Re: [3.1-rc6] kmalloc(64) leak from IDE

From: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
To: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org
Subject: Re: [3.1-rc6] kmalloc(64) leak from IDE
Date: Fri, 23 Sep 2011 18:34:42 +0200	[thread overview]
Message-ID: <4E7CB522.6080208@itwm.fraunhofer.de> (raw)
In-Reply-To: <CAErSpo4H9_Fwyic9crHTGwWaDk5bevK7r6pTb+tpMFxHZ2MajQ@mail.gmail.com>

On 09/23/2011 06:08 PM, Bjorn Helgaas wrote:
> On Fri, Sep 23, 2011 at 9:58 AM, Bernd Schubert
> <bernd.schubert@itwm.fraunhofer.de>  wrote:
>> On 09/23/2011 09:21 AM, Borislav Petkov wrote:
>>>
>>> On Thu, Sep 22, 2011 at 01:23:37PM -0700, Simon Kirby wrote:
>>>>
>>>> Yes, that seems to have made it stop complaining about the IDE path.
>>>
>>> Good, thanks for testing. It would be great if you left it running for
>>> a couple of days like this to see whether there aren't any other issues
>>> with the patch. I'll send it with a proper description to Dave soonish
>>> since this is a real bug.
>>>
>>>> All I see from kmemleak now is:
>>>
>>> Yep, not IDE-related. Adding linux-acpi.
>>
>>
>>>
>>>> unreferenced object 0xe7481a00 (size 256):
>>>>    comm "swapper", pid 1, jiffies 4294892509 (age 515.560s)
>>>>    hex dump (first 32 bytes):
>>>>      00 00 00 28 ff ff ef ff 60 78 4e e7 00 02 00 00  ...(....`xN.....
>>>>      47 01 f8 0c f8 0c 01 08 00 00 00 00 0c 03 00 00  G...............
>>>>    backtrace:
>>>>      [<c1495c47>] kmemleak_alloc+0x27/0x50
>>>>      [<c10b3563>] __kmalloc+0xf3/0x1c0
>>>>      [<c149e0b0>] pci_acpi_scan_root+0x11e/0x272
>>>>      [<c149916b>] acpi_pci_root_add+0x163/0x256
>>>>      [<c12adddc>] acpi_device_probe+0x3a/0xf4
>>>>      [<c1302e38>] driver_probe_device+0x68/0x160
>>>>      [<c1302fb9>] __driver_attach+0x89/0x90
>>>>      [<c1302718>] bus_for_each_dev+0x48/0x70
>>>>      [<c1302cc9>] driver_attach+0x19/0x20
>>>>      [<c130213f>] bus_add_driver+0x17f/0x240
>>>>      [<c1303345>] driver_register+0x65/0x120
>>>>      [<c12af273>] acpi_bus_register_driver+0x3a/0x3f
>>>>      [<c16d421f>] acpi_pci_root_init+0x1b/0x2a
>>>>      [<c1001030>] do_one_initcall+0x30/0x160
>>>>      [<c16b920b>] kernel_init+0x78/0x10c
>>>>      [<c14a1b76>] kernel_thread_helper+0x6/0xd
>>>> unreferenced object 0xe74e7860 (size 16):
>>>>    comm "swapper", pid 1, jiffies 4294892509 (age 515.560s)
>>>>    hex dump (first 16 bytes):
>>>>      50 43 49 20 42 75 73 20 30 30 30 30 3a 30 30 00  PCI Bus 0000:00.
>>>>    backtrace:
>>>>      [<c1495c47>] kmemleak_alloc+0x27/0x50
>>>>      [<c10b3563>] __kmalloc+0xf3/0x1c0
>>>>      [<c1290cce>] kvasprintf+0x2e/0x50
>>>>      [<c1290d01>] kasprintf+0x11/0x20
>>>>      [<c149e0da>] pci_acpi_scan_root+0x148/0x272
>>>>      [<c149916b>] acpi_pci_root_add+0x163/0x256
>>>>      [<c12adddc>] acpi_device_probe+0x3a/0xf4
>>>>      [<c1302e38>] driver_probe_device+0x68/0x160
>>>>      [<c1302fb9>] __driver_attach+0x89/0x90
>>>>      [<c1302718>] bus_for_each_dev+0x48/0x70
>>>>      [<c1302cc9>] driver_attach+0x19/0x20
>>>>      [<c130213f>] bus_add_driver+0x17f/0x240
>>>>      [<c1303345>] driver_register+0x65/0x120
>>>>      [<c12af273>] acpi_bus_register_driver+0x3a/0x3f
>>>>      [<c16d421f>] acpi_pci_root_init+0x1b/0x2a
>>>>      [<c1001030>] do_one_initcall+0x30/0x160
>>>>
>>>> ...which is probably a separate, non-recurring leak.
>>>>
>>>>> Also, I'm sure you know IDE is deprecated, so what are the chances of
>>>>> moving this box to libata? Also, can you send me your .config pls?
>>>>
>>>> Yeah, I was going to get around to that eventually. :) Config (and
>>>> earlier kmemleak output) here: http://0x.ca/sim/ref/3.1-rc6-blue/
>>>
>>> Ok, thanks.
>>>
>>
>> I think I reported those already some time ago:
>>
>> https://lkml.org/lkml/2011/6/21/95
>
> Rats.  And you even posted a patch
> (https://lkml.org/lkml/2011/6/21/132).  I was cc'd, but unfortunately
> to an old email address that no longer works.  I'll follow up on it
> and make sure it's fixed (probably in 3.2 since it's minor and we're
> so late in 3.1).

Ah great, I thought you are simply too busy to look into it. We are all 
just changing our mail addresses too often :)

Do you mind if I ping you directly once kernel.org is up again? We have 
a few test systems here, that fail to boot with recent kernels (just a 
system hard reset). The issue was introduced in between 2.6.27 and 
2.6.32 and it is pci mmconfig related, probably due to a troublesome 
acpi bios. I filled a bugzilla some time ago and never got a responds on 
it. But I also need to update it with my latest finding...

Thanks,
Bernd