Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - make the debugfs 'kernel_page_tables' file read-only, as it only
     has read ops.  (Borislav Petkov)

   - micro-optimize clflush_cache_range() (Chris Wilson)

   - swiotlb enhancements, which fixes certain KVM emulated devices
     (Igor Mammedov)

   - fix an LDT related debug message (Jan Beulich)

   - modularize CONFIG_X86_PTDUMP (Kees Cook)

   - tone down an overly alarming warning (Laura Abbott)

   - Mark variable __initdata (Rasmus Villemoes)

   - PAT additions (Toshi Kani)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Micro-optimise clflush_cache_range()
  x86/mm/pat: Change free_memtype() to support shrinking case
  x86/mm/pat: Add untrack_pfn_moved for mremap
  x86/mm: Drop WARN from multi-BAR check
  x86/LDT: Print the real LDT base address
  x86/mm/64: Enable SWIOTLB if system has SRAT memory regions above MAX_DMA32_PFN
  x86/mm: Introduce max_possible_pfn
  x86/mm/ptdump: Make (debugfs)/kernel_page_tables read-only
  x86/mm/mtrr: Mark the 'range_new' static variable in mtrr_calc_range_state() as __initdata
  x86/mm: Turn CONFIG_X86_PTDUMP into a module

1 files changed, 11 insertions, 1 deletions

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 188e3e07eeeb..031782e74231 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -586,7 +586,7 @@ int free_memtype(u64 start, u64 end)
 	entry = rbt_memtype_erase(start, end);
 	spin_unlock(&memtype_lock);
 
-	if (!entry) {
+	if (IS_ERR(entry)) {
 		pr_info("x86/PAT: %s:%d freeing invalid memtype [mem %#010Lx-%#010Lx]\n",
 			current->comm, current->pid, start, end - 1);
 		return -EINVAL;
@@ -992,6 +992,16 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
 	vma->vm_flags &= ~VM_PAT;
 }
 
+/*
+ * untrack_pfn_moved is called, while mremapping a pfnmap for a new region,
+ * with the old vma after its pfnmap page table has been removed.  The new
+ * vma has a new pfnmap to the same pfn & cache type with VM_PAT set.
+ */
+void untrack_pfn_moved(struct vm_area_struct *vma)
+{
+	vma->vm_flags &= ~VM_PAT;
+}
+
 pgprot_t pgprot_writecombine(pgprot_t prot)
 {
 	return __pgprot(pgprot_val(prot) |