lkml.org 
[lkml]   [2010]   [Feb]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[60/93] devmem: fix kmem write bug on memory holes
2.6.32-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Wu Fengguang <fengguang.wu@intel.com>


commit c85e9a97c4102ce2e83112da850d838cfab5ab13 upstream

devmem: fix kmem write bug on memory holes

[ cebbert@redhat.com : backport to 2.6.32 ]

write_kmem() used to assume vwrite() always return the full buffer length.
However now vwrite() could return 0 to indicate memory hole. This
creates a bug that "buf" is not advanced accordingly.

Fix it to simply ignore the return value, hence the memory hole.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/char/mem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -593,7 +593,7 @@ static ssize_t write_kmem(struct file *
break;
}
}
- len = vwrite(kbuf, (char *)p, len);
+ vwrite(kbuf, (char *)p, len);
count -= len;
buf += len;
virtr += len;



\
 
 \ /
  Last update: 2010-02-19 18:03    [from the cache]
©2003-2011 Jasper Spaans