Merge tag 'sunxi-fixes-for-5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git...

[linux-2.6-microblaze.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index c8e3576..550405f 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -166,7 +166,7 @@ static int __init init_zero_pfn(void)
        zero_pfn = page_to_pfn(ZERO_PAGE(0));
        return 0;
 }
-core_initcall(init_zero_pfn);
+early_initcall(init_zero_pfn);
 
 void mm_trace_rss_stat(struct mm_struct *mm, int member, long count)
 {
@@ -809,12 +809,8 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma
                  pte_t *dst_pte, pte_t *src_pte, unsigned long addr, int *rss,
                  struct page **prealloc, pte_t pte, struct page *page)
 {
-       struct mm_struct *src_mm = src_vma->vm_mm;
        struct page *new_page;
 
-       if (!is_cow_mapping(src_vma->vm_flags))
-               return 1;
-
        /*
         * What we want to do is to check whether this page may
         * have been pinned by the parent process.  If so,
@@ -828,9 +824,7 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma
         * the page count. That might give false positives for
         * for pinning, but it will work correctly.
         */
-       if (likely(!atomic_read(&src_mm->has_pinned)))
-               return 1;
-       if (likely(!page_maybe_dma_pinned(page)))
+       if (likely(!page_needs_cow_for_dma(src_vma, page)))
                return 1;
 
        new_page = *prealloc;
@@ -3103,6 +3097,14 @@ static vm_fault_t do_wp_page(struct vm_fault *vmf)
                return handle_userfault(vmf, VM_UFFD_WP);
        }
 
+       /*
+        * Userfaultfd write-protect can defer flushes. Ensure the TLB
+        * is flushed in this case before copying.
+        */
+       if (unlikely(userfaultfd_wp(vmf->vma) &&
+                    mm_tlb_flush_pending(vmf->vma->vm_mm)))
+               flush_tlb_page(vmf->vma, vmf->address);
+
        vmf->page = vm_normal_page(vma, vmf->address, vmf->orig_pte);
        if (!vmf->page) {
                /*