[PATCH] netfs: Delete subtree of 'fs/netfs' when netfs module exits

[Baokun Li]

On 2024/8/28 19:22, Christian Brauner wrote:
> On Mon, 26 Aug 2024 19:34:04 +0800, libaokun at huaweicloud.com wrote:
>> In netfs_init() or fscache_proc_init(), we create dentry under 'fs/netfs',
>> but in netfs_exit(), we only delete the proc entry of 'fs/netfs' without
>> deleting its subtree. This triggers the following WARNING:
>>
>> ==================================================================
>> remove_proc_entry: removing non-empty directory 'fs/netfs', leaking at least 'requests'
>> WARNING: CPU: 4 PID: 566 at fs/proc/generic.c:717 remove_proc_entry+0x160/0x1c0
>> Modules linked in: netfs(-)
>> CPU: 4 UID: 0 PID: 566 Comm: rmmod Not tainted 6.11.0-rc3 #860
>> RIP: 0010:remove_proc_entry+0x160/0x1c0
>> Call Trace:
>>   <TASK>
>>   netfs_exit+0x12/0x620 [netfs]
>>   __do_sys_delete_module.isra.0+0x14c/0x2e0
>>   do_syscall_64+0x4b/0x110
>>   entry_SYSCALL_64_after_hwframe+0x76/0x7e
>> ==================================================================

Hi Christian,


Thank you for applying this patch!

I just realized that the parentheses are in the wrong place here,
could you please help me correct them?
>> Therefore use remove_proc_subtree instead() of remove_proc_entry() to
^^ remove_proc_subtree() instead

Regards, Baokun

> Applied to the vfs.misc branch of the vfs/vfs.git tree.
> Patches in the vfs.misc branch should appear in linux-next soon.
>
> Please report any outstanding bugs that were missed during review in a
> new review to the original patch series allowing us to drop it.
>
> It's encouraged to provide Acked-bys and Reviewed-bys even though the
> patch has now been applied. If possible patch trailers will be updated.
>
> Note that commit hashes shown below are subject to change due to rebase,
> trailer updates or similar. If in doubt, please check the listed branch.
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
> branch: vfs.misc
>
> [1/1] netfs: Delete subtree of 'fs/netfs' when netfs module exits
>        https://git.kernel.org/vfs/vfs/c/0aef59b3eabb