lkml.org 
[lkml]   [2011]   [May]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject答复: problem with kmemleak
Date
Thx, Maxin :)
ok
I did steps below:
1 make oldconfig
2 vim .config
...
CONFIG_DEBUG_FS = y
CONFIG_DEBUG_KMEMLEAK = y
CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE = 1200
...
3 make ; make modules ; and replace the kernel; reboot
4 mount -t debugfs debugfs /sys/kernel/debug
4 I wrote a module like this
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/vmalloc.h>

void myfunc(void)
{
char *ptr;
ptr = vmalloc(512);
ptr = vmalloc(512);
ptr = vmalloc(512);
}

int hello_init(void)
{
printk(KERN_ALERT "Hello World");
myfunc();
return 0;
}

static void hello_exit(void)
{
printk(KERN_ALERT "Goodbye World");
}

module_init(hello_init);
module_exit(hello_exit);

MODULE_LICENSE("GPL v2");

5 clear the kmemleak
Echo clear > /sys/kernel/debug/kmemleak
6 insmod the module
Insmod xxx.ko
7 echo scan > /sys/kenel/debug/kmemleak
8 watch it
Cat / sys/kenel/debug/kmemleak
>> unreferenced object 0xffffc90012d27000 (size 64):
>>
>> comm "insmod", pid 13092, jiffies 4298369684
>>
>> hex dump (first 32 bytes):
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> backtrace:
>>
>> [<ffffffffffffffff>] 0xffffffffffffffff
>>
And I can only get the backtrace [<ffffffffffffffff>]

BTW the kernel's version is 2.6.32.

Thx to Maxin again~~~:)
-----邮件原件-----
发件人: linux-kernel-owner@vger.kernel.org [mailto:linux-kernel-owner@vger.kernel.org] 代表 Maxin B John
发送时间: 2011年5月12日 17:44
收件人: ttlxzz ccc
抄送: linux-kernel@vger.kernel.org
主题: Re: problem with kmemleak

Hi,

Could you please share some more information about your setup ?

Regards,
Maxin

On Thu, May 12, 2011 at 4:13 AM, ttlxzz ccc <boyzccc@gmail.com> wrote:
> help~~~:) please !thx!!
>
> On Thu, May 12, 2011 at 10:06 AM, ttlxzz ccc <boyzccc@gmail.com> wrote:
>> Hi, all:
>>
>>
>>
>> I just want to use kmemleak, so I make the CONFIG_DEBUG_KMEMLEAK and
>> CONFIG_DEBUG_FS on, mount the debugfs.
>>
>> But when I insmod mm/kmemleak-test.ko, echo scan >
>> /sys/kernel/debug/kmemleak and cat /sys/kernel/debug/kmemleak. I just
>> see this:
>>
>> unreferenced object 0xffffc90012d21000 (size 64):
>>
>> comm "insmod", pid 13092, jiffies 4298369684
>>
>> hex dump (first 32 bytes):
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> backtrace:
>>
>> [<ffffffffffffffff>] 0xffffffffffffffff
>>
>> unreferenced object 0xffffc90012d24000 (size 64):
>>
>> comm "insmod", pid 13092, jiffies 4298369684
>>
>> hex dump (first 32 bytes):
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> backtrace:
>>
>> [<ffffffffffffffff>] 0xffffffffffffffff
>>
>> unreferenced object 0xffffc90012d27000 (size 64):
>>
>> comm "insmod", pid 13092, jiffies 4298369684
>>
>> hex dump (first 32 bytes):
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>
>> backtrace:
>>
>> [<ffffffffffffffff>] 0xffffffffffffffff
>>
>> There is no other backtrace except [<ffffffffffffffff>]
>> 0xffffffffffffffff. Then I read the mm/kmemleak.c. In
>> kmemleak_seq_show(), I find that the object->trace_len is 1.
>>
>>
>>
>> How can I get the full backtrace?
>>
> --
> 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/
>
--
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/

--
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: 2011-05-12 12:01    [W:0.116 / U:0.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site