lkml.org 
[lkml]   [2003]   [Jan]   [17]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
DateThu, 16 Jan 2003 21:51:28 -0800
FromWilliam Lee Irwin III <>
Subjecti386 pgd_index() doesn't parenthesize its arg
pgd_index() doesn't parenthesize its argument. This is a bad idea for
macros, since it's legitimate to pass expressions to them that will
get misinterpreted given operator precedence and the shift.

vs. 2.5.59


-- wli


===== include/asm-i386/pgtable.h 1.22 vs edited =====
--- 1.22/include/asm-i386/pgtable.h	Mon Nov 25 14:41:15 2002
+++ edited/include/asm-i386/pgtable.h	Thu Jan 16 21:08:06 2003
@@ -242,7 +242,7 @@
 	((pmd_val(pmd) & (_PAGE_PSE|_PAGE_PRESENT)) == (_PAGE_PSE|_PAGE_PRESENT))
 
 /* to find an entry in a page-table-directory. */
-#define pgd_index(address) ((address >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
+#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
 
 #define __pgd_offset(address) pgd_index(address)
 
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2005-03-22 12:32    [from the cache]
©2003-2008