releases/3.6.8/ttm-clear-the-ttm-page-allocated-from-high-memory-zone-correctly.patch

   1 From ac207ed2471150e06af0afc76e4becc701fa2733 Mon Sep 17 00:00:00 2001
   2 From: Zhao Yakui <yakui.zhao@intel.com>
   3 Date: Tue, 13 Nov 2012 18:31:55 +0000
   4 Subject: ttm: Clear the ttm page allocated from high memory zone correctly
   5
   6 From: Zhao Yakui <yakui.zhao@intel.com>
   7
   8 commit ac207ed2471150e06af0afc76e4becc701fa2733 upstream.
   9
  10 The TTM page can be allocated from high memory. In such case it is
  11 wrong to use the page_address(page) as the virtual address for the high memory
  12 page.
  13
  14 bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=50241
  15
  16 Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
  17 Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
  18 Signed-off-by: Dave Airlie <airlied@redhat.com>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20
  21 ---
  22  drivers/gpu/drm/ttm/ttm_page_alloc.c |    5 ++++-
  23  1 file changed, 4 insertions(+), 1 deletion(-)
  24
  25 --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
  26 +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
  27 @@ -749,7 +749,10 @@ static int ttm_get_pages(struct page **p
  28         /* clear the pages coming from the pool if requested */
  29         if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) {
  30                 list_for_each_entry(p, &plist, lru) {
  31 -                       clear_page(page_address(p));
  32 +                       if (PageHighMem(p))
  33 +                               clear_highpage(p);
  34 +                       else
  35 +                               clear_page(page_address(p));
  36                 }
  37         }
  38