lkml.org 
[lkml]   [2006]   [Nov]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] i386: clear_fixmap() should not use set_pte()
While not strictly required with the current code (as the upper half of
page table entries generated by __set_fixmap() cannot be non-zero due
to the second parameter of this function being 'unsigned long'), the
use of set_pte() in __set_fixmap() in the context of clear_fixmap() is
still improper with CONFIG_X86_PAE (see the respective comment in
include/asm-i386/pgtable-3level.h) and would turn into a bug if that
second parameter ever gets changed to a 64-bit type.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

--- linux-2.6.19-rc5/arch/i386/mm/pgtable.c 2006-11-08 09:21:37.000000000 +0100
+++ 2.6.19-rc5-i386-clear_fixmap/arch/i386/mm/pgtable.c 2006-11-06 12:13:29.000000000 +0100
@@ -95,8 +95,11 @@ static void set_pte_pfn(unsigned long va
return;
}
pte = pte_offset_kernel(pmd, vaddr);
- /* <pfn,flags> stored as-is, to permit clearing entries */
- set_pte(pte, pfn_pte(pfn, flags));
+ if (pgprot_val(flags))
+ /* <pfn,flags> stored as-is, to permit clearing entries */
+ set_pte(pte, pfn_pte(pfn, flags));
+ else
+ pte_clear(&init_mm, vaddr, pte);

/*
* It's enough to flush this one mapping.

-
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: 2006-11-15 15:57    [W:0.022 / U:0.208 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site