parisc: Fix map_pages() to not overwrite existing pte entries

commit 3c229b3f2dd8133f61bb81d3cb018be92f4bba39 upstream.

Fix a long-existing small nasty bug in the map_pages() implementation which
leads to overwriting already written pte entries with zero, *if* map_pages() is
called a second time with an end address which isn't aligned on a pmd boundry.
This happens for example if we want to remap only the text segment read/write
in order to run alternative patching on the code. Exiting the loop when we
reach the end address fixes this.

Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 13f7854..cc700f7 100644 (file)
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -495,12 +495,8 @@ static void __init map_pages(unsigned long start_vaddr,
                                                pte = pte_mkhuge(pte);
                                }
 
-                               if (address >= end_paddr) {
-                                       if (force)
-                                               break;
-                                       else
-                                               pte_val(pte) = 0;
-                               }
+                               if (address >= end_paddr)
+                                       break;
 
                                set_pte(pg_table, pte);