Re: NULL pointer dereference in sysfs_hash_and_remove()

[Maneesh Soni <maneesh@in.ibm.com>]

Hi Martin,

Here the dentry corresponding to the attribute subgroup seems to
be a negative dentry. We are ethier reomving the group more
than once or removing a non-existing attribute group. I suspect the
first thing more. Can you rebuild the kernel with DEBUG defined in 
fs/sysfs/dir.c and retest?. And send the dmesg log.

Thanks
Maneesh

On Fri, Oct 03, 2003 at 10:42:39PM +0000, Martin Josefsson wrote:
> Hi
> 
> I compiled 2.6.0-test6 and ran it on a laptop with cardbus.
> I have an Xircom NIC and if I remove it during operation I get the bug
> below.
> 
> I have yenta_socket and xircom_cb loaded as modules.
> 
> 
> Unable to handle kernel NULL pointer dereference at virtual address 00000068
>  printing eip:
> c017cd75
> *pde = 0df96067
> *pte = 00000000
> Oops: 0002 [#1]
> CPU:    0
> EIP:    0060:[<c017cd75>]    Not tainted
> EFLAGS: 00010282
> EIP is at sysfs_hash_and_remove+0x15/0x7d
> eax: 00000000   ebx: c03109e4   ecx: 00000068   edx: ccf13dd0
> esi: ccf13d60   edi: c03106e4   ebp: cea5c454   esp: cd0ede54
> ds: 007b   es: 007b   ss: 0068
> Process pccardd (pid: 528, threadinfo=cd0ec000 task=ce1c8740)
> Stack: c017cd55 cd0ede60 c03109e4 ccf13d60 c017e231 ccf13d60 c02c390f ccf13d60 
>        c0310a40 c017e368 ccf13d60 c0310a40 cfc2dc00 cfc2dd90 c023e937 cfc2dd98 
>        c0310a40 cfc2dc00 cd0edeb4 c023b99a cfc2dc00 00000006 cfc2dc00 00000282 
> Call Trace:
>  [<c017cd55>] sysfs_get_dentry+0x65/0x70
>  [<c017e231>] remove_files+0x31/0x40
>  [<c017e368>] sysfs_remove_group+0x28/0x70
>  [<c023e937>] netdev_unregister_sysfs+0x67/0x70
>  [<c023b99a>] netdev_run_todo+0xea/0x1f0
>  [<d086738c>] xircom_remove+0xac/0xd0 [xircom_cb]
>  [<c01a9deb>] pci_device_remove+0x3b/0x40
>  [<c01e9316>] device_release_driver+0x66/0x70
>  [<c01e9455>] bus_remove_device+0x55/0xa0
>  [<c01e81bd>] device_del+0x5d/0xa0
>  [<c01e8213>] device_unregister+0x13/0x30
>  [<c01a740e>] pci_destroy_dev+0x1e/0x70
>  [<c01a752b>] pci_remove_behind_bridge+0x2b/0x40
>  [<c0221b48>] shutdown_socket+0x88/0x120
>  [<c0222263>] socket_remove+0x13/0x50
>  [<c022230a>] socket_detect_change+0x6a/0x90
>  [<c02224c8>] pccardd+0x198/0x220
>  [<c011a980>] default_wake_function+0x0/0x30
>  [<c011a980>] default_wake_function+0x0/0x30
>  [<c0222330>] pccardd+0x0/0x220
>  [<c01092a5>] kernel_thread_helper+0x5/0x10
> 
> Code: ff 48 68 78 63 89 34 24 8b 44 24 18 89 44 24 04 e8 66 ff ff 
>  
> -- 
> /Martin
> -
> 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/
> 

-- 
Maneesh Soni
Linux Technology Center, 
IBM Software Lab, Bangalore, India
email: maneesh@in.ibm.com
Phone: 91-80-5044999 Fax: 91-80-5268553
T/L : 9243696