Re: [PATCH] mm: Track page table modifications in __apply_to_page_range() construction

21 Aug 2020


      Quoting Joerg Roedel (2020-08-21 11:09:02)
...
@@ -2333,6 +2339,7 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
        pgd_t *pgd;
        unsigned long next;
        unsigned long end = addr + size;

  pgtbl_mod_mask mask = 0;
  int err = 0;



if (WARN_ON(addr >= end))
@@ -2343,11 +2350,14 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
                next = pgd_addr_end(addr, end);
                if (!create && pgd_none_or_clear_bad(pgd))
                        continue;

          err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create);




          err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create, &mask);
          if (err)
                  break;
  } while (pgd++, addr = next, addr != end);




  if (mask & ARCH_PAGE_TABLE_SYNC_MASK)


          arch_sync_kernel_mappings(addr, addr + size);



We need to store the initial addr, as here addr == end [or earlier on
earlier], so range is (start, addr).
-Chris

    