lkml.org 
[lkml]   [2013]   [Jun]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] x86, range: make add_range use blank slot
Date
Now add_range_with_merge will generate blank slot as subtract_range.
we could reach the array limit because of blank slots.

We can let add_range to have second try to use blank slot.

Also use WARN_ONCE to print trace.

Reported-by: Joshua Covington <joshuacov@googlemail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@vger.kernel.org> v3.9
---
kernel/range.c | 34 ++++++++++++++++++++++------------
1 file changed, 22 insertions(+), 12 deletions(-)

Index: linux-2.6/kernel/range.c
===================================================================
--- linux-2.6.orig/kernel/range.c
+++ linux-2.6/kernel/range.c
@@ -3,23 +3,34 @@
*/
#include <linux/kernel.h>
#include <linux/init.h>
+#include <linux/bug.h>
#include <linux/sort.h>
-
#include <linux/range.h>

int add_range(struct range *range, int az, int nr_range, u64 start, u64 end)
{
- if (start >= end)
- return nr_range;
+ int i;

- /* Out of slots: */
- if (nr_range >= az)
+ if (start >= end)
return nr_range;

- range[nr_range].start = start;
- range[nr_range].end = end;
+ /* Out of slots ? */
+ if (nr_range < az) {
+ i = nr_range;
+ nr_range++;
+ } else {
+ /* find blank slot */
+ for (i = 0; i < az; i++)
+ if (!range[i].end)
+ break;
+ if (i == az) {
+ WARN_ONCE(1, "run out of slot in ranges\n");
+ return az;
+ }
+ }

- nr_range++;
+ range[i].start = start;
+ range[i].end = end;

return nr_range;
}
@@ -98,10 +109,9 @@ void subtract_range(struct range *range,
if (i < az) {
range[i].end = range[j].end;
range[i].start = end;
- } else {
- pr_err("%s: run out of slot in ranges\n",
- __func__);
- }
+ } else
+ WARN_ONCE(1, "run out of slot in ranges\n");
+
range[j].end = start;
continue;
}

\
 
 \ /
  Last update: 2013-06-09 22:21    [W:0.027 / U:2.468 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site