DTE_FLAG_MASK;
amd_iommu_apply_erratum_63(devid);
}
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index f659088..c9b6472 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -295,6 +295,7 @@
#define IOMMU_PTE_IR (1ULL << 61)
#define IOMMU_PTE_IW (1ULL << 62)
+#define DTE_FLAG_MASK (0x3ffULL << 32)
#define DTE_FLAG_IOTLB (0x01UL << 32)
#define DTE_FLAG_GV (0x01ULL << 55)
#define DTE_GLX_SHIFT (56)
diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index 1131664..d21d4ed 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -516,6 +516,13 @@
goto out;
}
+ if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))) {
+ /* handle_mm_fault would BUG_ON() */
+ up_read(&mm->mmap_sem);
+ handle_fault_error(fault);
+ goto out;
+ }
+
ret = handle_mm_fault(mm, vma, address, write);
if (ret & VM_FAULT_ERROR) {
/* failed to service fault */