All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Jianpeng Ma" <majianpeng@gmail.com>
To: linux-kernel <linux-kernel@vger.kernel.org>
Subject: About reuse address space when __init func removed
Date: Mon, 15 Oct 2012 16:52:51 +0800	[thread overview]
Message-ID: <201210151652486099657@gmail.com> (raw)

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset="gb2312", Size: 2241 bytes --]

Hi all,
	Today, I found some kernel message about memeleaking.As follows:
unreferenced object 0xffff8800b6e6b980 (size 64):
  comm "modprobe", pid 1137, jiffies 4294676166 (age 7326.499s)
  hex dump (first 32 bytes):
    01 04 01 00 00 00 00 00 00 00 98 b5 00 88 ff ff  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff816a3f16>] kmemleak_alloc+0x56/0xc0
    [<ffffffff8113bd43>] __kmalloc+0x173/0x310
    [<ffffffffa009a78a>] 0xffffffffa009a78a
    [<ffffffffa009ad95>] 0xffffffffa009ad95
    [<ffffffff81300985>] pci_device_probe+0x75/0xa0
    [<ffffffff814078c4>] driver_probe_device+0x84/0x380
    [<ffffffff81407c63>] __driver_attach+0xa3/0xb0
    [<ffffffff81405a96>] bus_for_each_dev+0x56/0x90
    [<ffffffff81407359>] driver_attach+0x19/0x20
    [<ffffffff81406e80>] bus_add_driver+0x1a0/0x2c0
    [<ffffffff81408195>] driver_register+0x75/0x150
    [<ffffffff812ffa1c>] __pci_register_driver+0x5c/0x70
    [<ffffffffa00a20a7>] nfsd_last_thread+0x47/0x70 [nfsd]
    [<ffffffff810001fa>] do_one_initcall+0x3a/0x170
    [<ffffffff810a7d1c>] sys_init_module+0x8c/0x200
    [<ffffffff816cc352>] system_call_fastpath+0x16/0x1b

But the problem is not memleak, but the stack.
I noticed "[<ffffffffa00a20a7>] nfsd_last_thread+0x47/0x70 [nfsd]".But the real module is mvsas.
Why the kernel print nfsd?

I added some debuginfo in func mvs_init.
diff --git a/drivers/scsi/mvsas/mv_init.c b/drivers/scsi/mvsas/mv_init.c
index cc59dff..d34ce01 100644
--- a/drivers/scsi/mvsas/mv_init.c
+++ b/drivers/scsi/mvsas/mv_init.c
@@ -821,6 +821,7 @@ static int __init mvs_init(void)
 {
        int rc;
        mvs_stt = sas_domain_attach_transport(&mvs_transport_ops);
+       printk(KERN_ERR"%s:0x%lx\n", __func__, _THIS_IP_);
        if (!mvs_stt)
                return -ENOMEM;

The result is "[    3.781487] mvs_init:0xffffffffa00a2000"

I think because the __init attribute.When mvs_init execd,those memeory removed and the address space alse removed.So after func nfsd_last_thread used those address.
Is it a bug?

Thanks!ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

                 reply	other threads:[~2012-10-15  8:52 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=201210151652486099657@gmail.com \
    --to=majianpeng@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.