Re: 38-rc1: umount+rmmod cause ext4 error.

[Maciej Rutecki]

I created a Bugzilla entry at 
https://bugzilla.kernel.org/show_bug.cgi?id=27652
for your bug report, please add your address to the CC list in there, thanks!

On Åroda, 19 stycznia 2011 o 07:53:36 Tao Ma wrote:
> Hi Nick and Ted,
> 	I ran some very basic test with 38-rc1 and my box run into error with
> the message like:
> 
> slab error in kmem_cache_destroy(): cache `ext4_inode_cache': Can't free
> all objects
> Pid: 4395, comm: rmmod Not tainted 2.6.38-rc1 #1
> Call Trace:
>   [<ffffffff820d61dc>] ? kmem_cache_destroy+0x83/0xc7
>   [<ffffffffa0574025>] ? destroy_inodecache+0x15/0x17 [ext4]
>   [<ffffffffa05923d1>] ? ext4_exit_fs+0x109/0x143 [ext4]
>   [<ffffffff8203d194>] ? put_online_cpus+0x56/0x58
>   [<ffffffff8206735a>] ? module_refcount+0x85/0x9d
>   [<ffffffff82067b22>] ? sys_delete_module+0x1b5/0x218
>   [<ffffffff82074fc3>] ? audit_syscall_entry+0x187/0x1ba
>   [<ffffffff82002a6b>] ? system_call_fastpath+0x16/0x1b
> SLAB: cache with size 888 has lost its name
> SLAB: cache with size 888 has lost its name
> SLAB: cache with size 888 has lost its name
> SLAB: cache with size 888 has lost its name
> 
> The reproduce process is simple:just rmmod ext4 immediately after umount
> an ext4 volume.
> 
> I have done some very simple investigation and it seems that with Nick's
> new ext4_i_callback, even after we do ext4_destroy_inode, it isn't
> freed. So after we destroy the ext_inode_cache, and when freeing the
> inode, it errors. Hope it helps. If you have any fixes, I can test it.
> 
> Regards,
> Tao
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

-- 
Maciej Rutecki
http://www.maciek.unixy.pl
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/