MM: virtual address debug

Add some (configurable) expensive sanity checking to catch wrong address
translations on x86.

- create linux/mmdebug.h file to be able include this file in
  asm headers to not get unsolvable loops in header files
- __phys_addr on x86_32 became a function in ioremap.c since
  PAGE_OFFSET, is_vmalloc_addr and VMALLOC_* non-constasts are undefined
  if declared in page_32.h
- add __phys_addr_const for initializing doublefault_tss.__cr3

Tested on 386, 386pae, x86_64 and x86_64 numa=fake=2.

Contains Andi's enable numa virtual address debug patch.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 0 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 6e45b0f3d125..dc41e9c8ca6f 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -180,6 +180,11 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
         pmd_t *pmd;
         pte_t *ptep, pte;
 
+        /* XXX we might need to change this if we add VIRTUAL_BUG_ON for
+         * architectures that do not vmalloc module space */
+        VIRTUAL_BUG_ON(!is_vmalloc_addr(vmalloc_addr) &&
+                        !is_module_address(addr));
+
         if (!pgd_none(*pgd)) {
                 pud = pud_offset(pgd, addr);
                 if (!pud_none(*pud)) {