# Re: \[PATCH v8 07/11\] proc: flush task dcache entries from all procfs instances

- From: Linus Torvalds \<torvalds@linux-foundation.org\>
- Date: 2020-02-12 20:41:53 
- List: linux-security-module
- Page: https://ratatoskr.run/linux-security-module/2020/02/172670
- Thread: https://ratatoskr.run/linux-api/2020/02/172639/t.md

```text
On Wed, Feb 12, 2020 at 12:03 PM Al Viro [ref] wrote:
>
> What's to prevent racing with fs shutdown while you are doing the second part?

I was thinking that only the proc_flush_task() code would do this.

And that holds a ref to the vfsmount through upid->ns.

So I wasn't suggesting doing this in general - just splitting up the
implementation of d_invalidate() so that proc_flush_task_mnt() could
delay the complex part to after having traversed the RCU-protected
list.

But hey - I missed this part of the problem originally, so maybe I'm
just missing something else this time. Wouldn't be the first time.

               Linus
```